From: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
To: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: linux-kernel@vger.kernel.org, Lars-Peter Clausen <lars@metafoo.de>
Subject: Re: [PATCH 3/7] regmap: Add a mutex to guard the sync operation
Date: Wed, 28 Sep 2011 15:24:06 +0100 [thread overview]
Message-ID: <20110928142406.GA12438@opensource.wolfsonmicro.com> (raw)
In-Reply-To: <20110928125249.GH3279@opensource.wolfsonmicro.com>
On Wed, Sep 28, 2011 at 01:52:50PM +0100, Mark Brown wrote:
> On Wed, Sep 28, 2011 at 11:43:43AM +0100, Dimitris Papastamos wrote:
>
> > + mutex_lock(&map->sync_lock);
> > dev_dbg(map->dev, "Syncing %s cache\n",
> > map->cache_ops->name);
> > name = map->cache_ops->name;
> > @@ -254,6 +257,7 @@ int regcache_sync(struct regmap *map)
> > }
> > out:
> > trace_regcache_sync(map->dev, name, "stop");
> > + mutex_unlock(&map->sync_lock);
>
> Shouldn't we either be taking the regmap lock when doing the sync or
> otherwise guarding against something other than a cache sync?
Em the main issue is that the sync() implementation will use
regmap_write() which will grab map->lock. To avoid this we could have
gone and used directly the lockless _regmap_write() but that's
static. To be honest, it feels cleaner to have only 1 lock to guard
the map so maybe we should get rid of map->sync_lock.
next prev parent reply other threads:[~2011-09-28 14:24 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-28 10:43 [PATCH 1/7] regmap: Fix regcache_sync generic implementation Dimitris Papastamos
2011-09-28 10:43 ` [PATCH 2/7] regmap: Modify map->cache_bypass directly Dimitris Papastamos
2011-09-28 12:56 ` Mark Brown
2011-09-28 10:43 ` [PATCH 3/7] regmap: Add a mutex to guard the sync operation Dimitris Papastamos
2011-09-28 12:52 ` Mark Brown
2011-09-28 14:24 ` Dimitris Papastamos [this message]
2011-09-28 15:19 ` Mark Brown
2011-09-28 15:52 ` Dimitris Papastamos
2011-09-28 10:43 ` [PATCH 4/7] regmap: Save/restore the bypass state upon syncing Dimitris Papastamos
2011-09-28 10:43 ` [PATCH 5/7] regmap: Grab the lock in regcache_cache_only() Dimitris Papastamos
2011-09-28 12:57 ` Mark Brown
2011-09-28 10:43 ` [PATCH 6/7] regmap: Implement regcache_cache_bypass helper function Dimitris Papastamos
2011-09-28 10:43 ` [PATCH 7/7] regmap: Ensure we scream if we enable cache bypass/only at the same time Dimitris Papastamos
2011-09-28 12:56 ` [PATCH 1/7] regmap: Fix regcache_sync generic implementation Mark Brown
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