2012/2/23 Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>: > The Contiguous Memory Allocator is a set of helper functions for DMA > mapping framework that improves allocations of contiguous memory chunks. > > CMA grabs memory on system boot, marks it with MIGRATE_CMA migrate type > and gives back to the system. Kernel is allowed to allocate only movable > pages within CMA's managed memory so that it can be used for example for > page cache when DMA mapping do not use it. On > dma_alloc_from_contiguous() request such pages are migrated out of CMA > area to free required contiguous block and fulfill the request. This > allows to allocate large contiguous chunks of memory at any time > assuming that there is enough free memory available in the system. > > This code is heavily based on earlier works by Michal Nazarewicz. > > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> > Signed-off-by: Michal Nazarewicz <mina86@xxxxxxxxxx> > Acked-by: Arnd Bergmann <arnd@xxxxxxxx> > Tested-by: Rob Clark <rob.clark@xxxxxxxxxx> > Tested-by: Ohad Ben-Cohen <ohad@xxxxxxxxxx> > Tested-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx> > Tested-by: Robert Nelson <robertcnelson@xxxxxxxxx> if there is a /proc/cmainfo like /proc/slabinfo, it might be helpful to people as we can see the usage of CMA clearly. Thanks barry -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>