From 133a6d1fe7d7ad8393af025c4dde379c0616661f Mon Sep 17 00:00:00 2001 From: Atish Patra Date: Mon, 11 Jul 2022 10:46:29 -0700 Subject: [PATCH] RISC-V: Update user page mapping only once during start Currently, riscv_pmu_event_set_period updates the userpage mapping. However, the caller of riscv_pmu_event_set_period should update the userpage mapping because the counter can not be updated/started from set_period function in counter overflow path. Invoke the perf_event_update_userpage at the caller so that it doesn't get invoked twice during counter start path. Fixes: f5bfa23f576f ("RISC-V: Add a perf core library for pmu drivers") Reviewed-by: Anup Patel Signed-off-by: Atish Patra Reviewed-by: Guo Ren Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20220711174632.4186047-3-atishp@rivosinc.com Signed-off-by: Palmer Dabbelt --- drivers/perf/riscv_pmu.c | 1 - drivers/perf/riscv_pmu_sbi.c | 1 + 2 files changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/perf/riscv_pmu.c b/drivers/perf/riscv_pmu.c index b2b8d207..130b9f1 100644 --- a/drivers/perf/riscv_pmu.c +++ b/drivers/perf/riscv_pmu.c @@ -170,7 +170,6 @@ int riscv_pmu_event_set_period(struct perf_event *event) left = (max_period >> 1); local64_set(&hwc->prev_count, (u64)-left); - perf_event_update_userpage(event); return overflow; } diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c index 0cb694b..3735337 100644 --- a/drivers/perf/riscv_pmu_sbi.c +++ b/drivers/perf/riscv_pmu_sbi.c @@ -532,6 +532,7 @@ static inline void pmu_sbi_start_overflow_mask(struct riscv_pmu *pmu, sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1, flag, init_val, 0, 0); #endif + perf_event_update_userpage(event); } ctr_ovf_mask = ctr_ovf_mask >> 1; idx++; -- 2.7.4