Re: Lockdep warning when using REGCACHE_RBTREE

From	Mark Brown <broonie@kernel.org>
Newsgroups	linux.kernel
Subject	Re: Lockdep warning when using REGCACHE_RBTREE
Date	2016-01-15 13:00 +0100
Message-ID	<qRbcS-5yd-7@gated-at.bofh.it> (permalink)
References	<qQYIG-5f6-19@gated-at.bofh.it> <qR9b4-4eJ-15@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

[Multipart message — attachments visible in raw view] - view raw

On Fri, Jan 15, 2016 at 10:45:41AM +0100, Peter Zijlstra wrote:

> So _regmap_write() does: map->lock(map->lock_arg)

> Which isn't very enlightening, since that can be a mutex or a spinlock,
> the above strongly suggests spinlock though.

> Looking at __regmap_init(), this seems to depend on:

>   (bus && bus->fast_io) || config->fast_io

> now, afaict, regmap_mmio is used in this case, which has .fast_io =
> true.

> So yeah, fail.

Indeed, that'd do it.  It hadn't occurred to me that someone would be
using MMIO with an rbtree cache.

Back to linux.kernel | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

Lockdep warning when using REGCACHE_RBTREE Stefan Agner <stefan@agner.ch> - 2016-01-14 23:40 +0100
  Re: Lockdep warning when using REGCACHE_RBTREE Mark Brown <broonie@kernel.org> - 2016-01-15 01:10 +0100
    Re: Lockdep warning when using REGCACHE_RBTREE Stefan Agner <stefan@agner.ch> - 2016-01-15 02:20 +0100
      Re: Lockdep warning when using REGCACHE_RBTREE Mark Brown <broonie@kernel.org> - 2016-01-15 17:30 +0100
        Re: Lockdep warning when using REGCACHE_RBTREE Stefan Agner <stefan@agner.ch> - 2016-01-15 20:20 +0100
  Re: Lockdep warning when using REGCACHE_RBTREE Peter Zijlstra <peterz@infradead.org> - 2016-01-15 10:50 +0100
    Re: Lockdep warning when using REGCACHE_RBTREE Mark Brown <broonie@kernel.org> - 2016-01-15 13:00 +0100

csiph-web