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-rw-r--r--arch/x86/kernel/process.c50
1 files changed, 9 insertions, 41 deletions
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index cbcf013a0ec6..57d1868a86aa 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -301,8 +301,9 @@ EXPORT_SYMBOL(kernel_thread);
301/* 301/*
302 * sys_execve() executes a new program. 302 * sys_execve() executes a new program.
303 */ 303 */
304long sys_execve(char __user *name, char __user * __user *argv, 304long sys_execve(const char __user *name,
305 char __user * __user *envp, struct pt_regs *regs) 305 const char __user *const __user *argv,
306 const char __user *const __user *envp, struct pt_regs *regs)
306{ 307{
307 long error; 308 long error;
308 char *filename; 309 char *filename;
@@ -526,44 +527,10 @@ static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c)
526 return (edx & MWAIT_EDX_C1); 527 return (edx & MWAIT_EDX_C1);
527} 528}
528 529
529/* 530bool c1e_detected;
530 * Check for AMD CPUs, where APIC timer interrupt does not wake up CPU from C1e. 531EXPORT_SYMBOL(c1e_detected);
531 * For more information see
532 * - Erratum #400 for NPT family 0xf and family 0x10 CPUs
533 * - Erratum #365 for family 0x11 (not affected because C1e not in use)
534 */
535static int __cpuinit check_c1e_idle(const struct cpuinfo_x86 *c)
536{
537 u64 val;
538 if (c->x86_vendor != X86_VENDOR_AMD)
539 goto no_c1e_idle;
540
541 /* Family 0x0f models < rev F do not have C1E */
542 if (c->x86 == 0x0F && c->x86_model >= 0x40)
543 return 1;
544
545 if (c->x86 == 0x10) {
546 /*
547 * check OSVW bit for CPUs that are not affected
548 * by erratum #400
549 */
550 if (cpu_has(c, X86_FEATURE_OSVW)) {
551 rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, val);
552 if (val >= 2) {
553 rdmsrl(MSR_AMD64_OSVW_STATUS, val);
554 if (!(val & BIT(1)))
555 goto no_c1e_idle;
556 }
557 }
558 return 1;
559 }
560
561no_c1e_idle:
562 return 0;
563}
564 532
565static cpumask_var_t c1e_mask; 533static cpumask_var_t c1e_mask;
566static int c1e_detected;
567 534
568void c1e_remove_cpu(int cpu) 535void c1e_remove_cpu(int cpu)
569{ 536{
@@ -585,12 +552,12 @@ static void c1e_idle(void)
585 u32 lo, hi; 552 u32 lo, hi;
586 553
587 rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi); 554 rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi);
555
588 if (lo & K8_INTP_C1E_ACTIVE_MASK) { 556 if (lo & K8_INTP_C1E_ACTIVE_MASK) {
589 c1e_detected = 1; 557 c1e_detected = true;
590 if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC)) 558 if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
591 mark_tsc_unstable("TSC halt in AMD C1E"); 559 mark_tsc_unstable("TSC halt in AMD C1E");
592 printk(KERN_INFO "System has AMD C1E enabled\n"); 560 printk(KERN_INFO "System has AMD C1E enabled\n");
593 set_cpu_cap(&boot_cpu_data, X86_FEATURE_AMDC1E);
594 } 561 }
595 } 562 }
596 563
@@ -639,7 +606,8 @@ void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
639 */ 606 */
640 printk(KERN_INFO "using mwait in idle threads.\n"); 607 printk(KERN_INFO "using mwait in idle threads.\n");
641 pm_idle = mwait_idle; 608 pm_idle = mwait_idle;
642 } else if (check_c1e_idle(c)) { 609 } else if (cpu_has_amd_erratum(amd_erratum_400)) {
610 /* E400: APIC timer interrupt does not wake up CPU from C1e */
643 printk(KERN_INFO "using C1E aware idle routine\n"); 611 printk(KERN_INFO "using C1E aware idle routine\n");
644 pm_idle = c1e_idle; 612 pm_idle = c1e_idle;
645 } else 613 } else