Skip to content
Commit 67063847 authored by Alexander Shishkin's avatar Alexander Shishkin Committed by Ingo Molnar
Browse files

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: default avatarAlexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: default avatarPeter 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: default avatarIngo Molnar <mingo@kernel.org>
parent 25e8920b
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment