From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: Seth Jennings <sjenning@linux.vnet.ibm.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>,
Greg Kroah-Hartman <gregkh@suse.de>,
Brian King <brking@linux.vnet.ibm.com>,
devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org,
Nitin Gupta <ngupta@vflare.org>
Subject: Re: [PATCH] staging: zcache: fix serialization bug in zv stats
Date: Tue, 3 Jan 2012 16:38:12 -0500 [thread overview]
Message-ID: <20120103213812.GL17472@phenom.dumpdata.com> (raw)
In-Reply-To: <4EFDF671.7020101@linux.vnet.ibm.com>
On Fri, Dec 30, 2011 at 11:35:45AM -0600, Seth Jennings wrote:
> On 12/30/2011 11:02 AM, Dan Magenheimer wrote:
> >> From: Seth Jennings [mailto:sjenning@linux.vnet.ibm.com]
> >> Sent: Friday, December 30, 2011 9:42 AM
> >> To: Greg Kroah-Hartman
> >> Cc: Seth Jennings; Dan Magenheimer; Brian King; devel@driverdev.osuosl.org; linux-
> >> kernel@vger.kernel.org
> >> Subject: [PATCH] staging: zcache: fix serialization bug in zv stats
> >>
> >> In a multithreaded workload, the zv_curr_dist_counts
> >> and zv_cumul_dist_counts statistics are being corrupted
> >> because the increments and decrements in zv_create
> >> and zv_free are not atomic.
> >>
> >> This patch converts these statistics and their corresponding
> >> increments/decrements/reads to atomic operations.
> >>
> >> Based on v3.2-rc7
> >>
> >> Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com>
> >
> > I'm inclined to nack this change, at least unless inside an #ifdef DEBUG,
>
> I guess I didn't respond to this suggestion. We could put #ifdef DEBUG
> around the updates in zv_create and zv_free and around the two sysfs
> *_show functions. Kinda messy though. I guess it might not matter
> if we'll be re-evaluating this whole thing soon.
Perhaps also add in the TODO file that we want to move the stats collection
out of the code and only be enabled if CONFIG_DEBUGFS is set? (Which granted means
we need to implement the stats output in debugfs instead of sysfs).
next prev parent reply other threads:[~2012-01-03 21:39 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <<1325263335-16254-1-git-send-email-sjenning@linux.vnet.ibm.com>
2011-12-30 17:02 ` [PATCH] staging: zcache: fix serialization bug in zv stats Dan Magenheimer
2011-12-30 17:27 ` Seth Jennings
2011-12-30 17:31 ` Dan Magenheimer
2011-12-30 17:35 ` Seth Jennings
2012-01-03 21:38 ` Konrad Rzeszutek Wilk [this message]
2011-12-30 16:42 Seth Jennings
2012-02-06 21:18 ` Seth Jennings
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=20120103213812.GL17472@phenom.dumpdata.com \
--to=konrad.wilk@oracle.com \
--cc=brking@linux.vnet.ibm.com \
--cc=dan.magenheimer@oracle.com \
--cc=devel@driverdev.osuosl.org \
--cc=gregkh@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=ngupta@vflare.org \
--cc=sjenning@linux.vnet.ibm.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 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.