From 685cb1674060c2cb1b9da051a12933c082b8e874 Mon Sep 17 00:00:00 2001 From: Tony Luck Date: Sun, 9 Jun 2024 17:39:26 -0700 Subject: [PATCH] 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 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 Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Reinette Chatre Link: https://lore.kernel.org/r/20240610003927.341707-4-tony.luck@intel.com --- include/linux/cacheinfo.h | 37 ++++++++++++++++++++++++++----------- 1 file changed, 26 insertions(+), 11 deletions(-) diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h index 2cb15fe4fe12..3dde175f4108 100644 --- a/include/linux/cacheinfo.h +++ b/include/linux/cacheinfo.h @@ -3,6 +3,7 @@ #define _LINUX_CACHEINFO_H #include +#include #include #include @@ -112,24 +113,38 @@ int acpi_get_cache_info(unsigned int cpu, const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf); +/* + * Get the cacheinfo structure for the cache associated with @cpu at + * level @level. + * cpuhp lock must be held. + */ +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]; + return NULL; + } + } + + 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 cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu); - int i; + struct cacheinfo *ci = get_cpu_cacheinfo_level(cpu, level); - 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; + return ci ? ci->id : -1; } #ifdef CONFIG_ARM64