x86 idle: clarify AMD erratum 400 workaround
authorLen Brown <len.brown@intel.com>
Fri, 1 Apr 2011 20:59:53 +0000 (16:59 -0400)
committerLen Brown <len.brown@intel.com>
Sun, 29 May 2011 07:38:57 +0000 (03:38 -0400)
The workaround for AMD erratum 400 uses the term "c1e" falsely suggesting:
1. Intel C1E is somehow involved
2. All AMD processors with C1E are involved

Use the string "amd_c1e" instead of simply "c1e" to clarify that
this workaround is specific to AMD's version of C1E.
Use the string "e400" to clarify that the workaround is specific
to AMD processors with Erratum 400.

This patch is text-substitution only, with no functional change.

cc: x86@kernel.org
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>
arch/x86/include/asm/acpi.h
arch/x86/include/asm/idle.h
arch/x86/include/asm/processor.h
arch/x86/kernel/cpu/common.c
arch/x86/kernel/process.c
arch/x86/kernel/smpboot.c
drivers/acpi/processor_idle.c

index 4ea15ca89b2b1110c4d0f6032d8ddee9256fb0b4..52fd57f95c50078e9dc06536f9b5b7a39d9e0d51 100644 (file)
@@ -138,7 +138,7 @@ static inline unsigned int acpi_processor_cstate_check(unsigned int max_cstate)
            boot_cpu_data.x86_model <= 0x05 &&
            boot_cpu_data.x86_mask < 0x0A)
                return 1;
-       else if (c1e_detected)
+       else if (amd_e400_c1e_detected)
                return 1;
        else
                return max_cstate;
index 38d87379e270596635ff569242c54ff71ad3ce69..f49253d75710e90bd31a86956d941b0cfb289940 100644 (file)
@@ -16,6 +16,6 @@ static inline void enter_idle(void) { }
 static inline void exit_idle(void) { }
 #endif /* CONFIG_X86_64 */
 
-void c1e_remove_cpu(int cpu);
+void amd_e400_remove_cpu(int cpu);
 
 #endif /* _ASM_X86_IDLE_H */
index 45636cefa186b427f558d98b7257a0f00dd405ec..b9c03fb3369a56a1ba7594e29c1d77885de016f0 100644 (file)
@@ -758,10 +758,10 @@ static inline void __sti_mwait(unsigned long eax, unsigned long ecx)
 extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx);
 
 extern void select_idle_routine(const struct cpuinfo_x86 *c);
-extern void init_c1e_mask(void);
+extern void init_amd_e400_c1e_mask(void);
 
 extern unsigned long           boot_option_idle_override;
-extern bool                    c1e_detected;
+extern bool                    amd_e400_c1e_detected;
 
 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
                         IDLE_POLL, IDLE_FORCE_MWAIT};
index 1d59834396bdc145c630e671d1bccd7769689a88..745a602f204f70054cb81fe5a3815f16d9c83258 100644 (file)
@@ -887,7 +887,7 @@ static void vgetcpu_set_mode(void)
 void __init identify_boot_cpu(void)
 {
        identify_cpu(&boot_cpu_data);
-       init_c1e_mask();
+       init_amd_e400_c1e_mask();
 #ifdef CONFIG_X86_32
        sysenter_setup();
        enable_sep_cpu();
index ff4554198981217172f8db1a43cac5228f1ff41d..2efbfb712fb7807a74c1377d2f667a165e60a6c8 100644 (file)
@@ -538,45 +538,45 @@ int mwait_usable(const struct cpuinfo_x86 *c)
        return (edx & MWAIT_EDX_C1);
 }
 
-bool c1e_detected;
-EXPORT_SYMBOL(c1e_detected);
+bool amd_e400_c1e_detected;
+EXPORT_SYMBOL(amd_e400_c1e_detected);
 
-static cpumask_var_t c1e_mask;
+static cpumask_var_t amd_e400_c1e_mask;
 
-void c1e_remove_cpu(int cpu)
+void amd_e400_remove_cpu(int cpu)
 {
-       if (c1e_mask != NULL)
-               cpumask_clear_cpu(cpu, c1e_mask);
+       if (amd_e400_c1e_mask != NULL)
+               cpumask_clear_cpu(cpu, amd_e400_c1e_mask);
 }
 
 /*
- * C1E aware idle routine. We check for C1E active in the interrupt
+ * AMD Erratum 400 aware idle routine. We check for C1E active in the interrupt
  * pending message MSR. If we detect C1E, then we handle it the same
  * way as C3 power states (local apic timer and TSC stop)
  */
-static void c1e_idle(void)
+static void amd_e400_idle(void)
 {
        if (need_resched())
                return;
 
-       if (!c1e_detected) {
+       if (!amd_e400_c1e_detected) {
                u32 lo, hi;
 
                rdmsr(MSR_K8_INT_PENDING_MSG, lo, hi);
 
                if (lo & K8_INTP_C1E_ACTIVE_MASK) {
-                       c1e_detected = true;
+                       amd_e400_c1e_detected = true;
                        if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
                                mark_tsc_unstable("TSC halt in AMD C1E");
                        printk(KERN_INFO "System has AMD C1E enabled\n");
                }
        }
 
-       if (c1e_detected) {
+       if (amd_e400_c1e_detected) {
                int cpu = smp_processor_id();
 
-               if (!cpumask_test_cpu(cpu, c1e_mask)) {
-                       cpumask_set_cpu(cpu, c1e_mask);
+               if (!cpumask_test_cpu(cpu, amd_e400_c1e_mask)) {
+                       cpumask_set_cpu(cpu, amd_e400_c1e_mask);
                        /*
                         * Force broadcast so ACPI can not interfere.
                         */
@@ -619,17 +619,17 @@ void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c)
                pm_idle = mwait_idle;
        } else if (cpu_has_amd_erratum(amd_erratum_400)) {
                /* E400: APIC timer interrupt does not wake up CPU from C1e */
-               printk(KERN_INFO "using C1E aware idle routine\n");
-               pm_idle = c1e_idle;
+               printk(KERN_INFO "using AMD E400 aware idle routine\n");
+               pm_idle = amd_e400_idle;
        } else
                pm_idle = default_idle;
 }
 
-void __init init_c1e_mask(void)
+void __init init_amd_e400_c1e_mask(void)
 {
-       /* If we're using c1e_idle, we need to allocate c1e_mask. */
-       if (pm_idle == c1e_idle)
-               zalloc_cpumask_var(&c1e_mask, GFP_KERNEL);
+       /* If we're using amd_e400_idle, we need to allocate amd_e400_c1e_mask. */
+       if (pm_idle == amd_e400_idle)
+               zalloc_cpumask_var(&amd_e400_c1e_mask, GFP_KERNEL);
 }
 
 static int __init idle_setup(char *str)
index 08776a953487f826dad0acc84b5b6e35f6272387..2c33633595cc093cc959733a29ff1be6face10d4 100644 (file)
@@ -1379,7 +1379,7 @@ void play_dead_common(void)
 {
        idle_task_exit();
        reset_lazy_tlbstate();
-       c1e_remove_cpu(raw_smp_processor_id());
+       amd_e400_remove_cpu(raw_smp_processor_id());
 
        mb();
        /* Ack it */
index d615b7d69bcaff7c29847b2eee37e4b08876dc90..431ab11c8c1b6736aec984754c9f6002d3542ad8 100644 (file)
@@ -161,7 +161,7 @@ static void lapic_timer_check_state(int state, struct acpi_processor *pr,
        if (cpu_has(&cpu_data(pr->id), X86_FEATURE_ARAT))
                return;
 
-       if (c1e_detected)
+       if (amd_e400_c1e_detected)
                type = ACPI_STATE_C1;
 
        /*