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-rw-r--r--arch/i386/kernel/apic.c61
1 files changed, 6 insertions, 55 deletions
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index d8f94e78de8a..2d8c6ce1ecda 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -92,10 +92,6 @@ void __init apic_intr_init(void)
92/* Using APIC to generate smp_local_timer_interrupt? */ 92/* Using APIC to generate smp_local_timer_interrupt? */
93int using_apic_timer = 0; 93int using_apic_timer = 0;
94 94
95static DEFINE_PER_CPU(int, prof_multiplier) = 1;
96static DEFINE_PER_CPU(int, prof_old_multiplier) = 1;
97static DEFINE_PER_CPU(int, prof_counter) = 1;
98
99static int enabled_via_apicbase; 95static int enabled_via_apicbase;
100 96
101void enable_NMI_through_LVT0 (void * dummy) 97void enable_NMI_through_LVT0 (void * dummy)
@@ -1092,34 +1088,6 @@ void enable_APIC_timer(void)
1092 } 1088 }
1093} 1089}
1094 1090
1095/*
1096 * the frequency of the profiling timer can be changed
1097 * by writing a multiplier value into /proc/profile.
1098 */
1099int setup_profiling_timer(unsigned int multiplier)
1100{
1101 int i;
1102
1103 /*
1104 * Sanity check. [at least 500 APIC cycles should be
1105 * between APIC interrupts as a rule of thumb, to avoid
1106 * irqs flooding us]
1107 */
1108 if ( (!multiplier) || (calibration_result/multiplier < 500))
1109 return -EINVAL;
1110
1111 /*
1112 * Set the new multiplier for each CPU. CPUs don't start using the
1113 * new values until the next timer interrupt in which they do process
1114 * accounting. At that time they also adjust their APIC timers
1115 * accordingly.
1116 */
1117 for (i = 0; i < NR_CPUS; ++i)
1118 per_cpu(prof_multiplier, i) = multiplier;
1119
1120 return 0;
1121}
1122
1123#undef APIC_DIVISOR 1091#undef APIC_DIVISOR
1124 1092
1125/* 1093/*
@@ -1134,32 +1102,10 @@ int setup_profiling_timer(unsigned int multiplier)
1134 1102
1135inline void smp_local_timer_interrupt(struct pt_regs * regs) 1103inline void smp_local_timer_interrupt(struct pt_regs * regs)
1136{ 1104{
1137 int cpu = smp_processor_id();
1138
1139 profile_tick(CPU_PROFILING, regs); 1105 profile_tick(CPU_PROFILING, regs);
1140 if (--per_cpu(prof_counter, cpu) <= 0) {
1141 /*
1142 * The multiplier may have changed since the last time we got
1143 * to this point as a result of the user writing to
1144 * /proc/profile. In this case we need to adjust the APIC
1145 * timer accordingly.
1146 *
1147 * Interrupts are already masked off at this point.
1148 */
1149 per_cpu(prof_counter, cpu) = per_cpu(prof_multiplier, cpu);
1150 if (per_cpu(prof_counter, cpu) !=
1151 per_cpu(prof_old_multiplier, cpu)) {
1152 __setup_APIC_LVTT(
1153 calibration_result/
1154 per_cpu(prof_counter, cpu));
1155 per_cpu(prof_old_multiplier, cpu) =
1156 per_cpu(prof_counter, cpu);
1157 }
1158
1159#ifdef CONFIG_SMP 1106#ifdef CONFIG_SMP
1160 update_process_times(user_mode_vm(regs)); 1107 update_process_times(user_mode_vm(regs));
1161#endif 1108#endif
1162 }
1163 1109
1164 /* 1110 /*
1165 * We take the 'long' return path, and there every subsystem 1111 * We take the 'long' return path, and there every subsystem
@@ -1206,6 +1152,11 @@ fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
1206 irq_exit(); 1152 irq_exit();
1207} 1153}
1208 1154
1155int setup_profiling_timer(unsigned int multiplier)
1156{
1157 return -EINVAL;
1158}
1159
1209/* 1160/*
1210 * This interrupt should _never_ happen with our APIC/SMP architecture 1161 * This interrupt should _never_ happen with our APIC/SMP architecture
1211 */ 1162 */