diff options
author | Kent Overstreet <kent.overstreet@gmail.com> | 2021-12-28 04:45:07 +0300 |
---|---|---|
committer | Kent Overstreet <kent.overstreet@linux.dev> | 2023-10-23 00:09:20 +0300 |
commit | c7ce813fe49a58344ba11219c0bd3a2fdb2e8b9e (patch) | |
tree | 7313f7c84a4578da61d9ac25836cf36fd5b13c93 /fs/bcachefs/btree_cache.c | |
parent | d93cf6858fe67a84e90af76994a2fe4b390c0a0b (diff) | |
download | linux-c7ce813fe49a58344ba11219c0bd3a2fdb2e8b9e.tar.xz |
bcachefs: Add a tracepoint for the btree cache shrinker
This is to help with diagnosing why the btree node can doesn't seem to
be shrinking - we've had issues in the past with granularity/batch size,
since btree nodes are so big.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Diffstat (limited to 'fs/bcachefs/btree_cache.c')
-rw-r--r-- | fs/bcachefs/btree_cache.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c index 5bf493a315ca..40061887f5d8 100644 --- a/fs/bcachefs/btree_cache.c +++ b/fs/bcachefs/btree_cache.c @@ -275,6 +275,7 @@ static unsigned long bch2_btree_cache_scan(struct shrinker *shrink, unsigned long touched = 0; unsigned long freed = 0; unsigned i, flags; + unsigned long ret = SHRINK_STOP; if (bch2_btree_shrinker_disabled) return SHRINK_STOP; @@ -283,7 +284,7 @@ static unsigned long bch2_btree_cache_scan(struct shrinker *shrink, if (sc->gfp_mask & __GFP_FS) mutex_lock(&bc->lock); else if (!mutex_trylock(&bc->lock)) - return -1; + goto out_norestore; flags = memalloc_nofs_save(); @@ -358,8 +359,14 @@ restart: mutex_unlock(&bc->lock); out: + ret = (unsigned long) freed * btree_pages(c); memalloc_nofs_restore(flags); - return (unsigned long) freed * btree_pages(c); +out_norestore: + trace_btree_cache_scan(sc->nr_to_scan, + sc->nr_to_scan / btree_pages(c), + btree_cache_can_free(bc), + ret); + return ret; } static unsigned long bch2_btree_cache_count(struct shrinker *shrink, |