Commit 10d235ac authored by James Morse's avatar James Morse Committed by Yang Yingliang
Browse files

drivers: base: cacheinfo: Add helper to search cacheinfo by of_node 



hulk inclusion
category: feature
bugzilla: 34278
CVE: NA

-------------------------------------------------

The MPAM ACPI table holds a PPTT-offset that describes a cache. Add a
helper cacheinfo_shared_cpu_map_search() to search the cacheinfo
structures for a cache that represents this firmware description.

The cacheinfo structures are freed and allocated over CPU online/offline,
the caller of this helper must hold the cpu-hotplug read lock while
the helper runs, and while it holds the return value.

Signed-off-by: default avatarJames Morse <james.morse@arm.com>
Link: http://www.linux-arm.org/git?p=linux-jm.git;a=patch;h=9e5b7ec7c145019f7160c56795ede536f0de5347


Signed-off-by: default avatarWang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: default avatarXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: default avatarCheng Jian <cj.chengjian@huawei.com>
Signed-off-by: default avatarYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: default avatarCheng Jian <cj.chengjian@huawei.com>
parent b55756d8

drivers/base/cacheinfo.c

+38 −0
Original line number Diff line number Diff line
@@ -213,6 +213,44 @@ int __weak cache_setup_acpi(unsigned int cpu) 
	return -ENOTSUPP;

}



/**

 * cacheinfo_shared_cpu_map_search() - find an instance of struct cacheinfo

 * from the provided firmware description.

 * Caller must hold cpus_read_lock() until its finished with the cacheinfo.

 *

 * Return a CPUs cache leaf described @fw_desc, or NULL.

 */

struct cacheinfo *cacheinfo_shared_cpu_map_search(void *fw_token)

{

	struct cacheinfo *iter;

	unsigned int cpu, index;

	struct cpu_cacheinfo *cpu_ci;



	for_each_online_cpu(cpu) {

		cpu_ci = get_cpu_cacheinfo(cpu);



		/*

		 * info_list of this cacheinfo instance

		 * may not be initialized because sometimes

		 * free_cache_attributes() may free this

		 * info_list but not set num_leaves to zero,

		 * for example when PPTT is not supported.

		 */

		if (!cpu_ci->info_list)

		    continue;



		for (index = 0; index < cache_leaves(cpu); index++) {

			iter = cpu_ci->info_list + index;



			if (iter->fw_token == fw_token) {

				return iter;

			}

		}

	}



	return NULL;

}



unsigned int coherency_max_size;



static int cache_shared_cpu_map_setup(unsigned int cpu)

include/linux/cacheinfo.h

+1 −0
Original line number Diff line number Diff line
@@ -97,6 +97,7 @@ int func(unsigned int cpu) \ 
}



struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);

struct cacheinfo *cacheinfo_shared_cpu_map_search(void *fw_desc);

int init_cache_level(unsigned int cpu);

int populate_cache_leaves(unsigned int cpu);

int cache_setup_acpi(unsigned int cpu);