summaryrefslogtreecommitdiffstats
path: root/cpukit/score/cpu/i386/cpu_asm.S
diff options
context:
space:
mode:
authorSebastian Huber <sebastian.huber@embedded-brains.de>2014-05-08 10:11:13 +0200
committerSebastian Huber <sebastian.huber@embedded-brains.de>2014-05-08 13:02:40 +0200
commit11b05f11d4d6d61717e345d20f492977b95ab131 (patch)
tree5f5bd2a21ea205ea0700d44718de7fcac8234fe7 /cpukit/score/cpu/i386/cpu_asm.S
parentdoc: Use @dfn for glossary terms (diff)
downloadrtems-11b05f11d4d6d61717e345d20f492977b95ab131.tar.bz2
score: Fix CPU context usage on SMP
We must not alter the is executing indicator in _CPU_Context_Initialize() since this would cause an invalid state during a self restart. The is executing indicator must be valid at creation time since otherwise _Thread_Kill_zombies() uses an undefined value for not started threads. This could result in a system life lock.
Diffstat (limited to 'cpukit/score/cpu/i386/cpu_asm.S')
-rw-r--r--cpukit/score/cpu/i386/cpu_asm.S8
1 files changed, 4 insertions, 4 deletions
diff --git a/cpukit/score/cpu/i386/cpu_asm.S b/cpukit/score/cpu/i386/cpu_asm.S
index cc08312f33..9b395678b8 100644
--- a/cpukit/score/cpu/i386/cpu_asm.S
+++ b/cpukit/score/cpu/i386/cpu_asm.S
@@ -58,24 +58,24 @@ SYM (_CPU_Context_switch):
movl edi,REG_EDI(eax) /* save destination register */
#ifdef RTEMS_SMP
- /* Indicate that this context is no longer executing */
+ /* The executing context no longer executes on this processor */
movb $0, I386_CONTEXT_CONTROL_IS_EXECUTING_OFFSET(eax)
#endif
movl HEIRCONTEXT_ARG(esp),eax /* eax = heir threads context */
-restore:
#ifdef RTEMS_SMP
- /* Wait for context to stop execution if necessary */
+ /* Wait for heir context to stop execution */
1:
movb I386_CONTEXT_CONTROL_IS_EXECUTING_OFFSET(eax), bl
testb bl, bl
jne 1b
- /* Indicate that this context is executing */
+ /* The heir context executes now on this processor */
movb $1, I386_CONTEXT_CONTROL_IS_EXECUTING_OFFSET(eax)
#endif
+restore:
pushl REG_EFLAGS(eax) /* push eflags */
popf /* restore eflags */
movl REG_ESP(eax),esp /* restore stack pointer */