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author | David Howells <dhowells@redhat.com> | 2018-04-04 15:41:27 +0300 |
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committer | David Howells <dhowells@redhat.com> | 2018-04-04 15:41:27 +0300 |
commit | a18feb55769b705a44c4107786c4045eae2e87b6 (patch) | |
tree | 3db7d160e672aa9f16a0437b767b3d3bbb10ecc8 /fs/fscache/cookie.c | |
parent | 2c98425720233ae3e135add0c7e869b32913502f (diff) | |
download | linux-a18feb55769b705a44c4107786c4045eae2e87b6.tar.xz |
fscache: Add tracepoints
Add some tracepoints to fscache:
(*) fscache_cookie - Tracks a cookie's usage count.
(*) fscache_netfs - Logs registration of a network filesystem, including
the pointer to the cookie allocated.
(*) fscache_acquire - Logs cookie acquisition.
(*) fscache_relinquish - Logs cookie relinquishment.
(*) fscache_enable - Logs enablement of a cookie.
(*) fscache_disable - Logs disablement of a cookie.
(*) fscache_osm - Tracks execution of states in the object state machine.
and cachefiles:
(*) cachefiles_ref - Tracks a cachefiles object's usage count.
(*) cachefiles_lookup - Logs result of lookup_one_len().
(*) cachefiles_mkdir - Logs result of vfs_mkdir().
(*) cachefiles_create - Logs result of vfs_create().
(*) cachefiles_unlink - Logs calls to vfs_unlink().
(*) cachefiles_rename - Logs calls to vfs_rename().
(*) cachefiles_mark_active - Logs an object becoming active.
(*) cachefiles_wait_active - Logs a wait for an old object to be
destroyed.
(*) cachefiles_mark_inactive - Logs an object becoming inactive.
(*) cachefiles_mark_buried - Logs the burial of an object.
Signed-off-by: David Howells <dhowells@redhat.com>
Diffstat (limited to 'fs/fscache/cookie.c')
-rw-r--r-- | fs/fscache/cookie.c | 46 |
1 files changed, 29 insertions, 17 deletions
diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c index 98d22f495cd8..20bc3341f113 100644 --- a/fs/fscache/cookie.c +++ b/fs/fscache/cookie.c @@ -101,7 +101,7 @@ struct fscache_cookie *__fscache_acquire_cookie( */ atomic_set(&cookie->n_active, 1); - atomic_inc(&parent->usage); + fscache_cookie_get(parent, fscache_cookie_get_acquire_parent); atomic_inc(&parent->n_children); cookie->def = def; @@ -125,6 +125,8 @@ struct fscache_cookie *__fscache_acquire_cookie( break; } + trace_fscache_acquire(cookie); + if (enable) { /* if the object is an index then we need do nothing more here * - we create indices on disk when we need them as an index @@ -134,7 +136,8 @@ struct fscache_cookie *__fscache_acquire_cookie( set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags); } else { atomic_dec(&parent->n_children); - __fscache_cookie_put(cookie); + fscache_cookie_put(cookie, + fscache_cookie_put_acquire_nobufs); fscache_stat(&fscache_n_acquires_nobufs); _leave(" = NULL"); return NULL; @@ -159,6 +162,8 @@ void __fscache_enable_cookie(struct fscache_cookie *cookie, { _enter("%p", cookie); + trace_fscache_enable(cookie); + wait_on_bit_lock(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK, TASK_UNINTERRUPTIBLE); @@ -318,7 +323,7 @@ static int fscache_alloc_object(struct fscache_cache *cache, * attached to the cookie */ if (fscache_attach_object(cookie, object) < 0) { fscache_stat(&fscache_n_cop_put_object); - cache->ops->put_object(object); + cache->ops->put_object(object, fscache_obj_put_attach_fail); fscache_stat_d(&fscache_n_cop_put_object); } @@ -338,7 +343,7 @@ object_already_extant: error_put: fscache_stat(&fscache_n_cop_put_object); - cache->ops->put_object(object); + cache->ops->put_object(object, fscache_obj_put_alloc_fail); fscache_stat_d(&fscache_n_cop_put_object); error: _leave(" = %d", ret); @@ -398,7 +403,7 @@ static int fscache_attach_object(struct fscache_cookie *cookie, /* attach to the cookie */ object->cookie = cookie; - atomic_inc(&cookie->usage); + fscache_cookie_get(cookie, fscache_cookie_get_attach_object); hlist_add_head(&object->cookie_link, &cookie->backing_objects); fscache_objlist_add(object); @@ -516,6 +521,8 @@ void __fscache_disable_cookie(struct fscache_cookie *cookie, bool invalidate) _enter("%p,%u", cookie, invalidate); + trace_fscache_disable(cookie); + ASSERTCMP(atomic_read(&cookie->n_active), >, 0); if (atomic_read(&cookie->n_children) != 0) { @@ -601,6 +608,8 @@ void __fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire) cookie, cookie->def->name, cookie->netfs_data, atomic_read(&cookie->n_active), retire); + trace_fscache_relinquish(cookie, retire); + /* No further netfs-accessing operations on this cookie permitted */ if (test_and_set_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags)) BUG(); @@ -620,35 +629,38 @@ void __fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire) /* Dispose of the netfs's link to the cookie */ ASSERTCMP(atomic_read(&cookie->usage), >, 0); - fscache_cookie_put(cookie); + fscache_cookie_put(cookie, fscache_cookie_put_relinquish); _leave(""); } EXPORT_SYMBOL(__fscache_relinquish_cookie); /* - * destroy a cookie + * Drop a reference to a cookie. */ -void __fscache_cookie_put(struct fscache_cookie *cookie) +void fscache_cookie_put(struct fscache_cookie *cookie, + enum fscache_cookie_trace where) { struct fscache_cookie *parent; + int usage; _enter("%p", cookie); - for (;;) { - _debug("FREE COOKIE %p", cookie); + do { + usage = atomic_dec_return(&cookie->usage); + trace_fscache_cookie(cookie, where, usage); + + if (usage > 0) + return; + BUG_ON(usage < 0); + parent = cookie->parent; BUG_ON(!hlist_empty(&cookie->backing_objects)); kmem_cache_free(fscache_cookie_jar, cookie); - if (!parent) - break; - cookie = parent; - BUG_ON(atomic_read(&cookie->usage) <= 0); - if (!atomic_dec_and_test(&cookie->usage)) - break; - } + where = fscache_cookie_put_parent; + } while (cookie); _leave(""); } |