fscache, cachefiles: Display stat of culling events

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@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819654165.215744.3797804661644212436.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906961387.143852.9291157239960289090.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967168266.1823006.14436200166581605746.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021567619.640689.4339228906248763197.stgit@warthog.procyon.org.uk/ # v4
This commit is contained in:
David Howells 2021-10-22 09:17:58 +01:00
parent 3929eca769
commit 9f08ebc343
3 changed files with 9 additions and 2 deletions

View File

@ -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;

View File

@ -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),

View File

@ -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 */