From: Nick Piggin <nickpiggin@yahoo.com.au>
To: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Johannes Weiner <hannes@cmpxchg.org>,
David Miller <davem@davemloft.net>,
Dave Airlie <airlied@gmail.com>, Paul Menage <menage@google.com>,
kamezawa.hiroyu@jp.fujitsu.com,
Balbir Singh <balbir@linux.vnet.ibm.com>,
Arjan van de Ven <arjan@infradead.org>, Jan Kara <jack@suse.cz>,
Jes Sorensen <jes@sgi.com>,
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>,
dada1@cosmosbay.com, Alexey Dobriyan <adobriyan@gmail.com>,
Jens Axboe <jens.axboe@oracle.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Nick Piggin <npiggin@suse.de>, Al Viro <viro@zeniv.linux.org.uk>,
Rik van Riel <riel@redhat.com>,
Pekka Enberg <penberg@cs.helsinki.fi>
Subject: Re: [PATCH V2 1/4] vmalloc: introduce vfree_atomic()
Date: Tue, 18 Nov 2008 20:19:42 +1100 [thread overview]
Message-ID: <200811182019.44064.nickpiggin@yahoo.com.au> (raw)
In-Reply-To: <492281F7.3000107@cn.fujitsu.com>
On Tuesday 18 November 2008 19:51, Lai Jiangshan wrote:
> fdtable and sysipc use vfree() in RCU callback. this patch
> introduce vfree_atomic() for them.
AFAIKS, vfree is usable from atomic context? What am I missing?
Actually, one could argue that we don't want to perform such
costly operations in the atomic context, however with lazy
unmapping, vfree is very cheap now (amortized, at least).
But it should be much cheaper on average not to schedule this in
another context.
If there was any concern about the TLB flush from atomic context,
we should just defer the lazy flushing, rather than every single
vunmap.
next prev parent reply other threads:[~2008-11-18 9:20 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-17 12:26 [PATCH V2 1/1] mm: introduce kvmalloc()/kvfree() Lai Jiangshan
2008-11-17 13:14 ` Johannes Weiner
2008-11-18 0:28 ` Lai Jiangshan
2008-11-18 8:50 ` [PATCH V2 0/4] use kvmalloc()/kvfree() the second part, about RCU Lai Jiangshan
2008-11-18 8:51 ` [PATCH V2 1/4] vmalloc: introduce vfree_atomic() Lai Jiangshan
2008-11-18 9:19 ` Nick Piggin [this message]
2008-11-18 11:38 ` Lai Jiangshan
2008-11-18 12:05 ` Nick Piggin
2008-11-18 8:51 ` [PATCH V2 2/4] mm: introduce kvfree_atomic() Lai Jiangshan
2008-11-18 8:51 ` [PATCH V2 3/4] files: use kvmalloc()/kvfree()/kvfree_atomic() Lai Jiangshan
2008-11-18 8:51 ` [PATCH V2 4/4] sysipc: use kvmalloc()/kvfree_atomic() Lai Jiangshan
2008-11-18 6:57 ` [PATCH V2 1/1] mm: introduce kvmalloc()/kvfree() Pekka Enberg
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=200811182019.44064.nickpiggin@yahoo.com.au \
--to=nickpiggin@yahoo.com.au \
--cc=adobriyan@gmail.com \
--cc=airlied@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=arjan@infradead.org \
--cc=balbir@linux.vnet.ibm.com \
--cc=dada1@cosmosbay.com \
--cc=davem@davemloft.net \
--cc=hannes@cmpxchg.org \
--cc=jack@suse.cz \
--cc=jens.axboe@oracle.com \
--cc=jes@sgi.com \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=kosaki.motohiro@jp.fujitsu.com \
--cc=laijs@cn.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=menage@google.com \
--cc=npiggin@suse.de \
--cc=paulmck@linux.vnet.ibm.com \
--cc=penberg@cs.helsinki.fi \
--cc=riel@redhat.com \
--cc=viro@zeniv.linux.org.uk \
/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