From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH v7 02/16] userns: use new hashtable implementation Date: Sun, 28 Oct 2012 15:02:14 -0400 Message-ID: <1351450948-15618-2-git-send-email-levinsasha928@gmail.com> References: <1351450948-15618-1-git-send-email-levinsasha928@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: snitzer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, neilb-l3A5Bk7waGM@public.gmane.org, fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Trond.Myklebust-HgOvQuBEEgTQT0dZR+AlfA@public.gmane.org, bfields-uC3wQj2KruNg9hUCZPvPmw@public.gmane.org, paul.gortmaker-CWA4WttNNZF54TAoqtyWWQ@public.gmane.org, dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, agk-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, aarcange-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, rds-devel-N0ozoZBvEnrZJqsBc5GL+g@public.gmane.org, eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, venkat.x.venkatsubra-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, ccaulfie-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, mingo-X9Un+BFzKDI@public.gmane.org, dev-yBygre7rU0TnMu66kgdUjQ@public.gmane.org, ericvh-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, josh-iaAMLnmF4UmaiuxdJuQwMA@public.gmane.org, rostedt-nx8X9YLhiw1AfugRpC6u6w@public.gmane.org, lw-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org, mathieu.desnoyers-vg+e7yoeK/dWk0Htik3J/w@public.gmane.org, Sasha Levin , axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, edumazet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, ejt-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, teigland-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org To: torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org Return-path: In-Reply-To: <1351450948-15618-1-git-send-email-levinsasha928-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dev-bounces-yBygre7rU0TnMu66kgdUjQ@public.gmane.org Errors-To: dev-bounces-yBygre7rU0TnMu66kgdUjQ@public.gmane.org List-Id: netdev.vger.kernel.org Switch to using the new hashtable implementation to store user structs. This reduces the amount of generic unrelated code in kernel/user.c. Signed-off-by: Sasha Levin --- kernel/user.c | 33 +++++++++++++-------------------- 1 file changed, 13 insertions(+), 20 deletions(-) diff --git a/kernel/user.c b/kernel/user.c index 750acff..8cd922a 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -16,6 +16,7 @@ #include #include #include +#include /* * userns count is 1 for root user, 1 for init_uts_ns, @@ -60,13 +61,9 @@ EXPORT_SYMBOL_GPL(init_user_ns); */ #define UIDHASH_BITS (CONFIG_BASE_SMALL ? 3 : 7) -#define UIDHASH_SZ (1 << UIDHASH_BITS) -#define UIDHASH_MASK (UIDHASH_SZ - 1) -#define __uidhashfn(uid) (((uid >> UIDHASH_BITS) + uid) & UIDHASH_MASK) -#define uidhashentry(uid) (uidhash_table + __uidhashfn((__kuid_val(uid)))) static struct kmem_cache *uid_cachep; -struct hlist_head uidhash_table[UIDHASH_SZ]; +static DEFINE_HASHTABLE(uidhash_table, UIDHASH_BITS); /* * The uidhash_lock is mostly taken from process context, but it is @@ -92,22 +89,22 @@ struct user_struct root_user = { /* * These routines must be called with the uidhash spinlock held! */ -static void uid_hash_insert(struct user_struct *up, struct hlist_head *hashent) +static void uid_hash_insert(struct user_struct *up) { - hlist_add_head(&up->uidhash_node, hashent); + hash_add(uidhash_table, &up->uidhash_node, __kuid_val(up->uid)); } static void uid_hash_remove(struct user_struct *up) { - hlist_del_init(&up->uidhash_node); + hash_del(&up->uidhash_node); } -static struct user_struct *uid_hash_find(kuid_t uid, struct hlist_head *hashent) +static struct user_struct *uid_hash_find(kuid_t uid) { struct user_struct *user; struct hlist_node *h; - hlist_for_each_entry(user, h, hashent, uidhash_node) { + hash_for_each_possible(uidhash_table, user, h, uidhash_node, __kuid_val(uid)) { if (uid_eq(user->uid, uid)) { atomic_inc(&user->__count); return user; @@ -143,7 +140,7 @@ struct user_struct *find_user(kuid_t uid) unsigned long flags; spin_lock_irqsave(&uidhash_lock, flags); - ret = uid_hash_find(uid, uidhashentry(uid)); + ret = uid_hash_find(uid); spin_unlock_irqrestore(&uidhash_lock, flags); return ret; } @@ -164,11 +161,10 @@ void free_uid(struct user_struct *up) struct user_struct *alloc_uid(kuid_t uid) { - struct hlist_head *hashent = uidhashentry(uid); struct user_struct *up, *new; spin_lock_irq(&uidhash_lock); - up = uid_hash_find(uid, hashent); + up = uid_hash_find(uid); spin_unlock_irq(&uidhash_lock); if (!up) { @@ -184,13 +180,13 @@ struct user_struct *alloc_uid(kuid_t uid) * on adding the same user already.. */ spin_lock_irq(&uidhash_lock); - up = uid_hash_find(uid, hashent); + up = uid_hash_find(uid); if (up) { key_put(new->uid_keyring); key_put(new->session_keyring); kmem_cache_free(uid_cachep, new); } else { - uid_hash_insert(new, hashent); + uid_hash_insert(new); up = new; } spin_unlock_irq(&uidhash_lock); @@ -204,17 +200,14 @@ out_unlock: static int __init uid_cache_init(void) { - int n; - uid_cachep = kmem_cache_create("uid_cache", sizeof(struct user_struct), 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL); - for(n = 0; n < UIDHASH_SZ; ++n) - INIT_HLIST_HEAD(uidhash_table + n); + hash_init(uidhash_table); /* Insert the root user immediately (init already runs as root) */ spin_lock_irq(&uidhash_lock); - uid_hash_insert(&root_user, uidhashentry(GLOBAL_ROOT_UID)); + uid_hash_insert(&root_user); spin_unlock_irq(&uidhash_lock); return 0; -- 1.7.12.4