From: Peter Zijlstra <peterz@infradead.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>, Ingo Molnar <mingo@redhat.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
"Paul E.McKenney" <paulmck@linux.vnet.ibm.com>,
Waiman Long <Waiman.Long@hp.com>,
linux-kernel@vger.kernel.org
Subject: Re: qrwlock && read-after-read
Date: Tue, 4 Aug 2015 19:32:32 +0200 [thread overview]
Message-ID: <20150804173232.GS25159@twins.programming.kicks-ass.net> (raw)
In-Reply-To: <20150804134043.GA24252@redhat.com>
On Tue, Aug 04, 2015 at 03:40:43PM +0200, Oleg Nesterov wrote:
> Lets fix the lockdep annotaions?
>
> Oleg.
>
> --- x/include/linux/rwlock_api_smp.h
> +++ x/include/linux/rwlock_api_smp.h
> @@ -146,7 +146,7 @@ static inline int __raw_write_trylock(rw
> static inline void __raw_read_lock(rwlock_t *lock)
> {
> preempt_disable();
> - rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
> + lock_acquire(..., /* read */ in_interrupt() 2 : 1, ...);
> LOCK_CONTENDED(lock, do_raw_read_trylock, do_raw_read_lock);
> }
I think that suffers the same problems we had before; see:
8acd91e86208 ("locking/lockdep: Revert qrwlock recusive stuff")
next prev parent reply other threads:[~2015-08-04 17:32 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-04 13:00 qrwlock && read-after-read Oleg Nesterov
2015-08-04 13:10 ` Peter Zijlstra
2015-08-04 13:40 ` Oleg Nesterov
2015-08-04 17:32 ` Peter Zijlstra [this message]
2015-08-04 13:51 ` Linus Torvalds
2015-08-05 13:08 ` Oleg Nesterov
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=20150804173232.GS25159@twins.programming.kicks-ass.net \
--to=peterz@infradead.org \
--cc=Waiman.Long@hp.com \
--cc=arnd@arndb.de \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=oleg@redhat.com \
--cc=paulmck@linux.vnet.ibm.com \
--cc=torvalds@linux-foundation.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.