Kan Liang a5398bffc0 perf/core: Flush PMU internal buffers for per-CPU events ... Sometimes the PMU internal buffers have to be flushed for per-CPU events during a context switch, e.g., large PEBS. Otherwise, the perf tool may report samples in locations that do not belong to the process where the samples are processed in, because PEBS does not tag samples with PID/TID. The current code only flush the buffers for a per-task event. It doesn't check a per-CPU event. Add a new event state flag, PERF_ATTACH_SCHED_CB, to indicate that the PMU internal buffers have to be flushed for this event during a context switch. Add sched_cb_entry and perf_sched_cb_usages back to track the PMU/cpuctx which is required to be flushed. Only need to invoke the sched_task() for per-CPU events in this patch. The per-task events have been handled in perf_event_context_sched_in/out already. Fixes: 9c964efa43 ("perf/x86/intel: Drain the PEBS buffer during context switches") Reported-by: Gabriel Marin <gmx@google.com> Originally-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lkml.kernel.org/r/20201130193842.10569-1-kan.liang@linux.intel.com		2021-03-06 12:52:39 +01:00
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callchain.c	uaccess: add force_uaccess_{begin,end} helpers	2020-08-12 10:57:59 -07:00
core.c	perf/core: Flush PMU internal buffers for per-CPU events	2021-03-06 12:52:39 +01:00
hw_breakpoint.c	powerpc/watchpoint: Don't allow concurrent perf and ptrace events	2020-05-19 00:14:45 +10:00
internal.h	perf: Optimize get_recursion_context()	2020-11-09 18:12:34 +01:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
ring_buffer.c	perf: Reduce stack usage of perf_output_begin()	2020-11-09 18:12:33 +01:00
uprobes.c	kernel: delete repeated words in comments	2021-02-26 09:41:03 -08:00