From db14ac2c81cc03084bfb63f393ac71a36e142266 Mon Sep 17 00:00:00 2001 From: Niels de Vos Date: Tue, 16 May 2017 18:10:16 +0200 Subject: [PATCH 445/473] refcount: return pointer to the structure instead of a counter There are no real users of the counter. It was thought of a handy tool to track and debug refcounting, but it is not used at all. Some parts of the code would benefit from a pointer getting returned instead. Cherry picked from commit 2f0e9ab1ef271132b8b7b1af25e23ac7bb0720c8: > BUG: 1399780 > Change-Id: I97e52c48420fed61be942ea27ff4849b803eed12 > Signed-off-by: Niels de Vos > Reviewed-on: http://review.gluster.org/15971 > Smoke: Gluster Build System > NetBSD-regression: NetBSD Build System > CentOS-regression: Gluster Build System > Reviewed-by: Xavier Hernandez > Reviewed-by: Kaleb KEITHLEY There has been a slight omission in the backport of change I19d225b39aaa272d9005ba7adc3104c3764f1572. The return value of GF_REF_GET() is used and causes compile warnings. The resulting build with that backport may not function correctly without this change that returns the pointer of the structure with GF_REF_GET(). Change-Id: I97e52c48420fed61be942ea27ff4849b803eed12 BUG: 1450336 Reported-by: Mohammed Rafi KC Signed-off-by: Niels de Vos Reviewed-on: https://code.engineering.redhat.com/gerrit/106356 Reviewed-by: Poornima Gurusiddaiah Reviewed-by: Atin Mukherjee --- libglusterfs/src/refcount.c | 21 +++++++-------------- libglusterfs/src/refcount.h | 10 +++++----- xlators/nfs/server/src/auth-cache.c | 10 ++++++---- 3 files changed, 18 insertions(+), 23 deletions(-) diff --git a/libglusterfs/src/refcount.c b/libglusterfs/src/refcount.c index 96edc10..9d33b73 100644 --- a/libglusterfs/src/refcount.c +++ b/libglusterfs/src/refcount.c @@ -13,7 +13,7 @@ #ifndef REFCOUNT_NEEDS_LOCK -unsigned int +void * _gf_ref_get (gf_ref_t *ref) { unsigned int cnt = __sync_fetch_and_add (&ref->cnt, 1); @@ -27,10 +27,10 @@ _gf_ref_get (gf_ref_t *ref) */ GF_ASSERT (cnt != 0); - return cnt; + return cnt ? ref->data : NULL; } -unsigned int +void _gf_ref_put (gf_ref_t *ref) { unsigned int cnt = __sync_fetch_and_sub (&ref->cnt, 1); @@ -43,18 +43,13 @@ _gf_ref_put (gf_ref_t *ref) */ GF_ASSERT (cnt != 0); - if (cnt == 1 && ref->release) { + if (cnt == 1 && ref->release) ref->release (ref->data); - /* set return value to 0 to inform the caller correctly */ - cnt = 0; - } - - return cnt; } #else -unsigned int +void * _gf_ref_get (gf_ref_t *ref) { unsigned int cnt = 0; @@ -69,10 +64,10 @@ _gf_ref_get (gf_ref_t *ref) } UNLOCK (&ref->lk); - return cnt; + return cnt ? ref->data : NULL; } -unsigned int +void _gf_ref_put (gf_ref_t *ref) { unsigned int cnt = 0; @@ -91,8 +86,6 @@ _gf_ref_put (gf_ref_t *ref) if (release && ref->release) ref->release (ref->data); - - return cnt; } #endif /* REFCOUNT_NEEDS_LOCK */ diff --git a/libglusterfs/src/refcount.h b/libglusterfs/src/refcount.h index e850e63..db9432a 100644 --- a/libglusterfs/src/refcount.h +++ b/libglusterfs/src/refcount.h @@ -42,7 +42,7 @@ typedef struct _gf_ref_t gf_ref_t; * * @return: greater then 0 when a reference was taken, 0 when not */ -unsigned int +void * _gf_ref_get (gf_ref_t *ref); /* _gf_ref_put -- decrease the refcount @@ -50,7 +50,7 @@ _gf_ref_get (gf_ref_t *ref); * @return: greater then 0 when there are still references, 0 when cleanup * should be done, gf_ref_release_t is called on cleanup */ -unsigned int +void _gf_ref_put (gf_ref_t *ref); /* _gf_ref_init -- initalize an embedded refcount object @@ -84,20 +84,20 @@ _gf_ref_init (gf_ref_t *ref, gf_ref_release_t release, void *data); * * Sets the refcount to 1. */ -#define GF_REF_INIT(p, d) _gf_ref_init (&p->_ref, d, p) +#define GF_REF_INIT(p, d) _gf_ref_init (&(p)->_ref, d, p) /* GF_REF_GET -- increase the refcount of a GF_REF_DECL structure * * @return: greater then 0 when a reference was taken, 0 when not */ -#define GF_REF_GET(p) _gf_ref_get (&p->_ref) +#define GF_REF_GET(p) _gf_ref_get (&(p)->_ref) /* GF_REF_PUT -- decrease the refcount of a GF_REF_DECL structure * * @return: greater then 0 when there are still references, 0 when cleanup * should be done, gf_ref_release_t is called on cleanup */ -#define GF_REF_PUT(p) _gf_ref_put (&p->_ref) +#define GF_REF_PUT(p) _gf_ref_put (&(p)->_ref) #endif /* _REFCOUNT_H */ diff --git a/xlators/nfs/server/src/auth-cache.c b/xlators/nfs/server/src/auth-cache.c index 730e0a9..a901e80 100644 --- a/xlators/nfs/server/src/auth-cache.c +++ b/xlators/nfs/server/src/auth-cache.c @@ -145,8 +145,9 @@ auth_cache_add (struct auth_cache *cache, char *hashkey, GF_VALIDATE_OR_GOTO (GF_NFS, cache, out); GF_VALIDATE_OR_GOTO (GF_NFS, cache->cache_dict, out); - ret = GF_REF_GET (entry); - if (ret == 0) { + /* FIXME: entry is passed as parameter, this can never fail? */ + entry = GF_REF_GET (entry); + if (!entry) { /* entry does not have any references */ ret = -1; goto out; @@ -221,8 +222,9 @@ auth_cache_get (struct auth_cache *cache, char *hashkey, if (!entry_data) goto unlock; - lookup_res = (struct auth_cache_entry *)(entry_data->data); - if (GF_REF_GET (lookup_res) == 0) { + /* FIXME: this is dangerous use of entry_data */ + lookup_res = GF_REF_GET ((struct auth_cache_entry *) entry_data->data); + if (lookup_res == NULL) { /* entry has been free'd */ ret = ENTRY_EXPIRED; goto unlock; -- 1.8.3.1