From 3929eca769b5a231010b4978acc61c0735da198f Mon Sep 17 00:00:00 2001 From: David Howells Date: Thu, 21 Oct 2021 21:58:29 +0100 Subject: fscache, cachefiles: Display stats of no-space events Add stat counters of no-space events that caused caching not to happen and display in /proc/fs/fscache/stats. Signed-off-by: David Howells Reviewed-by: Jeff Layton cc: linux-cachefs@redhat.com Link: https://lore.kernel.org/r/163819653216.215744.17210522251617386509.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/163906958369.143852.7257100711818401748.stgit@warthog.procyon.org.uk/ # v2 Link: https://lore.kernel.org/r/163967166917.1823006.14842444049198947892.stgit@warthog.procyon.org.uk/ # v3 Link: https://lore.kernel.org/r/164021566184.640689.4417328329632709265.stgit@warthog.procyon.org.uk/ # v4 --- fs/cachefiles/cache.c | 18 +++++++++++++++--- fs/cachefiles/daemon.c | 2 +- fs/cachefiles/internal.h | 11 +++++++++-- fs/cachefiles/io.c | 7 +++++-- fs/cachefiles/namei.c | 6 ++++-- 5 files changed, 34 insertions(+), 10 deletions(-) (limited to 'fs/cachefiles') diff --git a/fs/cachefiles/cache.c b/fs/cachefiles/cache.c index e2cbbc08bad9..809519286335 100644 --- a/fs/cachefiles/cache.c +++ b/fs/cachefiles/cache.c @@ -147,7 +147,7 @@ int cachefiles_add_cache(struct cachefiles_cache *cache) pr_info("File cache on %s registered\n", cache_cookie->name); /* check how much space the cache has */ - cachefiles_has_space(cache, 0, 0); + cachefiles_has_space(cache, 0, 0, cachefiles_has_space_check); cachefiles_end_secure(cache, saved_cred); _leave(" = 0 [%px]", cache->cache); return 0; @@ -175,7 +175,8 @@ error_getsec: * cache */ int cachefiles_has_space(struct cachefiles_cache *cache, - unsigned fnr, unsigned bnr) + unsigned fnr, unsigned bnr, + enum cachefiles_has_space_for reason) { struct kstatfs stats; u64 b_avail, b_writing; @@ -233,7 +234,7 @@ int cachefiles_has_space(struct cachefiles_cache *cache, ret = -ENOBUFS; if (stats.f_ffree < cache->fstop || b_avail < cache->bstop) - goto begin_cull; + goto stop_and_begin_cull; ret = 0; if (stats.f_ffree < cache->fcull || @@ -252,6 +253,17 @@ int cachefiles_has_space(struct cachefiles_cache *cache, //_leave(" = 0"); return 0; +stop_and_begin_cull: + switch (reason) { + case cachefiles_has_space_for_write: + fscache_count_no_write_space(); + break; + case cachefiles_has_space_for_create: + fscache_count_no_create_space(); + break; + default: + break; + } begin_cull: if (!test_and_set_bit(CACHEFILES_CULLING, &cache->flags)) { _debug("### CULL CACHE ###"); diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 45af558a696e..40a792421fc1 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -170,7 +170,7 @@ static ssize_t cachefiles_daemon_read(struct file *file, char __user *_buffer, return 0; /* check how much space the cache has */ - cachefiles_has_space(cache, 0, 0); + cachefiles_has_space(cache, 0, 0, cachefiles_has_space_check); /* summarise */ f_released = atomic_xchg(&cache->f_released, 0); diff --git a/fs/cachefiles/internal.h b/fs/cachefiles/internal.h index abdd1b66f6b9..8dd54d9375b6 100644 --- a/fs/cachefiles/internal.h +++ b/fs/cachefiles/internal.h @@ -130,10 +130,17 @@ static inline void cachefiles_state_changed(struct cachefiles_cache *cache) * cache.c */ extern int cachefiles_add_cache(struct cachefiles_cache *cache); -extern int cachefiles_has_space(struct cachefiles_cache *cache, - unsigned fnr, unsigned bnr); extern void cachefiles_withdraw_cache(struct cachefiles_cache *cache); +enum cachefiles_has_space_for { + cachefiles_has_space_check, + cachefiles_has_space_for_write, + cachefiles_has_space_for_create, +}; +extern int cachefiles_has_space(struct cachefiles_cache *cache, + unsigned fnr, unsigned bnr, + enum cachefiles_has_space_for reason); + /* * daemon.c */ diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c index 6f4dce0cfc36..60b1eac2ce78 100644 --- a/fs/cachefiles/io.c +++ b/fs/cachefiles/io.c @@ -468,7 +468,8 @@ static int __cachefiles_prepare_write(struct netfs_cache_resources *cres, * space, we need to see if it's fully allocated. If it's not, we may * want to cull it. */ - if (cachefiles_has_space(cache, 0, *_len / PAGE_SIZE) == 0) + if (cachefiles_has_space(cache, 0, *_len / PAGE_SIZE, + cachefiles_has_space_check) == 0) return 0; /* Enough space to simply overwrite the whole block */ pos = cachefiles_inject_read_error(); @@ -483,6 +484,7 @@ static int __cachefiles_prepare_write(struct netfs_cache_resources *cres, return 0; /* Fully allocated */ /* Partially allocated, but insufficient space: cull. */ + fscache_count_no_write_space(); ret = cachefiles_inject_remove_error(); if (ret == 0) ret = vfs_fallocate(file, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, @@ -498,7 +500,8 @@ static int __cachefiles_prepare_write(struct netfs_cache_resources *cres, return ret; check_space: - return cachefiles_has_space(cache, 0, *_len / PAGE_SIZE); + return cachefiles_has_space(cache, 0, *_len / PAGE_SIZE, + cachefiles_has_space_for_write); } static int cachefiles_prepare_write(struct netfs_cache_resources *cres, diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c index b549e9f79c01..ab3ca598acac 100644 --- a/fs/cachefiles/namei.c +++ b/fs/cachefiles/namei.c @@ -115,7 +115,8 @@ retry: /* we need to create the subdir if it doesn't exist yet */ if (d_is_negative(subdir)) { - ret = cachefiles_has_space(cache, 1, 0); + ret = cachefiles_has_space(cache, 1, 0, + cachefiles_has_space_for_create); if (ret < 0) goto mkdir_error; @@ -513,7 +514,8 @@ static bool cachefiles_create_file(struct cachefiles_object *object) struct file *file; int ret; - ret = cachefiles_has_space(object->volume->cache, 1, 0); + ret = cachefiles_has_space(object->volume->cache, 1, 0, + cachefiles_has_space_for_create); if (ret < 0) return false; -- cgit v1.2.3