diff options
author | Daniel Hill <daniel@gluo.nz> | 2022-09-30 16:37:15 +1300 |
---|---|---|
committer | Kent Overstreet <kent.overstreet@linux.dev> | 2023-06-21 03:32:17 -0400 |
commit | 2018c2c75988f7c5e3e6802e7752acffc4c44c49 (patch) | |
tree | acbeebc27da62a4559cdad2473c686adeddab61e | |
parent | baa50381ececee802b4662d831d8dd19b2162073 (diff) |
bcachefs: add counters for failed shrinker reclaim
These counters should help us debug OOM issues.
Signed-off-by: Daniel Hill <daniel@gluo.nz>
-rw-r--r-- | fs/bcachefs/btree_cache.c | 91 | ||||
-rw-r--r-- | fs/bcachefs/btree_cache.h | 2 | ||||
-rw-r--r-- | fs/bcachefs/btree_types.h | 10 | ||||
-rw-r--r-- | fs/bcachefs/sysfs.c | 2 |
4 files changed, 81 insertions, 24 deletions
diff --git a/fs/bcachefs/btree_cache.c b/fs/bcachefs/btree_cache.c index 9f4b4967d660..e5816efecf26 100644 --- a/fs/bcachefs/btree_cache.c +++ b/fs/bcachefs/btree_cache.c @@ -15,6 +15,12 @@ #include <linux/sched/mm.h> #include <linux/seq_buf.h> +#define BTREE_CACHE_NOT_FREED_INCREMENT(counter) \ +do { \ + if (shrinker_counter) \ + bc->not_freed_##counter++; \ +} while (0) + const char * const bch2_btree_node_flags[] = { #define x(f) #f, BTREE_FLAGS() @@ -200,7 +206,7 @@ static inline struct btree *btree_cache_find(struct btree_cache *bc, * this version is for btree nodes that have already been freed (we're not * reaping a real btree node) */ -static int __btree_node_reclaim(struct bch_fs *c, struct btree *b, bool flush) +static int __btree_node_reclaim(struct bch_fs *c, struct btree *b, bool flush, bool shrinker_counter) { struct btree_cache *bc = &c->btree_cache; int ret = 0; @@ -210,38 +216,64 @@ wait_on_io: if (b->flags & ((1U << BTREE_NODE_dirty)| (1U << BTREE_NODE_read_in_flight)| (1U << BTREE_NODE_write_in_flight))) { - if (!flush) + if (!flush) { + if (btree_node_dirty(b)) + BTREE_CACHE_NOT_FREED_INCREMENT(dirty); + else if (btree_node_read_in_flight(b)) + BTREE_CACHE_NOT_FREED_INCREMENT(read_in_flight); + else if (btree_node_write_in_flight(b)) + BTREE_CACHE_NOT_FREED_INCREMENT(write_in_flight); return -BCH_ERR_ENOMEM_btree_node_reclaim; + } /* XXX: waiting on IO with btree cache lock held */ bch2_btree_node_wait_on_read(b); bch2_btree_node_wait_on_write(b); } - if (!six_trylock_intent(&b->c.lock)) + if (!six_trylock_intent(&b->c.lock)) { + BTREE_CACHE_NOT_FREED_INCREMENT(lock_intent); return -BCH_ERR_ENOMEM_btree_node_reclaim; + } - if (!six_trylock_write(&b->c.lock)) + if (!six_trylock_write(&b->c.lock)) { + BTREE_CACHE_NOT_FREED_INCREMENT(lock_write); goto out_unlock_intent; + } /* recheck under lock */ if (b->flags & ((1U << BTREE_NODE_read_in_flight)| (1U << BTREE_NODE_write_in_flight))) { - if (!flush) + if (!flush) { + if (btree_node_read_in_flight(b)) + BTREE_CACHE_NOT_FREED_INCREMENT(read_in_flight); + else if (btree_node_write_in_flight(b)) + BTREE_CACHE_NOT_FREED_INCREMENT(write_in_flight); goto out_unlock; + } six_unlock_write(&b->c.lock); six_unlock_intent(&b->c.lock); goto wait_on_io; } - if (btree_node_noevict(b) || - btree_node_write_blocked(b) || - btree_node_will_make_reachable(b)) + if (btree_node_noevict(b)) { + BTREE_CACHE_NOT_FREED_INCREMENT(noevict); + goto out_unlock; + } + if (btree_node_write_blocked(b)) { + BTREE_CACHE_NOT_FREED_INCREMENT(write_blocked); + goto out_unlock; + } + if (btree_node_will_make_reachable(b)) { + BTREE_CACHE_NOT_FREED_INCREMENT(will_make_reachable); goto out_unlock; + } if (btree_node_dirty(b)) { - if (!flush) + if (!flush) { + BTREE_CACHE_NOT_FREED_INCREMENT(dirty); goto out_unlock; + } /* * Using the underscore version because we don't want to compact * bsets after the write, since this node is about to be evicted @@ -271,14 +303,14 @@ out_unlock_intent: goto out; } -static int btree_node_reclaim(struct bch_fs *c, struct btree *b) +static int btree_node_reclaim(struct bch_fs *c, struct btree *b, bool shrinker_counter) { - return __btree_node_reclaim(c, b, false); + return __btree_node_reclaim(c, b, false, shrinker_counter); } static int btree_node_write_and_reclaim(struct bch_fs *c, struct btree *b) { - return __btree_node_reclaim(c, b, true); + return __btree_node_reclaim(c, b, true, false); } static unsigned long bch2_btree_cache_scan(struct shrinker *shrink, @@ -327,11 +359,12 @@ static unsigned long bch2_btree_cache_scan(struct shrinker *shrink, if (touched >= nr) goto out; - if (!btree_node_reclaim(c, b)) { + if (!btree_node_reclaim(c, b, true)) { btree_node_data_free(c, b); six_unlock_write(&b->c.lock); six_unlock_intent(&b->c.lock); freed++; + bc->freed++; } } restart: @@ -340,9 +373,11 @@ restart: if (btree_node_accessed(b)) { clear_btree_node_accessed(b); - } else if (!btree_node_reclaim(c, b)) { + bc->not_freed_access_bit++; + } else if (!btree_node_reclaim(c, b, true)) { freed++; btree_node_data_free(c, b); + bc->freed++; bch2_btree_node_hash_remove(bc, b); six_unlock_write(&b->c.lock); @@ -401,7 +436,7 @@ static void bch2_btree_cache_shrinker_to_text(struct seq_buf *s, struct shrinker size_t buflen = seq_buf_get_buf(s, &cbuf); struct printbuf out = PRINTBUF_EXTERN(cbuf, buflen); - bch2_btree_cache_to_text(&out, c); + bch2_btree_cache_to_text(&out, &c->btree_cache); seq_buf_commit(s, out.pos); } @@ -560,7 +595,7 @@ static struct btree *btree_node_cannibalize(struct bch_fs *c) struct btree *b; list_for_each_entry_reverse(b, &bc->live, list) - if (!btree_node_reclaim(c, b)) + if (!btree_node_reclaim(c, b, false)) return b; while (1) { @@ -596,7 +631,7 @@ struct btree *bch2_btree_node_mem_alloc(struct btree_trans *trans, bool pcpu_rea * disk node. Check the freed list before allocating a new one: */ list_for_each_entry(b, freed, list) - if (!btree_node_reclaim(c, b)) { + if (!btree_node_reclaim(c, b, false)) { list_del_init(&b->list); goto got_node; } @@ -622,7 +657,7 @@ got_node: * the list. Check if there's any freed nodes there: */ list_for_each_entry(b2, &bc->freeable, list) - if (!btree_node_reclaim(c, b2)) { + if (!btree_node_reclaim(c, b2, false)) { swap(b->data, b2->data); swap(b->aux_data, b2->aux_data); btree_node_to_freedlist(bc, b2); @@ -1219,9 +1254,21 @@ void bch2_btree_node_to_text(struct printbuf *out, struct bch_fs *c, stats.failed); } -void bch2_btree_cache_to_text(struct printbuf *out, const struct bch_fs *c) +void bch2_btree_cache_to_text(struct printbuf *out, const struct btree_cache *bc) { - prt_printf(out, "nr nodes:\t\t%u\n", c->btree_cache.used); - prt_printf(out, "nr dirty:\t\t%u\n", atomic_read(&c->btree_cache.dirty)); - prt_printf(out, "cannibalize lock:\t%p\n", c->btree_cache.alloc_lock); + prt_printf(out, "nr nodes:\t\t%u\n", bc->used); + prt_printf(out, "nr dirty:\t\t%u\n", atomic_read(&bc->dirty)); + prt_printf(out, "cannibalize lock:\t%p\n", bc->alloc_lock); + + prt_printf(out, "freed:\t\t\t\t%u\n", bc->freed); + prt_printf(out, "not freed, dirty:\t\t%u\n", bc->not_freed_dirty); + prt_printf(out, "not freed, write in flight:\t%u\n", bc->not_freed_write_in_flight); + prt_printf(out, "not freed, read in flight:\t%u\n", bc->not_freed_read_in_flight); + prt_printf(out, "not freed, lock intent failed:\t%u\n", bc->not_freed_lock_intent); + prt_printf(out, "not freed, lock write failed:\t%u\n", bc->not_freed_lock_write); + prt_printf(out, "not freed, access bit:\t\t%u\n", bc->not_freed_access_bit); + prt_printf(out, "not freed, no evict failed:\t%u\n", bc->not_freed_noevict); + prt_printf(out, "not freed, write blocked:\t%u\n", bc->not_freed_write_blocked); + prt_printf(out, "not freed, will make reachable:\t%u\n", bc->not_freed_will_make_reachable); + } diff --git a/fs/bcachefs/btree_cache.h b/fs/bcachefs/btree_cache.h index ea375ae25a70..4900ed45422e 100644 --- a/fs/bcachefs/btree_cache.h +++ b/fs/bcachefs/btree_cache.h @@ -101,6 +101,6 @@ static inline unsigned btree_blocks(struct bch_fs *c) void bch2_btree_node_to_text(struct printbuf *, struct bch_fs *, const struct btree *); -void bch2_btree_cache_to_text(struct printbuf *, const struct bch_fs *); +void bch2_btree_cache_to_text(struct printbuf *, const struct btree_cache *); #endif /* _BCACHEFS_BTREE_CACHE_H */ diff --git a/fs/bcachefs/btree_types.h b/fs/bcachefs/btree_types.h index 887f6151ef9d..d4ff72128ad3 100644 --- a/fs/bcachefs/btree_types.h +++ b/fs/bcachefs/btree_types.h @@ -162,6 +162,16 @@ struct btree_cache { /* Number of elements in live + freeable lists */ unsigned used; unsigned reserve; + unsigned freed; + unsigned not_freed_lock_intent; + unsigned not_freed_lock_write; + unsigned not_freed_dirty; + unsigned not_freed_read_in_flight; + unsigned not_freed_write_in_flight; + unsigned not_freed_noevict; + unsigned not_freed_write_blocked; + unsigned not_freed_will_make_reachable; + unsigned not_freed_access_bit; atomic_t dirty; struct shrinker shrink; diff --git a/fs/bcachefs/sysfs.c b/fs/bcachefs/sysfs.c index 54e1071ecfeb..8897eb54e54f 100644 --- a/fs/bcachefs/sysfs.c +++ b/fs/bcachefs/sysfs.c @@ -429,7 +429,7 @@ SHOW(bch2_fs) bch2_btree_updates_to_text(out, c); if (attr == &sysfs_btree_cache) - bch2_btree_cache_to_text(out, c); + bch2_btree_cache_to_text(out, &c->btree_cache); if (attr == &sysfs_btree_key_cache) bch2_btree_key_cache_to_text(out, &c->btree_key_cache); |