[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <18115.45316.702491.681906@cargo.ozlabs.ibm.com>
Date: Thu, 16 Aug 2007 12:05:56 +1000
From: Paul Mackerras <paulus@...ba.org>
To: Herbert Xu <herbert@...dor.apana.org.au>
Cc: Christoph Lameter <clameter@....com>,
"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>,
Satyam Sharma <satyam@...radead.org>,
Stefan Richter <stefanr@...6.in-berlin.de>,
Chris Snook <csnook@...hat.com>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
linux-arch@...r.kernel.org,
Linus Torvalds <torvalds@...ux-foundation.org>,
netdev@...r.kernel.org, Andrew Morton <akpm@...ux-foundation.org>,
ak@...e.de, heiko.carstens@...ibm.com, davem@...emloft.net,
schwidefsky@...ibm.com, wensong@...ux-vs.org, horms@...ge.net.au,
wjiang@...ilience.com, cfriesen@...tel.com, zlynx@....org,
rpjday@...dspring.com, jesper.juhl@...il.com,
segher@...nel.crashing.org
Subject: Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
Herbert Xu writes:
> See sk_stream_mem_schedule in net/core/stream.c:
>
> /* Under limit. */
> if (atomic_read(sk->sk_prot->memory_allocated) < sk->sk_prot->sysctl_mem[0]) {
> if (*sk->sk_prot->memory_pressure)
> *sk->sk_prot->memory_pressure = 0;
> return 1;
> }
>
> /* Over hard limit. */
> if (atomic_read(sk->sk_prot->memory_allocated) > sk->sk_prot->sysctl_mem[2]) {
> sk->sk_prot->enter_memory_pressure();
> goto suppress_allocation;
> }
>
> We don't need to reload sk->sk_prot->memory_allocated here.
Are you sure? How do you know some other CPU hasn't changed the value
in between?
Paul.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists