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author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-08 10:10:11 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-08 10:10:11 -0700 |
commit | 45d7f32c7a43cbb9592886d38190e379e2eb2226 (patch) | |
tree | ea68b67b1d2127527d856248c0485f2ed7e50088 /arch/tile/lib/memmove_32.c | |
parent | 53bcef60633086ad73683d01a4ef9ca678484d2d (diff) | |
parent | ab11b487402f97975f3ac1eeea09c82f4431481e (diff) | |
download | op-kernel-dev-45d7f32c7a43cbb9592886d38190e379e2eb2226.zip op-kernel-dev-45d7f32c7a43cbb9592886d38190e379e2eb2226.tar.gz |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
arch/tile: check kmalloc() result
arch/tile: catch up on various minor cleanups.
arch/tile: avoid erroneous error return for PTRACE_POKEUSR.
tile: set ARCH_KMALLOC_MINALIGN
tile: remove homegrown L1_CACHE_ALIGN macro
arch/tile: Miscellaneous cleanup changes.
arch/tile: Split the icache flush code off to a generic <arch> header.
arch/tile: Fix bug in support for atomic64_xx() ops.
arch/tile: Shrink the tile-opcode files considerably.
arch/tile: Add driver to enable access to the user dynamic network.
arch/tile: Enable more sophisticated IRQ model for 32-bit chips.
Move list types from <linux/list.h> to <linux/types.h>.
Add wait4() back to the set of <asm-generic/unistd.h> syscalls.
Revert adding some arch-specific signal syscalls to <linux/syscalls.h>.
arch/tile: Do not use GFP_KERNEL for dma_alloc_coherent(). Feedback from fujita.tomonori@lab.ntt.co.jp.
arch/tile: core support for Tilera 32-bit chips.
Fix up the "generic" unistd.h ABI to be more useful.
Diffstat (limited to 'arch/tile/lib/memmove_32.c')
-rw-r--r-- | arch/tile/lib/memmove_32.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/tile/lib/memmove_32.c b/arch/tile/lib/memmove_32.c new file mode 100644 index 0000000..fd615ae --- /dev/null +++ b/arch/tile/lib/memmove_32.c @@ -0,0 +1,63 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/module.h> + +void *memmove(void *dest, const void *src, size_t n) +{ + if ((const char *)src >= (char *)dest + n + || (char *)dest >= (const char *)src + n) { + /* We found no overlap, so let memcpy do all the heavy + * lifting (prefetching, etc.) + */ + return memcpy(dest, src, n); + } + + if (n != 0) { + const uint8_t *in; + uint8_t x; + uint8_t *out; + int stride; + + if (src < dest) { + /* copy backwards */ + in = (const uint8_t *)src + n - 1; + out = (uint8_t *)dest + n - 1; + stride = -1; + } else { + /* copy forwards */ + in = (const uint8_t *)src; + out = (uint8_t *)dest; + stride = 1; + } + + /* Manually software-pipeline this loop. */ + x = *in; + in += stride; + + while (--n != 0) { + *out = x; + out += stride; + x = *in; + in += stride; + } + + *out = x; + } + + return dest; +} +EXPORT_SYMBOL(memmove); |