[PATCH v4 4/4] x86/resctrl: Replace open code cacheinfo searches

From: Tony Luck
Date: Sun Jun 09 2024 - 20:40:13 EST


pseudo_lock_region_init() and rdtgroup_cbm_to_size() open code
a search for details of a particular cache level.

Replace with get_cpu_cacheinfo_level()

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 17 ++++++-----------
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 14 +++++---------
2 files changed, 11 insertions(+), 20 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index aacf236dfe3b..1bbfd3c1e300 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -292,9 +292,8 @@ static void pseudo_lock_region_clear(struct pseudo_lock_region *plr)
*/
static int pseudo_lock_region_init(struct pseudo_lock_region *plr)
{
- struct cpu_cacheinfo *ci;
+ struct cacheinfo *ci;
int ret;
- int i;

/* Pick the first cpu we find that is associated with the cache. */
plr->cpu = cpumask_first(&plr->d->cpu_mask);
@@ -306,15 +305,11 @@ static int pseudo_lock_region_init(struct pseudo_lock_region *plr)
goto out_region;
}

- ci = get_cpu_cacheinfo(plr->cpu);
-
- plr->size = rdtgroup_cbm_to_size(plr->s->res, plr->d, plr->cbm);
-
- for (i = 0; i < ci->num_leaves; i++) {
- if (ci->info_list[i].level == plr->s->res->cache_level) {
- plr->line_size = ci->info_list[i].coherency_line_size;
- return 0;
- }
+ ci = get_cpu_cacheinfo_level(plr->cpu, plr->s->res->cache_level);
+ if (ci) {
+ plr->line_size = ci->coherency_line_size;
+ plr->size = rdtgroup_cbm_to_size(plr->s->res, plr->d, plr->cbm);
+ return 0;
}

ret = -1;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 02f213f1c51c..cb68a121dabb 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1450,18 +1450,14 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of,
unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
struct rdt_domain *d, unsigned long cbm)
{
- struct cpu_cacheinfo *ci;
unsigned int size = 0;
- int num_b, i;
+ struct cacheinfo *ci;
+ int num_b;

num_b = bitmap_weight(&cbm, r->cache.cbm_len);
- ci = get_cpu_cacheinfo(cpumask_any(&d->cpu_mask));
- for (i = 0; i < ci->num_leaves; i++) {
- if (ci->info_list[i].level == r->cache_level) {
- size = ci->info_list[i].size / r->cache.cbm_len * num_b;
- break;
- }
- }
+ ci = get_cpu_cacheinfo_level(cpumask_any(&d->cpu_mask), r->cache_level);
+ if (ci)
+ size = ci->size / r->cache.cbm_len * num_b;

return size;
}
--
2.45.0