linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: David Miller <davem@davemloft.net>
To: mhocko@suse.cz
Cc: linux-mm@kvack.org, akpm@linux-foundation.org,
	hannes@cmpxchg.org, rientjes@google.com, david@fromorbit.com,
	tytso@mit.edu, mgorman@suse.de,
	penguin-kernel@I-love.SAKURA.ne.jp, sparclinux@vger.kernel.org,
	vipul@chelsio.com, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sparc: clarify __GFP_NOFAIL allocation
Date: Mon, 02 Mar 2015 16:45:45 -0500 (EST)	[thread overview]
Message-ID: <20150302.164545.1603268042858889224.davem@davemloft.net> (raw)
In-Reply-To: <20150302213610.GA31974@dhcp22.suse.cz>

From: Michal Hocko <mhocko@suse.cz>
Date: Mon, 2 Mar 2015 22:36:10 +0100

> 920c3ed74134 ([SPARC64]: Add basic infrastructure for MD add/remove
> notification.) has added __GFP_NOFAIL for the allocation request but
> it hasn't mentioned why is this strict requirement really needed.
> The code was handling an allocation failure and propagated it properly
> up the callchain so it is not clear why it is needed.
> 
> Dave has clarified the intention when I tried to remove the flag as not
> being necessary:
> "
> It is a serious failure.
> 
> If we miss an MDESC update due to this allocation failure, the update
> is not an event which gets retransmitted so we will lose the updated
> machine description forever.
> 
> We really need this allocation to succeed.
> "
> 
> So add a comment to clarify the nofail flag and get rid of the failure
> check because __GFP_NOFAIL allocation doesn't fail.
> 
> Signed-off-by: Michal Hocko <mhocko@suse.cz>

Acked-by: David S. Miller <davem@davemloft.net>

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2015-03-02 21:45 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-02 13:54 [RFC PATCH 0/4] Clarify and cleanup some __GFP_NOFAIL usage Michal Hocko
2015-03-02 13:54 ` [RFC 1/4] mm: Clarify __GFP_NOFAIL deprecation status Michal Hocko
2015-03-02 20:34   ` David Rientjes
2015-03-02 13:54 ` [RFC 2/4] jbd2: revert must-not-fail allocation loops back to GFP_NOFAIL Michal Hocko
2015-03-02 20:33   ` David Rientjes
2015-03-02 21:42     ` Michal Hocko
2015-03-02 13:54 ` [RFC 3/4] sparc: remove __GFP_NOFAIL reuquirement Michal Hocko
2015-03-02 20:04   ` David Miller
2015-03-02 20:33     ` Michal Hocko
2015-03-02 20:44       ` David Miller
2015-03-02 21:36         ` [PATCH] sparc: clarify __GFP_NOFAIL allocation Michal Hocko
2015-03-02 21:45           ` David Miller [this message]
2015-03-02 13:54 ` [RFC 4/4] cxgb4: drop " Michal Hocko
2015-03-03 12:22   ` Tetsuo Handa
2015-03-03 13:18     ` Michal Hocko

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=20150302.164545.1603268042858889224.davem@davemloft.net \
    --to=davem@davemloft.net \
    --cc=akpm@linux-foundation.org \
    --cc=david@fromorbit.com \
    --cc=hannes@cmpxchg.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@suse.de \
    --cc=mhocko@suse.cz \
    --cc=netdev@vger.kernel.org \
    --cc=penguin-kernel@I-love.SAKURA.ne.jp \
    --cc=rientjes@google.com \
    --cc=sparclinux@vger.kernel.org \
    --cc=tytso@mit.edu \
    --cc=vipul@chelsio.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