perf/x86/uncore: Fix event group support
[ Upstream commit 75be6f70 ] The events in the same group don't start or stop simultaneously. Here is the ftrace when enabling event group for uncore_iio_0: # perf stat -e "{uncore_iio_0/event=0x1/,uncore_iio_0/event=0xe/}" <idle>-0 [000] d.h. 8959.064832: read_msr: a41, value b2b0b030 //Read counter reg of IIO unit0 counter0 <idle>-0 [000] d.h. 8959.064835: write_msr: a48, value 400001 //Write Ctrl reg of IIO unit0 counter0 to enable counter0. <------ Although counter0 is enabled, Unit Ctrl is still freezed. Nothing will count. We are still good here. <idle>-0 [000] d.h. 8959.064836: read_msr: a40, value 30100 //Read Unit Ctrl reg of IIO unit0 <idle>-0 [000] d.h. 8959.064838: write_msr: a40, value 30000 //Write Unit Ctrl reg of IIO unit0 to enable all counters in the unit by clear Freeze bit <------Unit0 is un-freezed. Counter0 has been enabled. Now it starts counting. But counter1 has not been enabled yet. The issue starts here. <idle>-0 [000] d.h. 8959.064846: read_msr: a42, value 0 //Read counter reg of IIO unit0 counter1 <idle>-0 [000] d.h. 8959.064847: write_msr: a49, value 40000e //Write Ctrl reg of IIO unit0 counter1 to enable counter1. <------ Now, counter1 just starts to count. Counter0 has been running for a while. Current code un-freezes the Unit Ctrl right after the first counter is enabled. The subsequent group events always loses some counter values. Implement pmu_enable and pmu_disable support for uncore, which can help to batch hardware accesses. No one uses uncore_enable_box and uncore_disable_box. Remove them. Signed-off-by: Kan Liang <kan.liang@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> 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> Cc: linux-drivers-review@eclists.intel.com Cc: linux-perf@eclists.intel.com Fixes: 087bfbb0 ("perf/x86: Add generic Intel uncore PMU support") Link: https://lkml.kernel.org/r/1572014593-31591-1-git-send-email-kan.liang@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
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