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: David Howells <dhowells@redhat.com>

1 files changed, 23 insertions, 6 deletions

diff --git a/fs/fscache/page.c b/fs/fscache/page.c
index c5973e38ce39..250dfd34c07b 100644
--- a/fs/fscache/page.c
+++ b/fs/fscache/page.c
@@ -71,7 +71,9 @@ static void fscache_attr_changed_op(struct fscache_operation *op)
 
         if (fscache_object_is_active(object)) {
                 fscache_set_op_state(op, "CallFS");
+                fscache_stat(&fscache_n_cop_attr_changed);
                 ret = object->cache->ops->attr_changed(object);
+                fscache_stat_d(&fscache_n_cop_attr_changed);
                 fscache_set_op_state(op, "Done");
                 if (ret < 0)
                         fscache_abort_object(object);
@@ -300,11 +302,15 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
 
         /* ask the cache to honour the operation */
         if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) {
+                fscache_stat(&fscache_n_cop_allocate_page);
                 ret = object->cache->ops->allocate_page(op, page, gfp);
+                fscache_stat_d(&fscache_n_cop_allocate_page);
                 if (ret == 0)
                         ret = -ENODATA;
         } else {
+                fscache_stat(&fscache_n_cop_read_or_alloc_page);
                 ret = object->cache->ops->read_or_alloc_page(op, page, gfp);
+                fscache_stat_d(&fscache_n_cop_read_or_alloc_page);
         }
 
         if (ret == -ENOMEM)
@@ -358,7 +364,6 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
                                   void *context,
                                   gfp_t gfp)
 {
-        fscache_pages_retrieval_func_t func;
         struct fscache_retrieval *op;
         struct fscache_object *object;
         int ret;
@@ -413,11 +418,17 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
         }
 
         /* ask the cache to honour the operation */
-        if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags))
-                func = object->cache->ops->allocate_pages;
-        else
-                func = object->cache->ops->read_or_alloc_pages;
-        ret = func(op, pages, nr_pages, gfp);
+        if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) {
+                fscache_stat(&fscache_n_cop_allocate_pages);
+                ret = object->cache->ops->allocate_pages(
+                        op, pages, nr_pages, gfp);
+                fscache_stat_d(&fscache_n_cop_allocate_pages);
+        } else {
+                fscache_stat(&fscache_n_cop_read_or_alloc_pages);
+                ret = object->cache->ops->read_or_alloc_pages(
+                        op, pages, nr_pages, gfp);
+                fscache_stat_d(&fscache_n_cop_read_or_alloc_pages);
+        }
 
         if (ret == -ENOMEM)
                 fscache_stat(&fscache_n_retrievals_nomem);
@@ -500,7 +511,9 @@ int __fscache_alloc_page(struct fscache_cookie *cookie,
         }
 
         /* ask the cache to honour the operation */
+        fscache_stat(&fscache_n_cop_allocate_page);
         ret = object->cache->ops->allocate_page(op, page, gfp);
+        fscache_stat_d(&fscache_n_cop_allocate_page);
 
         if (ret < 0)
                 fscache_stat(&fscache_n_allocs_nobufs);
@@ -578,7 +591,9 @@ static void fscache_write_op(struct fscache_operation *_op)
 
         if (page) {
                 fscache_set_op_state(&op->op, "Store");
+                fscache_stat(&fscache_n_cop_write_page);
                 ret = object->cache->ops->write_page(op, page);
+                fscache_stat_d(&fscache_n_cop_write_page);
                 fscache_set_op_state(&op->op, "EndWrite");
                 fscache_end_page_write(cookie, page);
                 page_cache_release(page);
@@ -786,7 +801,9 @@ void __fscache_uncache_page(struct fscache_cookie *cookie, struct page *page)
         if (TestClearPageFsCache(page) &&
             object->cache->ops->uncache_page) {
                 /* the cache backend releases the cookie lock */
+                fscache_stat(&fscache_n_cop_uncache_page);
                 object->cache->ops->uncache_page(object, page);
+                fscache_stat_d(&fscache_n_cop_uncache_page);
                 goto done;
         }