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Johannes Weiner [Sun, 1 Dec 2019 01:56:02 +0000 (17:56 -0800)]
mm: vmscan: enforce inactive:active ratio at the reclaim root
We split the LRU lists into inactive and an active parts to maximize
workingset protection while allowing just enough inactive cache space to
faciltate readahead and writeback for one-off file accesses (e.g. a
linear scan through a file, or logging); or just enough inactive anon to
maintain recent reference information when reclaim needs to swap.
With cgroups and their nested LRU lists, we currently don't do this
correctly. While recursive cgroup reclaim establishes a relative LRU
order among the pages of all involved cgroups, inactive:active size
decisions are done on a per-cgroup level. As a result, we'll reclaim a
cgroup's workingset when it doesn't have cold pages, even when one of its
siblings has plenty of it that should be reclaimed first.
For example: workload A has 50M worth of hot cache but doesn't do any
one-off file accesses; meanwhile, parallel workload B scans files and
rarely accesses the same page twice.
If these workloads were to run in an uncgrouped system, A would be
protected from the high rate of cache faults from B. But if they were put
in parallel cgroups for memory accounting purposes, B's fast cache fault
rate would push out the hot cache pages of A. This is unexpected and
undesirable - the "scan resistance" of the page cache is broken.
This patch moves inactive:active size balancing decisions to the root of
reclaim - the same level where the LRU order is established.
It does this by looking at the recursive size of the inactive and the
active file sets of the cgroup subtree at the beginning of the reclaim
cycle, and then making a decision - scan or skip active pages - that
applies throughout the entire run and to every cgroup involved.
With that in place, in the test above, the VM will recognize that there
are plenty of inactive pages in the combined cache set of workloads A and
B and prefer the one-off cache in B over the hot pages in A. The scan
resistance of the cache is restored.
[cai@lca.pw: fix some -Wenum-conversion warnings]
Link: http://lkml.kernel.org/r/1573848697-29262-1-git-send-email-cai@lca.pw
Link: http://lkml.kernel.org/r/20191107205334.158354-4-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:59 +0000 (17:55 -0800)]
mm: vmscan: detect file thrashing at the reclaim root
We use refault information to determine whether the cache workingset is
stable or transitioning, and dynamically adjust the inactive:active file
LRU ratio so as to maximize protection from one-off cache during stable
periods, and minimize IO during transitions.
With cgroups and their nested LRU lists, we currently don't do this
correctly. While recursive cgroup reclaim establishes a relative LRU
order among the pages of all involved cgroups, refaults only affect the
local LRU order in the cgroup in which they are occuring. As a result,
cache transitions can take longer in a cgrouped system as the active pages
of sibling cgroups aren't challenged when they should be.
[ Right now, this is somewhat theoretical, because the siblings, under
continued regular reclaim pressure, should eventually run out of
inactive pages - and since inactive:active *size* balancing is also
done on a cgroup-local level, we will challenge the active pages
eventually in most cases. But the next patch will move that relative
size enforcement to the reclaim root as well, and then this patch
here will be necessary to propagate refault pressure to siblings. ]
This patch moves refault detection to the root of reclaim. Instead of
remembering the cgroup owner of an evicted page, remember the cgroup that
caused the reclaim to happen. When refaults later occur, they'll
correctly influence the cross-cgroup LRU order that reclaim follows.
I.e. if global reclaim kicked out pages in some subgroup A/B/C, the
refault of those pages will challenge the global LRU order, and not just
the local order down inside C.
[hannes@cmpxchg.org: use page_memcg() instead of another lookup]
Link: http://lkml.kernel.org/r/20191115160722.GA309754@cmpxchg.org
Link: http://lkml.kernel.org/r/20191107205334.158354-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:56 +0000 (17:55 -0800)]
mm: vmscan: move file exhaustion detection to the node level
Patch series "mm: fix page aging across multiple cgroups".
When applications are put into unconfigured cgroups for memory accounting
purposes, the cgrouping itself should not change the behavior of the page
reclaim code. We expect the VM to reclaim the coldest pages in the
system. But right now the VM can reclaim hot pages in one cgroup while
there is eligible cold cache in others.
This is because one part of the reclaim algorithm isn't truly cgroup
hierarchy aware: the inactive/active list balancing. That is the part
that is supposed to protect hot cache data from one-off streaming IO.
The recursive cgroup reclaim scheme will scan and rotate the physical LRU
lists of each eligible cgroup at the same rate in a round-robin fashion,
thereby establishing a relative order among the pages of all those
cgroups. However, the inactive/active balancing decisions are made
locally within each cgroup, so when a cgroup is running low on cold pages,
its hot pages will get reclaimed - even when sibling cgroups have plenty
of cold cache eligible in the same reclaim run.
For example:
[root@ham ~]# head -n1 /proc/meminfo
MemTotal:
1016336 kB
[root@ham ~]# ./reclaimtest2.sh
Establishing 50M active files in cgroup A...
Hot pages cached: 12800/12800 workingset-a
Linearly scanning through 18G of file data in cgroup B:
real 0m4.269s
user 0m0.051s
sys 0m4.182s
Hot pages cached: 134/12800 workingset-a
The streaming IO in B, which doesn't benefit from caching at all, pushes
out most of the workingset in A.
Solution
This series fixes the problem by elevating inactive/active balancing
decisions to the toplevel of the reclaim run. This is either a cgroup
that hit its limit, or straight-up global reclaim if there is physical
memory pressure. From there, it takes a recursive view of the cgroup
subtree to decide whether page deactivation is necessary.
In the test above, the VM will then recognize that cgroup B has plenty of
eligible cold cache, and that the hot pages in A can be spared:
[root@ham ~]# ./reclaimtest2.sh
Establishing 50M active files in cgroup A...
Hot pages cached: 12800/12800 workingset-a
Linearly scanning through 18G of file data in cgroup B:
real 0m4.244s
user 0m0.064s
sys 0m4.177s
Hot pages cached: 12800/12800 workingset-a
Implementation
Whether active pages can be deactivated or not is influenced by two
factors: the inactive list dropping below a minimum size relative to the
active list, and the occurence of refaults.
This patch series first moves refault detection to the reclaim root, then
enforces the minimum inactive size based on a recursive view of the cgroup
tree's LRUs.
History
Note that this actually never worked correctly in Linux cgroups. In the
past it worked for global reclaim and leaf limit reclaim only (we used to
have two physical LRU linkages per page), but it never worked for
intermediate limit reclaim over multiple leaf cgroups.
We're noticing this now because 1) we're putting everything into cgroups
for accounting, not just the things we want to control and 2) we're moving
away from leaf limits that invoke reclaim on individual cgroups, toward
large tree reclaim, triggered by high-level limits, or physical memory
pressure that is influenced by local protections such as memory.low and
memory.min instead.
This patch (of 3):
When file pages are lower than the watermark on a node, we try to force
scan anonymous pages to counter-act the balancing algorithms preference
for new file pages when they are likely thrashing. This is a node-level
decision, but it's currently made each time we look at an lruvec. This is
unnecessarily expensive and also a layering violation that makes the code
harder to understand.
Clean this up by making the check once per node and setting a flag in the
scan_control.
Link: http://lkml.kernel.org/r/20191107205334.158354-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:52 +0000 (17:55 -0800)]
mm: vmscan: harmonize writeback congestion tracking for nodes & memcgs
The current writeback congestion tracking has separate flags for kswapd
reclaim (node level) and cgroup limit reclaim (memcg-node level). This is
unnecessarily complicated: the lruvec is an existing abstraction layer for
that node-memcg intersection.
Introduce lruvec->flags and LRUVEC_CONGESTED. Then track that at the
reclaim root level, which is either the NUMA node for global reclaim, or
the cgroup-node intersection for cgroup reclaim.
Link: http://lkml.kernel.org/r/20191022144803.302233-9-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:49 +0000 (17:55 -0800)]
mm: vmscan: split shrink_node() into node part and memcgs part
This function is getting long and unwieldy, split out the memcg bits.
The updated shrink_node() handles the generic (node) reclaim aspects:
- global vmpressure notifications
- writeback and congestion throttling
- reclaim/compaction management
- kswapd giving up on unreclaimable nodes
It then calls a new shrink_node_memcgs() which handles cgroup specifics:
- the cgroup tree traversal
- memory.low considerations
- per-cgroup slab shrinking callbacks
- per-cgroup vmpressure notifications
[hannes@cmpxchg.org: rename "root" to "target_memcg", per Roman]
Link: http://lkml.kernel.org/r/20191025143640.GA386981@cmpxchg.org
Link: http://lkml.kernel.org/r/20191022144803.302233-8-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:46 +0000 (17:55 -0800)]
mm: vmscan: turn shrink_node_memcg() into shrink_lruvec()
An lruvec holds LRU pages owned by a certain NUMA node and cgroup.
Instead of awkwardly passing around a combination of a pgdat and a memcg
pointer, pass down the lruvec as soon as we can look it up.
Nested callers that need to access node or cgroup properties can look them
them up if necessary, but there are only a few cases.
Link: http://lkml.kernel.org/r/20191022144803.302233-7-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:43 +0000 (17:55 -0800)]
mm: vmscan: replace shrink_node() loop with a retry jump
Most of the function body is inside a loop, which imposes an additional
indentation and scoping level that makes the code a bit hard to follow and
modify.
The looping only happens in case of reclaim-compaction, which isn't the
common case. So rather than adding yet another function level to the
reclaim path and have every reclaim invocation go through a level that
only exists for one specific cornercase, use a retry goto.
Link: http://lkml.kernel.org/r/20191022144803.302233-6-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:40 +0000 (17:55 -0800)]
mm: vmscan: naming fixes: global_reclaim() and sane_reclaim()
Seven years after introducing the global_reclaim() function, I still have
to double take when reading a callsite. I don't know how others do it,
this is a terrible name.
Invert the meaning and rename it to cgroup_reclaim().
[ After all, "global reclaim" is just regular reclaim invoked from the
page allocator. It's reclaim on behalf of a cgroup limit that is a
special case of reclaim, and should be explicit - not the reverse. ]
sane_reclaim() isn't very descriptive either: it tests whether we can use
the regular writeback throttling - available during regular page reclaim
or cgroup2 limit reclaim - or need to use the broken
wait_on_page_writeback() method. Use "writeback_throttling_sane()".
Link: http://lkml.kernel.org/r/20191022144803.302233-5-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:37 +0000 (17:55 -0800)]
mm: vmscan: move inactive_list_is_low() swap check to the caller
inactive_list_is_low() should be about one thing: checking the ratio
between inactive and active list. Kitchensink checks like the one for
swap space makes the function hard to use and modify its callsites.
Luckly, most callers already have an understanding of the swap situation,
so it's easy to clean up.
get_scan_count() has its own, memcg-aware swap check, and doesn't even get
to the inactive_list_is_low() check on the anon list when there is no swap
space available.
shrink_list() is called on the results of get_scan_count(), so that check
is redundant too.
age_active_anon() has its own totalswap_pages check right before it checks
the list proportions.
The shrink_node_memcg() site is the only one that doesn't do its own swap
check. Add it there.
Then delete the swap check from inactive_list_is_low().
Link: http://lkml.kernel.org/r/20191022144803.302233-4-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:34 +0000 (17:55 -0800)]
mm: clean up and clarify lruvec lookup procedure
There is a per-memcg lruvec and a NUMA node lruvec. Which one is being
used is somewhat confusing right now, and it's easy to make mistakes -
especially when it comes to global reclaim.
How it works: when memory cgroups are enabled, we always use the
root_mem_cgroup's per-node lruvecs. When memory cgroups are not compiled
in or disabled at runtime, we use pgdat->lruvec.
Document that in a comment.
Due to the way the reclaim code is generalized, all lookups use the
mem_cgroup_lruvec() helper function, and nobody should have to find the
right lruvec manually right now. But to avoid future mistakes, rename the
pgdat->lruvec member to pgdat->__lruvec and delete the convenience wrapper
that suggests it's a commonly accessed member.
While in this area, swap the mem_cgroup_lruvec() argument order. The name
suggests a memcg operation, yet it takes a pgdat first and a memcg second.
I have to double take every time I call this. Fix that.
Link: http://lkml.kernel.org/r/20191022144803.302233-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:55:31 +0000 (17:55 -0800)]
mm: vmscan: simplify lruvec_lru_size()
Patch series "mm: vmscan: cgroup-related cleanups".
Here are 8 patches that clean up the reclaim code's interaction with
cgroups a bit. They're not supposed to change any behavior, just make
the implementation easier to understand and work with.
This patch (of 8):
This function currently takes the node or lruvec size and subtracts the
zones that are excluded by the classzone index of the allocation. It uses
four different types of counters to do this.
Just add up the eligible zones.
[cai@lca.pw: fix an undefined behavior for zone id]
Link: http://lkml.kernel.org/r/20191108204407.1435-1-cai@lca.pw
[akpm@linux-foundation.org: deal with the MAX_NR_ZONES special case. per Qian Cai]
Link: http://lkml.kernel.org/r/64E60F6F-7582-427B-8DD5-EF97B1656F5A@lca.pw
Link: http://lkml.kernel.org/r/20191022144803.302233-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yang Shi [Sun, 1 Dec 2019 01:55:28 +0000 (17:55 -0800)]
mm/vmscan.c: remove unused scan_control parameter from pageout()
Since lumpy reclaim was removed in v3.5 scan_control is not used by
may_write_to_{queue|inode} and pageout() anymore, remove the unused
parameter.
Link: http://lkml.kernel.org/r/1570124498-19300-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Ryabinin [Sun, 1 Dec 2019 01:55:24 +0000 (17:55 -0800)]
mm/vmscan: remove unused lru_pages argument
Since
9092c71bb724 ("mm: use sc->priority for slab shrink targets") the
argument 'unsigned long *lru_pages' passed around with no purpose. Remove
it.
Link: http://lkml.kernel.org/r/20190228083329.31892-4-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
lijiazi [Sun, 1 Dec 2019 01:55:21 +0000 (17:55 -0800)]
mm/page_alloc.c: print reserved_highatomic info
Print nr_reserved_highatomic in show_free_areas, because when alloc_harder
is false, this value will be subtracted from the free_pages in
__zone_watermark_ok. Printing this value can help analyze memory
allocaction failure issues.
Link: http://lkml.kernel.org/r/19515f3de2fb6abe66b52e03e4b676a21e82beda.1573634806.git.lijiazi@xiaomi.com
Signed-off-by: lijiazi <lijiazi@xiaomi.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hao Lee [Sun, 1 Dec 2019 01:55:18 +0000 (17:55 -0800)]
include/linux/mmzone.h: fix comment for ISOLATE_UNMAPPED macro
Both file-backed pages and anonymous pages can be unmapped.
ISOLATE_UNMAPPED is not just for file-backed pages.
Link: http://lkml.kernel.org/r/20191024151621.GA20400@haolee.github.io
Signed-off-by: Hao Lee <haolee.swjtu@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Sun, 1 Dec 2019 01:55:15 +0000 (17:55 -0800)]
mm, pcpu: make zone pcp updates and reset internal to the mm
Memory hotplug needs to be able to reset and reinit the pcpu allocator
batch and high limits but this action is internal to the VM. Move the
declaration to internal.h
Link: http://lkml.kernel.org/r/20191021094808.28824-4-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Qian Cai <cai@lca.pw>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Sun, 1 Dec 2019 01:55:11 +0000 (17:55 -0800)]
mm, pcp: share common code between memory hotplug and percpu sysctl handler
Both the percpu_pagelist_fraction sysctl handler and memory hotplug have
a common requirement of updating the pcpu page allocation batch and high
values. Split the relevant helper to share common code.
No functional change.
Link: http://lkml.kernel.org/r/20191021094808.28824-3-mgorman@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Qian Cai <cai@lca.pw>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Anshuman Khandual [Sun, 1 Dec 2019 01:55:06 +0000 (17:55 -0800)]
mm/page_alloc: add alloc_contig_pages()
HugeTLB helper alloc_gigantic_page() implements fairly generic
allocation method where it scans over various zones looking for a large
contiguous pfn range before trying to allocate it with
alloc_contig_range().
Other than deriving the requested order from 'struct hstate', there is
nothing HugeTLB specific in there. This can be made available for
general use to allocate contiguous memory which could not have been
allocated through the buddy allocator.
alloc_gigantic_page() has been split carving out actual allocation
method which is then made available via new alloc_contig_pages() helper
wrapped under CONFIG_CONTIG_ALLOC. All references to 'gigantic' have
been replaced with more generic term 'contig'. Allocated pages here
should be freed with free_contig_range() or by calling __free_page() on
each allocated page.
Link: http://lkml.kernel.org/r/1571300646-32240-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Axtens [Sun, 1 Dec 2019 01:55:00 +0000 (17:55 -0800)]
x86/kasan: support KASAN_VMALLOC
In the case where KASAN directly allocates memory to back vmalloc space,
don't map the early shadow page over it.
We prepopulate pgds/p4ds for the range that would otherwise be empty.
This is required to get it synced to hardware on boot, allowing the
lower levels of the page tables to be filled dynamically.
Link: http://lkml.kernel.org/r/20191031093909.9228-5-dja@axtens.net
Signed-off-by: Daniel Axtens <dja@axtens.net>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Axtens [Sun, 1 Dec 2019 01:54:57 +0000 (17:54 -0800)]
fork: support VMAP_STACK with KASAN_VMALLOC
Supporting VMAP_STACK with KASAN_VMALLOC is straightforward:
- clear the shadow region of vmapped stacks when swapping them in
- tweak Kconfig to allow VMAP_STACK to be turned on with KASAN
Link: http://lkml.kernel.org/r/20191031093909.9228-4-dja@axtens.net
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Axtens [Sun, 1 Dec 2019 01:54:53 +0000 (17:54 -0800)]
kasan: add test for vmalloc
Test kasan vmalloc support by adding a new test to the module.
Link: http://lkml.kernel.org/r/20191031093909.9228-3-dja@axtens.net
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Axtens [Sun, 1 Dec 2019 01:54:50 +0000 (17:54 -0800)]
kasan: support backing vmalloc space with real shadow memory
Patch series "kasan: support backing vmalloc space with real shadow
memory", v11.
Currently, vmalloc space is backed by the early shadow page. This means
that kasan is incompatible with VMAP_STACK.
This series provides a mechanism to back vmalloc space with real,
dynamically allocated memory. I have only wired up x86, because that's
the only currently supported arch I can work with easily, but it's very
easy to wire up other architectures, and it appears that there is some
work-in-progress code to do this on arm64 and s390.
This has been discussed before in the context of VMAP_STACK:
- https://bugzilla.kernel.org/show_bug.cgi?id=202009
- https://lkml.org/lkml/2018/7/22/198
- https://lkml.org/lkml/2019/7/19/822
In terms of implementation details:
Most mappings in vmalloc space are small, requiring less than a full
page of shadow space. Allocating a full shadow page per mapping would
therefore be wasteful. Furthermore, to ensure that different mappings
use different shadow pages, mappings would have to be aligned to
KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE.
Instead, share backing space across multiple mappings. Allocate a
backing page when a mapping in vmalloc space uses a particular page of
the shadow region. This page can be shared by other vmalloc mappings
later on.
We hook in to the vmap infrastructure to lazily clean up unused shadow
memory.
Testing with test_vmalloc.sh on an x86 VM with 2 vCPUs shows that:
- Turning on KASAN, inline instrumentation, without vmalloc, introuduces
a 4.1x-4.2x slowdown in vmalloc operations.
- Turning this on introduces the following slowdowns over KASAN:
* ~1.76x slower single-threaded (test_vmalloc.sh performance)
* ~2.18x slower when both cpus are performing operations
simultaneously (test_vmalloc.sh sequential_test_order=1)
This is unfortunate but given that this is a debug feature only, not the
end of the world. The benchmarks are also a stress-test for the vmalloc
subsystem: they're not indicative of an overall 2x slowdown!
This patch (of 4):
Hook into vmalloc and vmap, and dynamically allocate real shadow memory
to back the mappings.
Most mappings in vmalloc space are small, requiring less than a full
page of shadow space. Allocating a full shadow page per mapping would
therefore be wasteful. Furthermore, to ensure that different mappings
use different shadow pages, mappings would have to be aligned to
KASAN_SHADOW_SCALE_SIZE * PAGE_SIZE.
Instead, share backing space across multiple mappings. Allocate a
backing page when a mapping in vmalloc space uses a particular page of
the shadow region. This page can be shared by other vmalloc mappings
later on.
We hook in to the vmap infrastructure to lazily clean up unused shadow
memory.
To avoid the difficulties around swapping mappings around, this code
expects that the part of the shadow region that covers the vmalloc space
will not be covered by the early shadow page, but will be left unmapped.
This will require changes in arch-specific code.
This allows KASAN with VMAP_STACK, and may be helpful for architectures
that do not have a separate module space (e.g. powerpc64, which I am
currently working on). It also allows relaxing the module alignment
back to PAGE_SIZE.
Testing with test_vmalloc.sh on an x86 VM with 2 vCPUs shows that:
- Turning on KASAN, inline instrumentation, without vmalloc, introuduces
a 4.1x-4.2x slowdown in vmalloc operations.
- Turning this on introduces the following slowdowns over KASAN:
* ~1.76x slower single-threaded (test_vmalloc.sh performance)
* ~2.18x slower when both cpus are performing operations
simultaneously (test_vmalloc.sh sequential_test_order=3D1)
This is unfortunate but given that this is a debug feature only, not the
end of the world.
The full benchmark results are:
Performance
No KASAN KASAN original x baseline KASAN vmalloc x baseline x KASAN
fix_size_alloc_test 662004
11404956 17.23
19144610 28.92 1.68
full_fit_alloc_test 710950
12029752 16.92
13184651 18.55 1.10
long_busy_list_alloc_test
9431875 43990172 4.66
82970178 8.80 1.89
random_size_alloc_test
5033626 23061762 4.58
47158834 9.37 2.04
fix_align_alloc_test
1252514 15276910 12.20
31266116 24.96 2.05
random_size_align_alloc_te
1648501 14578321 8.84
25560052 15.51 1.75
align_shift_alloc_test 147 830 5.65 5692 38.72 6.86
pcpu_alloc_test 80732 125520 1.55 140864 1.74 1.12
Total Cycles
119240774314 763211341128 6.40
1390338696894 11.66 1.82
Sequential, 2 cpus
No KASAN KASAN original x baseline KASAN vmalloc x baseline x KASAN
fix_size_alloc_test
1423150 14276550 10.03
27733022 19.49 1.94
full_fit_alloc_test
1754219 14722640 8.39
15030786 8.57 1.02
long_busy_list_alloc_test
11451858 52154973 4.55
107016027 9.34 2.05
random_size_alloc_test
5989020 26735276 4.46
68885923 11.50 2.58
fix_align_alloc_test
2050976 20166900 9.83
50491675 24.62 2.50
random_size_align_alloc_te
2858229 17971700 6.29
38730225 13.55 2.16
align_shift_alloc_test 405 6428 15.87 26253 64.82 4.08
pcpu_alloc_test 127183 151464 1.19 216263 1.70 1.43
Total Cycles
54181269392 308723699764 5.70
650772566394 12.01 2.11
fix_size_alloc_test
1420404 14289308 10.06
27790035 19.56 1.94
full_fit_alloc_test
1736145 14806234 8.53
15274301 8.80 1.03
long_busy_list_alloc_test
11404638 52270785 4.58
107550254 9.43 2.06
random_size_alloc_test
6017006 26650625 4.43
68696127 11.42 2.58
fix_align_alloc_test
2045504 20280985 9.91
50414862 24.65 2.49
random_size_align_alloc_te
2845338 17931018 6.30
38510276 13.53 2.15
align_shift_alloc_test 472 3760 7.97 9656 20.46 2.57
pcpu_alloc_test 118643 132732 1.12 146504 1.23 1.10
Total Cycles
54040011688 309102805492 5.72
651325675652 12.05 2.11
[dja@axtens.net: fixups]
Link: http://lkml.kernel.org/r/20191120052719.7201-1-dja@axtens.net
Link: https://bugzilla.kernel.org/show_bug.cgi?id=3D202009
Link: http://lkml.kernel.org/r/20191031093909.9228-2-dja@axtens.net
Signed-off-by: Mark Rutland <mark.rutland@arm.com> [shadow rework]
Signed-off-by: Daniel Axtens <dja@axtens.net>
Co-developed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Uladzislau Rezki (Sony) [Sun, 1 Dec 2019 01:54:47 +0000 (17:54 -0800)]
mm/vmalloc: rework vmap_area_lock
With the new allocation approach introduced in the 5.2 kernel, it
becomes possible to get rid of one global spinlock. By doing that we
can further improve the KVA from the performance point of view.
Basically we can have two independent locks, one for allocation part and
another one for deallocation, because of two different entities: "free
data structures" and "busy data structures".
As a result, allocation/deallocation operations can still interfere
between each other in case of running simultaneously on different CPUs,
it means there is still dependency, but with two locks it becomes lower.
Summarizing:
- it reduces the high lock contention
- it allows to perform operations on "free" and "busy"
trees in parallel on different CPUs. Please note it
does not solve scalability issue.
Test results:
In order to evaluate this patch, we can run "vmalloc test driver" to see
how many CPU cycles it takes to complete all test cases running
sequentially. All online CPUs run it so it will cause a high lock
contention.
HiKey 960, ARM64, 8xCPUs, big.LITTLE:
<snip>
sudo ./test_vmalloc.sh sequential_test_order=1
<snip>
<default>
[ 390.950557] All test took CPU0=
457126382 cycles
[ 391.046690] All test took CPU1=
454763452 cycles
[ 391.128586] All test took CPU2=
454539334 cycles
[ 391.222669] All test took CPU3=
455649517 cycles
[ 391.313946] All test took CPU4=
388272196 cycles
[ 391.410425] All test took CPU5=
384036264 cycles
[ 391.492219] All test took CPU6=
387432964 cycles
[ 391.578433] All test took CPU7=
387201996 cycles
<default>
<patched>
[ 304.721224] All test took CPU0=
391521310 cycles
[ 304.821219] All test took CPU1=
393533002 cycles
[ 304.917120] All test took CPU2=
392243032 cycles
[ 305.008986] All test took CPU3=
392353853 cycles
[ 305.108944] All test took CPU4=
297630721 cycles
[ 305.196406] All test took CPU5=
297548736 cycles
[ 305.288602] All test took CPU6=
297092392 cycles
[ 305.381088] All test took CPU7=
297293597 cycles
<patched>
~14%-23% patched variant is better.
Link: http://lkml.kernel.org/r/20191022155800.20468-1-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Anders Roxell [Sun, 1 Dec 2019 01:54:43 +0000 (17:54 -0800)]
selftests: vm: add fragment CONFIG_TEST_VMALLOC
When running test_vmalloc.sh smoke the following print out states that
the fragment is missing.
# ./test_vmalloc.sh: You must have the following enabled in your kernel:
# CONFIG_TEST_VMALLOC=m
Rework to add the fragment 'CONFIG_TEST_VMALLOC=m' to the config file.
Link: http://lkml.kernel.org/r/20190916095217.19665-1-anders.roxell@linaro.org
Fixes:
a05ef00c9790 ("selftests/vm: add script helper for CONFIG_TEST_VMALLOC_MODULE")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Uladzislau Rezki (Sony) [Sun, 1 Dec 2019 01:54:40 +0000 (17:54 -0800)]
mm/vmalloc: add more comments to the adjust_va_to_fit_type()
When fit type is NE_FIT_TYPE there is a need in one extra object.
Usually the "ne_fit_preload_node" per-CPU variable has it and there is
no need in GFP_NOWAIT allocation, but there are exceptions.
This commit just adds more explanations, as a result giving answers on
questions like when it can occur, how often, under which conditions and
what happens if GFP_NOWAIT gets failed.
Link: http://lkml.kernel.org/r/20191016095438.12391-3-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Daniel Wagner <dwagner@suse.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Uladzislau Rezki <urezki@gmail.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Uladzislau Rezki (Sony) [Sun, 1 Dec 2019 01:54:37 +0000 (17:54 -0800)]
mm/vmalloc: respect passed gfp_mask when doing preloading
Allocation functions should comply with the given gfp_mask as much as
possible. The preallocation code in alloc_vmap_area doesn't follow that
pattern and it is using a hardcoded GFP_KERNEL. Although this doesn't
really make much difference because vmalloc is not GFP_NOWAIT compliant
in general (e.g. page table allocations are GFP_KERNEL) there is no
reason to spread that bad habit and it is good to fix the antipattern.
[mhocko@suse.com: rewrite changelog]
Link: http://lkml.kernel.org/r/20191016095438.12391-2-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Daniel Wagner <dwagner@suse.de>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Uladzislau Rezki (Sony) [Sun, 1 Dec 2019 01:54:33 +0000 (17:54 -0800)]
mm/vmalloc: remove preempt_disable/enable when doing preloading
Some background. The preemption was disabled before to guarantee that a
preloaded object is available for a CPU, it was stored for. That was
achieved by combining the disabling the preemption and taking the spin
lock while the ne_fit_preload_node is checked.
The aim was to not allocate in atomic context when spinlock is taken
later, for regular vmap allocations. But that approach conflicts with
CONFIG_PREEMPT_RT philosophy. It means that calling spin_lock() with
disabled preemption is forbidden in the CONFIG_PREEMPT_RT kernel.
Therefore, get rid of preempt_disable() and preempt_enable() when the
preload is done for splitting purpose. As a result we do not guarantee
now that a CPU is preloaded, instead we minimize the case when it is
not, with this change, by populating the per cpu preload pointer under
the vmap_area_lock.
This implies that at least each caller that has done the preallocation
will not fallback to an atomic allocation later. It is possible that
the preallocation would be pointless or that no preallocation is done
because of the race but the data shows that this is really rare.
For example i run the special test case that follows the preload pattern
and path. 20 "unbind" threads run it and each does
1000000 allocations.
Only 3.5 times among
1000000 a CPU was not preloaded. So it can happen
but the number is negligible.
[mhocko@suse.com: changelog additions]
Link: http://lkml.kernel.org/r/20191016095438.12391-1-urezki@gmail.com
Fixes:
82dd23e84be3 ("mm/vmalloc.c: preload a CPU with one object for split purpose")
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Daniel Wagner <dwagner@suse.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Liu Xiang [Sun, 1 Dec 2019 01:54:30 +0000 (17:54 -0800)]
mm/vmalloc.c: remove unnecessary highmem_mask from parameter of gfpflags_allow_blocking()
gfpflags_allow_blocking() does not care about __GFP_HIGHMEM, so
highmem_mask can be removed.
Link: http://lkml.kernel.org/r/1568812319-3467-1-git-send-email-liuxiang_1999@126.com
Signed-off-by: Liu Xiang <liuxiang_1999@126.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Sun, 1 Dec 2019 01:54:27 +0000 (17:54 -0800)]
mm/sparse.c: do not waste pre allocated memmap space
Vincent has noticed [1] that there is something unusual with the memmap
allocations going on on his platform
: I noticed this because on my ARM64 platform, with 1 GiB of memory the
: first [and only] section is allocated from the zeroing path while with
: 2 GiB of memory the first 1 GiB section is allocated from the
: non-zeroing path.
The underlying problem is that although sparse_buffer_init allocates
enough memory for all sections on the node sparse_buffer_alloc is not
able to consume them due to mismatch in the expected allocation
alignement. While sparse_buffer_init preallocation uses the PAGE_SIZE
alignment the real memmap has to be aligned to section_map_size() this
results in a wasted initial chunk of the preallocated memmap and
unnecessary fallback allocation for a section.
While we are at it also change __populate_section_memmap to align to the
requested size because at least VMEMMAP has constrains to have memmap
properly aligned.
[1] http://lkml.kernel.org/r/
20191030131122.8256-1-vincent.whitchurch@axis.com
[akpm@linux-foundation.org: tweak layout, per David]
Link: http://lkml.kernel.org/r/20191119092642.31799-1-mhocko@kernel.org
Fixes:
35fd1eb1e821 ("mm/sparse: abstract sparse buffer allocations")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Debugged-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Oscar Salvador <OSalvador@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ilya Leoshkevich [Sun, 1 Dec 2019 01:54:24 +0000 (17:54 -0800)]
mm/sparse.c: mark populate_section_memmap as __meminit
Building the kernel on s390 with -Og produces the following warning:
WARNING: vmlinux.o(.text+0x28dabe): Section mismatch in reference from the function populate_section_memmap() to the function .meminit.text:__populate_section_memmap()
The function populate_section_memmap() references
the function __meminit __populate_section_memmap().
This is often because populate_section_memmap lacks a __meminit
annotation or the annotation of __populate_section_memmap is wrong.
While -Og is not supported, in theory this might still happen with
another compiler or on another architecture. So fix this by using the
correct section annotations.
[iii@linux.ibm.com: v2]
Link: http://lkml.kernel.org/r/20191030151639.41486-1-iii@linux.ibm.com
Link: http://lkml.kernel.org/r/20191028165549.14478-1-iii@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Oscar Salvador <OSalvador@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vincent Whitchurch [Sun, 1 Dec 2019 01:54:20 +0000 (17:54 -0800)]
mm/sparse: consistently do not zero memmap
sparsemem without VMEMMAP has two allocation paths to allocate the
memory needed for its memmap (done in sparse_mem_map_populate()).
In one allocation path (sparse_buffer_alloc() succeeds), the memory is
not zeroed (since it was previously allocated with
memblock_alloc_try_nid_raw()).
In the other allocation path (sparse_buffer_alloc() fails and
sparse_mem_map_populate() falls back to memblock_alloc_try_nid()), the
memory is zeroed.
AFAICS this difference does not appear to be on purpose. If the code is
supposed to work with non-initialized memory (__init_single_page() takes
care of zeroing the struct pages which are actually used), we should
consistently not zero the memory, to avoid masking bugs.
( I noticed this because on my ARM64 platform, with 1 GiB of memory the
first [and only] section is allocated from the zeroing path while with
2 GiB of memory the first 1 GiB section is allocated from the
non-zeroing path. )
Michal:
"the main user visible problem is a memory wastage. The overal amount
of memory should be small. I wouldn't call it stable material."
Link: http://lkml.kernel.org/r/20191030131122.8256-1-vincent.whitchurch@axis.com
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Hildenbrand [Sun, 1 Dec 2019 01:54:17 +0000 (17:54 -0800)]
mm/memory_hotplug.c: don't allow to online/offline memory blocks with holes
Our onlining/offlining code is unnecessarily complicated. Only memory
blocks added during boot can have holes (a range that is not
IORESOURCE_SYSTEM_RAM). Hotplugged memory never has holes (e.g., see
add_memory_resource()). All memory blocks that belong to boot memory
are already online.
Note that boot memory can have holes and the memmap of the holes is
marked PG_reserved. However, also memory allocated early during boot is
PG_reserved - basically every page of boot memory that is not given to
the buddy is PG_reserved.
Therefore, when we stop allowing to offline memory blocks with holes, we
implicitly no longer have to deal with onlining memory blocks with
holes. E.g., online_pages() will do a walk_system_ram_range(...,
online_pages_range), whereby online_pages_range() will effectively only
free the memory holes not falling into a hole to the buddy. The other
pages (holes) are kept PG_reserved (via
move_pfn_range_to_zone()->memmap_init_zone()).
This allows to simplify the code. For example, we no longer have to
worry about marking pages that fall into memory holes PG_reserved when
onlining memory. We can stop setting pages PG_reserved completely in
memmap_init_zone().
Offlining memory blocks added during boot is usually not guaranteed to
work either way (unmovable data might have easily ended up on that
memory during boot). So stopping to do that should not really hurt.
Also, people are not even aware of a setup where onlining/offlining of
memory blocks with holes used to work reliably (see [1] and [2]
especially regarding the hotplug path) - I doubt it worked reliably.
For the use case of offlining memory to unplug DIMMs, we should see no
change. (holes on DIMMs would be weird).
Please note that hardware errors (PG_hwpoison) are not memory holes and
are not affected by this change when offlining.
[1] https://lkml.org/lkml/2019/10/22/135
[2] https://lkml.org/lkml/2019/8/14/1365
Link: http://lkml.kernel.org/r/20191119115237.6662-1-david@redhat.com
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Hildenbrand [Sun, 1 Dec 2019 01:54:14 +0000 (17:54 -0800)]
drivers/base/memory.c: drop the mem_sysfs_mutex
The mem_sysfs_mutex isn't really helpful. Also, it's not really clear
what the mutex protects at all.
The device lists of the memory subsystem are protected separately. We
don't need that mutex when looking up. creating, or removing
independent devices. find_memory_block_by_id() will perform locking on
its own and grab a reference of the returned device.
At the time memory_dev_init() is called, we cannot have concurrent
hot(un)plug operations yet - we're still fairly early during boot. We
don't need any locking.
The creation/removal of memory block devices should be protected on a
higher level - especially using the device hotplug lock to avoid
documented issues (see Documentation/core-api/memory-hotplug.rst) - or
if that is reworked, using similar locking.
Protecting in the context of these functions only doesn't really make
sense. Especially, if we would have a situation where the same memory
blocks are created/deleted at the same time, there is something horribly
going wrong (imagining adding/removing a DIMM at the same time from two
call paths) - after the functions succeeded something else in the
callers would blow up (e.g., create_memory_block_devices() succeeded but
there are no memory block devices anymore).
All relevant call paths (except when adding memory early during boot via
ACPI, which is now documented) hold the device hotplug lock when adding
memory, and when removing memory. Let's document that instead.
Add a simple safety net to create_memory_block_devices() in case we
would actually remove memory blocks while adding them, so we'll never
dereference a NULL pointer. Simplify memory_dev_init() now that the
lock is gone.
Link: http://lkml.kernel.org/r/20190925082621.4927-1-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ben Dooks (Codethink) [Sun, 1 Dec 2019 01:54:10 +0000 (17:54 -0800)]
include/linux/memory_hotplug.h: move definitions of {set,clear}_zone_contiguous
The {set,clear}_zone_contiguous are built whatever the configuratoon so
move the definitions outside the current ifdef to avoid the following
compiler warnings:
mm/page_alloc.c:1550:6: warning: no previous prototype for 'set_zone_contiguous' [-Wmissing-prototypes]
mm/page_alloc.c:1571:6: warning: no previous prototype for 'clear_zone_contiguous' [-Wmissing-prototypes]
Link: http://lkml.kernel.org/r/20191106123911.7435-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Hildenbrand [Sun, 1 Dec 2019 01:54:07 +0000 (17:54 -0800)]
mm/page_isolation.c: convert SKIP_HWPOISON to MEMORY_OFFLINE
We have two types of users of page isolation:
1. Memory offlining: Offline memory so it can be unplugged. Memory
won't be touched.
2. Memory allocation: Allocate memory (e.g., alloc_contig_range()) to
become the owner of the memory and make use of
it.
For example, in case we want to offline memory, we can ignore (skip
over) PageHWPoison() pages, as the memory won't get used. We can allow
to offline memory. In contrast, we don't want to allow to allocate such
memory.
Let's generalize the approach so we can special case other types of
pages we want to skip over in case we offline memory. While at it, also
pass the same flags to test_pages_isolated().
Link: http://lkml.kernel.org/r/20191021172353.3056-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Hildenbrand [Sun, 1 Dec 2019 01:54:03 +0000 (17:54 -0800)]
mm/page_alloc.c: don't set pages PageReserved() when offlining
Patch series "mm: Memory offlining + page isolation cleanups", v2.
This patch (of 2):
We call __offline_isolated_pages() from __offline_pages() after all
pages were isolated and are either free (PageBuddy()) or PageHWPoison.
Nothing can stop us from offlining memory at this point.
In __offline_isolated_pages() we first set all affected memory sections
offline (offline_mem_sections(pfn, end_pfn)), to mark the memmap as
invalid (pfn_to_online_page() will no longer succeed), and then walk
over all pages to pull the free pages from the free lists (to the
isolated free lists, to be precise).
Note that re-onlining a memory block will result in the whole memmap
getting reinitialized, overwriting any old state. We already poision
the memmap when offlining is complete to find any access to
stale/uninitialized memmaps.
So, setting the pages PageReserved() is not helpful. The memap is
marked offline and all pageblocks are isolated. As soon as offline, the
memmap is stale either way.
This looks like a leftover from ancient times where we initialized the
memmap when adding memory and not when onlining it (the pages were set
PageReserved so re-onling would work as expected).
Link: http://lkml.kernel.org/r/20191021172353.3056-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Pingfan Liu <kernelfans@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Hildenbrand [Sun, 1 Dec 2019 01:54:00 +0000 (17:54 -0800)]
mm/memory_hotplug: remove __online_page_free() and __online_page_increment_counters()
Let's drop the now unused functions.
Link: http://lkml.kernel.org/r/20190909114830.662-4-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Hildenbrand [Sun, 1 Dec 2019 01:53:55 +0000 (17:53 -0800)]
hv_balloon: use generic_online_page()
Let's use the generic onlining function - which will now also take care
of calling kernel_map_pages().
Link: http://lkml.kernel.org/r/20190909114830.662-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Hildenbrand [Sun, 1 Dec 2019 01:53:51 +0000 (17:53 -0800)]
mm/memory_hotplug: export generic_online_page()
Patch series "mm/memory_hotplug: Export generic_online_page()".
Let's replace the __online_page...() functions by generic_online_page().
Hyper-V only wants to delay the actual onlining of un-backed pages, so
we can simpy re-use the generic function.
This patch (of 3):
Let's expose generic_online_page() so online_page_callback users can
simply fall back to the generic implementation when actually deciding to
online the pages.
Link: http://lkml.kernel.org/r/20190909114830.662-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alastair D'Silva [Sun, 1 Dec 2019 01:53:48 +0000 (17:53 -0800)]
mm/memory_hotplug.c: add a bounds check to __add_pages()
On PowerPC, the address ranges allocated to OpenCAPI LPC memory are
allocated from firmware. These address ranges may be higher than what
older kernels permit, as we increased the maximum permissable address in
commit
4ffe713b7587 ("powerpc/mm: Increase the max addressable memory to
2PB"). It is possible that the addressable range may change again in
the future.
In this scenario, we end up with a bogus section returned from
__section_nr (see the discussion on the thread "mm: Trigger bug on if a
section is not found in __section_nr").
Adding a check here means that we fail early and have an opportunity to
handle the error gracefully, rather than rumbling on and potentially
accessing an incorrect section.
Further discussion is also on the thread ("powerpc: Perform a bounds
check in arch_add_memory")
http://lkml.kernel.org/r/
20190827052047.31547-1-alastair@au1.ibm.com
Link: http://lkml.kernel.org/r/20191001004617.7536-2-alastair@au1.ibm.com
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Anshuman Khandual [Sun, 1 Dec 2019 01:53:44 +0000 (17:53 -0800)]
mm/hotplug: reorder memblock_[free|remove]() calls in try_remove_memory()
Currently during memory hot add procedure, memory gets into memblock
before calling arch_add_memory() which creates its linear mapping.
add_memory_resource() {
..................
memblock_add_node()
..................
arch_add_memory()
..................
}
But during memory hot remove procedure, removal from memblock happens
first before its linear mapping gets teared down with
arch_remove_memory() which is not consistent. Resource removal should
happen in reverse order as they were added. However this does not pose
any problem for now, unless there is an assumption regarding linear
mapping. One example was a subtle failure on arm64 platform [1].
Though this has now found a different solution.
try_remove_memory() {
..................
memblock_free()
memblock_remove()
..................
arch_remove_memory()
..................
}
This changes the sequence of resource removal including memblock and
linear mapping tear down during memory hot remove which will now be the
reverse order in which they were added during memory hot add. The
changed removal order looks like the following.
try_remove_memory() {
..................
arch_remove_memory()
..................
memblock_free()
memblock_remove()
..................
}
[1] https://patchwork.kernel.org/patch/
11127623/
Memory hot remove now works on arm64 without this because a recent
commit
60bb462fc7ad ("drivers/base/node.c: simplify
unregister_memory_block_under_nodes()").
This does not fix a serious problem. It just removes an inconsistency
while freeing resources during memory hot remove which for now does not
pose a real problem.
David mentioned that re-ordering should still make sense for consistency
purpose (removing stuff in the reverse order they were added). This
patch is now detached from arm64 hot-remove series.
Michal:
: I would just a note that the inconsistency doesn't pose any problem now
: but if somebody makes any assumptions about linear mappings then it could
: get subtly broken like your example for arm64 which has found a different
: solution in the meantime.
Link: http://lkml.kernel.org/r/1569380273-7708-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yunfeng Ye [Sun, 1 Dec 2019 01:53:41 +0000 (17:53 -0800)]
mm/memory-failure.c: use page_shift() in add_to_kill()
page_shift() is supported after the commit
94ad9338109f ("mm: introduce
page_shift()").
So replace with page_shift() in add_to_kill() for readability.
Link: http://lkml.kernel.org/r/543d8bc9-f2e7-3023-7c35-2e7ed67c0e82@huawei.com
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Naoya Horiguchi [Sun, 1 Dec 2019 01:53:38 +0000 (17:53 -0800)]
mm, soft-offline: convert parameter to pfn
Currently soft_offline_page() receives struct page, and its sibling
memory_failure() receives pfn. This discrepancy looks weird and makes
precheck on pfn validity tricky. So let's align them.
Link: http://lkml.kernel.org/r/20191016234706.GA5493@www9186uo.sakura.ne.jp
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jane Chu [Sun, 1 Dec 2019 01:53:35 +0000 (17:53 -0800)]
mm/memory-failure.c clean up around tk pre-allocation
add_to_kill() expects the first 'tk' to be pre-allocated, it makes
subsequent allocations on need basis, this makes the code a bit
difficult to read.
Move all the allocation internal to add_to_kill() and drop the **tk
argument.
Link: http://lkml.kernel.org/r/1565112345-28754-2-git-send-email-jane.chu@oracle.com
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joel Fernandes (Google) [Sun, 1 Dec 2019 01:53:31 +0000 (17:53 -0800)]
memfd: add test for COW on MAP_PRIVATE and F_SEAL_FUTURE_WRITE mappings
In this test, the parent and child both have writable private mappings.
The test shows that without the patch in this series, the parent and
child shared the same memory which is incorrect. In other words, COW
needs to be triggered so any writes to child's copy stays local to the
child.
Link: http://lkml.kernel.org/r/20191107195355.80608-2-joel@joelfernandes.org
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Nicolas Geoffray <ngeoffray@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nicolas Geoffray [Sun, 1 Dec 2019 01:53:28 +0000 (17:53 -0800)]
mm, memfd: fix COW issue on MAP_PRIVATE and F_SEAL_FUTURE_WRITE mappings
F_SEAL_FUTURE_WRITE has unexpected behavior when used with MAP_PRIVATE:
A private mapping created after the memfd file that gets sealed with
F_SEAL_FUTURE_WRITE loses the copy-on-write at fork behavior, meaning
children and parent share the same memory, even though the mapping is
private.
The reason for this is due to the code below:
static int shmem_mmap(struct file *file, struct vm_area_struct *vma)
{
struct shmem_inode_info *info = SHMEM_I(file_inode(file));
if (info->seals & F_SEAL_FUTURE_WRITE) {
/*
* New PROT_WRITE and MAP_SHARED mmaps are not allowed when
* "future write" seal active.
*/
if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE))
return -EPERM;
/*
* Since the F_SEAL_FUTURE_WRITE seals allow for a MAP_SHARED
* read-only mapping, take care to not allow mprotect to revert
* protections.
*/
vma->vm_flags &= ~(VM_MAYWRITE);
}
...
}
And for the mm to know if a mapping is copy-on-write:
static inline bool is_cow_mapping(vm_flags_t flags)
{
return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE;
}
The patch fixes the issue by making the mprotect revert protection
happen only for shared mappings. For private mappings, using mprotect
will have no effect on the seal behavior.
The F_SEAL_FUTURE_WRITE feature was introduced in v5.1 so v5.3.x stable
kernels would need a backport.
[akpm@linux-foundation.org: reflow comment, per Christoph]
Link: http://lkml.kernel.org/r/20191107195355.80608-1-joel@joelfernandes.org
Fixes:
ab3948f58ff84 ("mm/memfd: add an F_SEAL_FUTURE_WRITE seal to memfd")
Signed-off-by: Nicolas Geoffray <ngeoffray@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thomas Hellstrom [Sun, 1 Dec 2019 01:51:32 +0000 (17:51 -0800)]
mm/memory.c: fix a huge pud insertion race during faulting
A huge pud page can theoretically be faulted in racing with pmd_alloc()
in __handle_mm_fault(). That will lead to pmd_alloc() returning an
invalid pmd pointer.
Fix this by adding a pud_trans_unstable() function similar to
pmd_trans_unstable() and check whether the pud is really stable before
using the pmd pointer.
Race:
Thread 1: Thread 2: Comment
create_huge_pud() Fallback - not taken.
create_huge_pud() Taken.
pmd_alloc() Returns an invalid pointer.
This will result in user-visible huge page data corruption.
Note that this was caught during a code audit rather than a real
experienced problem. It looks to me like the only implementation that
currently creates huge pud pagetable entries is dev_dax_huge_fault()
which doesn't appear to care much about private (COW) mappings or
write-tracking which is, I believe, a prerequisite for create_huge_pud()
falling back on thread 1, but not in thread 2.
Link: http://lkml.kernel.org/r/20191115115808.21181-2-thomas_os@shipmail.org
Fixes:
a00cc7d9dd93 ("mm, x86: add support for PUD-sized transparent hugepages")
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thomas Hellstrom [Sun, 1 Dec 2019 01:51:29 +0000 (17:51 -0800)]
mm: move the backup x_devmap() functions to asm-generic/pgtable.h
The asm-generic/pgtable.h include file appears to be the correct place for
the backup x_devmap() inline functions. Moving them here is also
necessary if we want to include x_devmap() in the [pmd|pud]_unstable
functions. So move the x_devmap() functions to asm-generic/pgtable.h
Link: http://lkml.kernel.org/r/20191115115808.21181-1-thomas_os@shipmail.org
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yang Shi [Sun, 1 Dec 2019 01:51:26 +0000 (17:51 -0800)]
mm/rmap.c: use VM_BUG_ON_PAGE() in __page_check_anon_rmap()
The __page_check_anon_rmap() just calls two BUG_ON()s protected by
CONFIG_DEBUG_VM, the #ifdef could be eliminated by using VM_BUG_ON_PAGE().
Link: http://lkml.kernel.org/r/1573157346-111316-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miles Chen [Sun, 1 Dec 2019 01:51:23 +0000 (17:51 -0800)]
mm/rmap.c: fix outdated comment in page_get_anon_vma()
Replace DESTROY_BY_RCU with SLAB_TYPESAFE_BY_RCU because
SLAB_DESTROY_BY_RCU has been renamed to SLAB_TYPESAFE_BY_RCU by commit
5f0d5a3ae7cf ("mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU")
Link: http://lkml.kernel.org/r/20191017093554.22562-1-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vineet Gupta [Sun, 1 Dec 2019 01:51:20 +0000 (17:51 -0800)]
asm-generic/mm: stub out p{4,u}d_clear_bad() if __PAGETABLE_P{4,U}D_FOLDED
This came up when removing __ARCH_HAS_5LEVEL_HACK for ARC as code bloat.
With this patch we see the following code reduction.
| bloat-o-meter2 vmlinux-D-elide-p4d_free_tlb vmlinux-E-elide-p?d_clear_bad
| add/remove: 0/2 grow/shrink: 0/0 up/down: 0/-40 (-40)
| function old new delta
| pud_clear_bad 20 - -20
| p4d_clear_bad 20 - -20
| Total: Before=
4136930, After=
4136890, chg -1.000000%
Link: http://lkml.kernel.org/r/20191016162400.14796-6-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Will Deacon <will@kernel.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vineet Gupta [Sun, 1 Dec 2019 01:51:16 +0000 (17:51 -0800)]
asm-generic/tlb: stub out pmd_free_tlb() if nopmd
This came up when removing __ARCH_HAS_5LEVEL_HACK for ARC as code bloat.
With this patch we see the following code reduction.
| bloat-o-meter2 vmlinux-E-elide-p?d_clear_bad vmlinux-F-elide-pmd_free_tlb
| add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-112 (-112)
| function old new delta
| free_pgd_range 422 310 -112
| Total: Before=
4137042, After=
4136930, chg -1.000000%
Note that pmd folding can be tricky: In 2-level setup (where pmd is
conceptually folded) most pmd routines are valid and refer to upper levels.
In this patch we can, but see next patch for example where we can't
Link: http://lkml.kernel.org/r/20191016162400.14796-5-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vineet Gupta [Sun, 1 Dec 2019 01:51:13 +0000 (17:51 -0800)]
asm-generic/tlb: stub out p4d_free_tlb() if nop4d ...
... independent of __ARCH_HAS_5LEVEL_HACK
This came up when removing __ARCH_HAS_5LEVEL_HACK for ARC as code bloat.
With this patch we see the following code reduction
| bloat-o-meter2 vmlinux-C-elide-pud_free_tlb vmlinux-D-elide-p4d_free_tlb
| add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-104 (-104)
| function old new delta
| free_pgd_range 552 422 -130
| Total: Before=
4137172, After=
4137042, chg -1.000000%
Link: http://lkml.kernel.org/r/20191016162400.14796-4-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vineet Gupta [Sun, 1 Dec 2019 01:51:10 +0000 (17:51 -0800)]
asm-generic/tlb: stub out pud_free_tlb() if nopud ...
... independent of __ARCH_HAS_4LEVEL_HACK
This came up when removing __ARCH_HAS_5LEVEL_HACK for ARC as code bloat.
With this patch we see the following code reduction
| bloat-o-meter2 vmlinux-B-elide-ARCH_USE_5LEVEL_HACK vmlinux-C-elide-pud_free_tlb
| add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-104 (-104)
| function old new delta
| free_pgd_range 656 552 -104
| Total: Before=
4137276, After=
4137172, chg -1.000000%
Note: The primary change is alternate defintion for pud_free_tlb() but
while there also removed empty stubs for __pud_free_tlb, which is anyhow
called only from pud_free_tlb()
Link: http://lkml.kernel.org/r/20191016162400.14796-3-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vineet Gupta [Sun, 1 Dec 2019 01:51:06 +0000 (17:51 -0800)]
ARC: mm: remove __ARCH_USE_5LEVEL_HACK
Patch series "elide extraneous generated code for folded p4d/pud/pmd", v3.
This series came out of seemingly benign excursion into
understanding/removing __ARCH_USE_5LEVEL_HACK from ARC port showing some
extraneous code being generated despite folded p4d/pud/pmd
| bloat-o-meter2 vmlinux-[AB]*
| add/remove: 0/0 grow/shrink: 3/0 up/down: 130/0 (130)
| function old new delta
| free_pgd_range 548 660 +112
| p4d_clear_bad 2 20 +18
The patches here address that
| bloat-o-meter2 vmlinux-[BF]*
| add/remove: 0/2 grow/shrink: 0/1 up/down: 0/-386 (-386)
| function old new delta
| pud_clear_bad 20 - -20
| p4d_clear_bad 20 - -20
| free_pgd_range 660 314 -346
The code savings are not a whole lot, but still worthwhile IMHO.
This patch (of 5):
With paging code made 5-level compliant, this is no longer needed. ARC
has software page walker with 2 lookup levels (pgd -> pte)
This was expected to be non functional change but ended with slight
code bloat due to needless inclusions of p*d_free_tlb() macros which
will be addressed in further patches.
| bloat-o-meter2 vmlinux-[AB]*
| add/remove: 0/0 grow/shrink: 2/0 up/down: 128/0 (128)
| function old new delta
| free_pgd_range 546 656 +110
| p4d_clear_bad 2 20 +18
| Total: Before=
4137148, After=
4137276, chg 0.000000%
Link: http://lkml.kernel.org/r/20191016162400.14796-2-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Gaowei Pu [Sun, 1 Dec 2019 01:51:03 +0000 (17:51 -0800)]
mm/mmap.c: use IS_ERR_VALUE to check return value of get_unmapped_area
get_unmapped_area() returns an address or -errno on failure. Historically
we have checked for the failure by offset_in_page() which is correct but
quite hard to read. Newer code started using IS_ERR_VALUE which is much
easier to read. Convert remaining users of offset_in_page as well.
[mhocko@suse.com: rewrite changelog]
[mhocko@kernel.org: fix mremap.c and uprobes.c sites also]
Link: http://lkml.kernel.org/r/20191012102512.28051-1-pugaowei@gmail.com
Signed-off-by: Gaowei Pu <pugaowei@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Sun, 1 Dec 2019 01:50:59 +0000 (17:50 -0800)]
mm/rmap.c: reuse mergeable anon_vma as parent when fork
In __anon_vma_prepare(), we will try to find anon_vma if it is possible to
reuse it. While on fork, the logic is different.
Since commit
5beb49305251 ("mm: change anon_vma linking to fix
multi-process server scalability issue"), function anon_vma_clone() tries
to allocate new anon_vma for child process. But the logic here will
allocate a new anon_vma for each vma, even in parent this vma is mergeable
and share the same anon_vma with its sibling. This may do better for
scalability issue, while it is not necessary to do so especially after
interval tree is used.
Commit
7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
tries to reuse some anon_vma by counting child anon_vma and attached vmas.
While for those mergeable anon_vmas, we can just reuse it and not
necessary to go through the logic.
After this change, kernel build test reduces 20% anon_vma allocation.
Do the same kernel build test, it shows run time in sys reduced 11.6%.
Origin:
real 2m50.467s
user 17m52.002s
sys 1m51.953s
real 2m48.662s
user 17m55.464s
sys 1m50.553s
real 2m51.143s
user 17m59.687s
sys 1m53.600s
Patched:
real 2m39.933s
user 17m1.835s
sys 1m38.802s
real 2m39.321s
user 17m1.634s
sys 1m39.206s
real 2m39.575s
user 17m1.420s
sys 1m38.845s
Link: http://lkml.kernel.org/r/20191011072256.16275-2-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Sun, 1 Dec 2019 01:50:56 +0000 (17:50 -0800)]
mm/rmap.c: don't reuse anon_vma if we just want a copy
Before commit
7a3ef208e662 ("mm: prevent endless growth of anon_vma
hierarchy"), anon_vma_clone() doesn't change dst->anon_vma. While after
this commit, anon_vma_clone() will try to reuse an exist one on forking.
But this commit go a little bit further for the case not forking.
anon_vma_clone() is called from __vma_split(), __split_vma(), copy_vma()
and anon_vma_fork(). For the first three places, the purpose here is
get a copy of src and we don't expect to touch dst->anon_vma even it is
NULL.
While after that commit, it is possible to reuse an anon_vma when
dst->anon_vma is NULL. This is not we intend to have.
This patch stops reuse of anon_vma for non-fork cases.
Link: http://lkml.kernel.org/r/20191011072256.16275-1-richardw.yang@linux.intel.com
Fixes:
7a3ef208e662 ("mm: prevent endless growth of anon_vma hierarchy")
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Sun, 1 Dec 2019 01:50:53 +0000 (17:50 -0800)]
mm/mmap.c: rb_parent is not necessary in __vma_link_list()
Now we use rb_parent to get next, while this is not necessary.
When prev is NULL, this means vma should be the first element in the list.
Then next should be current first one (mm->mmap), no matter whether we
have parent or not.
After removing it, the code shows the beauty of symmetry.
Link: http://lkml.kernel.org/r/20190813032656.16625-1-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Sun, 1 Dec 2019 01:50:49 +0000 (17:50 -0800)]
mm/mmap.c: extract __vma_unlink_list() as counterpart for __vma_link_list()
Just make the code a little easier to read.
Link: http://lkml.kernel.org/r/20191006012636.31521-3-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Sun, 1 Dec 2019 01:50:46 +0000 (17:50 -0800)]
mm/mmap.c: __vma_unlink_prev() is not necessary now
The third parameter of __vma_unlink_common() could differentiate these two
types. __vma_unlink_prev() is not necessary now.
Link: http://lkml.kernel.org/r/20191006012636.31521-2-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Sun, 1 Dec 2019 01:50:43 +0000 (17:50 -0800)]
mm/mmap.c: prev could be retrieved from vma->vm_prev
Currently __vma_unlink_common handles two cases:
* has_prev
* or not
When has_prev is false, it is obvious prev is calculated from
vma->vm_prev in __vma_unlink_common.
When has_prev is true, the prev is passed through from __vma_unlink_prev
in __vma_adjust for non-case 8. And at the beginning next is calculated
from vma->vm_next, which implies vma is next->vm_prev.
The above statement sounds a little complicated, while to think in
another point of view, no matter whether vma and next is swapped, the
mmap link list still preserves its property. It is proper to access
vma->vm_prev.
Link: http://lkml.kernel.org/r/20191006012636.31521-1-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Konstantin Khlebnikov [Sun, 1 Dec 2019 01:50:40 +0000 (17:50 -0800)]
mm/swap.c: piggyback lru_add_drain_all() calls
This is a very slow operation. Right now POSIX_FADV_DONTNEED is the top
user because it has to freeze page references when removing it from the
cache. invalidate_bdev() calls it for the same reason. Both are
triggered from userspace, so it's easy to generate a storm.
mlock/mlockall no longer calls lru_add_drain_all - I've seen here
serious slowdown on older kernels.
There are some less obvious paths in memory migration/CMA/offlining
which shouldn't call frequently.
The worst case requires a non-trivial workload because
lru_add_drain_all() skips cpus where vectors are empty. Something must
constantly generate a flow of pages for each cpu. Also cpus must be
busy to make scheduling per-cpu works slower. And the machine must be
big enough (64+ cpus in our case).
In our case that was a massive series of mlock calls in map-reduce while
other tasks write logs (and generates flows of new pages in per-cpu
vectors). Mlock calls were serialized by mutex and accumulated latency
up to 10 seconds or more.
The kernel does not call lru_add_drain_all on mlock paths since 4.15,
but the same scenario could be triggered by fadvise(POSIX_FADV_DONTNEED)
or any other remaining user.
There is no reason to do the drain again if somebody else already
drained all the per-cpu vectors while we waited for the lock.
Piggyback on a drain starting and finishing while we wait for the lock:
all pages pending at the time of our entry were drained from the
vectors.
Callers like POSIX_FADV_DONTNEED retry their operations once after
draining per-cpu vectors when pages have unexpected references.
Link: http://lkml.kernel.org/r/157019456205.3142.3369423180908482020.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wei Yang [Sun, 1 Dec 2019 01:50:37 +0000 (17:50 -0800)]
mm/mmap.c: remove a never-triggered warning in __vma_adjust()
The upper level of "if" makes sure (end >= next->vm_end), which means
there are only two possibilities:
1) end == next->vm_end
2) end > next->vm_end
remove_next is assigned to be (1 + end > next->vm_end). This means if
remove_next is 1, end must equal to next->vm_end.
The VM_WARN_ON will never trigger.
Link: http://lkml.kernel.org/r/20190912063126.13250-1-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joel Fernandes (Google) [Sun, 1 Dec 2019 01:50:33 +0000 (17:50 -0800)]
rss_stat: add support to detect RSS updates of external mm
When a process updates the RSS of a different process, the rss_stat
tracepoint appears in the context of the process doing the update. This
can confuse userspace that the RSS of process doing the update is
updated, while in reality a different process's RSS was updated.
This issue happens in reclaim paths such as with direct reclaim or
background reclaim.
This patch adds more information to the tracepoint about whether the mm
being updated belongs to the current process's context (curr field). We
also include a hash of the mm pointer so that the process who the mm
belongs to can be uniquely identified (mm_id field).
Also vsprintf.c is refactored a bit to allow reuse of hashing code.
[akpm@linux-foundation.org: remove unused local `str']
[joelaf@google.com: inline call to ptr_to_hashval]
Link: http://lore.kernel.org/r/20191113153816.14b95acd@gandalf.local.home
Link: http://lkml.kernel.org/r/20191114164622.GC233237@google.com
Link: http://lkml.kernel.org/r/20191106024452.81923-1-joel@joelfernandes.org
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reported-by: Ioannis Ilkos <ilkos@google.com>
Acked-by: Petr Mladek <pmladek@suse.com> [lib/vsprintf.c]
Cc: Tim Murray <timmurray@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Carmen Jackson <carmenjackson@google.com>
Cc: Mayank Gupta <mayankgupta@google.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joel Fernandes (Google) [Sun, 1 Dec 2019 01:50:30 +0000 (17:50 -0800)]
mm: emit tracepoint when RSS changes
Useful to track how RSS is changing per TGID to detect spikes in RSS and
memory hogs. Several Android teams have been using this patch in
various kernel trees for half a year now. Many reported to me it is
really useful so I'm posting it upstream.
Initial patch developed by Tim Murray. Changes I made from original
patch: o Prevent any additional space consumed by mm_struct.
Regarding the fact that the RSS may change too often thus flooding the
traces - note that, there is some "hysterisis" with this already. That
is - We update the counter only if we receive 64 page faults due to
SPLIT_RSS_ACCOUNTING. However, during zapping or copying of pte range,
the RSS is updated immediately which can become noisy/flooding. In a
previous discussion, we agreed that BPF or ftrace can be used to rate
limit the signal if this becomes an issue.
Also note that I added wrappers to trace_rss_stat to prevent compiler
errors where linux/mm.h is included from tracing code, causing errors
such as:
CC kernel/trace/power-traces.o
In file included from ./include/trace/define_trace.h:102,
from ./include/trace/events/kmem.h:342,
from ./include/linux/mm.h:31,
from ./include/linux/ring_buffer.h:5,
from ./include/linux/trace_events.h:6,
from ./include/trace/events/power.h:12,
from kernel/trace/power-traces.c:15:
./include/trace/trace_events.h:113:22: error: field `ent' has incomplete type
struct trace_entry ent; \
Link: http://lore.kernel.org/r/20190903200905.198642-1-joel@joelfernandes.org
Link: http://lkml.kernel.org/r/20191001172817.234886-1-joel@joelfernandes.org
Co-developed-by: Tim Murray <timmurray@google.com>
Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Carmen Jackson <carmenjackson@google.com>
Cc: Mayank Gupta <mayankgupta@google.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Sun, 1 Dec 2019 01:50:26 +0000 (17:50 -0800)]
shmem: pin the file in shmem_fault() if mmap_sem is dropped
syzbot found the following crash:
BUG: KASAN: use-after-free in perf_trace_lock_acquire+0x401/0x530 include/trace/events/lock.h:13
Read of size 8 at addr
ffff8880a5cf2c50 by task syz-executor.0/26173
CPU: 0 PID: 26173 Comm: syz-executor.0 Not tainted 5.3.0-rc6 #146
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
perf_trace_lock_acquire+0x401/0x530 include/trace/events/lock.h:13
trace_lock_acquire include/trace/events/lock.h:13 [inline]
lock_acquire+0x2de/0x410 kernel/locking/lockdep.c:4411
__raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
_raw_spin_lock+0x2f/0x40 kernel/locking/spinlock.c:151
spin_lock include/linux/spinlock.h:338 [inline]
shmem_fault+0x5ec/0x7b0 mm/shmem.c:2034
__do_fault+0x111/0x540 mm/memory.c:3083
do_shared_fault mm/memory.c:3535 [inline]
do_fault mm/memory.c:3613 [inline]
handle_pte_fault mm/memory.c:3840 [inline]
__handle_mm_fault+0x2adf/0x3f20 mm/memory.c:3964
handle_mm_fault+0x1b5/0x6b0 mm/memory.c:4001
do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
__do_page_fault+0x536/0xdd0 arch/x86/mm/fault.c:1506
do_page_fault+0x38/0x590 arch/x86/mm/fault.c:1530
page_fault+0x39/0x40 arch/x86/entry/entry_64.S:1202
It happens if the VMA got unmapped under us while we dropped mmap_sem
and inode got freed.
Pinning the file if we drop mmap_sem fixes the issue.
Link: http://lkml.kernel.org/r/20190927083908.rhifa4mmaxefc24r@box
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: syzbot+03ee87124ee05af991bd@syzkaller.appspotmail.com
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:50:22 +0000 (17:50 -0800)]
mm: drop mmap_sem before calling balance_dirty_pages() in write fault
One of our services is observing hanging ps/top/etc under heavy write
IO, and the task states show this is an mmap_sem priority inversion:
A write fault is holding the mmap_sem in read-mode and waiting for
(heavily cgroup-limited) IO in balance_dirty_pages():
balance_dirty_pages+0x724/0x905
balance_dirty_pages_ratelimited+0x254/0x390
fault_dirty_shared_page.isra.96+0x4a/0x90
do_wp_page+0x33e/0x400
__handle_mm_fault+0x6f0/0xfa0
handle_mm_fault+0xe4/0x200
__do_page_fault+0x22b/0x4a0
page_fault+0x45/0x50
Somebody tries to change the address space, contending for the mmap_sem in
write-mode:
call_rwsem_down_write_failed_killable+0x13/0x20
do_mprotect_pkey+0xa8/0x330
SyS_mprotect+0xf/0x20
do_syscall_64+0x5b/0x100
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
The waiting writer locks out all subsequent readers to avoid lock
starvation, and several threads can be seen hanging like this:
call_rwsem_down_read_failed+0x14/0x30
proc_pid_cmdline_read+0xa0/0x480
__vfs_read+0x23/0x140
vfs_read+0x87/0x130
SyS_read+0x42/0x90
do_syscall_64+0x5b/0x100
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
To fix this, do what we do for cache read faults already: drop the
mmap_sem before calling into anything IO bound, in this case the
balance_dirty_pages() function, and return VM_FAULT_RETRY.
Link: http://lkml.kernel.org/r/20190924194238.GA29030@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chris Down [Sun, 1 Dec 2019 01:50:19 +0000 (17:50 -0800)]
Documentation/admin-guide/cgroup-v2.rst: document why inactive_X + active_X may not equal X
This has confused a significant number of people using cgroups inside
Facebook, and some of those outside as well judging by posts like
this[0] (although it's not a problem unique to cgroup v2).
If shmem handling in particular becomes more coherent at some point in
the future -- although that seems unlikely now -- we can change the
wording here.
[0]: https://unix.stackexchange.com/q/525092/10762
Link: http://lkml.kernel.org/r/20191111144958.GA11914@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Shakeel Butt [Sun, 1 Dec 2019 01:50:16 +0000 (17:50 -0800)]
mm: vmscan: memcontrol: remove mem_cgroup_select_victim_node()
Since commit
1ba6fc9af35b ("mm: vmscan: do not share cgroup iteration
between reclaimers"), the memcg reclaim does not bail out earlier based
on sc->nr_reclaimed and will traverse all the nodes. All the
reclaimable pages of the memcg on all the nodes will be scanned relative
to the reclaim priority. So, there is no need to maintain state
regarding which node to start the memcg reclaim from.
This patch effectively reverts the commit
889976dbcb12 ("memcg: reclaim
memory from nodes in round-robin order") and commit
453a9bf347f1
("memcg: fix numa scan information update to be triggered by memory
event").
[shakeelb@google.com: v2]
Link: http://lkml.kernel.org/r/20191030204232.139424-1-shakeelb@google.com
Link: http://lkml.kernel.org/r/20191029234753.224143-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hao Lee [Sun, 1 Dec 2019 01:50:12 +0000 (17:50 -0800)]
include/linux/memcontrol.h: fix comments based on per-node memcg
These comments should be updated as memcg limit enforcement has been
moved from zones to nodes.
Link: http://lkml.kernel.org/r/20191022150618.GA15519@haolee.github.io
Signed-off-by: Hao Lee <haolee.swjtu@gmail.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:50:09 +0000 (17:50 -0800)]
mm: memcontrol: try harder to set a new memory.high
Setting a memory.high limit below the usage makes almost no effort to
shrink the cgroup to the new target size.
While memory.high is a "soft" limit that isn't supposed to cause OOM
situations, we should still try harder to meet a user request through
persistent reclaim.
For example, after setting a 10M memory.high on an 800M cgroup full of
file cache, the usage shrinks to about 350M:
+ cat /cgroup/workingset/memory.current
841568256
+ echo 10M
+ cat /cgroup/workingset/memory.current
355729408
This isn't exactly what the user would expect to happen. Setting the
value a few more times eventually whittles the usage down to what we
are asking for:
+ echo 10M
+ cat /cgroup/workingset/memory.current
104181760
+ echo 10M
+ cat /cgroup/workingset/memory.current
31801344
+ echo 10M
+ cat /cgroup/workingset/memory.current
10440704
To improve this, add reclaim retry loops to the memory.high write()
callback, similar to what we do for memory.max, to make a reasonable
effort that the usage meets the requested size after the call returns.
Afterwards, a single write() to memory.high is enough in all but extreme
cases:
+ cat /cgroup/workingset/memory.current
841609216
+ echo 10M
+ cat /cgroup/workingset/memory.current
10182656
790M is not a reasonable reclaim target to ask of a single reclaim
invocation. And it wouldn't be reasonable to optimize the reclaim code
for it. So asking for the full size but retrying is not a bad choice
here: we express our intent, and benefit if reclaim becomes better at
handling larger requests, but we also acknowledge that some of the
deltas we can encounter in memory_high_write() are just too ridiculously
big for a single reclaim invocation to manage.
Link: http://lkml.kernel.org/r/20191022201518.341216-2-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Sun, 1 Dec 2019 01:50:06 +0000 (17:50 -0800)]
mm: memcontrol: remove dead code from memory_max_write()
When the reclaim loop in memory_max_write() is ^C'd or similar, we set err
to -EINTR. But we don't return err. Once the limit is set, we always
return success (nbytes). Delete the dead code.
Link: http://lkml.kernel.org/r/20191022201518.341216-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yafang Shao [Sun, 1 Dec 2019 01:50:03 +0000 (17:50 -0800)]
mm, memcg: clean up reclaim iter array
The mem_cgroup_reclaim_cookie is only used in memcg softlimit reclaim now,
and the priority of the reclaim is always 0. We don't need to define the
iter in struct mem_cgroup_per_node as an array any more. That could make
the code more clear and save some space.
Link: http://lkml.kernel.org/r/1569897728-1686-1-git-send-email-laoar.shao@gmail.com
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fengguang Wu [Sun, 1 Dec 2019 01:50:00 +0000 (17:50 -0800)]
mm/swap.c: trivial mark_page_accessed() cleanup
This avoids duplicated PageReferenced() calls. No behavior change.
Link: http://lkml.kernel.org/r/20191016225326.GB12497@wfg-t540p.sh.intel.com
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Liu Jingqi <jingqi.liu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Naohiro Aota [Sun, 1 Dec 2019 01:49:56 +0000 (17:49 -0800)]
mm, swap: disallow swapon() on zoned block devices
A zoned block device consists of a number of zones. Zones are either
conventional and accepting random writes or sequential and requiring
that writes be issued in LBA order from each zone write pointer
position. For the write restriction, zoned block devices are not
suitable for a swap device. Disallow swapon on them.
[akpm@linux-foundation.org: reflow and reword comment, per Christoph]
Link: http://lkml.kernel.org/r/20191015085814.637837-1-naohiro.aota@wdc.com
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Theodore Y. Ts'o" <tytso@mit.edu>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Liu Xiang [Sun, 1 Dec 2019 01:49:53 +0000 (17:49 -0800)]
mm/gup.c: fix comments of __get_user_pages() and get_user_pages_remote()
Fix comments of __get_user_pages() and get_user_pages_remote(), make
them more clear.
Link: http://lkml.kernel.org/r/1572443533-3118-1-git-send-email-liuxiang_1999@126.com
Signed-off-by: Liu Xiang <liuxiang_1999@126.com>
Suggested-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
zhong jiang [Sun, 1 Dec 2019 01:49:50 +0000 (17:49 -0800)]
mm/gup.c: allow CMA migration to propagate errors back to caller
check_and_migrate_cma_pages() was recording the result of
__get_user_pages_locked() in an unsigned "nr_pages" variable.
Because __get_user_pages_locked() returns a signed value that can
include negative errno values, this had the effect of hiding errors.
Change check_and_migrate_cma_pages() implementation so that it uses a
signed variable instead, and propagates the results back to the caller
just as other gup internal functions do.
This was discovered with the help of unsigned_lesser_than_zero.cocci.
Link: http://lkml.kernel.org/r/1571671030-58029-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Suggested-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Konstantin Khlebnikov [Sun, 1 Dec 2019 01:49:47 +0000 (17:49 -0800)]
mm/filemap.c: warn if stale pagecache is left after direct write
generic_file_direct_write() tries to invalidate pagecache after O_DIRECT
write. Unlike to similar code in dio_complete() this silently ignores
error returned from invalidate_inode_pages2_range().
According to comment this code here because not all filesystems call
dio_complete() to do proper invalidation after O_DIRECT write. Noticeable
example is a blkdev_direct_IO().
This patch calls dio_warn_stale_pagecache() if invalidation fails.
Link: http://lkml.kernel.org/r/157270038294.4812.2238891109785106069.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Konstantin Khlebnikov [Sun, 1 Dec 2019 01:49:44 +0000 (17:49 -0800)]
fs/direct-io.c: keep dio_warn_stale_pagecache() when CONFIG_BLOCK=n
This helper prints warning if direct I/O write failed to invalidate cache,
and set EIO at inode to warn usersapce about possible data corruption.
See also commit
5a9d929d6e13 ("iomap: report collisions between directio
and buffered writes to userspace").
Direct I/O is supported by non-disk filesystems, for example NFS. Thus
generic code needs this even in kernel without CONFIG_BLOCK.
Link: http://lkml.kernel.org/r/157270038074.4812.7980855544557488880.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Konstantin Khlebnikov [Sun, 1 Dec 2019 01:49:41 +0000 (17:49 -0800)]
mm/filemap.c: remove redundant cache invalidation after async direct-io write
generic_file_direct_write() invalidates cache at entry. Second time this
should be done when request completes. But this function calls second
invalidation at exit unconditionally even for async requests.
This patch skips second invalidation for async requests (-EIOCBQUEUED).
Link: http://lkml.kernel.org/r/157270037850.4812.15036239021726025572.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yu Zhao [Sun, 1 Dec 2019 01:49:37 +0000 (17:49 -0800)]
mm/slub.c: clean up validate_slab()
The function doesn't need to return any value, and the check can be done
in one pass.
There is a behavior change: before the patch, we stop at the first invalid
free object; after the patch, we stop at the first invalid object, free or
in use. This shouldn't matter because the original behavior isn't
intended anyway.
Link: http://lkml.kernel.org/r/20191108193958.205102-1-yuzhao@google.com
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yu Zhao [Sun, 1 Dec 2019 01:49:34 +0000 (17:49 -0800)]
mm/slub.c: update comments
Slub doesn't use PG_active and PG_error anymore.
Link: http://lkml.kernel.org/r/20191007222023.162256-1-yuzhao@google.com
Signed-off-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miles Chen [Sun, 1 Dec 2019 01:49:31 +0000 (17:49 -0800)]
mm: slub: print the offset of fault addresses
With commit
ad67b74d2469 ("printk: hash addresses printed with %p"), it
is a little bit harder to match the fault addresses printed by
check_bytes_and_report() or slab_pad_check() in the dump because the
fault addresses may not show up in the dump.
Print the offset of the fault addresses to make it easier to match the
incorrect poison or padding values in the dump.
Before: We have to search the "63" in the dump. If we want to get the
offset of 63, we have to count it from the start of Object dump.
=============================================================
BUG kmalloc-128 (Not tainted): Poison overwritten
-------------------------------------------------------------
Disabling lock debugging due to kernel taint
INFO: 0x00000000570da294-0x00000000570da294.
First byte 0x63 instead of 0x6b
...
INFO: Object 0x000000006ebb3b9e @offset=14208 fp=0x0000000065862488
Redzone
00000000a6abccff: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
00000000741c16f0: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
0000000061ad278f: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
000000000467c1bd: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
000000008812766b: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
000000003d9b8f25: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
0000000000d80c33: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
00000000867b0d90: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Object
000000006ebb3b9e: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
000000005ea59a9f: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
000000003ef8bddc: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
000000008190375d: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
000000006df7fb32: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
0000000069474eae: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
0000000008073b7d: 6b 6b 6b 6b 63 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
00000000b45ae74d: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5
After: We know the fault address is at @offset=1508, and the Object is
at @offset=1408, so we know the fault address is at offset=100 within
the object.
=========================================================
BUG kmalloc-128 (Not tainted): Poison overwritten
---------------------------------------------------------
Disabling lock debugging due to kernel taint
INFO: 0x00000000638ec1d1-0x00000000638ec1d1 @offset=1508.
First byte 0x63 instead of 0x6b
...
INFO: Object 0x000000008171818d @offset=1408 fp=0x0000000066dae230
Redzone
00000000e2697ab6: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
0000000064b6a381: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
00000000e413a234: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
0000000004c1dfeb: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
000000009ad24d42: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
000000002a196a23: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
00000000a7b8468a: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Redzone
0000000088db6da3: bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
Object
000000008171818d: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
000000007c4035d4: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
000000004dd281a4: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
0000000079121dff: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
00000000756682a9: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
0000000053b7e541: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
0000000091f8d530: 6b 6b 6b 6b 63 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b
Object
000000009c76035c: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5
Link: http://lkml.kernel.org/r/20190925140807.20490-1-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pengfei Li [Sun, 1 Dec 2019 01:49:28 +0000 (17:49 -0800)]
mm, slab_common: use enum kmalloc_cache_type to iterate over kmalloc caches
The type of local variable *type* of new_kmalloc_cache() should be enum
kmalloc_cache_type instead of int, so correct it.
Link: http://lkml.kernel.org/r/1569241648-26908-4-git-send-email-lpf.vector@gmail.com
Signed-off-by: Pengfei Li <lpf.vector@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pengfei Li [Sun, 1 Dec 2019 01:49:25 +0000 (17:49 -0800)]
mm, slab: remove unused kmalloc_size()
The size of kmalloc can be obtained from kmalloc_info[], so remove
kmalloc_size() that will not be used anymore.
Link: http://lkml.kernel.org/r/1569241648-26908-3-git-send-email-lpf.vector@gmail.com
Signed-off-by: Pengfei Li <lpf.vector@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pengfei Li [Sun, 1 Dec 2019 01:49:21 +0000 (17:49 -0800)]
mm, slab: make kmalloc_info[] contain all types of names
Patch series "mm, slab: Make kmalloc_info[] contain all types of names", v6.
There are three types of kmalloc, KMALLOC_NORMAL, KMALLOC_RECLAIM
and KMALLOC_DMA.
The name of KMALLOC_NORMAL is contained in kmalloc_info[].name,
but the names of KMALLOC_RECLAIM and KMALLOC_DMA are dynamically
generated by kmalloc_cache_name().
Patch1 predefines the names of all types of kmalloc to save
the time spent dynamically generating names.
These changes make sense, and the time spent by new_kmalloc_cache()
has been reduced by approximately 36.3%.
Time spent by new_kmalloc_cache()
(CPU cycles)
5.3-rc7 66264
5.3-rc7+patch 42188
This patch (of 3):
There are three types of kmalloc, KMALLOC_NORMAL, KMALLOC_RECLAIM and
KMALLOC_DMA.
The name of KMALLOC_NORMAL is contained in kmalloc_info[].name, but the
names of KMALLOC_RECLAIM and KMALLOC_DMA are dynamically generated by
kmalloc_cache_name().
This patch predefines the names of all types of kmalloc to save the time
spent dynamically generating names.
Besides, remove the kmalloc_cache_name() that is no longer used.
Link: http://lkml.kernel.org/r/1569241648-26908-2-git-send-email-lpf.vector@gmail.com
Signed-off-by: Pengfei Li <lpf.vector@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ben Dooks [Sun, 1 Dec 2019 01:49:18 +0000 (17:49 -0800)]
fs/buffer.c: include internal.h for missing declarations
The declarations of __block_write_begin_int and guard_bio_eod are needed
from internal.h so include it to fix the following sparse warnings:
fs/buffer.c:1930:5: warning: symbol '__block_write_begin_int' was not declared. Should it be static?
fs/buffer.c:2994:6: warning: symbol 'guard_bio_eod' was not declared. Should it be static?
Link: http://lkml.kernel.org/r/20191011170039.16100-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Saurav Girepunje [Sun, 1 Dec 2019 01:49:15 +0000 (17:49 -0800)]
fs/buffer.c: fix use true/false for bool type
Use true/false for bool return type of has_bh_in_lru().
Link: http://lkml.kernel.org/r/20191029040529.GA7625@saurav
Signed-off-by: Saurav Girepunje <saurav.girepunje@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ding Xiang [Sun, 1 Dec 2019 01:49:12 +0000 (17:49 -0800)]
ocfs2: fix passing zero to 'PTR_ERR' warning
Fix a static code checker warning:
fs/ocfs2/acl.c:331
ocfs2_acl_chmod() warn: passing zero to 'PTR_ERR'
Link: http://lkml.kernel.org/r/1dee278b-6c96-eec2-ce76-fe6e07c6e20f@linux.alibaba.com
Fixes:
5ee0fbd50fd ("ocfs2: revert using ocfs2_acl_chmod to avoid inode cluster lock hang")
Signed-off-by: Ding Xiang <dingxiang@cmss.chinamobile.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Colin Ian King [Sun, 1 Dec 2019 01:49:08 +0000 (17:49 -0800)]
scripts/spelling.txt: add more spellings to spelling.txt
Here are some of the more common spelling mistakes and typos that I've
found while fixing up spelling mistakes in the kernel since July 2019.
Link: http://lkml.kernel.org/r/20191112092142.97989-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sat, 30 Nov 2019 19:34:33 +0000 (11:34 -0800)]
Merge tag 'fsnotify_for_v5.5-rc1' of git://git./linux/kernel/git/jack/linux-fs
Pull fsnotify updates from Jan Kara:
"Three fsnotify cleanups"
* tag 'fsnotify_for_v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
fsnotify: Add git tree reference to MAINTAINERS
fsnotify/fdinfo: exportfs_encode_inode_fh() takes pointer as 4th argument
fsnotify: move declaration of fsnotify_mark_connector_cachep to fsnotify.h
Linus Torvalds [Sat, 30 Nov 2019 19:16:07 +0000 (11:16 -0800)]
Merge tag 'for_v5.5-rc1' of git://git./linux/kernel/git/jack/linux-fs
Pull ext2, quota, reiserfs cleanups and fixes from Jan Kara:
- Refactor the quota on/off kernel internal interfaces (mostly for
ubifs quota support as ubifs does not want to have inodes holding
quota information)
- A few other small quota fixes and cleanups
- Various small ext2 fixes and cleanups
- Reiserfs xattr fix and one cleanup
* tag 'for_v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (28 commits)
ext2: code cleanup for descriptor_loc()
fs/quota: handle overflows of sysctl fs.quota.* and report as unsigned long
ext2: fix improper function comment
ext2: code cleanup for ext2_try_to_allocate()
ext2: skip unnecessary operations in ext2_try_to_allocate()
ext2: Simplify initialization in ext2_try_to_allocate()
ext2: code cleanup by calling ext2_group_last_block_no()
ext2: introduce new helper ext2_group_last_block_no()
reiserfs: replace open-coded atomic_dec_and_mutex_lock()
ext2: check err when partial != NULL
quota: Handle quotas without quota inodes in dquot_get_state()
quota: Make dquot_disable() work without quota inodes
quota: Drop dquot_enable()
fs: Use dquot_load_quota_inode() from filesystems
quota: Rename vfs_load_quota_inode() to dquot_load_quota_inode()
quota: Simplify dquot_resume()
quota: Factor out setup of quota inode
quota: Check that quota is not dirty before release
quota: fix livelock in dquot_writeback_dquots
ext2: don't set *count in the case of failure in ext2_try_to_allocate()
...
Linus Torvalds [Sat, 30 Nov 2019 19:13:33 +0000 (11:13 -0800)]
Merge tag 'erofs-for-5.5-rc1' of git://git./linux/kernel/git/xiang/erofs
Pull erofs updates from Gao Xiang:
"No major kernel updates for this round since I'm fully diving into
LZMA algorithm internals now to provide high CR XZ algorihm support.
That needs more work and time for me to get a better compression time.
Summary:
- Introduce superblock checksum support
- Set iowait when waiting I/O for sync decompression path
- Several code cleanups"
* tag 'erofs-for-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs:
erofs: remove unnecessary output in erofs_show_options()
erofs: drop all vle annotations for runtime names
erofs: support superblock checksum
erofs: set iowait for sync decompression
erofs: clean up decompress queue stuffs
erofs: get rid of __stagingpage_alloc helper
erofs: remove dead code since managed cache is now built-in
erofs: clean up collection handling routines
Linus Torvalds [Sat, 30 Nov 2019 19:10:39 +0000 (11:10 -0800)]
Merge tag '5.5-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs updates from Steve French:
"Various smb3 fixes (including 12 for stable) and also features
(addition of multichannel support)"
* tag '5.5-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: (41 commits)
CIFS: fix a white space issue in cifs_get_inode_info()
cifs: update internal module version number
cifs: Always update signing key of first channel
cifs: Fix retrieval of DFS referrals in cifs_mount()
cifs: Fix potential softlockups while refreshing DFS cache
cifs: Fix lookup of root ses in DFS referral cache
cifs: Fix use-after-free bug in cifs_reconnect()
cifs: dump channel info in DebugData
smb3: dump in_send and num_waiters stats counters by default
cifs: try harder to open new channels
CIFS: Properly process SMB3 lease breaks
cifs: move cifsFileInfo_put logic into a work-queue
cifs: try opening channels after mounting
CIFS: refactor cifs_get_inode_info()
cifs: switch servers depending on binding state
cifs: add server param
cifs: add multichannel mount options and data structs
cifs: sort interface list by speed
CIFS: Fix SMB2 oplock break processing
cifs: don't use 'pre:' for MODULE_SOFTDEP
...
Linus Torvalds [Sat, 30 Nov 2019 19:02:30 +0000 (11:02 -0800)]
Merge tag 'f2fs-for-5.5' of git://git./linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've introduced fairly small number of patches as below.
Enhancements:
- improve the in-place-update IO flow
- allocate segment to guarantee no GC for pinned files
Bug fixes:
- fix updatetime in lazytime mode
- potential memory leak in f2fs_listxattr
- record parent inode number in rename2 correctly
- fix deadlock in f2fs_gc along with atomic writes
- avoid needless data migration in GC"
* tag 'f2fs-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs:
f2fs: stop GC when the victim becomes fully valid
f2fs: expose main_blkaddr in sysfs
f2fs: choose hardlimit when softlimit is larger than hardlimit in f2fs_statfs_project()
f2fs: Fix deadlock in f2fs_gc() context during atomic files handling
f2fs: show f2fs instance in printk_ratelimited
f2fs: fix potential overflow
f2fs: fix to update dir's i_pino during cross_rename
f2fs: support aligned pinned file
f2fs: avoid kernel panic on corruption test
f2fs: fix wrong description in document
f2fs: cache global IPU bio
f2fs: fix to avoid memory leakage in f2fs_listxattr
f2fs: check total_segments from devices in raw_super
f2fs: update multi-dev metadata in resize_fs
f2fs: mark recovery flag correctly in read_raw_super_block()
f2fs: fix to update time in lazytime mode
Linus Torvalds [Sat, 30 Nov 2019 18:57:22 +0000 (10:57 -0800)]
Merge tag 'afs-next-
20191121' of git://git./linux/kernel/git/dhowells/linux-fs
Pull AFS updates from David Howells:
"Minor cleanups and fix:
- Minor fix to make some debugging statements display information
from the correct iov_iter.
- Rename some members and variables to make things more obvious or
consistent.
- Provide a helper to wrap increments of the usage count on the
afs_read struct.
- Use scnprintf() to print into a stack buffer rather than sprintf().
- Remove some set but unused variables"
* tag 'afs-next-
20191121' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Remove set but not used variable 'ret'
afs: Remove set but not used variables 'before', 'after'
afs: xattr: use scnprintf
afs: Introduce an afs_get_read() refcount helper
afs: Rename desc -> req in afs_fetch_data()
afs: Switch the naming of call->iter and call->_iter
afs: Use call->_iter not &call->iter in debugging statements
Linus Torvalds [Sat, 30 Nov 2019 18:53:02 +0000 (10:53 -0800)]
Merge tag 'ext4_for_linus' of git://git./linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"This merge window saw the the following new featuers added to ext4:
- Direct I/O via iomap (required the iomap-for-next branch from
Darrick as a prereq).
- Support for using dioread-nolock where the block size < page size.
- Support for encryption for file systems where the block size < page
size.
- Rework of journal credits handling so a revoke-heavy workload will
not cause the journal to run out of space.
- Replace bit-spinlocks with spinlocks in jbd2
Also included were some bug fixes and cleanups, mostly to clean up
corner cases from fuzzed file systems and error path handling"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (59 commits)
ext4: work around deleting a file with i_nlink == 0 safely
ext4: add more paranoia checking in ext4_expand_extra_isize handling
jbd2: make jbd2_handle_buffer_credits() handle reserved handles
ext4: fix a bug in ext4_wait_for_tail_page_commit
ext4: bio_alloc with __GFP_DIRECT_RECLAIM never fails
ext4: code cleanup for get_next_id
ext4: fix leak of quota reservations
ext4: remove unused variable warning in parse_options()
ext4: Enable encryption for subpage-sized blocks
fs/buffer.c: support fscrypt in block_read_full_page()
ext4: Add error handling for io_end_vec struct allocation
jbd2: Fine tune estimate of necessary descriptor blocks
jbd2: Provide trace event for handle restarts
ext4: Reserve revoke credits for freed blocks
jbd2: Make credit checking more strict
jbd2: Rename h_buffer_credits to h_total_credits
jbd2: Reserve space for revoke descriptor blocks
jbd2: Drop jbd2_space_needed()
jbd2: Account descriptor blocks into t_outstanding_credits
jbd2: Factor out common parts of stopping and restarting a handle
...
Linus Torvalds [Sat, 30 Nov 2019 18:48:24 +0000 (10:48 -0800)]
Merge tag 'vfs-5.5-merge-1' of git://git./fs/xfs/xfs-linux
Pull splice fix from Darrick Wong:
"Fix another place in the splice code where a pipe could ask a
filesystem for a longer read than the pipe actually has free buffer
space"
* tag 'vfs-5.5-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
splice: only read in as much information as there is pipe buffer space
Linus Torvalds [Sat, 30 Nov 2019 18:44:49 +0000 (10:44 -0800)]
Merge tag 'iomap-5.5-merge-11' of git://git./fs/xfs/xfs-linux
Pull iomap updates from Darrick Wong:
"In this release, we hoisted as much of XFS' writeback code into iomap
as was practicable, refactored the unshare file data function, added
the ability to perform buffered io copy on write, and tweaked various
parts of the directio implementation as needed to port ext4's directio
code (that will be a separate pull).
Summary:
- Make iomap_dio_rw callers explicitly tell us if they want us to
wait
- Port the xfs writeback code to iomap to complete the buffered io
library functions
- Refactor the unshare code to share common pieces
- Add support for performing copy on write with buffered writes
- Other minor fixes
- Fix unchecked return in iomap_bmap
- Fix a type casting bug in a ternary statement in
iomap_dio_bio_actor
- Improve tracepoints for easier diagnostic ability
- Fix pipe page leakage in directio reads"
* tag 'iomap-5.5-merge-11' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (31 commits)
iomap: Fix pipe page leakage during splicing
iomap: trace iomap_appply results
iomap: fix return value of iomap_dio_bio_actor on 32bit systems
iomap: iomap_bmap should check iomap_apply return value
iomap: Fix overflow in iomap_page_mkwrite
fs/iomap: remove redundant check in iomap_dio_rw()
iomap: use a srcmap for a read-modify-write I/O
iomap: renumber IOMAP_HOLE to 0
iomap: use write_begin to read pages to unshare
iomap: move the zeroing case out of iomap_read_page_sync
iomap: ignore non-shared or non-data blocks in xfs_file_dirty
iomap: always use AOP_FLAG_NOFS in iomap_write_begin
iomap: remove the unused iomap argument to __iomap_write_end
iomap: better document the IOMAP_F_* flags
iomap: enhance writeback error message
iomap: pass a struct page to iomap_finish_page_writeback
iomap: cleanup iomap_ioend_compare
iomap: move struct iomap_page out of iomap.h
iomap: warn on inline maps in iomap_writepage_map
iomap: lift the xfs writeback code to iomap
...