linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Davidlohr Bueso <dave@stgolabs.net>
To: Manfred Spraul <manfred@colorfullife.com>
Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	Davidlohr Bueso <dbueso@suse.de>
Subject: Re: [PATCH 1/5] ipc/sem: do not call wake_sem_queue_do() prematurely
Date: Tue, 13 Sep 2016 01:14:41 -0700	[thread overview]
Message-ID: <20160913081441.GA32365@linux-80c1.suse> (raw)
In-Reply-To: <c9039969-21f7-597d-0986-895c176901ad@colorfullife.com>

On Tue, 13 Sep 2016, Manfred Spraul wrote:

>>-	if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO))
>>-		goto out_rcu_wakeup;
>>+	if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO)) {
>>+		rcu_read_unlock();
>>+		goto out_free;
>>+	}
>Is this really better/simpler?
>You replace "if (error) goto cleanup" with "if (error) {cleanup_1(); 
>goto cleanup_2()}".

I believe it is better as it clearly separates blocking from non-blocking
exit paths. Overhead of course is irrelevant in both in-house wake_up_sem_queue_do
and wake_up_q.

Thanks,
Davidlohr

  reply	other threads:[~2016-09-13  8:14 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-09-12 11:53 [PATCH -next 0/5] ipc/sem: semop(2) improvements Davidlohr Bueso
2016-09-12 11:53 ` [PATCH 1/5] ipc/sem: do not call wake_sem_queue_do() prematurely Davidlohr Bueso
2016-09-13  4:17   ` Manfred Spraul
2016-09-13  8:14     ` Davidlohr Bueso [this message]
2016-09-12 11:53 ` [PATCH 2/5] ipc/sem: rework task wakeups Davidlohr Bueso
2016-09-13 18:04   ` Manfred Spraul
2016-09-14 15:45     ` Davidlohr Bueso
2016-09-18 14:37   ` Manfred Spraul
2016-09-18 18:26     ` Davidlohr Bueso
2016-09-12 11:53 ` [PATCH 3/5] ipc/sem: optimize perform_atomic_semop() Davidlohr Bueso
2016-09-12 17:56   ` Manfred Spraul
2016-09-13  8:33     ` Davidlohr Bueso
2016-09-19  4:41       ` Manfred Spraul
2016-09-12 11:53 ` [PATCH 4/5] ipc/sem: explicitly inline check_restart Davidlohr Bueso
2016-09-12 11:53 ` [PATCH 5/5] ipc/sem: use proper list api for pending_list wakeups Davidlohr Bueso
2016-09-18 17:51   ` Manfred Spraul
  -- strict thread matches above, loose matches on Subject: below --
2016-09-18 19:11 [PATCH -next v2 0/5] ipc/sem: semop(2) improvements Davidlohr Bueso
2016-09-18 19:11 ` [PATCH 1/5] ipc/sem: do not call wake_sem_queue_do() prematurely Davidlohr Bueso

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=20160913081441.GA32365@linux-80c1.suse \
    --to=dave@stgolabs.net \
    --cc=akpm@linux-foundation.org \
    --cc=dbueso@suse.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=manfred@colorfullife.com \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).