[PATCH v4 10/10] cacheinfo: Move resctrl's get_cache_id() to the cacheinfo header file

From: James Morse
Date: Tue May 26 2020 - 09:41:38 EST


resctrl/core.c defines get_cache_id() for use in its cpu-hotplug
callbacks. This gets the id attribute of the cache at the corresponding
level of a cpu.

Later rework means this private function needs to be shared. Move
it to the header file.

The name conflicts with a different definition in intel_cacheinfo.c,
name it get_cpu_cacheinfo_id() to show its relation with
get_cpu_cacheinfo().

Now this is visible on other architectures, check the id attribute
has actually been set.

Signed-off-by: James Morse <james.morse@xxxxxxx>
Reviewed-by: Babu Moger <babu.moger@xxxxxxx>
---
arch/x86/kernel/cpu/resctrl/core.c | 17 ++---------------
include/linux/cacheinfo.h | 21 +++++++++++++++++++++
2 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 587f9791d2a6..3cc0fe435d19 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -350,19 +350,6 @@ static void rdt_get_cdp_l2_config(void)
rdt_get_cdp_config(RDT_RESOURCE_L2, RDT_RESOURCE_L2CODE);
}

-static int get_cache_id(int cpu, int level)
-{
- struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu);
- int i;
-
- for (i = 0; i < ci->num_leaves; i++) {
- if (ci->info_list[i].level == level)
- return ci->info_list[i].id;
- }
-
- return -1;
-}
-
static void
mba_wrmsr_amd(struct rdt_domain *d, struct msr_param *m, struct rdt_resource *r)
{
@@ -560,7 +547,7 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_domain *d)
*/
static void domain_add_cpu(int cpu, struct rdt_resource *r)
{
- int id = get_cache_id(cpu, r->cache_level);
+ int id = get_cpu_cacheinfo_id(cpu, r->cache_level);
struct list_head *add_pos = NULL;
struct rdt_domain *d;

@@ -606,7 +593,7 @@ static void domain_add_cpu(int cpu, struct rdt_resource *r)

static void domain_remove_cpu(int cpu, struct rdt_resource *r)
{
- int id = get_cache_id(cpu, r->cache_level);
+ int id = get_cpu_cacheinfo_id(cpu, r->cache_level);
struct rdt_domain *d;

d = rdt_find_domain(r, id, NULL);
diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h
index 46b92cd61d0c..4f72b47973c3 100644
--- a/include/linux/cacheinfo.h
+++ b/include/linux/cacheinfo.h
@@ -3,6 +3,7 @@
#define _LINUX_CACHEINFO_H

#include <linux/bitops.h>
+#include <linux/cpu.h>
#include <linux/cpumask.h>
#include <linux/smp.h>

@@ -119,4 +120,24 @@ int acpi_find_last_cache_level(unsigned int cpu);

const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf);

+/*
+ * Get the id of the cache associated with @cpu at level @level.
+ * cpuhp lock must be held.
+ */
+static inline int get_cpu_cacheinfo_id(int cpu, int level)
+{
+ struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu);
+ int i;
+
+ for (i = 0; i < ci->num_leaves; i++) {
+ if (ci->info_list[i].level == level) {
+ if (ci->info_list[i].attributes & CACHE_ID)
+ return ci->info_list[i].id;
+ return -1;
+ }
+ }
+
+ return -1;
+}
+
#endif /* _LINUX_CACHEINFO_H */
--
2.19.1