blackbird-op-linux - Blackbird™ Linux sources for OpenPOWER

	Commit message (Collapse)	Author	Age	Files	Lines
*	[PATCH] elevator switching race	Jens Axboe	2006-06-08	1	-4/+3
\| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|	There's a race between shutting down one io scheduler and firing up the next, in which a new io could enter and cause the io scheduler to be invoked with bad or NULL data. To fix this, we need to maintain the queue lock for a bit longer. Unfortunately we cannot do that, since the elevator init requires to be run without the lock held. This isn't easily fixable, without also changing the mempool API. So split the initialization into two parts, and alloc-init operation and an attach operation. Then we can preallocate the io scheduler and related structures, and run the attach inside the lock after we detach the old one. This patch has survived 30 minutes of 1 second io scheduler switching with a very busy io load. Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
*	[BLOCK] noop-iosched: reimplementation of request dispatching	Tejun Heo	2005-11-12	1	-6/+79
\| \| \| \| \| \| \| \| \| \| \| \|	The original implementation directly used dispatch queue. As new generic dispatch queue imposes stricter rules over ioscheds and dispatch queue usage, this direct use becomes somewhat problematic. This patch reimplements noop-iosched such that it complies to generic iosched model better. Request merging with q->last_merge and rq->queuelist.prev/next work again now. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jens Axboe <axboe@suse.de
*	[BLOCK] Move all core block layer code to new block/ directory	Jens Axboe	2005-11-04	1	-0/+46
	drivers/block/ is right now a mix of core and driver parts. Lets move the core parts to a new top level directory. Al will move the fs/ related block parts to block/ next. Signed-off-by: Jens Axboe <axboe@suse.de>