Add a stat counter of culling events whereby the cache backend culls a file to make space (when asked by cachefilesd in this case) and display in /proc/fs/fscache/stats. Signed-off-by: David Howells <dhowells@xxxxxxxxxx> cc: linux-cachefs@xxxxxxxxxx Link: https://lore.kernel.org/r/163819654165.215744.3797804661644212436.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v1 Link: https://lore.kernel.org/r/163906961387.143852.9291157239960289090.stgit@xxxxxxxxxxxxxxxxxxxxxx/ # v2 --- fs/cachefiles/namei.c | 1 + fs/fscache/stats.c | 7 +++++-- include/linux/fscache-cache.h | 3 +++ 3 files changed, 9 insertions(+), 2 deletions(-) diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index ab3ca598acac..9bd692870617 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -805,6 +805,7 @@ int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir, if (ret < 0) goto error; + fscache_count_culled(); dput(victim); _leave(" = 0"); return 0; diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c index db2f4e225dd9..fc94e5e79f1c 100644 --- a/fs/fscache/stats.c +++ b/fs/fscache/stats.c @@ -46,6 +46,8 @@ atomic_t fscache_n_no_write_space; EXPORT_SYMBOL(fscache_n_no_write_space); atomic_t fscache_n_no_create_space; EXPORT_SYMBOL(fscache_n_no_create_space); +atomic_t fscache_n_culled; +EXPORT_SYMBOL(fscache_n_culled); /* * display the general statistics @@ -86,9 +88,10 @@ int fscache_stats_show(struct seq_file *m, void *v) atomic_read(&fscache_n_relinquishes_retire), atomic_read(&fscache_n_relinquishes_dropped)); - seq_printf(m, "NoSpace: nwr=%u ncr=%u\n", + seq_printf(m, "NoSpace: nwr=%u ncr=%u cull=%u\n", atomic_read(&fscache_n_no_write_space), - atomic_read(&fscache_n_no_create_space)); + atomic_read(&fscache_n_no_create_space), + atomic_read(&fscache_n_culled)); seq_printf(m, "IO : rd=%u wr=%u\n", atomic_read(&fscache_n_read), diff --git a/include/linux/fscache-cache.h b/include/linux/fscache-cache.h index 007e47f38610..a174cedf4d90 100644 --- a/include/linux/fscache-cache.h +++ b/include/linux/fscache-cache.h @@ -188,15 +188,18 @@ extern atomic_t fscache_n_read; extern atomic_t fscache_n_write; extern atomic_t fscache_n_no_write_space; extern atomic_t fscache_n_no_create_space; +extern atomic_t fscache_n_culled; #define fscache_count_read() atomic_inc(&fscache_n_read) #define fscache_count_write() atomic_inc(&fscache_n_write) #define fscache_count_no_write_space() atomic_inc(&fscache_n_no_write_space) #define fscache_count_no_create_space() atomic_inc(&fscache_n_no_create_space) +#define fscache_count_culled() atomic_inc(&fscache_n_culled) #else #define fscache_count_read() do {} while(0) #define fscache_count_write() do {} while(0) #define fscache_count_no_write_space() do {} while(0) #define fscache_count_no_create_space() do {} while(0) +#define fscache_count_culled() do {} while(0) #endif #endif /* _LINUX_FSCACHE_CACHE_H */
