kernel/linux.git/include/linux/iocontext.h, branch linux-2.6.28.y

block: blkdev.h cleanup, move iocontext stuff to iocontext.h

2008-07-03T11:21:14+00:00

Signed-off-by: Jens Axboe

io context: increment task attachment count in ioc_task_link()

2008-04-15T07:25:33+00:00

Thanks to Nikanth Karthikesan for reporting this. Signed-off-by: Jens Axboe

cfq-iosched: fix rcu freeing of cfq io contexts

2008-04-02T13:42:20+00:00

SLAB_DESTROY_BY_RCU is not a direct substitute for normal call_rcu() freeing, since it'll page freeing but NOT object freeing. So change cfq to do the freeing on its own. Signed-off-by: Fabio Checconi Acked-by: Paul E. McKenney Signed-off-by: Jens Axboe

cfq-iosched: add hlist for browsing parallel to the radix tree

2008-02-19T09:04:00+00:00

It's cumbersome to browse a radix tree from start to finish, especially since we modify keys when a process exits. So add a hlist for the single purpose of browsing over all known cfq_io_contexts, used for exit, io prio change, etc. This fixes http://bugzilla.kernel.org/show_bug.cgi?id=9948 Signed-off-by: Jens Axboe

block: cfq: make the io contect sharing lockless

2008-01-28T09:50:33+00:00

The io context sharing introduced a per-ioc spinlock, that would protect the cfq io context lookup. That is a regression from the original, since we never needed any locking there because the ioc/cic were process private. The cic lookup is changed from an rbtree construct to a radix tree, which we can then use RCU to make the reader side lockless. That is the performance critical path, modifying the radix tree is only done on process creation (when that process first does IO, actually) and on process exit (if that process has done IO). As it so happens, radix trees are also much faster for this type of lookup where the key is a pointer. It's a very sparse tree. Signed-off-by: Jens Axboe

io context sharing: preliminary support

2008-01-28T09:50:31+00:00

Detach task state from ioc, instead keep track of how many processes are accessing the ioc. Signed-off-by: Jens Axboe

ioprio: move io priority from task_struct to io_context

2008-01-28T09:50:29+00:00

This is where it belongs and then it doesn't take up space for a process that doesn't do IO. Signed-off-by: Jens Axboe