pNFS/flexfiles: Fix layoutstat periodic reporting

Putting the periodicity timer in the mirror instances is causing
non-scalable reporting behaviour and missed reporting intervals.
When you recall layouts and/or implement client side mirroring, it
leads to consecutive reports with only a few ms between RPC calls.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fixes: d0379a5d066a9 ("pNFS/flexfiles: Support server-supplied...")

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index e6206ea..ee1c94c 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -37,6 +37,7 @@ ff_layout_alloc_layout_hdr(struct inode *inode, gfp_t gfp_flags)
        if (ffl) {
                INIT_LIST_HEAD(&ffl->error_list);
                INIT_LIST_HEAD(&ffl->mirrors);
+               ffl->last_report_time = ktime_get();
                return &ffl->generic_hdr;
        } else
                return NULL;
@@ -640,19 +641,18 @@ nfs4_ff_layoutstat_start_io(struct nfs4_ff_layout_mirror *mirror,
 {
        static const ktime_t notime = {0};
        s64 report_interval = FF_LAYOUTSTATS_REPORT_INTERVAL;
+       struct nfs4_flexfile_layout *ffl = FF_LAYOUT_FROM_HDR(mirror->layout);
 
        nfs4_ff_start_busy_timer(&layoutstat->busy_timer, now);
        if (ktime_equal(mirror->start_time, notime))
                mirror->start_time = now;
-       if (ktime_equal(mirror->last_report_time, notime))
-               mirror->last_report_time = now;
        if (mirror->report_interval != 0)
                report_interval = (s64)mirror->report_interval * 1000LL;
        else if (layoutstats_timer != 0)
                report_interval = (s64)layoutstats_timer * 1000LL;
-       if (ktime_to_ms(ktime_sub(now, mirror->last_report_time)) >=
+       if (ktime_to_ms(ktime_sub(now, ffl->last_report_time)) >=
                        report_interval) {
-               mirror->last_report_time = now;
+               ffl->last_report_time = now;
                return true;
        }
 

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.h b/fs/nfs/flexfilelayout/flexfilelayout.h
index 1bcdb15..3ee0c9f 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayout.h
+++ b/fs/nfs/flexfilelayout/flexfilelayout.h
@@ -84,7 +84,6 @@ struct nfs4_ff_layout_mirror {
        struct nfs4_ff_layoutstat       read_stat;
        struct nfs4_ff_layoutstat       write_stat;
        ktime_t                         start_time;
-       ktime_t                         last_report_time;
        u32                             report_interval;
 };
 
@@ -101,6 +100,7 @@ struct nfs4_flexfile_layout {
        struct pnfs_ds_commit_info commit_info;
        struct list_head        mirrors;
        struct list_head        error_list; /* nfs4_ff_layout_ds_err */
+       ktime_t                 last_report_time; /* Layoutstat report times */
 };
 
 static inline struct nfs4_flexfile_layout *