diff options
| author | Kan Liang <[email protected]> | 2025-04-24 13:47:18 +0000 |
|---|---|---|
| committer | Peter Zijlstra <[email protected]> | 2025-04-25 12:55:19 +0000 |
| commit | 7da9960b59fb7e590eb8538c9428db55a4ea2d23 (patch) | |
| tree | 1a72230ecd4aebbd55185837d9e2e6ffba9512bb /drivers/gpu/drm/amd/amdgpu/amdgpu_atomfirmware.c | |
| parent | perf/x86/intel: Check the X86 leader for pebs_counter_event_group (diff) | |
| download | kernel-7da9960b59fb7e590eb8538c9428db55a4ea2d23.tar.gz kernel-7da9960b59fb7e590eb8538c9428db55a4ea2d23.zip | |
perf/x86/intel/ds: Fix counter backwards of non-precise events counters-snapshotting
The counter backwards may be observed in the PMI handler when
counters-snapshotting some non-precise events in the freq mode.
For the non-precise events, it's possible the counters-snapshotting
records a positive value for an overflowed PEBS event. Then the HW
auto-reload mechanism reset the counter to 0 immediately. Because the
pebs_event_reset is cleared in the freq mode, which doesn't set the
PERF_X86_EVENT_AUTO_RELOAD.
In the PMI handler, 0 will be read rather than the positive value
recorded in the counters-snapshotting record.
The counters-snapshotting case has to be specially handled. Since the
event value has been updated when processing the counters-snapshotting
record, only needs to set the new period for the counter via
x86_pmu_set_period().
Fixes: e02e9b0374c3 ("perf/x86/intel: Support PEBS counters snapshotting")
Signed-off-by: Kan Liang <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_atomfirmware.c')
0 files changed, 0 insertions, 0 deletions