linux/arch/s390/include/asm/cache.h
Horst Hartmann dd30ac3274 [S390] net: provide architecture specific NET_SKB_PAD
NET_SKB_PAD has been increased from 32 to 64 and later to
max(32, L1_CACHE_BYTES). This led to a 25% throughput decrease for
streaming workloads accompanied by a 37% CPU cost increase on s390.
Define a architecture specific NET_SKB_PAD with the old value of 32.

Signed-off-by: Horst Hartmann <horsth@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-02-17 13:13:59 +01:00

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C

/*
* include/asm-s390/cache.h
*
* S390 version
* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
*
* Derived from "include/asm-i386/cache.h"
* Copyright (C) 1992, Linus Torvalds
*/
#ifndef __ARCH_S390_CACHE_H
#define __ARCH_S390_CACHE_H
#define L1_CACHE_BYTES 256
#define L1_CACHE_SHIFT 8
#define NET_SKB_PAD 32
#define __read_mostly __attribute__((__section__(".data..read_mostly")))
#endif