Re: [PATCH 4/4] ext4: Wait for proper transaction commit on fsync

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue 08-12-09 22:51:20, tytso@xxxxxxx wrote:
> On Mon, Nov 16, 2009 at 11:43:31AM +0100, Jan Kara wrote:
> > > Why do we need an atomic_t here at all?  It's not clear it's
> > > necessary.  What specific race are you worried about?
> >   Well, i_[data]sync_tid are set and read from several places which aren't
> > currently synchronized against each other and I din't want to introduce any
> > synchronization. So atomic_t seemed like a clean way of making clear that
> > loads / stores from those fields are atomic, regardless of architecture,
> > memory alignment or whatever insanity that might make us see just half
> > overwritten field.  On all archs where this means just plain stores / loads
> > (such as x86), there's no performance hit since the operations are
> > implemented as such.
> 
> Sorry for not responding to this one sooner, but see this URL:
> 
> http://digitalvampire.org/blog/index.php/2007/05/13/atomic-cargo-cults/
  Thanks for the pointer :) It's a good reading...

									Honza
-- 
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Reiser Filesystem Development]     [Ceph FS]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite National Park]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]     [Linux Media]

  Powered by Linux