linux/mm/dmapool.c, branch v3.0.44

mm/dmapool.c: use TASK_UNINTERRUPTIBLE in dma_pool_alloc()

2011-01-14T01:32:48Z

As it stands this code will degenerate into a busy-wait if the calling task has signal_pending(). Cc: Rolf Eike Beer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/dmapool.c: take lock only once in dma_pool_free()

2011-01-14T01:32:48Z

dma_pool_free() scans for the page to free in the pool list holding the pool lock. Then it releases the lock basically to acquire it immediately again. Modify the code to only take the lock once. This will do some additional loops and computations with the lock held in if memory debugging is activated. If it is not activated the only new operations with this lock is one if and one substraction. Signed-off-by: Rolf Eike Beer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: add a might_sleep_if() to dma_pool_alloc()

2010-10-26T23:52:08Z

Buggy drivers (e.g. fsl_udc) could call dma_pool_alloc from atomic context with GFP_KERNEL. In most instances, the first pool_alloc_page call would succeed and the sleeping functions would never be called. This allowed the buggy drivers to slip through the cracks. Add a might_sleep_if() checking for __GFP_WAIT in flags. Signed-off-by: Dima Zavin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dmapools: protect page_list walk in show_pools()

2009-07-01T01:56:00Z

show_pools() walks the page_list of a pool w/o protection against the list modifications in alloc/free. Take pool->lock to avoid stomping into nirvana. Signed-off-by: Thomas Gleixner Signed-off-by: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

dmapool: enable debugging for CONFIG_SLUB_DEBUG_ON too

2008-04-28T15:58:20Z

Previously it was only enabled for CONFIG_DEBUG_SLAB. Not hooked into the slub runtime debug configuration, so you currently only get it with CONFIG_SLUB_DEBUG_ON, not plain CONFIG_SLUB_DEBUG Acked-by: Matthew Wilcox Signed-off-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

pool: Improve memory usage for devices which can't cross boundaries

2007-12-04T15:39:58Z

The previous implementation simply refused to allocate more than a boundary's worth of data from an entire page. Some users didn't know this, so specified things like SMP_CACHE_BYTES, not realising the horrible waste of memory that this was. It's fairly easy to correct this problem, just by ensuring we don't cross a boundary within a page. This even helps drivers like EHCI (which can't cross a 4k boundary) on machines with larger page sizes. Signed-off-by: Matthew Wilcox Acked-by: David S. Miller

Change dmapool free block management

2007-12-04T15:39:57Z

Use a list of free blocks within a page instead of using a bitmap. Update documentation to reflect this. As well as being a slight reduction in memory allocation, locked ops and lines of code, it speeds up a transaction processing benchmark by 0.4%. Signed-off-by: Matthew Wilcox

dmapool: Tidy up includes and add comments

2007-12-04T15:39:57Z

We were missing a copyright statement and license, so add GPLv2, David Brownell's copyright and my copyright. The asm/io.h include was superfluous, but we were missing a few other necessary includes. Signed-off-by: Matthew Wilcox

dmapool: Validate parameters to dma_pool_create

2007-12-04T15:39:56Z

Check that 'align' is a power of two, like the API specifies. Align 'size' to 'align' correctly -- the current code has an off-by-one. The ALIGN macro in kernel.h doesn't. Signed-off-by: Matthew Wilcox Acked-by: David S. Miller

Avoid taking waitqueue lock in dmapool

2007-12-04T15:39:56Z

With one trivial change (taking the lock slightly earlier on wakeup from schedule), all uses of the waitq are under the pool lock, so we can use the locked (or __) versions of the wait queue functions, and avoid the extra spinlock. Signed-off-by: Matthew Wilcox Acked-by: David S. Miller