diff mbox series

[v5,10/15] arm64: Allow kmalloc() caches aligned to the smaller cache_line_size()

Message ID 20230524171904.3967031-11-catalin.marinas@arm.com (mailing list archive)
State New
Headers show
Series mm, dma, arm64: Reduce ARCH_KMALLOC_MINALIGN to 8 | expand

Commit Message

Catalin Marinas May 24, 2023, 5:18 p.m. UTC 
On arm64, ARCH_DMA_MINALIGN is 128, larger than the cache line size on
most of the current platforms (typically 64). Define
ARCH_KMALLOC_MINALIGN to 8 (the default for architectures without their
own ARCH_DMA_MINALIGN) and override dma_get_cache_alignment() to return
cache_line_size(), probed at run-time. The kmalloc() caches will be
limited to the cache line size. This will allow the additional
kmalloc-{64,192} caches on most arm64 platforms.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
---
 arch/arm64/include/asm/cache.h | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h
index a51e6e8f3171..ceb368d33bf4 100644
--- a/arch/arm64/include/asm/cache.h
+++ b/arch/arm64/include/asm/cache.h
@@ -33,6 +33,7 @@ 
  * the CPU.
  */
 #define ARCH_DMA_MINALIGN	(128)
+#define ARCH_KMALLOC_MINALIGN	(8)
 
 #ifndef __ASSEMBLY__
 
@@ -90,6 +91,8 @@  static inline int cache_line_size_of_cpu(void)
 
 int cache_line_size(void);
 
+#define dma_get_cache_alignment	cache_line_size
+
 /*
  * Read the effective value of CTR_EL0.
  *