tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/* Slow paths of read/write spinlocks. */
2
3#include <linux/linkage.h>
4#include <asm/rwlock.h>
5#include <asm/alternative-asm.h>
6#include <asm/dwarf2.h>
7
8/* rdi: pointer to rwlock_t */
9ENTRY(__write_lock_failed)
10 CFI_STARTPROC
11 LOCK_PREFIX
12 addl $RW_LOCK_BIAS,(%rdi)
131: rep
14 nop
15 cmpl $RW_LOCK_BIAS,(%rdi)
16 jne 1b
17 LOCK_PREFIX
18 subl $RW_LOCK_BIAS,(%rdi)
19 jnz __write_lock_failed
20 ret
21 CFI_ENDPROC
22END(__write_lock_failed)
23
24/* rdi: pointer to rwlock_t */
25ENTRY(__read_lock_failed)
26 CFI_STARTPROC
27 LOCK_PREFIX
28 incl (%rdi)
291: rep
30 nop
31 cmpl $1,(%rdi)
32 js 1b
33 LOCK_PREFIX
34 decl (%rdi)
35 js __read_lock_failed
36 ret
37 CFI_ENDPROC
38END(__read_lock_failed)