From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Simmons Date: Thu, 27 Feb 2020 16:17:49 -0500 Subject: [lustre-devel] [PATCH 601/622] lustre: handle: use hlist for hash lists. In-Reply-To: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> References: <1582838290-17243-1-git-send-email-jsimmons@infradead.org> Message-ID: <1582838290-17243-602-git-send-email-jsimmons@infradead.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: lustre-devel@lists.lustre.org From: NeilBrown hlist_head/hlist_node is the preferred data structure for hash tables. Not only does it make the 'head' smaller, but is also provides hlist_unhashed() which can be used to check if an object is in the list. This means that we don't need h_in any more. WC-bug-id: https://jira.whamcloud.com/browse/LU-12542 Lustre-commit: 9c9ea6584cfb ("LU-12542 handle: use hlist for hash lists.") Signed-off-by: NeilBrown Reviewed-on: https://review.whamcloud.com/35862 Reviewed-by: Neil Brown Reviewed-by: Shaun Tancheff Reviewed-by: Yang Sheng Reviewed-by: Oleg Drokin Signed-off-by: James Simmons --- fs/lustre/include/lustre_handles.h | 3 +-- fs/lustre/ldlm/ldlm_lock.c | 2 +- fs/lustre/obdclass/genops.c | 2 +- fs/lustre/obdclass/lustre_handles.c | 20 +++++++++----------- 4 files changed, 12 insertions(+), 15 deletions(-) diff --git a/fs/lustre/include/lustre_handles.h b/fs/lustre/include/lustre_handles.h index 55f9a09..afdade7 100644 --- a/fs/lustre/include/lustre_handles.h +++ b/fs/lustre/include/lustre_handles.h @@ -58,7 +58,7 @@ * to compute the start of the structure based on the handle field. */ struct portals_handle { - struct list_head h_link; + struct hlist_node h_link; u64 h_cookie; const char *h_owner; refcount_t h_ref; @@ -66,7 +66,6 @@ struct portals_handle { /* newly added fields to handle the RCU issue. -jxiong */ struct rcu_head h_rcu; spinlock_t h_lock; - unsigned int h_in:1; }; /* handles.c */ diff --git a/fs/lustre/ldlm/ldlm_lock.c b/fs/lustre/ldlm/ldlm_lock.c index 2c19636..396bf53 100644 --- a/fs/lustre/ldlm/ldlm_lock.c +++ b/fs/lustre/ldlm/ldlm_lock.c @@ -404,7 +404,7 @@ static struct ldlm_lock *ldlm_lock_new(struct ldlm_resource *resource) lprocfs_counter_incr(ldlm_res_to_ns(resource)->ns_stats, LDLM_NSS_LOCKS); - INIT_LIST_HEAD(&lock->l_handle.h_link); + INIT_HLIST_NODE(&lock->l_handle.h_link); class_handle_hash(&lock->l_handle, lock_handle_owner); lu_ref_init(&lock->l_reference); diff --git a/fs/lustre/obdclass/genops.c b/fs/lustre/obdclass/genops.c index 0fbe03e..146e735 100644 --- a/fs/lustre/obdclass/genops.c +++ b/fs/lustre/obdclass/genops.c @@ -813,7 +813,7 @@ static struct obd_export *__class_new_export(struct obd_device *obd, spin_lock_init(&export->exp_uncommitted_replies_lock); INIT_LIST_HEAD(&export->exp_uncommitted_replies); INIT_LIST_HEAD(&export->exp_req_replay_queue); - INIT_LIST_HEAD_RCU(&export->exp_handle.h_link); + INIT_HLIST_NODE(&export->exp_handle.h_link); INIT_LIST_HEAD(&export->exp_hp_rpcs); class_handle_hash(&export->exp_handle, export_handle_owner); spin_lock_init(&export->exp_lock); diff --git a/fs/lustre/obdclass/lustre_handles.c b/fs/lustre/obdclass/lustre_handles.c index acee2db..0048036 100644 --- a/fs/lustre/obdclass/lustre_handles.c +++ b/fs/lustre/obdclass/lustre_handles.c @@ -48,7 +48,7 @@ static struct handle_bucket { spinlock_t lock; - struct list_head head; + struct hlist_head head; } *handle_hash; #define HANDLE_HASH_SIZE (1 << 16) @@ -63,7 +63,7 @@ void class_handle_hash(struct portals_handle *h, const char *owner) struct handle_bucket *bucket; LASSERT(h); - LASSERT(list_empty(&h->h_link)); + LASSERT(hlist_unhashed(&h->h_link)); /* * This is fast, but simplistic cookie generation algorithm, it will @@ -89,8 +89,7 @@ void class_handle_hash(struct portals_handle *h, const char *owner) bucket = &handle_hash[h->h_cookie & HANDLE_HASH_MASK]; spin_lock(&bucket->lock); - list_add_rcu(&h->h_link, &bucket->head); - h->h_in = 1; + hlist_add_head_rcu(&h->h_link, &bucket->head); spin_unlock(&bucket->lock); CDEBUG(D_INFO, "added object %p with handle %#llx to hash\n", @@ -100,7 +99,7 @@ void class_handle_hash(struct portals_handle *h, const char *owner) static void class_handle_unhash_nolock(struct portals_handle *h) { - if (list_empty(&h->h_link)) { + if (hlist_unhashed(&h->h_link)) { CERROR("removing an already-removed handle (%#llx)\n", h->h_cookie); return; @@ -110,13 +109,12 @@ static void class_handle_unhash_nolock(struct portals_handle *h) h, h->h_cookie); spin_lock(&h->h_lock); - if (h->h_in == 0) { + if (hlist_unhashed(&h->h_link)) { spin_unlock(&h->h_lock); return; } - h->h_in = 0; + hlist_del_init_rcu(&h->h_link); spin_unlock(&h->h_lock); - list_del_rcu(&h->h_link); } void class_handle_unhash(struct portals_handle *h) @@ -145,7 +143,7 @@ void *class_handle2object(u64 cookie, const char *owner) bucket = handle_hash + (cookie & HANDLE_HASH_MASK); rcu_read_lock(); - list_for_each_entry_rcu(h, &bucket->head, h_link) { + hlist_for_each_entry_rcu(h, &bucket->head, h_link) { if (h->h_cookie != cookie || h->h_owner != owner) continue; @@ -177,7 +175,7 @@ int class_handle_init(void) spin_lock_init(&handle_base_lock); for (bucket = handle_hash + HANDLE_HASH_SIZE - 1; bucket >= handle_hash; bucket--) { - INIT_LIST_HEAD(&bucket->head); + INIT_HLIST_HEAD(&bucket->head); spin_lock_init(&bucket->lock); } @@ -196,7 +194,7 @@ static int cleanup_all_handles(void) struct portals_handle *h; spin_lock(&handle_hash[i].lock); - list_for_each_entry_rcu(h, &handle_hash[i].head, h_link) { + hlist_for_each_entry_rcu(h, &handle_hash[i].head, h_link) { CERROR("force clean handle %#llx addr %p owner %p\n", h->h_cookie, h, h->h_owner); -- 1.8.3.1