The Linux Kernel Mailing List
 help / color / mirror / Atom feed
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andrew Morton <akpm@osdl.org>, Alan Cox <alan@redhat.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] do_acct_process: don't take tty_mutex
Date: Tue, 24 Oct 2006 11:48:15 +0200	[thread overview]
Message-ID: <1161683295.24143.12.camel@taijtu> (raw)
In-Reply-To: <20061023135644.GA1501@oleg>

On Mon, 2006-10-23 at 17:56 +0400, Oleg Nesterov wrote:
> Depends on
> 	tty-signal-tty-locking.patch
> 
> No need to take the global tty_mutex, signal->tty->driver can't go away
> while we are holding ->siglock.
> 
> Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl

> --- rc2-mm2/kernel/acct.c~	2006-10-22 19:28:17.000000000 +0400
> +++ rc2-mm2/kernel/acct.c	2006-10-23 17:09:12.000000000 +0400
> @@ -484,12 +484,9 @@ static void do_acct_process(struct file 
>  	ac.ac_ppid = current->parent->tgid;
>  #endif
>  
> -	mutex_lock(&tty_mutex);
> -	tty = get_current_tty();
> -	ac.ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0;
> -	mutex_unlock(&tty_mutex);
> -
>  	spin_lock_irq(&current->sighand->siglock);
> +	tty = current->signal->tty;
> +	ac.ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0;
>  	ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
>  	ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
>  	ac.ac_flag = pacct->ac_flag;
> 


      reply	other threads:[~2006-10-24  9:47 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-10-23 13:56 [PATCH] do_acct_process: don't take tty_mutex Oleg Nesterov
2006-10-24  9:48 ` Peter Zijlstra [this message]

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=1161683295.24143.12.camel@taijtu \
    --to=a.p.zijlstra@chello.nl \
    --cc=akpm@osdl.org \
    --cc=alan@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=oleg@tv-sign.ru \
    /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