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| author | Dawei Li <dawei.li@shingroup.cn> | 2024-04-03 23:59:45 +0800 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2024-04-09 16:47:15 +0100 |
| commit | bea2a13b207ef48732daf329564101a07df14e3a (patch) | |
| tree | 3c31e25f3f26b451332d10aadd7ad97df7549efb /drivers/perf | |
| parent | b5310fa1fe8e29e82dd88ef23e2f04ac533548e1 (diff) | |
| download | linux-bea2a13b207ef48732daf329564101a07df14e3a.tar.gz linux-bea2a13b207ef48732daf329564101a07df14e3a.tar.bz2 linux-bea2a13b207ef48732daf329564101a07df14e3a.zip | |
perf/arm_dsu: Avoid placing cpumask on the stack
In general it's preferable to avoid placing cpumasks on the stack, as
for large values of NR_CPUS these can consume significant amounts of
stack space and make stack overflows more likely.
Use cpumask_any_and_but() to avoid the need for a temporary cpumask on
the stack.
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Dawei Li <dawei.li@shingroup.cn>
Link: https://lore.kernel.org/r/20240403155950.2068109-6-dawei.li@shingroup.cn
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'drivers/perf')
| -rw-r--r-- | drivers/perf/arm_dsu_pmu.c | 19 |
1 files changed, 6 insertions, 13 deletions
diff --git a/drivers/perf/arm_dsu_pmu.c b/drivers/perf/arm_dsu_pmu.c index bae3ca37f846..adc0bbb5fafe 100644 --- a/drivers/perf/arm_dsu_pmu.c +++ b/drivers/perf/arm_dsu_pmu.c @@ -230,15 +230,6 @@ static const struct attribute_group *dsu_pmu_attr_groups[] = { NULL, }; -static int dsu_pmu_get_online_cpu_any_but(struct dsu_pmu *dsu_pmu, int cpu) -{ - struct cpumask online_supported; - - cpumask_and(&online_supported, - &dsu_pmu->associated_cpus, cpu_online_mask); - return cpumask_any_but(&online_supported, cpu); -} - static inline bool dsu_pmu_counter_valid(struct dsu_pmu *dsu_pmu, u32 idx) { return (idx < dsu_pmu->num_counters) || @@ -827,14 +818,16 @@ static int dsu_pmu_cpu_online(unsigned int cpu, struct hlist_node *node) static int dsu_pmu_cpu_teardown(unsigned int cpu, struct hlist_node *node) { - int dst; - struct dsu_pmu *dsu_pmu = hlist_entry_safe(node, struct dsu_pmu, - cpuhp_node); + struct dsu_pmu *dsu_pmu; + unsigned int dst; + + dsu_pmu = hlist_entry_safe(node, struct dsu_pmu, cpuhp_node); if (!cpumask_test_and_clear_cpu(cpu, &dsu_pmu->active_cpu)) return 0; - dst = dsu_pmu_get_online_cpu_any_but(dsu_pmu, cpu); + dst = cpumask_any_and_but(&dsu_pmu->associated_cpus, + cpu_online_mask, cpu); /* If there are no active CPUs in the DSU, leave IRQ disabled */ if (dst >= nr_cpu_ids) return 0; |