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9730348075
Increase the standard cacheline size to avoid having locks in the same cacheline. Cavium's ThunderX core implements cache lines of 128 byte size. With current granulare size of 64 bytes (L1_CACHE_SHIFT=6) two locks could share the same cache line leading a performance degradation. Increasing the size fixes that. Increasing the size has no negative impact to cache invalidation on systems with a smaller cache line. There is an impact on memory usage, but that's not too important for arm64 use cases. Signed-off-by: Tirumalesh Chalamarla <tchalamarla@cavium.com> Signed-off-by: Robert Richter <rrichter@cavium.com> Acked-by: Timur Tabi <timur@codeaurora.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
45 lines
1.3 KiB
C
45 lines
1.3 KiB
C
/*
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* Copyright (C) 2012 ARM Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef __ASM_CACHE_H
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#define __ASM_CACHE_H
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#include <asm/cachetype.h>
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#define L1_CACHE_SHIFT 7
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#define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT)
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/*
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* Memory returned by kmalloc() may be used for DMA, so we must make
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* sure that all such allocations are cache aligned. Otherwise,
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* unrelated code may cause parts of the buffer to be read into the
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* cache before the transfer is done, causing old data to be seen by
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* the CPU.
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*/
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#define ARCH_DMA_MINALIGN L1_CACHE_BYTES
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#ifndef __ASSEMBLY__
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#define __read_mostly __attribute__((__section__(".data..read_mostly")))
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static inline int cache_line_size(void)
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{
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u32 cwg = cache_type_cwg();
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return cwg ? 4 << cwg : L1_CACHE_BYTES;
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}
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#endif /* __ASSEMBLY__ */
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#endif
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