drivers/perf: riscv: Reset the counter to hpmevent mapping while starting cpus

Currently, we stop all the counters while a new cpu is brought online.
However, the hpmevent to counter mappings are not reset. The firmware may
have some stale encoding in their mapping structure which may lead to
undesirable results. We have not encountered such scenario though.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20240628-misc_perf_fixes-v4-2-e01cfddcf035@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index a2e4005e1fd01c4e6f3a10228352461d9e653932..94bc369a345465a25cc59f5c92f748950671b2f7 100644 (file)
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -762,7 +762,7 @@ static inline void pmu_sbi_stop_all(struct riscv_pmu *pmu)
         * which may include counters that are not enabled yet.
         */
        sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP,
-                 0, pmu->cmask, 0, 0, 0, 0);
+                 0, pmu->cmask, SBI_PMU_STOP_FLAG_RESET, 0, 0, 0);
 }
 
 static inline void pmu_sbi_stop_hw_ctrs(struct riscv_pmu *pmu)