github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-26 16:12:59 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

perf/arm_dsu: Avoid placing cpumask on the stack

Browse Source 
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>
This commit is contained in:
Dawei Li 2024-04-03 23:59:45 +08:00 committed by Will Deacon
parent b5310fa1fe
commit bea2a13b20
1 changed files with 6 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
drivers/perf/arm_dsu_pmu.c
View File

@ -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;