Mirrors_Framework/nuttx
1
0
Fork 0
mirror of https://github.com/apache/nuttx.git synced 2026-05-13 02:18:38 +08:00
Code Issues Actions 1 Packages Projects Releases Wiki Activity

spinlock: fix stxr instruction status register requirement

Browse Source 
error: unpredictable STXR instruction, status is also a source
   99 |     "stxr     %w0, %1, [%2] \n"
      |      ^
<inline asm>:5:10: note: instantiated into assembly here
    5 | stxr     w10, x10, [x9]
Using w0 to pass the result can cause the "status register is also a source" problem, resulting in unpredictable behavior.

Signed-off-by: wangmingrong1 <wangmingrong1@xiaomi.com>
This commit is contained in:
wangmingrong1
2025-05-09 12:45:53 +08:00
committed by Xiang Xiao
parent 68a1774eae
commit c6a528ef11
1 changed files with 7 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files
arch/arm64/include/spinlock.h
+7 -6
View File
@@ -91,18 +91,19 @@ typedef uint64_t spinlock_t;
static inline_function spinlock_t up_testset(volatile spinlock_t *lock)
{
spinlock_t ret = SP_LOCKED;
spinlock_t tmp = 0;
__asm__ __volatile__
(
"1: \n"
"ldaxr %0, [%2] \n"
"cmp %0, %1 \n"
"ldaxr %0, [%3] \n"
"cmp %0, %2 \n"
"beq 2f \n"
"stxr %w0, %1, [%2] \n"
"cbnz %w0, 1b \n"
"stxr %w1, %2, [%3] \n"
"cbnz %w1, 1b \n"
"2: \n"
: "+r" (ret)
: "r" (SP_LOCKED), "r" (lock)
: "=r" (ret)
: "r" (tmp), "r" (SP_LOCKED), "r" (lock)
: "memory"
);