linux-kernel - Re: [f2fs-dev] [PATCH 2/3] f2fs: introduce FITRIM in f2fs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20141001150714.GB24084@jaegeuk-mac02.hsd1.ca.comcast.net>
Date:	Wed, 1 Oct 2014 08:07:14 -0700
From:	Jaegeuk Kim <jaegeuk@...nel.org>
To:	Chao Yu <chao2.yu@...sung.com>
Cc:	linux-kernel@...r.kernel.org,
	linux-f2fs-devel@...ts.sourceforge.net
Subject: Re: [f2fs-dev] [PATCH 2/3] f2fs: introduce FITRIM in f2fs_ioctl

On Tue, Sep 30, 2014 at 02:01:58PM +0800, Chao Yu wrote:
> > -----Original Message-----
> > From: Jaegeuk Kim [mailto:jaegeuk@...nel.org]
> > Sent: Tuesday, September 23, 2014 12:53 PM
> > To: linux-kernel@...r.kernel.org; linux-fsdevel@...r.kernel.org;
> > linux-f2fs-devel@...ts.sourceforge.net
> > Cc: Jaegeuk Kim
> > Subject: [f2fs-dev] [PATCH 2/3] f2fs: introduce FITRIM in f2fs_ioctl
> > 
> > This patch introduces FITRIM in f2fs_ioctl.
> > In this case, f2fs will issue small discards and prefree discards as many as
> > possible for the given area.
> > 
> > Signed-off-by: Jaegeuk Kim <jaegeuk@...nel.org>
> 
> Looks good!
> 
> Reviewed-by: Chao Yu <chao2.yu@...sung.com>
> 
> > +
> >  	/* zero block will be discarded through the prefree list */
> >  	if (!se->valid_blocks || se->valid_blocks == max_blocks)
> >  		return;
> > 
> > +	dmap = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
> 
> We can afford 64 bytes allocation in stack, how about altering dmap to a local
> array to reduce memory pressure at that moment and avoid delay of allocation?

It's not a big deal.
Fixed.
Thanks,

> 
> > +	if (!dmap)
> > +		return;
> > +
--
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/