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perf/x86/intel/pt: Opportunistically use single range output mode
authorAlexander Shishkin <alexander.shishkin@linux.intel.com>
Tue, 5 Nov 2019 08:27:00 +0000 (10:27 +0200)
committerIngo Molnar <mingo@kernel.org>
Wed, 13 Nov 2019 10:06:17 +0000 (11:06 +0100)
commit670638477aede0d7a355ced04b569214aa3feacd
tree6b182fa1d1bf57e6a150965c0057e4c0fe79d600
parent25e8920b301c133aeaa9f57d81295bf4ac78e17b
perf/x86/intel/pt: Opportunistically use single range output mode

Most of PT implementations support Single Range Output mode, which is
an alternative to ToPA that can be used for a single contiguous buffer
and if we don't require an interrupt, that is, in AUX snapshot mode.

Now that perf core will use high order allocations for the AUX buffer,
in many cases the first condition will also be satisfied.

The two most obvious benefits of the Single Range Output mode over the
ToPA are:

 * not having to allocate the ToPA table(s),
 * not using the ToPA walk hardware.

Make use of this functionality where available and appropriate.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191105082701.78442-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/events/intel/pt.c
arch/x86/events/intel/pt.h