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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/tile/lib/memset_32.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/tile/lib/memset_32.c')
-rw-r--r-- | kernel/arch/tile/lib/memset_32.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/kernel/arch/tile/lib/memset_32.c b/kernel/arch/tile/lib/memset_32.c new file mode 100644 index 000000000..2042bfe65 --- /dev/null +++ b/kernel/arch/tile/lib/memset_32.c @@ -0,0 +1,143 @@ +/* + * 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> +#include <arch/chip.h> + +void *memset(void *s, int c, size_t n) +{ + uint32_t *out32; + int n32; + uint32_t v16, v32; + uint8_t *out8 = s; + int to_align32; + + /* Experimentation shows that a trivial tight loop is a win up until + * around a size of 20, where writing a word at a time starts to win. + */ +#define BYTE_CUTOFF 20 + +#if BYTE_CUTOFF < 3 + /* This must be at least at least this big, or some code later + * on doesn't work. + */ +#error "BYTE_CUTOFF is too small" +#endif + + if (n < BYTE_CUTOFF) { + /* Strangely, this turns out to be the tightest way to + * write this loop. + */ + if (n != 0) { + do { + /* Strangely, combining these into one line + * performs worse. + */ + *out8 = c; + out8++; + } while (--n != 0); + } + + return s; + } + + /* Align 'out8'. We know n >= 3 so this won't write past the end. */ + while (((uintptr_t) out8 & 3) != 0) { + *out8++ = c; + --n; + } + + /* Align 'n'. */ + while (n & 3) + out8[--n] = c; + + out32 = (uint32_t *) out8; + n32 = n >> 2; + + /* Tile input byte out to 32 bits. */ + v16 = __insn_intlb(c, c); + v32 = __insn_intlh(v16, v16); + + /* This must be at least 8 or the following loop doesn't work. */ +#define CACHE_LINE_SIZE_IN_WORDS (CHIP_L2_LINE_SIZE() / 4) + + /* Determine how many words we need to emit before the 'out32' + * pointer becomes aligned modulo the cache line size. + */ + to_align32 = + (-((uintptr_t)out32 >> 2)) & (CACHE_LINE_SIZE_IN_WORDS - 1); + + /* Only bother aligning and using wh64 if there is at least + * one full cache line to process. This check also prevents + * overrunning the end of the buffer with alignment words. + */ + if (to_align32 <= n32 - CACHE_LINE_SIZE_IN_WORDS) { + int lines_left; + + /* Align out32 mod the cache line size so we can use wh64. */ + n32 -= to_align32; + for (; to_align32 != 0; to_align32--) { + *out32 = v32; + out32++; + } + + /* Use unsigned divide to turn this into a right shift. */ + lines_left = (unsigned)n32 / CACHE_LINE_SIZE_IN_WORDS; + + do { + /* Only wh64 a few lines at a time, so we don't + * exceed the maximum number of victim lines. + */ + int x = ((lines_left < CHIP_MAX_OUTSTANDING_VICTIMS()) + ? lines_left + : CHIP_MAX_OUTSTANDING_VICTIMS()); + uint32_t *wh = out32; + int i = x; + int j; + + lines_left -= x; + + do { + __insn_wh64(wh); + wh += CACHE_LINE_SIZE_IN_WORDS; + } while (--i); + + for (j = x * (CACHE_LINE_SIZE_IN_WORDS / 4); + j != 0; j--) { + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + *out32++ = v32; + } + } while (lines_left != 0); + + /* We processed all full lines above, so only this many + * words remain to be processed. + */ + n32 &= CACHE_LINE_SIZE_IN_WORDS - 1; + } + + /* Now handle any leftover values. */ + if (n32 != 0) { + do { + *out32 = v32; + out32++; + } while (--n32 != 0); + } + + return s; +} +EXPORT_SYMBOL(memset); |