Commit 52bd75fd authored by David Howells's avatar David Howells
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FS-Cache: Add counters for entry/exit to/from cache operation functions 



Count entries to and exits from cache operation table functions.  Maintain
these as a single counter that's added to or removed from as appropriate.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent 4fbf4291

Documentation/filesystems/caching/fscache.txt

+16 −0
Original line number Diff line number Diff line
@@ -274,6 +274,22 @@ proc files. 
		dfr=N	Number of async ops queued for deferred release

		rel=N	Number of async ops released

		gc=N	Number of deferred-release async ops garbage collected

	CacheOp	alo=N	Number of in-progress alloc_object() cache ops

		luo=N	Number of in-progress lookup_object() cache ops

		luc=N	Number of in-progress lookup_complete() cache ops

		gro=N	Number of in-progress grab_object() cache ops

		upo=N	Number of in-progress update_object() cache ops

		dro=N	Number of in-progress drop_object() cache ops

		pto=N	Number of in-progress put_object() cache ops

		syn=N	Number of in-progress sync_cache() cache ops

		atc=N	Number of in-progress attr_changed() cache ops

		rap=N	Number of in-progress read_or_alloc_page() cache ops

		ras=N	Number of in-progress read_or_alloc_pages() cache ops

		alp=N	Number of in-progress allocate_page() cache ops

		als=N	Number of in-progress allocate_pages() cache ops

		wrp=N	Number of in-progress write_page() cache ops

		ucp=N	Number of in-progress uncache_page() cache ops

		dsp=N	Number of in-progress dissociate_pages() cache ops





 (*) /proc/fs/fscache/histogram

fs/fscache/cache.c

+4 −0
Original line number Diff line number Diff line
@@ -381,11 +381,15 @@ void fscache_withdraw_cache(struct fscache_cache *cache) 


	/* make sure all pages pinned by operations on behalf of the netfs are

	 * written to disk */

	fscache_stat(&fscache_n_cop_sync_cache);

	cache->ops->sync_cache(cache);

	fscache_stat_d(&fscache_n_cop_sync_cache);



	/* dissociate all the netfs pages backed by this cache from the block

	 * mappings in the cache */

	fscache_stat(&fscache_n_cop_dissociate_pages);

	cache->ops->dissociate_pages(cache);

	fscache_stat_d(&fscache_n_cop_dissociate_pages);



	/* we now have to destroy all the active objects pertaining to this

	 * cache - which we do by passing them off to thread pool to be

fs/fscache/cookie.c

+8 −1
Original line number Diff line number Diff line
@@ -249,7 +249,9 @@ static int fscache_alloc_object(struct fscache_cache *cache, 


	/* ask the cache to allocate an object (we may end up with duplicate

	 * objects at this stage, but we sort that out later) */

	fscache_stat(&fscache_n_cop_alloc_object);

	object = cache->ops->alloc_object(cache, cookie);

	fscache_stat_d(&fscache_n_cop_alloc_object);

	if (IS_ERR(object)) {

		fscache_stat(&fscache_n_object_no_alloc);

		ret = PTR_ERR(object);
@@ -270,8 +272,11 @@ static int fscache_alloc_object(struct fscache_cache *cache, 
	/* only attach if we managed to allocate all we needed, otherwise

	 * discard the object we just allocated and instead use the one

	 * attached to the cookie */

	if (fscache_attach_object(cookie, object) < 0)

	if (fscache_attach_object(cookie, object) < 0) {

		fscache_stat(&fscache_n_cop_put_object);

		cache->ops->put_object(object);

		fscache_stat_d(&fscache_n_cop_put_object);

	}



	_leave(" = 0");

	return 0;
@@ -287,7 +292,9 @@ object_already_extant: 
	return 0;



error_put:

	fscache_stat(&fscache_n_cop_put_object);

	cache->ops->put_object(object);

	fscache_stat_d(&fscache_n_cop_put_object);

error:

	_leave(" = %d", ret);

	return ret;

fs/fscache/internal.h

+22 −0
Original line number Diff line number Diff line
@@ -208,11 +208,33 @@ extern atomic_t fscache_n_checkaux_okay; 
extern atomic_t fscache_n_checkaux_update;

extern atomic_t fscache_n_checkaux_obsolete;



extern atomic_t fscache_n_cop_alloc_object;

extern atomic_t fscache_n_cop_lookup_object;

extern atomic_t fscache_n_cop_lookup_complete;

extern atomic_t fscache_n_cop_grab_object;

extern atomic_t fscache_n_cop_update_object;

extern atomic_t fscache_n_cop_drop_object;

extern atomic_t fscache_n_cop_put_object;

extern atomic_t fscache_n_cop_sync_cache;

extern atomic_t fscache_n_cop_attr_changed;

extern atomic_t fscache_n_cop_read_or_alloc_page;

extern atomic_t fscache_n_cop_read_or_alloc_pages;

extern atomic_t fscache_n_cop_allocate_page;

extern atomic_t fscache_n_cop_allocate_pages;

extern atomic_t fscache_n_cop_write_page;

extern atomic_t fscache_n_cop_uncache_page;

extern atomic_t fscache_n_cop_dissociate_pages;



static inline void fscache_stat(atomic_t *stat)

{

	atomic_inc(stat);

}



static inline void fscache_stat_d(atomic_t *stat)

{

	atomic_dec(stat);

}



extern const struct file_operations fscache_stats_fops;

#else

fs/fscache/object.c

+24 −2
Original line number Diff line number Diff line
@@ -144,13 +144,17 @@ static void fscache_object_state_machine(struct fscache_object *object) 
	case FSCACHE_OBJECT_UPDATING:

		clear_bit(FSCACHE_OBJECT_EV_UPDATE, &object->events);

		fscache_stat(&fscache_n_updates_run);

		fscache_stat(&fscache_n_cop_update_object);

		object->cache->ops->update_object(object);

		fscache_stat_d(&fscache_n_cop_update_object);

		goto active_transit;



		/* handle an object dying during lookup or creation */

	case FSCACHE_OBJECT_LC_DYING:

		object->event_mask &= ~(1 << FSCACHE_OBJECT_EV_UPDATE);

		fscache_stat(&fscache_n_cop_lookup_complete);

		object->cache->ops->lookup_complete(object);

		fscache_stat_d(&fscache_n_cop_lookup_complete);



		spin_lock(&object->lock);

		object->state = FSCACHE_OBJECT_DYING;
@@ -416,7 +420,9 @@ static void fscache_initialise_object(struct fscache_object *object) 
			 * binding on to us, so we need to make sure we don't

			 * add ourself to the list multiple times */

			if (list_empty(&object->dep_link)) {

				fscache_stat(&fscache_n_cop_grab_object);

				object->cache->ops->grab_object(object);

				fscache_stat_d(&fscache_n_cop_grab_object);

				list_add(&object->dep_link,

					 &parent->dependents);
@@ -478,7 +484,9 @@ static void fscache_lookup_object(struct fscache_object *object) 
	       object->cache->tag->name);



	fscache_stat(&fscache_n_object_lookups);

	fscache_stat(&fscache_n_cop_lookup_object);

	object->cache->ops->lookup_object(object);

	fscache_stat_d(&fscache_n_cop_lookup_object);



	if (test_bit(FSCACHE_OBJECT_EV_ERROR, &object->events))

		set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
@@ -602,7 +610,9 @@ static void fscache_object_available(struct fscache_object *object) 
	}

	spin_unlock(&object->lock);



	fscache_stat(&fscache_n_cop_lookup_complete);

	object->cache->ops->lookup_complete(object);

	fscache_stat_d(&fscache_n_cop_lookup_complete);

	fscache_enqueue_dependents(object);



	fscache_hist(fscache_obj_instantiate_histogram, object->lookup_jif);
@@ -625,7 +635,9 @@ static void fscache_drop_object(struct fscache_object *object) 
	list_del_init(&object->cache_link);

	spin_unlock(&cache->object_list_lock);



	fscache_stat(&fscache_n_cop_drop_object);

	cache->ops->drop_object(object);

	fscache_stat_d(&fscache_n_cop_drop_object);



	if (parent) {

		_debug("release parent OBJ%x {%d}",
@@ -640,7 +652,9 @@ static void fscache_drop_object(struct fscache_object *object) 
	}



	/* this just shifts the object release to the slow work processor */

	fscache_stat(&fscache_n_cop_put_object);

	object->cache->ops->put_object(object);

	fscache_stat_d(&fscache_n_cop_put_object);



	_leave("");

}
@@ -730,8 +744,12 @@ static int fscache_object_slow_work_get_ref(struct slow_work *work) 
{

	struct fscache_object *object =

		container_of(work, struct fscache_object, work);

	int ret;



	return object->cache->ops->grab_object(object) ? 0 : -EAGAIN;

	fscache_stat(&fscache_n_cop_grab_object);

	ret = object->cache->ops->grab_object(object) ? 0 : -EAGAIN;

	fscache_stat_d(&fscache_n_cop_grab_object);

	return ret;

}



/*
@@ -742,7 +760,9 @@ static void fscache_object_slow_work_put_ref(struct slow_work *work) 
	struct fscache_object *object =

		container_of(work, struct fscache_object, work);



	return object->cache->ops->put_object(object);

	fscache_stat(&fscache_n_cop_put_object);

	object->cache->ops->put_object(object);

	fscache_stat_d(&fscache_n_cop_put_object);

}



/*
@@ -779,7 +799,9 @@ static void fscache_enqueue_dependents(struct fscache_object *object) 


		/* sort onto appropriate lists */

		fscache_enqueue_object(dep);

		fscache_stat(&fscache_n_cop_put_object);

		dep->cache->ops->put_object(dep);

		fscache_stat_d(&fscache_n_cop_put_object);



		if (!list_empty(&object->dependents))

			cond_resched_lock(&object->lock);