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linux/arch/x86/events
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Luo Gengkun 8d37031464 perf/x86: Fix non-sampling (counting) events on certain x86 platforms 
[ Upstream commit 1a97fea9db ]

Perf doesn't work at perf stat for hardware events on certain x86 platforms:

 $perf stat -- sleep 1
 Performance counter stats for 'sleep 1':
             16.44 msec task-clock                       #    0.016 CPUs utilized
                 2      context-switches                 #  121.691 /sec
                 0      cpu-migrations                   #    0.000 /sec
                54      page-faults                      #    3.286 K/sec
   <not supported>	cycles
   <not supported>	instructions
   <not supported>	branches
   <not supported>	branch-misses

The reason is that the check in x86_pmu_hw_config() for sampling events is
unexpectedly applied to counting events as well.

It should only impact x86 platforms with limit_period used for non-PEBS
events. For Intel platforms, it should only impact some older platforms,
e.g., HSW, BDW and NHM.

Fixes: 88ec7eedbb ("perf/x86: Fix low freqency setting issue")
Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Link: https://lore.kernel.org/r/20250423064724.3716211-1-luogengkun@huaweicloud.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2025-05-02 07:59:04 +02:00
..
amd perf/core: Save raw sample data conditionally based on sample type 2025-02-08 09:56:53 +01:00
intel perf/x86/intel/uncore: Fix the scale of IIO free running counters on SPR 2025-04-25 10:47:57 +02:00
zhaoxin perf/x86: Support counter mask 2024-07-04 16:00:36 +02:00
core.c perf/x86: Fix non-sampling (counting) events on certain x86 platforms 2025-05-02 07:59:04 +02:00
Kconfig perf/x86/Kconfig: Fix indentation in the Kconfig file 2022-05-25 15:54:26 +02:00
Makefile perf/x86: Move branch classifier 2022-08-27 00:05:44 +02:00
msr.c perf/x86/msr: Switch to new Intel CPU model defines 2024-04-29 10:31:04 +02:00
perf_event.h perf/x86/intel: Avoid disable PMU if !cpuc->enabled in sample read 2025-04-10 14:39:37 +02:00
perf_event_flags.h perf/x86/intel: Support branch counters logging 2023-10-27 15:05:11 +02:00
probe.c perf/x86/rapl: Add msr mask support 2021-02-10 14:44:54 +01:00
probe.h perf/x86/rapl: Add msr mask support 2021-02-10 14:44:54 +01:00
rapl.c perf/x86/rapl: Add support for Intel Arrow Lake U 2025-03-22 12:54:21 -07:00
utils.c perf/x86/lbr: Filter vsyscall addresses 2023-10-08 12:25:18 +02:00