Add some stats to indicate the state of the cookie commit LRU, including an indication of how many are currently on it, how many have been expired, removed (withdrawn/reused) or dropped (relinquished) from it and how long till the next reap happens.
Signed-off-by: David Howells <[email protected]> --- fs/fscache/cookie.c | 10 +++++++++- fs/fscache/internal.h | 5 +++++ fs/fscache/stats.c | 12 ++++++++++++ 3 files changed, 26 insertions(+), 1 deletion(-) diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c index dfc61b2e105d..c6b553609f33 100644 --- a/fs/fscache/cookie.c +++ b/fs/fscache/cookie.c @@ -28,7 +28,7 @@ static LIST_HEAD(fscache_cookies); static DEFINE_RWLOCK(fscache_cookies_lock); static LIST_HEAD(fscache_cookie_lru); static DEFINE_SPINLOCK(fscache_cookie_lru_lock); -static DEFINE_TIMER(fscache_cookie_lru_timer, fscache_cookie_lru_timed_out); +DEFINE_TIMER(fscache_cookie_lru_timer, fscache_cookie_lru_timed_out); static DECLARE_WORK(fscache_cookie_lru_work, fscache_cookie_lru_worker); static const char fscache_cookie_stages[FSCACHE_COOKIE_STAGE__NR] = "-LCAIFMWRD"; unsigned int fscache_lru_cookie_timeout = 10 * HZ; @@ -60,6 +60,8 @@ static void fscache_free_cookie(struct fscache_cookie *cookie) spin_lock(&fscache_cookie_lru_lock); list_del_init(&cookie->commit_link); spin_unlock(&fscache_cookie_lru_lock); + fscache_stat_d(&fscache_n_cookies_lru); + fscache_stat(&fscache_n_cookies_lru_removed); } write_lock(&fscache_cookies_lock); list_del(&cookie->proc_link); @@ -525,6 +527,7 @@ void __fscache_unuse_cookie(struct fscache_cookie *cookie, if (list_empty(&cookie->commit_link)) { fscache_get_cookie(cookie, fscache_cookie_get_lru); list_move_tail(&cookie->commit_link, &fscache_cookie_lru); + fscache_stat(&fscache_n_cookies_lru); } spin_unlock(&fscache_cookie_lru_lock); timer_reduce(&fscache_cookie_lru_timer, @@ -624,10 +627,12 @@ static void fscache_cookie_lru_do_one(struct fscache_cookie *cookie) time_before(jiffies, cookie->unused_at + fscache_lru_cookie_timeout) || atomic_read(&cookie->n_active) > 0) { spin_unlock(&cookie->lock); + fscache_stat(&fscache_n_cookies_lru_removed); } else { __fscache_set_cookie_stage(cookie, FSCACHE_COOKIE_STAGE_COMMITTING); set_bit(FSCACHE_COOKIE_DO_COMMIT, &cookie->flags); spin_unlock(&cookie->lock); + fscache_stat(&fscache_n_cookies_lru_expired); _debug("lru c=%x", cookie->debug_id); __fscache_withdraw_cookie(cookie); } @@ -652,6 +657,7 @@ static void fscache_cookie_lru_worker(struct work_struct *work) } list_del_init(&cookie->commit_link); + fscache_stat_d(&fscache_n_cookies_lru); spin_unlock(&fscache_cookie_lru_lock); fscache_cookie_lru_do_one(cookie); spin_lock(&fscache_cookie_lru_lock); @@ -673,6 +679,8 @@ static void fscache_cookie_drop_from_lru(struct fscache_cookie *cookie) spin_lock(&fscache_cookie_lru_lock); if (!list_empty(&cookie->commit_link)) { list_del_init(&cookie->commit_link); + fscache_stat_d(&fscache_n_cookies_lru); + fscache_stat(&fscache_n_cookies_lru_dropped); need_put = true; } spin_unlock(&fscache_cookie_lru_lock); diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h index f74f7bdea633..62e6a5bbef8e 100644 --- a/fs/fscache/internal.h +++ b/fs/fscache/internal.h @@ -32,6 +32,7 @@ struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache); */ extern struct kmem_cache *fscache_cookie_jar; extern const struct seq_operations fscache_cookies_seq_ops; +extern struct timer_list fscache_cookie_lru_timer; extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix); extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie, @@ -70,6 +71,10 @@ extern atomic_t fscache_n_volumes; extern atomic_t fscache_n_volumes_collision; extern atomic_t fscache_n_volumes_nomem; extern atomic_t fscache_n_cookies; +extern atomic_t fscache_n_cookies_lru; +extern atomic_t fscache_n_cookies_lru_expired; +extern atomic_t fscache_n_cookies_lru_removed; +extern atomic_t fscache_n_cookies_lru_dropped; extern atomic_t fscache_n_retrievals; extern atomic_t fscache_n_retrievals_ok; diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c index 13e90b940bd2..5700e5712018 100644 --- a/fs/fscache/stats.c +++ b/fs/fscache/stats.c @@ -18,6 +18,10 @@ atomic_t fscache_n_volumes; atomic_t fscache_n_volumes_collision; atomic_t fscache_n_volumes_nomem; atomic_t fscache_n_cookies; +atomic_t fscache_n_cookies_lru; +atomic_t fscache_n_cookies_lru_expired; +atomic_t fscache_n_cookies_lru_removed; +atomic_t fscache_n_cookies_lru_dropped; atomic_t fscache_n_retrievals; atomic_t fscache_n_retrievals_ok; @@ -89,6 +93,14 @@ int fscache_stats_show(struct seq_file *m, void *v) atomic_read(&fscache_n_acquires_nobufs), atomic_read(&fscache_n_acquires_oom)); + seq_printf(m, "LRU : n=%u exp=%u rmv=%u drp=%u at=%ld\n", + atomic_read(&fscache_n_cookies_lru), + atomic_read(&fscache_n_cookies_lru_expired), + atomic_read(&fscache_n_cookies_lru_removed), + atomic_read(&fscache_n_cookies_lru_dropped), + timer_pending(&fscache_cookie_lru_timer) ? + fscache_cookie_lru_timer.expires - jiffies : 0); + seq_printf(m, "Invals : n=%u run=%u\n", atomic_read(&fscache_n_invalidates), atomic_read(&fscache_n_invalidates_run)); -- Linux-cachefs mailing list [email protected] https://listman.redhat.com/mailman/listinfo/linux-cachefs
