All of lore.kernel.org
 help / color / mirror / Atom feed
From: Wei Yang <richard.weiyang@gmail.com>
To: tj@kernel.org, lizefan.x@bytedance.com, hannes@cmpxchg.org
Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
	Wei Yang <richard.weiyang@gmail.com>
Subject: [PATCH 3/4] cgroup: simplify the cgroup descendant helper
Date: Mon,  4 Oct 2021 08:49:27 +0000	[thread overview]
Message-ID: <20211004084928.17622-3-richard.weiyang@gmail.com> (raw)
In-Reply-To: <20211004084928.17622-1-richard.weiyang@gmail.com>

cgroup_for_each_live_descendant_[pre|post] use cgroup_css() to get the
root. While since the 2nd parameter is NULL, cgroup_css() always return
cgrp->self.

Let's simplify this a little.

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
---
 kernel/cgroup/cgroup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 570b0c97392a..457353aeb0ca 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -732,7 +732,7 @@ EXPORT_SYMBOL_GPL(of_css);
 
 /* walk live descendants in pre order */
 #define cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp)		\
-	css_for_each_descendant_pre((d_css), cgroup_css((cgrp), NULL))	\
+	css_for_each_descendant_pre((d_css), &(cgrp)->self)		\
 		if (({ lockdep_assert_held(&cgroup_mutex);		\
 		       (dsct) = (d_css)->cgroup;			\
 		       cgroup_is_dead(dsct); }))			\
@@ -741,7 +741,7 @@ EXPORT_SYMBOL_GPL(of_css);
 
 /* walk live descendants in postorder */
 #define cgroup_for_each_live_descendant_post(dsct, d_css, cgrp)		\
-	css_for_each_descendant_post((d_css), cgroup_css((cgrp), NULL))	\
+	css_for_each_descendant_post((d_css), &(cgrp)->self)		\
 		if (({ lockdep_assert_held(&cgroup_mutex);		\
 		       (dsct) = (d_css)->cgroup;			\
 		       cgroup_is_dead(dsct); }))			\
-- 
2.23.0


WARNING: multiple messages have this Message-ID (diff)
From: Wei Yang <richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org,
	lizefan.x-EC8Uxl6Npydl57MIdRCFDg@public.gmane.org,
	hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org
Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	Wei Yang
	<richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: [PATCH 3/4] cgroup: simplify the cgroup descendant helper
Date: Mon,  4 Oct 2021 08:49:27 +0000	[thread overview]
Message-ID: <20211004084928.17622-3-richard.weiyang@gmail.com> (raw)
In-Reply-To: <20211004084928.17622-1-richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

cgroup_for_each_live_descendant_[pre|post] use cgroup_css() to get the
root. While since the 2nd parameter is NULL, cgroup_css() always return
cgrp->self.

Let's simplify this a little.

Signed-off-by: Wei Yang <richard.weiyang-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
 kernel/cgroup/cgroup.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 570b0c97392a..457353aeb0ca 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -732,7 +732,7 @@ EXPORT_SYMBOL_GPL(of_css);
 
 /* walk live descendants in pre order */
 #define cgroup_for_each_live_descendant_pre(dsct, d_css, cgrp)		\
-	css_for_each_descendant_pre((d_css), cgroup_css((cgrp), NULL))	\
+	css_for_each_descendant_pre((d_css), &(cgrp)->self)		\
 		if (({ lockdep_assert_held(&cgroup_mutex);		\
 		       (dsct) = (d_css)->cgroup;			\
 		       cgroup_is_dead(dsct); }))			\
@@ -741,7 +741,7 @@ EXPORT_SYMBOL_GPL(of_css);
 
 /* walk live descendants in postorder */
 #define cgroup_for_each_live_descendant_post(dsct, d_css, cgrp)		\
-	css_for_each_descendant_post((d_css), cgroup_css((cgrp), NULL))	\
+	css_for_each_descendant_post((d_css), &(cgrp)->self)		\
 		if (({ lockdep_assert_held(&cgroup_mutex);		\
 		       (dsct) = (d_css)->cgroup;			\
 		       cgroup_is_dead(dsct); }))			\
-- 
2.23.0


  parent reply	other threads:[~2021-10-04  8:49 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-04  8:49 [PATCH 1/4] cgroup: a u16 is enough for cgroup_subsys.depends_on Wei Yang
2021-10-04  8:49 ` Wei Yang
2021-10-04  8:49 ` [PATCH 2/4] cgroup: reorder cgroup_subsys fields to save 8 byte Wei Yang
2021-10-04  8:49   ` Wei Yang
2021-10-04  8:49 ` Wei Yang [this message]
2021-10-04  8:49   ` [PATCH 3/4] cgroup: simplify the cgroup descendant helper Wei Yang
2021-10-04  8:49 ` [PATCH 4/4] cgroup: use parent directly instead of cgroup_parent() Wei Yang
2021-10-04  8:49   ` Wei Yang
2021-10-04 16:30 ` [PATCH 1/4] cgroup: a u16 is enough for cgroup_subsys.depends_on Tejun Heo
2021-10-04 16:30   ` Tejun Heo

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211004084928.17622-3-richard.weiyang@gmail.com \
    --to=richard.weiyang@gmail.com \
    --cc=cgroups@vger.kernel.org \
    --cc=hannes@cmpxchg.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lizefan.x@bytedance.com \
    --cc=tj@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.