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perf: riscv: Fix selecting counters in legacy mode

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It is required to check event type before checking event config.
Events with the different types can have the same config.
This check is missed for legacy mode code

For such perf usage:
    sysctl -w kernel.perf_user_access=2
    perf stat -e cycles,L1-dcache-loads --
driver will try to force both events to CYCLE counter.

This commit implements event type check before forcing
events on the special counters.

Signed-off-by: Shifrin Dmitry <dmitry.shifrin@syntacore.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Fixes: cc4c07c89a ("drivers: perf: Implement perf event mmap support in the SBI backend")
Link: https://lore.kernel.org/r/20240729125858.630653-1-dmitry.shifrin@syntacore.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Shifrin Dmitry 2024-07-29 15:58:58 +03:00 committed by Palmer Dabbelt
parent 57e5c814e9
commit 941a8e9b7a
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1 changed files with 1 additions and 1 deletions
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drivers/perf/riscv_pmu_sbi.c
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@ -416,7 +416,7 @@ static int pmu_sbi_ctr_get_idx(struct perf_event *event)
* but not in the user access mode as we want to use the other counters * but not in the user access mode as we want to use the other counters
* that support sampling/filtering. * that support sampling/filtering.
*/ */
if (hwc->flags & PERF_EVENT_FLAG_LEGACY) { if ((hwc->flags & PERF_EVENT_FLAG_LEGACY) && (event->attr.type == PERF_TYPE_HARDWARE)) {
if (event->attr.config == PERF_COUNT_HW_CPU_CYCLES) { if (event->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
cflags |= SBI_PMU_CFG_FLAG_SKIP_MATCH; cflags |= SBI_PMU_CFG_FLAG_SKIP_MATCH;
cmask = 1; cmask = 1;