diff options
| -rw-r--r-- | arch/ia64/kernel/ptrace.c | 6 | ||||
| -rw-r--r-- | arch/ia64/kernel/traps.c | 11 | ||||
| -rw-r--r-- | include/asm-ia64/processor.h | 10 |
3 files changed, 24 insertions, 3 deletions
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c index 08c8a5eb25a..575a8f657b3 100644 --- a/arch/ia64/kernel/ptrace.c +++ b/arch/ia64/kernel/ptrace.c @@ -635,11 +635,17 @@ ia64_flush_fph (struct task_struct *task) { struct ia64_psr *psr = ia64_psr(ia64_task_regs(task)); + /* + * Prevent migrating this task while + * we're fiddling with the FPU state + */ + preempt_disable(); if (ia64_is_local_fpu_owner(task) && psr->mfh) { psr->mfh = 0; task->thread.flags |= IA64_THREAD_FPH_VALID; ia64_save_fpu(&task->thread.fph[0]); } + preempt_enable(); } /* diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c index 9bad6652d53..1861173bd4f 100644 --- a/arch/ia64/kernel/traps.c +++ b/arch/ia64/kernel/traps.c @@ -220,13 +220,21 @@ disabled_fph_fault (struct pt_regs *regs) /* first, grant user-level access to fph partition: */ psr->dfh = 0; + + /* + * Make sure that no other task gets in on this processor + * while we're claiming the FPU + */ + preempt_disable(); #ifndef CONFIG_SMP { struct task_struct *fpu_owner = (struct task_struct *)ia64_get_kr(IA64_KR_FPU_OWNER); - if (ia64_is_local_fpu_owner(current)) + if (ia64_is_local_fpu_owner(current)) { + preempt_enable_no_resched(); return; + } if (fpu_owner) ia64_flush_fph(fpu_owner); @@ -244,6 +252,7 @@ disabled_fph_fault (struct pt_regs *regs) */ psr->mfh = 1; } + preempt_enable_no_resched(); } static inline int diff --git a/include/asm-ia64/processor.h b/include/asm-ia64/processor.h index 9e1ba8b7fb6..91bbd1f2246 100644 --- a/include/asm-ia64/processor.h +++ b/include/asm-ia64/processor.h @@ -403,7 +403,10 @@ extern void ia64_setreg_unknown_kr (void); * task_struct at this point. */ -/* Return TRUE if task T owns the fph partition of the CPU we're running on. */ +/* + * Return TRUE if task T owns the fph partition of the CPU we're running on. + * Must be called from code that has preemption disabled. + */ #define ia64_is_local_fpu_owner(t) \ ({ \ struct task_struct *__ia64_islfo_task = (t); \ @@ -411,7 +414,10 @@ extern void ia64_setreg_unknown_kr (void); && __ia64_islfo_task == (struct task_struct *) ia64_get_kr(IA64_KR_FPU_OWNER)); \ }) -/* Mark task T as owning the fph partition of the CPU we're running on. */ +/* + * Mark task T as owning the fph partition of the CPU we're running on. + * Must be called from code that has preemption disabled. + */ #define ia64_set_local_fpu_owner(t) do { \ struct task_struct *__ia64_slfo_task = (t); \ __ia64_slfo_task->thread.last_fph_cpu = smp_processor_id(); \ |