On Wed, Sep 05, 2018 at 11:22:32AM +0200, David Sterba wrote:
On Thu, Aug 30, 2018 at 06:08:33PM +0000, Sasha Levin wrote:
From: Nikolay Borisov nborisov@suse.com
[ Upstream commit 2556fbb0bead7929ddf67f8b4184f434cee4e7d7 ]
do_chunk_alloc implements logic to detect whether there is currently pending chunk allocation (by means of space_info->chunk_alloc being set) and if so it loops around to the 'again' label. Additionally, based on the state of the space_info (e.g. whether it's full or not) and the return value of should_alloc_chunk() it decides whether this is a "hard" error (ENOSPC) or we can just return 0.
This patch refactors all of this:
- Put order to the scattered ifs handling the various cases in an
easy-to-read if {} else if{} branches. This makes clear the various cases we are interested in handling.
- Call should_alloc_chunk only once and use the result in the
if/else if constructs. All of this is done under space_info->lock, so even before multiple calls of should_alloc_chunk were unnecessary.
- Rewrite the "do {} while()" loop currently implemented via label
into an explicit loop construct.
- Move the mutex locking for the case where the caller is the one doing
the allocation. For the case where the caller needs to wait a concurrent allocation, introduce a pair of mutex_lock/mutex_unlock to act as a barrier and reword the comment.
- Switch local vars to bool type where pertinent.
All in all this shouldn't introduce any functional changes.
Unless there are other followup patches "No functional changes" is a hint for autosel not to pick the patch.
Out it goes, thanks!