The following commit has been merged into the x86/cache branch of tip:
Commit-ID: 685cb1674060c2cb1b9da051a12933c082b8e874
Gitweb: https://git.kernel.org/tip/685cb1674060c2cb1b9da051a12933c082b8e874
Author: Tony Luck <tony.luck@xxxxxxxxx>
AuthorDate: Sun, 09 Jun 2024 17:39:26 -07:00
Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx>
CommitterDate: Mon, 10 Jun 2024 08:50:09 +02:00
cacheinfo: Add function to get cacheinfo for a given CPU and cache level
Resctrl open codes a search for information about a given cache level in
a couple of places (and more are on the way).
Provide a new inline function get_cpu_cacheinfo_level() in
<linux/cacheinfo.h> to do the search and return a pointer to the
cacheinfo structure.
Add lockdep_assert_cpus_held() to enforce the comment that cpuhp lock
must be held.
Simplify the existing get_cpu_cacheinfo_id() by using this new function
to do the search.
Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Link: https://lore.kernel.org/r/20240610003927.341707-4-tony.luck@xxxxxxxxx
---
include/linux/cacheinfo.h | 25 ++++++++++++++++++++-----
1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h
index 2cb15fe..3dde175 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/cpuhplock.h>
#include <linux/cpumask.h>
#include <linux/smp.h>
@@ -113,23 +114,37 @@ int acpi_get_cache_info(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.
+ * Get the cacheinfo structure for the cache associated with @cpu at
+ * level @level.
* cpuhp lock must be held.
*/
-static inline int get_cpu_cacheinfo_id(int cpu, int level)
+static inline struct cacheinfo *get_cpu_cacheinfo_level(int cpu, int level)
{
struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu);
int i;
+ lockdep_assert_cpus_held();
+
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 &ci->info_list[i];
+ return NULL;
}
}
- return -1;
+ return NULL;
+}
+
+/*
+ * 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 cacheinfo *ci = get_cpu_cacheinfo_level(cpu, level);
+
+ return ci ? ci->id : -1;
}
#ifdef CONFIG_ARM64
|