From 7bf78408ffec1efbceed17ed2e540d7d0af19763 Mon Sep 17 00:00:00 2001 From: Anand Avati Date: Fri, 16 Oct 2009 09:12:57 +0000 Subject: locks: keep ref on the inode while locks are held keeping refs on the inode while there are held locks prevents the inode from getting pruned away Signed-off-by: Anand V. Avati BUG: 315 (generation number support) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=315 --- xlators/features/locks/src/common.c | 53 +++++++++++++++++++++++++++++++++++- xlators/features/locks/src/common.h | 2 ++ xlators/features/locks/src/entrylk.c | 1 + xlators/features/locks/src/inodelk.c | 1 + xlators/features/locks/src/locks.h | 15 ++++++---- xlators/features/locks/src/posix.c | 1 + 6 files changed, 66 insertions(+), 7 deletions(-) (limited to 'xlators') diff --git a/xlators/features/locks/src/common.c b/xlators/features/locks/src/common.c index 08dc451e1..b9037688a 100644 --- a/xlators/features/locks/src/common.c +++ b/xlators/features/locks/src/common.c @@ -35,6 +35,7 @@ #include "common-utils.h" #include "locks.h" +#include "common.h" static int @@ -43,7 +44,7 @@ static void __insert_and_merge (pl_inode_t *pl_inode, posix_lock_t *lock); static pl_dom_list_t * -allocate_domain(const char *volume) +allocate_domain (const char *volume) { pl_dom_list_t *dom = NULL; @@ -95,6 +96,56 @@ found: return dom; } + +int +__pl_inode_is_empty (pl_inode_t *pl_inode) +{ + pl_dom_list_t *dom = NULL; + int is_empty = 1; + + if (!list_empty (&pl_inode->ext_list)) + is_empty = 0; + + list_for_each_entry (dom, &pl_inode->dom_list, inode_list) { + if (!list_empty (&dom->entrylk_list)) + is_empty = 0; + + if (!list_empty (&dom->inodelk_list)) + is_empty = 0; + } + + return is_empty; +} + +void +pl_update_refkeeper (xlator_t *this, inode_t *inode) +{ + pl_inode_t *pl_inode = NULL; + int is_empty = 0; + int need_unref = 0; + + pl_inode = pl_inode_get (this, inode); + + pthread_mutex_lock (&pl_inode->mutex); + { + is_empty = __pl_inode_is_empty (pl_inode); + + if (is_empty && pl_inode->refkeeper) { + need_unref = 1; + pl_inode->refkeeper = NULL; + } + + if (!is_empty && !pl_inode->refkeeper) { + pl_inode->refkeeper = inode_ref (inode); + } + } + pthread_mutex_unlock (&pl_inode->mutex); + + if (need_unref) + inode_unref (inode); +} + + pl_inode_t * pl_inode_get (xlator_t *this, inode_t *inode) { diff --git a/xlators/features/locks/src/common.h b/xlators/features/locks/src/common.h index fabe8bd84..59201c907 100644 --- a/xlators/features/locks/src/common.h +++ b/xlators/features/locks/src/common.h @@ -65,4 +65,6 @@ void grant_blocked_entry_locks (xlator_t *this, pl_inode_t *pl_inode, pl_entry_lock_t *unlocked, pl_dom_list_t *dom); +void pl_update_refkeeper (xlator_t *this, inode_t *inode); + #endif /* __COMMON_H__ */ diff --git a/xlators/features/locks/src/entrylk.c b/xlators/features/locks/src/entrylk.c index f1536f803..e22a8305d 100644 --- a/xlators/features/locks/src/entrylk.c +++ b/xlators/features/locks/src/entrylk.c @@ -534,6 +534,7 @@ pl_common_entrylk (call_frame_t *frame, xlator_t *this, op_ret = 0; out: + pl_update_refkeeper (this, inode); if (unwind) { STACK_UNWIND_STRICT (entrylk, frame, op_ret, op_errno); } diff --git a/xlators/features/locks/src/inodelk.c b/xlators/features/locks/src/inodelk.c index 4c76f64bb..1cb2c9522 100644 --- a/xlators/features/locks/src/inodelk.c +++ b/xlators/features/locks/src/inodelk.c @@ -525,6 +525,7 @@ pl_common_inodelk (call_frame_t *frame, xlator_t *this, op_ret = 0; unwind: + pl_update_refkeeper (this, inode); STACK_UNWIND_STRICT (inodelk, frame, op_ret, op_errno); out: return 0; diff --git a/xlators/features/locks/src/locks.h b/xlators/features/locks/src/locks.h index 4ad16c714..9d030f15e 100644 --- a/xlators/features/locks/src/locks.h +++ b/xlators/features/locks/src/locks.h @@ -86,12 +86,12 @@ struct __pl_rw_req_t { typedef struct __pl_rw_req_t pl_rw_req_t; struct __pl_dom_list_t { - const char *domain; - struct list_head inode_list; /* list_head back to pl_inode_t */ - struct list_head entrylk_list; /* List of entry locks */ - struct list_head blocked_entrylks; /* List of all blocked entrylks */ - struct list_head inodelk_list; /* List of inode locks */ - struct list_head blocked_inodelks; /* List of all blocked inodelks */ + struct list_head inode_list; /* list_head back to pl_inode_t */ + const char *domain; + struct list_head entrylk_list; /* List of entry locks */ + struct list_head blocked_entrylks; /* List of all blocked entrylks */ + struct list_head inodelk_list; /* List of inode locks */ + struct list_head blocked_inodelks; /* List of all blocked inodelks */ }; typedef struct __pl_dom_list_t pl_dom_list_t; @@ -123,6 +123,9 @@ struct __pl_inode { struct list_head ext_list; /* list of fcntl locks */ struct list_head rw_list; /* list of waiting r/w requests */ int mandatory; /* if mandatory locking is enabled */ + + inode_t *refkeeper; /* hold refs on an inode while locks are + held to prevent pruning */ }; typedef struct __pl_inode pl_inode_t; diff --git a/xlators/features/locks/src/posix.c b/xlators/features/locks/src/posix.c index f2e73b9cb..50958a2ed 100644 --- a/xlators/features/locks/src/posix.c +++ b/xlators/features/locks/src/posix.c @@ -686,6 +686,7 @@ pl_lk (call_frame_t *frame, xlator_t *this, } unwind: + pl_update_refkeeper (this, fd->inode); STACK_UNWIND_STRICT (lk, frame, op_ret, op_errno, flock); out: return 0; -- cgit