diff options
| author | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2016-11-11 14:37:51 +0100 |
|---|---|---|
| committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2016-11-18 07:30:34 +0100 |
| commit | d5e073cde70211b2471e4366be397370e9f6ce48 (patch) | |
| tree | 7ee1e3cad3dd7dfbb52475af7bacc61b216dc0e5 /c/src/lib/libcpu | |
| parent | score: Add Per_CPU_Control::Interrupt_frame (diff) | |
| download | rtems-d5e073cde70211b2471e4366be397370e9f6ce48.tar.bz2 | |
score: Allow interrupts during thread dispatch
Use a processor-specific interrupt frame during context switches in case
the executing thread is longer executes on the processor and the heir
thread is about to start execution. During this period we must not use
a thread stack for interrupt processing.
Update #2809.
Diffstat (limited to 'c/src/lib/libcpu')
| -rw-r--r-- | c/src/lib/libcpu/powerpc/new-exceptions/cpu_asm.S | 29 |
1 files changed, 17 insertions, 12 deletions
diff --git a/c/src/lib/libcpu/powerpc/new-exceptions/cpu_asm.S b/c/src/lib/libcpu/powerpc/new-exceptions/cpu_asm.S index 7f3c036cf6..e5b4fcdbcd 100644 --- a/c/src/lib/libcpu/powerpc/new-exceptions/cpu_asm.S +++ b/c/src/lib/libcpu/powerpc/new-exceptions/cpu_asm.S @@ -402,23 +402,30 @@ PROC (_CPU_Context_switch): #endif #ifdef RTEMS_SMP - /* The executing context no longer executes on this processor */ + /* + * The executing thread no longer executes on this processor. Switch + * the stack to the temporary interrupt stack of this processor. Mark + * the context of the executing thread as not executing. + */ msync + + GET_SELF_CPU_CONTROL r12 + addi r1, r12, PER_CPU_INTERRUPT_FRAME_AREA + CPU_INTERRUPT_FRAME_SIZE li r6, 0 stw r6, PPC_CONTEXT_OFFSET_IS_EXECUTING(r3) -check_is_executing: +.Lcheck_is_executing: /* Check the is executing indicator of the heir context */ addi r6, r5, PPC_CONTEXT_OFFSET_IS_EXECUTING lwarx r7, r0, r6 cmpwi r7, 0 - bne get_potential_new_heir + bne .Lget_potential_new_heir /* Try to update the is executing indicator of the heir context */ li r7, 1 stwcx. r7, r0, r6 - bne get_potential_new_heir + bne .Lget_potential_new_heir isync #endif @@ -537,22 +544,20 @@ PROC (_CPU_Context_restore): b restore_context #ifdef RTEMS_SMP -get_potential_new_heir: - - GET_SELF_CPU_CONTROL r6 +.Lget_potential_new_heir: /* We may have a new heir */ /* Read the executing and heir */ - lwz r7, PER_CPU_OFFSET_EXECUTING(r6) - lwz r8, PER_CPU_OFFSET_HEIR(r6) + lwz r7, PER_CPU_OFFSET_EXECUTING(r12) + lwz r8, PER_CPU_OFFSET_HEIR(r12) /* * Update the executing only if necessary to avoid cache line * monopolization. */ cmpw r7, r8 - beq check_is_executing + beq .Lcheck_is_executing /* Calculate the heir context pointer */ sub r7, r4, r7 @@ -560,7 +565,7 @@ get_potential_new_heir: clrrwi r5, r4, PPC_DEFAULT_CACHE_LINE_POWER /* Update the executing */ - stw r8, PER_CPU_OFFSET_EXECUTING(r6) + stw r8, PER_CPU_OFFSET_EXECUTING(r12) - b check_is_executing + b .Lcheck_is_executing #endif |