Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932234Ab3FLVFp (ORCPT ); Wed, 12 Jun 2013 17:05:45 -0400 Received: from mail-yh0-f52.google.com ([209.85.213.52]:49959 "EHLO mail-yh0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758074Ab3FLVDl (ORCPT ); Wed, 12 Jun 2013 17:03:41 -0400 From: Tejun Heo To: lizefan@huawei.com Cc: containers@lists.linux-foundation.org, cgroups@vger.kernel.org, koverstreet@google.com, linux-kernel@vger.kernel.org, cl@linux-foundation.org, Tejun Heo Subject: [PATCH 05/11] cgroup: clean up css_[try]get() and css_put() Date: Wed, 12 Jun 2013 14:03:10 -0700 Message-Id: <1371070996-20613-6-git-send-email-tj@kernel.org> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1371070996-20613-1-git-send-email-tj@kernel.org> References: <1371070996-20613-1-git-send-email-tj@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2826 Lines: 94 * __css_get() isn't used by anyone. Fold it into css_get(). * Add proper function comments to all css reference functions. This patch is purely cosmetic. Signed-off-by: Tejun Heo --- include/linux/cgroup.h | 48 ++++++++++++++++++++++++------------------------ 1 file changed, 24 insertions(+), 24 deletions(-) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 0e32855..7b16882 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -94,33 +94,31 @@ enum { CSS_ONLINE = (1 << 1), /* between ->css_online() and ->css_offline() */ }; -/* Caller must verify that the css is not for root cgroup */ -static inline void __css_get(struct cgroup_subsys_state *css, int count) -{ - atomic_add(count, &css->refcnt); -} - -/* - * Call css_get() to hold a reference on the css; it can be used - * for a reference obtained via: - * - an existing ref-counted reference to the css - * - task->cgroups for a locked task +/** + * css_get - obtain a reference on the specified css + * @css: taget css + * + * The caller must already have a reference. */ - static inline void css_get(struct cgroup_subsys_state *css) { /* We don't need to reference count the root state */ if (!(css->flags & CSS_ROOT)) - __css_get(css, 1); + atomic_inc(&css->refcnt); } -/* - * Call css_tryget() to take a reference on a css if your existing - * (known-valid) reference isn't already ref-counted. Returns false if - * the css has been destroyed. - */ - extern bool __css_tryget(struct cgroup_subsys_state *css); + +/** + * css_tryget - try to obtain a reference on the specified css + * @css: target css + * + * Obtain a reference on @css if it's alive. The caller naturally needs to + * ensure that @css is accessible but doesn't have to be holding a + * reference on it - IOW, RCU protected access is good enough for this + * function. Returns %true if a reference count was successfully obtained; + * %false otherwise. + */ static inline bool css_tryget(struct cgroup_subsys_state *css) { if (css->flags & CSS_ROOT) @@ -128,12 +126,14 @@ static inline bool css_tryget(struct cgroup_subsys_state *css) return __css_tryget(css); } -/* - * css_put() should be called to release a reference taken by - * css_get() or css_tryget() - */ - extern void __css_put(struct cgroup_subsys_state *css); + +/** + * css_put - put a css reference + * @css: target css + * + * Put a reference obtained via css_get() and css_tryget(). + */ static inline void css_put(struct cgroup_subsys_state *css) { if (!(css->flags & CSS_ROOT)) -- 1.8.2.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/