From 6246dab1d0d3a91614eb0360e51d9e98b919dbb1 Mon Sep 17 00:00:00 2001 From: Dmitry Eremin Date: Sun, 27 Apr 2014 13:06:59 -0400 Subject: [PATCH] staging/lustre: replace semaphores with mutexes It's just optimization. The mutex subsystem is slightly faster and has better scalability for contended workloads. Remove the lustre_lock and it's accessor functions l_lock(), l_unlock(), l_lock_init(), and l_has_lock() since they have not been used by the code since Lustre 1.6. Signed-off-by: Dmitry Eremin Reviewed-on: http://review.whamcloud.com/9294 Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4588 Reviewed-by: Andreas Dilger Reviewed-by: John L. Hammond Reviewed-by: James Simmons Reviewed-by: Alex Zhuravlev Signed-off-by: Oleg Drokin Signed-off-by: Greg Kroah-Hartman --- .../staging/lustre/lustre/include/lustre_lib.h | 13 ------------- drivers/staging/lustre/lustre/include/obd.h | 2 +- drivers/staging/lustre/lustre/ldlm/ldlm_lib.c | 2 +- .../lustre/lustre/libcfs/linux/linux-cpu.c | 16 ++++++++-------- drivers/staging/lustre/lustre/mgc/mgc_request.c | 8 ++++---- 5 files changed, 14 insertions(+), 27 deletions(-) diff --git a/drivers/staging/lustre/lustre/include/lustre_lib.h b/drivers/staging/lustre/lustre/include/lustre_lib.h index 0368ca6ffcc1..bdc981214805 100644 --- a/drivers/staging/lustre/lustre/include/lustre_lib.h +++ b/drivers/staging/lustre/lustre/include/lustre_lib.h @@ -94,19 +94,6 @@ struct obd_client_handle { void statfs_pack(struct obd_statfs *osfs, struct kstatfs *sfs); void statfs_unpack(struct kstatfs *sfs, struct obd_statfs *osfs); -/* l_lock.c */ -struct lustre_lock { - int l_depth; - struct task_struct *l_owner; - struct semaphore l_sem; - spinlock_t l_spin; -}; - -void l_lock_init(struct lustre_lock *); -void l_lock(struct lustre_lock *); -void l_unlock(struct lustre_lock *); -int l_has_lock(struct lustre_lock *); - /* * For md echo client */ diff --git a/drivers/staging/lustre/lustre/include/obd.h b/drivers/staging/lustre/lustre/include/obd.h index 7ed5fcd7f86d..d5c4613f182d 100644 --- a/drivers/staging/lustre/lustre/include/obd.h +++ b/drivers/staging/lustre/lustre/include/obd.h @@ -406,7 +406,7 @@ struct client_obd { struct mdc_rpc_lock *cl_close_lock; /* mgc datastruct */ - struct semaphore cl_mgc_sem; + struct mutex cl_mgc_mutex; struct local_oid_storage *cl_mgc_los; struct dt_object *cl_mgc_configs_dir; atomic_t cl_mgc_refcount; diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_lib.c b/drivers/staging/lustre/lustre/ldlm/ldlm_lib.c index 42f5f1e54fcc..8bb59155968f 100644 --- a/drivers/staging/lustre/lustre/ldlm/ldlm_lib.c +++ b/drivers/staging/lustre/lustre/ldlm/ldlm_lib.c @@ -325,7 +325,7 @@ int client_obd_setup(struct obd_device *obddev, struct lustre_cfg *lcfg) } init_rwsem(&cli->cl_sem); - sema_init(&cli->cl_mgc_sem, 1); + mutex_init(&cli->cl_mgc_mutex); cli->cl_conn_count = 0; memcpy(server_uuid.uuid, lustre_cfg_buf(lcfg, 2), min_t(unsigned int, LUSTRE_CFG_BUFLEN(lcfg, 2), diff --git a/drivers/staging/lustre/lustre/libcfs/linux/linux-cpu.c b/drivers/staging/lustre/lustre/libcfs/linux/linux-cpu.c index d169374eb98d..fc21210d77ec 100644 --- a/drivers/staging/lustre/lustre/libcfs/linux/linux-cpu.c +++ b/drivers/staging/lustre/lustre/libcfs/linux/linux-cpu.c @@ -71,7 +71,7 @@ struct cfs_cpt_data { /* reserved for hotplug */ unsigned long cpt_version; /* mutex to protect cpt_cpumask */ - struct semaphore cpt_mutex; + struct mutex cpt_mutex; /* scratch buffer for set/unset_node */ cpumask_t *cpt_cpumask; }; @@ -420,14 +420,14 @@ cfs_cpt_set_node(struct cfs_cpt_table *cptab, int cpt, int node) return 0; } - down(&cpt_data.cpt_mutex); + mutex_lock(&cpt_data.cpt_mutex); mask = cpt_data.cpt_cpumask; cfs_node_to_cpumask(node, mask); rc = cfs_cpt_set_cpumask(cptab, cpt, mask); - up(&cpt_data.cpt_mutex); + mutex_unlock(&cpt_data.cpt_mutex); return rc; } @@ -444,14 +444,14 @@ cfs_cpt_unset_node(struct cfs_cpt_table *cptab, int cpt, int node) return; } - down(&cpt_data.cpt_mutex); + mutex_lock(&cpt_data.cpt_mutex); mask = cpt_data.cpt_cpumask; cfs_node_to_cpumask(node, mask); cfs_cpt_unset_cpumask(cptab, cpt, mask); - up(&cpt_data.cpt_mutex); + mutex_unlock(&cpt_data.cpt_mutex); } EXPORT_SYMBOL(cfs_cpt_unset_node); @@ -969,11 +969,11 @@ cfs_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) break; } - down(&cpt_data.cpt_mutex); + mutex_lock(&cpt_data.cpt_mutex); /* if all HTs in a core are offline, it may break affinity */ cfs_cpu_ht_siblings(cpu, cpt_data.cpt_cpumask); warn = any_online_cpu(*cpt_data.cpt_cpumask) >= nr_cpu_ids; - up(&cpt_data.cpt_mutex); + mutex_unlock(&cpt_data.cpt_mutex); CDEBUG(warn ? D_WARNING : D_INFO, "Lustre: can't support CPU plug-out well now, " "performance and stability could be impacted " @@ -1017,7 +1017,7 @@ cfs_cpu_init(void) } spin_lock_init(&cpt_data.cpt_lock); - sema_init(&cpt_data.cpt_mutex, 1); + mutex_init(&cpt_data.cpt_mutex); #ifdef CONFIG_HOTPLUG_CPU register_hotcpu_notifier(&cfs_cpu_notifier); diff --git a/drivers/staging/lustre/lustre/mgc/mgc_request.c b/drivers/staging/lustre/lustre/mgc/mgc_request.c index de9fb1433edd..a806aeffe026 100644 --- a/drivers/staging/lustre/lustre/mgc/mgc_request.c +++ b/drivers/staging/lustre/lustre/mgc/mgc_request.c @@ -672,8 +672,8 @@ static int mgc_fs_setup(struct obd_device *obd, struct super_block *sb) if (env == NULL) return -ENOMEM; - /* The mgc fs exclusion sem. Only one fs can be setup at a time. */ - down(&cli->cl_mgc_sem); + /* The mgc fs exclusion mutex. Only one fs can be setup at a time. */ + mutex_lock(&cli->cl_mgc_mutex); cfs_cleanup_group_info(); @@ -727,7 +727,7 @@ out_los: if (rc < 0) { local_oid_storage_fini(env, cli->cl_mgc_los); cli->cl_mgc_los = NULL; - up(&cli->cl_mgc_sem); + mutex_unlock(&cli->cl_mgc_mutex); } out_env: lu_env_fini(env); @@ -759,7 +759,7 @@ static int mgc_fs_cleanup(struct obd_device *obd) unlock: class_decref(obd, "mgc_fs", obd); - up(&cli->cl_mgc_sem); + mutex_unlock(&cli->cl_mgc_mutex); return 0; } -- 2.20.1