diff options
author | Jeff Darcy <jdarcy@redhat.com> | 2014-04-28 14:18:50 +0000 |
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committer | Jeff Darcy <jdarcy@redhat.com> | 2014-04-28 14:18:50 +0000 |
commit | e139b4d0ba2286c0d4d44ba81260c2b287016019 (patch) | |
tree | 0a21f0761528e0f79da0a9f67106eb128ace0cf7 /xlators/features/locks/src/entrylk.c | |
parent | 73b60c87ca7f62517a8466431f5a8cf167589c8c (diff) | |
parent | f2bac9f9d5b9956969ddd25a54bc636b82f6923e (diff) |
Conflicts:
rpc/xdr/src/glusterfs3-xdr.c
rpc/xdr/src/glusterfs3-xdr.h
xlators/features/changelog/src/Makefile.am
xlators/features/changelog/src/changelog-helpers.h
xlators/features/changelog/src/changelog.c
xlators/mgmt/glusterd/src/glusterd-sm.c
Change-Id: I9972a5e6184503477eb77a8b56c50a4db4eec3e2
Diffstat (limited to 'xlators/features/locks/src/entrylk.c')
-rw-r--r-- | xlators/features/locks/src/entrylk.c | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/xlators/features/locks/src/entrylk.c b/xlators/features/locks/src/entrylk.c index dc86512be..8496d9d8d 100644 --- a/xlators/features/locks/src/entrylk.c +++ b/xlators/features/locks/src/entrylk.c @@ -715,15 +715,16 @@ pl_entrylk_client_cleanup (xlator_t *this, pl_ctx_t *ctx) pl_inode_t *pinode = NULL; struct list_head released; + struct list_head unwind; INIT_LIST_HEAD (&released); + INIT_LIST_HEAD (&unwind); pthread_mutex_lock (&ctx->lock); { list_for_each_entry_safe (l, tmp, &ctx->entrylk_lockers, client_list) { list_del_init (&l->client_list); - list_add_tail (&l->client_list, &released); pl_entrylk_log_cleanup (l); @@ -731,25 +732,68 @@ pl_entrylk_client_cleanup (xlator_t *this, pl_ctx_t *ctx) pthread_mutex_lock (&pinode->mutex); { - list_del_init (&l->domain_list); + /* If the entrylk object is part of granted list but not + * blocked list, then perform the following actions: + * i. delete the object from granted list; + * ii. grant other locks (from other clients) that may + * have been blocked on this entrylk; and + * iii. unref the object. + * + * If the entrylk object (L1) is part of both granted + * and blocked lists, then this means that a parallel + * unlock on another entrylk (L2 say) may have 'granted' + * L1 and added it to 'granted' list in + * __grant_blocked_entry_locks() (although using the + * 'blocked_locks' member). In that case, the cleanup + * codepath must try and grant other overlapping + * blocked entrylks from other clients, now that L1 is + * out of their way and then unref L1 in the end, and + * leave it to the other thread (the one executing + * unlock codepath) to unwind L1's frame, delete it from + * blocked_locks list, and perform the last unref on L1. + * + * If the entrylk object (L1) is part of blocked list + * only, the cleanup code path must: + * i. delete it from the blocked_locks list inside + * this critical section, + * ii. unwind its frame with EAGAIN, + * iii. try and grant blocked entry locks from other + * clients that were otherwise grantable, but were + * blocked to avoid leaving L1 to starve forever. + * iv. unref the object. + */ + if (!list_empty (&l->domain_list)) { + list_del_init (&l->domain_list); + list_add_tail (&l->client_list, + &released); + } else { + list_del_init (&l->blocked_locks); + list_add_tail (&l->client_list, + &unwind); + } } pthread_mutex_unlock (&pinode->mutex); } } pthread_mutex_unlock (&ctx->lock); - list_for_each_entry_safe (l, tmp, &released, client_list) { + list_for_each_entry_safe (l, tmp, &unwind, client_list) { list_del_init (&l->client_list); if (l->frame) STACK_UNWIND_STRICT (entrylk, l->frame, -1, EAGAIN, NULL); + list_add_tail (&l->client_list, &released); + } + + list_for_each_entry_safe (l, tmp, &released, client_list) { + list_del_init (&l->client_list); pinode = l->pinode; dom = get_domain (pinode, l->volume); - grant_blocked_inode_locks (this, pinode, dom); + grant_blocked_entry_locks (this, pinode, dom); pthread_mutex_lock (&pinode->mutex); { |