diff options
Diffstat (limited to 'arch/x86/kernel/process_32.c')
| -rw-r--r-- | arch/x86/kernel/process_32.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 5cec8a75a4e..496ea3110aa 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -484,20 +484,13 @@ int set_tsc_mode(unsigned int val) return 0; } -static noinline void -__switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, - struct tss_struct *tss) +#ifdef CONFIG_X86_DS +static int update_debugctl(struct thread_struct *prev, + struct thread_struct *next, unsigned long debugctl) { - struct thread_struct *prev, *next; - unsigned long debugctl; - unsigned long ds_prev = 0, ds_next = 0; + unsigned long ds_prev = 0; + unsigned long ds_next = 0; - prev = &prev_p->thread; - next = &next_p->thread; - - debugctl = prev->debugctlmsr; - -#ifdef CONFIG_X86_DS if (prev->ds_ctx) ds_prev = (unsigned long)prev->ds_ctx->ds; if (next->ds_ctx) @@ -510,8 +503,28 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, update_debugctlmsr(0); wrmsr(MSR_IA32_DS_AREA, ds_next, 0); } + return debugctl; +} +#else +static int update_debugctl(struct thread_struct *prev, + struct thread_struct *next, unsigned long debugctl) +{ + return debugctl; +} #endif /* CONFIG_X86_DS */ +static noinline void +__switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, + struct tss_struct *tss) +{ + struct thread_struct *prev, *next; + unsigned long debugctl; + + prev = &prev_p->thread; + next = &next_p->thread; + + debugctl = update_debugctl(prev, next, prev->debugctlmsr); + if (next->debugctlmsr != debugctl) update_debugctlmsr(next->debugctlmsr); |