Aren/haiku
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

* Fixup atomic calls; currently only minimally tested on __ARM_ARCH__ < 6

Browse Source 
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@38999 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Ithamar R. Adema 2010-10-18 12:10:16 +00:00
parent b8616583e4
commit 60beb9c01e
1 changed files with 22 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

41
src/system/libroot/os/arch/arm/atomic.S
View File

@ -120,20 +120,8 @@ miss4: ldrex r12, [r0]
bne miss4
bx lr
#else
/* disable interrupts, do the mov, and reenable */
mrs r2, cpsr
mov r12, r2
orr r2, r2, #(3<<6)
msr cpsr_c, r2
/* ints disabled, old cpsr state in r12 */
mov r3, r0
ldr r0, [r3]
str r1, [r3]
/* restore interrupts and exit */
msr cpsr_c, r12
mov r3, r0
swp r0, r1, [r3]
bx lr
#endif
FUNCTION_END(atomic_set)
@ -142,7 +130,7 @@ FUNCTION_END(atomic_set)
*/
FUNCTION(atomic_test_and_set):
#if __ARM_ARCH__ >= 6
/*miss5: ldrex r12, [r0] @ load from the address and mark it exclusive
miss5: ldrex r12, [r0] @ load from the address and mark it exclusive
cmp r12, r2 @ compare the value with the comperand(r2)
strexeq r3, r1, [r0] @ if they were equal, attempt to store the new value (r1)
bne differ @ if they were not equal jump to (differ) which clears the exclusive tag on the address and returns<
@ -150,16 +138,31 @@ FUNCTION(atomic_test_and_set):
beq miss5 @ go back to the start if it failed (0=success, 1=failure)
bne same @ if it succeeded, jump to (same) and return. there is no need to clrex if strex succeeded
differ: clrex @ clrex
same: mov r0, r12*/
same: mov r0, r12
#else
/* disable interrupts, and save state */
mrs r3, cpsr
mov r12, r3
orr r3, r3, #(3<<6)
msr cpsr_c, r3
mov r3, r0
ldr r0, [r3]
cmp r0, r2
streq r1, [r3]
/* restore interrupts and exit */
msr cpsr_c, r12
#endif
#warning TODO TODO TODO
bx lr
bx lr
FUNCTION_END(atomic_test_and_set)
/* int atomic_get(int *value)
*/
FUNCTION(atomic_get):
bx lr
mov r1, r0
swp r0, r0, [r1]
bx lr
FUNCTION_END(atomic_get)