diff options
author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/sparc/lib/bitext.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/sparc/lib/bitext.c')
-rw-r--r-- | kernel/arch/sparc/lib/bitext.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/kernel/arch/sparc/lib/bitext.c b/kernel/arch/sparc/lib/bitext.c new file mode 100644 index 000000000..8ec4e9c02 --- /dev/null +++ b/kernel/arch/sparc/lib/bitext.c @@ -0,0 +1,127 @@ +/* + * bitext.c: kernel little helper (of bit shuffling variety). + * + * Copyright (C) 2002 Pete Zaitcev <zaitcev@yahoo.com> + * + * The algorithm to search a zero bit string is geared towards its application. + * We expect a couple of fixed sizes of requests, so a rotating counter, reset + * by align size, should provide fast enough search while maintaining low + * fragmentation. + */ + +#include <linux/string.h> +#include <linux/bitmap.h> + +#include <asm/bitext.h> + +/** + * bit_map_string_get - find and set a bit string in bit map. + * @t: the bit map. + * @len: requested string length + * @align: requested alignment + * + * Returns offset in the map or -1 if out of space. + * + * Not safe to call from an interrupt (uses spin_lock). + */ +int bit_map_string_get(struct bit_map *t, int len, int align) +{ + int offset, count; /* siamese twins */ + int off_new; + int align1; + int i, color; + + if (t->num_colors) { + /* align is overloaded to be the page color */ + color = align; + align = t->num_colors; + } else { + color = 0; + if (align == 0) + align = 1; + } + align1 = align - 1; + if ((align & align1) != 0) + BUG(); + if (align < 0 || align >= t->size) + BUG(); + if (len <= 0 || len > t->size) + BUG(); + color &= align1; + + spin_lock(&t->lock); + if (len < t->last_size) + offset = t->first_free; + else + offset = t->last_off & ~align1; + count = 0; + for (;;) { + off_new = find_next_zero_bit(t->map, t->size, offset); + off_new = ((off_new + align1) & ~align1) + color; + count += off_new - offset; + offset = off_new; + if (offset >= t->size) + offset = 0; + if (count + len > t->size) { + spin_unlock(&t->lock); +/* P3 */ printk(KERN_ERR + "bitmap out: size %d used %d off %d len %d align %d count %d\n", + t->size, t->used, offset, len, align, count); + return -1; + } + + if (offset + len > t->size) { + count += t->size - offset; + offset = 0; + continue; + } + + i = 0; + while (test_bit(offset + i, t->map) == 0) { + i++; + if (i == len) { + bitmap_set(t->map, offset, len); + if (offset == t->first_free) + t->first_free = find_next_zero_bit + (t->map, t->size, + t->first_free + len); + if ((t->last_off = offset + len) >= t->size) + t->last_off = 0; + t->used += len; + t->last_size = len; + spin_unlock(&t->lock); + return offset; + } + } + count += i + 1; + if ((offset += i + 1) >= t->size) + offset = 0; + } +} + +void bit_map_clear(struct bit_map *t, int offset, int len) +{ + int i; + + if (t->used < len) + BUG(); /* Much too late to do any good, but alas... */ + spin_lock(&t->lock); + for (i = 0; i < len; i++) { + if (test_bit(offset + i, t->map) == 0) + BUG(); + __clear_bit(offset + i, t->map); + } + if (offset < t->first_free) + t->first_free = offset; + t->used -= len; + spin_unlock(&t->lock); +} + +void bit_map_init(struct bit_map *t, unsigned long *map, int size) +{ + bitmap_zero(map, size); + memset(t, 0, sizeof *t); + spin_lock_init(&t->lock); + t->map = map; + t->size = size; +} |