From 9f62e96084cd7ae6dedcfb4caf066ed6cc67e0d7 Mon Sep 17 00:00:00 2001 From: Sunil Mushran Date: Thu, 19 May 2011 14:34:09 -0700 Subject: ocfs2/dlm: dlm_is_lockres_migrateable() returns boolean Patch cleans up the gunk added by commit 388c4bcb4e63e88fb1f312a2f5f9eb2623afcf5b. dlm_is_lockres_migrateable() now returns 1 if lockresource is deemed migrateable and 0 if not. Signed-off-by: Sunil Mushran Signed-off-by: Joel Becker --- fs/ocfs2/dlm/dlmcommon.h | 12 +++++ fs/ocfs2/dlm/dlmmaster.c | 135 ++++++++++++++++++----------------------------- 2 files changed, 63 insertions(+), 84 deletions(-) diff --git a/fs/ocfs2/dlm/dlmcommon.h b/fs/ocfs2/dlm/dlmcommon.h index 4bdf7baee344..1aac42a29745 100644 --- a/fs/ocfs2/dlm/dlmcommon.h +++ b/fs/ocfs2/dlm/dlmcommon.h @@ -401,6 +401,18 @@ static inline int dlm_lvb_is_empty(char *lvb) return 1; } +static inline char *dlm_list_in_text(enum dlm_lockres_list idx) +{ + if (idx == DLM_GRANTED_LIST) + return "granted"; + else if (idx == DLM_CONVERTING_LIST) + return "converting"; + else if (idx == DLM_BLOCKED_LIST) + return "blocked"; + else + return "unknown"; +} + static inline struct list_head * dlm_list_idx_to_ptr(struct dlm_lock_resource *res, enum dlm_lockres_list idx) { diff --git a/fs/ocfs2/dlm/dlmmaster.c b/fs/ocfs2/dlm/dlmmaster.c index 84d166328cf7..ec4994628948 100644 --- a/fs/ocfs2/dlm/dlmmaster.c +++ b/fs/ocfs2/dlm/dlmmaster.c @@ -2339,65 +2339,55 @@ static void dlm_deref_lockres_worker(struct dlm_work_item *item, void *data) dlm_lockres_put(res); } -/* Checks whether the lockres can be migrated. Returns 0 if yes, < 0 - * if not. If 0, numlocks is set to the number of locks in the lockres. +/* + * A migrateable resource is one that is : + * 1. locally mastered, and, + * 2. zero local locks, and, + * 3. one or more non-local locks, or, one or more references + * Returns 1 if yes, 0 if not. */ static int dlm_is_lockres_migrateable(struct dlm_ctxt *dlm, - struct dlm_lock_resource *res, - int *numlocks, - int *hasrefs) + struct dlm_lock_resource *res) { - int ret; - int i; - int count = 0; + enum dlm_lockres_list idx; + int nonlocal = 0, node_ref; struct list_head *queue; struct dlm_lock *lock; + u64 cookie; assert_spin_locked(&res->spinlock); - *numlocks = 0; - *hasrefs = 0; - - ret = -EINVAL; - if (res->owner == DLM_LOCK_RES_OWNER_UNKNOWN) { - mlog(0, "cannot migrate lockres with unknown owner!\n"); - goto leave; - } - - if (res->owner != dlm->node_num) { - mlog(0, "cannot migrate lockres this node doesn't own!\n"); - goto leave; - } + if (res->owner != dlm->node_num) + return 0; - ret = 0; - queue = &res->granted; - for (i = 0; i < 3; i++) { + for (idx = DLM_GRANTED_LIST; idx <= DLM_BLOCKED_LIST; idx++) { + queue = dlm_list_idx_to_ptr(res, idx); list_for_each_entry(lock, queue, list) { - ++count; - if (lock->ml.node == dlm->node_num) { - mlog(0, "found a lock owned by this node still " - "on the %s queue! will not migrate this " - "lockres\n", (i == 0 ? "granted" : - (i == 1 ? "converting" : - "blocked"))); - ret = -ENOTEMPTY; - goto leave; + if (lock->ml.node != dlm->node_num) { + nonlocal++; + continue; } + cookie = be64_to_cpu(lock->ml.cookie); + mlog(0, "%s: Not migrateable res %.*s, lock %u:%llu on " + "%s list\n", dlm->name, res->lockname.len, + res->lockname.name, + dlm_get_lock_cookie_node(cookie), + dlm_get_lock_cookie_seq(cookie), + dlm_list_in_text(idx)); + return 0; } - queue++; } - *numlocks = count; - - count = find_next_bit(res->refmap, O2NM_MAX_NODES, 0); - if (count < O2NM_MAX_NODES) - *hasrefs = 1; + if (!nonlocal) { + node_ref = find_next_bit(res->refmap, O2NM_MAX_NODES, 0); + if (node_ref >= O2NM_MAX_NODES) + return 0; + } - mlog(0, "%s: res %.*s, Migrateable, locks %d, refs %d\n", dlm->name, - res->lockname.len, res->lockname.name, *numlocks, *hasrefs); + mlog(0, "%s: res %.*s, Migrateable\n", dlm->name, res->lockname.len, + res->lockname.name); -leave: - return ret; + return 1; } /* @@ -2416,7 +2406,6 @@ static int dlm_migrate_lockres(struct dlm_ctxt *dlm, const char *name; unsigned int namelen; int mle_added = 0; - int numlocks, hasrefs; int wake = 0; if (!dlm_grab(dlm)) @@ -2427,19 +2416,13 @@ static int dlm_migrate_lockres(struct dlm_ctxt *dlm, mlog(0, "%s: Migrating %.*s to %u\n", dlm->name, namelen, name, target); - /* - * ensure this lockres is a proper candidate for migration - */ + /* Ensure this lockres is a proper candidate for migration */ spin_lock(&res->spinlock); - ret = dlm_is_lockres_migrateable(dlm, res, &numlocks, &hasrefs); - if (ret < 0) { - spin_unlock(&res->spinlock); - goto leave; - } + ret = dlm_is_lockres_migrateable(dlm, res); spin_unlock(&res->spinlock); - /* no work to do */ - if (numlocks == 0 && !hasrefs) + /* No work to do */ + if (!ret) goto leave; /* @@ -2658,44 +2641,35 @@ leave: dlm_put(dlm); - mlog(0, "returning %d\n", ret); + mlog(0, "%s: Migrating %.*s to %u, returns %d\n", dlm->name, namelen, + name, target, ret); return ret; } #define DLM_MIGRATION_RETRY_MS 100 -/* Should be called only after beginning the domain leave process. +/* + * Should be called only after beginning the domain leave process. * There should not be any remaining locks on nonlocal lock resources, * and there should be no local locks left on locally mastered resources. * * Called with the dlm spinlock held, may drop it to do migration, but * will re-acquire before exit. * - * Returns: 1 if dlm->spinlock was dropped/retaken, 0 if never dropped */ + * Returns: 1 if dlm->spinlock was dropped/retaken, 0 if never dropped + */ int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) { - int ret; + int mig, ret; int lock_dropped = 0; - int numlocks, hasrefs; - spin_lock(&res->spinlock); - if (res->owner != dlm->node_num) { - if (!__dlm_lockres_unused(res)) { - mlog(ML_ERROR, "%s:%.*s: this node is not master, " - "trying to free this but locks remain\n", - dlm->name, res->lockname.len, res->lockname.name); - } - spin_unlock(&res->spinlock); - goto leave; - } + assert_spin_locked(&dlm->spinlock); - /* No need to migrate a lockres having no locks */ - ret = dlm_is_lockres_migrateable(dlm, res, &numlocks, &hasrefs); - if (ret >= 0 && numlocks == 0 && !hasrefs) { - spin_unlock(&res->spinlock); - goto leave; - } + spin_lock(&res->spinlock); + mig = dlm_is_lockres_migrateable(dlm, res); spin_unlock(&res->spinlock); + if (!mig) + goto leave; /* Wheee! Migrate lockres here! Will sleep so drop spinlock. */ spin_unlock(&dlm->spinlock); @@ -2704,15 +2678,8 @@ int dlm_empty_lockres(struct dlm_ctxt *dlm, struct dlm_lock_resource *res) ret = dlm_migrate_lockres(dlm, res, O2NM_MAX_NODES); if (ret >= 0) break; - if (ret == -ENOTEMPTY) { - mlog(ML_ERROR, "lockres %.*s still has local locks!\n", - res->lockname.len, res->lockname.name); - BUG(); - } - - mlog(0, "lockres %.*s: migrate failed, " - "retrying\n", res->lockname.len, - res->lockname.name); + mlog(0, "%s: res %.*s, Migrate failed, retrying\n", dlm->name, + res->lockname.len, res->lockname.name); msleep(DLM_MIGRATION_RETRY_MS); } spin_lock(&dlm->spinlock); -- cgit v1.2.3