Adrian Hunter 53385a400a perf intel-pt: Fix PEBS-via-PT data_src
[ Upstream commit e00eac6b5b6d956f38d8880c44bf7fd9954063c3 ]

The Fixes commit did not add support for decoding PEBS-via-PT data_src.
Fix by adding support.

PEBS-via-PT is a feature of some E-core processors, starting with
processors based on Tremont microarchitecture. Because the kernel only
supports Intel PT features that are on all processors, there is no support
for PEBS-via-PT on hybrids.

Currently that leaves processors based on Tremont, Gracemont and Crestmont,
however there are no events on Tremont that produce data_src information,
and for Gracemont and Crestmont there are only:

	mem-loads	event=0xd0,umask=0x5,ldlat=3
	mem-stores	event=0xd0,umask=0x6

Affected processors include Alder Lake N (Gracemont), Sierra Forest
(Crestmont) and Grand Ridge (Crestmont).

Example:

 # perf record -d -e intel_pt/branch=0/ -e mem-loads/aux-output/pp uname

 Before:

  # perf.before script --itrace=o -Fdata_src
            0 |OP No|LVL N/A|SNP N/A|TLB N/A|LCK No|BLK  N/A
            0 |OP No|LVL N/A|SNP N/A|TLB N/A|LCK No|BLK  N/A

 After:

  # perf script --itrace=o -Fdata_src
  10268100142 |OP LOAD|LVL L1 hit|SNP None|TLB L1 or L2 hit|LCK No|BLK  N/A
  10450100442 |OP LOAD|LVL L2 hit|SNP None|TLB L2 miss|LCK No|BLK  N/A

Fixes: 975846eddf ("perf intel-pt: Add memory information to synthesized PEBS sample")
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20250512093932.79854-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-06-19 15:28:27 +02:00
2025-06-19 15:28:25 +02:00
2022-09-28 09:02:20 +02:00
2025-06-04 14:42:26 +02:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Description
No description provided
Readme 7.9 GiB
Languages
C 97.7%
Assembly 1.6%
Makefile 0.3%
Perl 0.1%