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Subject[PATCH] Revert "arm64: Increase the max granular size"
Date
Reverts commit 97303480753e ("arm64: Increase the max granular size").

The commit 97303480753e ("arm64: Increase the max granular size") will
degrade system performente in some cpus.

We test wifi network throughput with iperf on Qualcomm msm8996 CPU:
----------------
run on host:
# iperf -s
run on device:
# iperf -c <device-ip-addr> -t 100 -i 1
----------------

Test result:
----------------
with commit 97303480753e ("arm64: Increase the max granular size"):
172MBits/sec

without commit 97303480753e ("arm64: Increase the max granular size"):
230MBits/sec
----------------

Some module like slab/net will use the L1_CACHE_SHIFT, so if we do not
set the parameter correctly, it may affect the system performance.

So revert the commit.

Cc: stable@vger.kernel.org
Signed-off-by: Ganesh Mahendran <opensource.ganesh@gmail.com>
---
arch/arm64/include/asm/cache.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/cache.h b/arch/arm64/include/asm/cache.h
index 5082b30..bde4499 100644
--- a/arch/arm64/include/asm/cache.h
+++ b/arch/arm64/include/asm/cache.h
@@ -18,7 +18,7 @@

#include <asm/cachetype.h>

-#define L1_CACHE_SHIFT 7
+#define L1_CACHE_SHIFT 6
#define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT)

/*
--
1.7.9.5
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