linux/kernel/dma
Robin Murphy c6ccd09880 dma/pool: Avoid allocating redundant pools
On smaller systems, e.g. embedded arm64, it is common for all memory
to end up in ZONE_DMA32 or even ZONE_DMA. In such cases it is redundant
to allocate a nominal pool for an empty higher zone that just ends up
coming from a lower zone that should already have its own pool anyway.
We already have logic to skip allocating a ZONE_DMA pool when that is
empty, so generalise that to save memory in the case of other zones too.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Vladimir Kondratiev <vladimir.kondratiev@mobileye.com>
Reviewed-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/8ab8d8a620dee0109f33f5cb63d6bfeed35aac37.1768230104.git.robin.murphy@arm.com
2026-01-14 11:00:00 +01:00
..
Kconfig
Makefile
coherent.c
contiguous.c dma: contiguous: Reserve default CMA heap 2025-10-18 21:31:21 +05:30
debug.c
debug.h
direct.c VFIO updates for v6.19-rc1 2025-12-04 18:42:48 -08:00
direct.h
dummy.c dma-mapping: convert dummy ops to physical address mapping 2025-10-29 10:27:29 +01:00
map_benchmark.c tools/dma: move dma_map_benchmark from selftests to tools/dma 2025-10-29 09:41:40 +01:00
mapping.c dma-mapping: remove unused map_page callback 2025-10-29 10:27:31 +01:00
ops_helpers.c dma-mapping: remove unused map_page callback 2025-10-29 10:27:31 +01:00
pool.c dma/pool: Avoid allocating redundant pools 2026-01-14 11:00:00 +01:00
remap.c
swiotlb.c mm: make INVALID_PHYS_ADDR a generic macro 2025-11-16 17:28:26 -08:00