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Revert "arm64: Increase the max granular size"
authorCatalin Marinas <catalin.marinas@arm.com>
Fri, 11 May 2018 12:25:49 +0000 (13:25 +0100)
committerCatalin Marinas <catalin.marinas@arm.com>
Fri, 11 May 2018 13:21:33 +0000 (14:21 +0100)
This reverts commit 97303480753e48fb313dc0e15daaf11b0451cdb8.

Commit 97303480753e ("arm64: Increase the max granular size") increased
the cache line size to 128 to match Cavium ThunderX, apparently for some
performance benefit which could not be confirmed. This change, however,
has an impact on the network packet allocation in certain circumstances,
requiring slightly over a 4K page with a significant performance
degradation. The patch reverts L1_CACHE_SHIFT back to 6 (64-byte cache
line).

Cc: Will Deacon <will.deacon@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch/arm64/include/asm/cache.h

index 9bbffc7..1dd2c2d 100644 (file)
@@ -33,7 +33,7 @@
 #define ICACHE_POLICY_VIPT     2
 #define ICACHE_POLICY_PIPT     3
 
-#define L1_CACHE_SHIFT         7
+#define L1_CACHE_SHIFT         (6)
 #define L1_CACHE_BYTES         (1 << L1_CACHE_SHIFT)
 
 /*