diff options
| author | Alexandre Ghiti <alexghiti@rivosinc.com> | 2024-08-26 18:52:10 +0200 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-09-10 20:28:02 -0700 |
| commit | 2840dadf0dde92638d13b97998026c5fcddbdceb (patch) | |
| tree | 7e44d4f3b862be492c3841ff83b93d4d03f62219 /drivers/perf/riscv_pmu_sbi.c | |
| parent | 1ff95eb2bebda50c4c5406caaf201e0fcb24cc8f (diff) | |
drivers: perf: Fix smp_processor_id() use in preemptible code
As reported in [1], the use of smp_processor_id() in
pmu_sbi_device_probe() must be protected by disabling the preemption, so
simple use get_cpu()/put_cpu() instead.
Reported-by: Nam Cao <namcao@linutronix.de>
Closes: https://lore.kernel.org/linux-riscv/20240820074925.ReMKUPP3@linutronix.de/ [1]
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Tested-by: Nam Cao <namcao@linutronix.de>
Fixes: a8625217a054 ("drivers/perf: riscv: Implement SBI PMU snapshot function")
Reported-by: Andrea Parri <parri.andrea@gmail.com>
Tested-by: Andrea Parri <parri.andrea@gmail.com>
Link: https://lore.kernel.org/r/20240826165210.124696-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'drivers/perf/riscv_pmu_sbi.c')
| -rw-r--r-- | drivers/perf/riscv_pmu_sbi.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c index 31a17a56eb3b..25b1b699b3e2 100644 --- a/drivers/perf/riscv_pmu_sbi.c +++ b/drivers/perf/riscv_pmu_sbi.c @@ -1373,11 +1373,15 @@ static int pmu_sbi_device_probe(struct platform_device *pdev) /* SBI PMU Snapsphot is only available in SBI v2.0 */ if (sbi_v2_available) { + int cpu; + ret = pmu_sbi_snapshot_alloc(pmu); if (ret) goto out_unregister; - ret = pmu_sbi_snapshot_setup(pmu, smp_processor_id()); + cpu = get_cpu(); + + ret = pmu_sbi_snapshot_setup(pmu, cpu); if (ret) { /* Snapshot is an optional feature. Continue if not available */ pmu_sbi_snapshot_free(pmu); @@ -1391,6 +1395,7 @@ static int pmu_sbi_device_probe(struct platform_device *pdev) */ static_branch_enable(&sbi_pmu_snapshot_available); } + put_cpu(); } register_sysctl("kernel", sbi_pmu_sysctl_table); |