arch/i386/oprofile/op_model_athlon.c

   1 /**
   2  * @file op_model_athlon.h
   3  * athlon / K7 model-specific MSR operations
   4  *
   5  * @remark Copyright 2002 OProfile authors
   6  * @remark Read the file COPYING
   7  *
   8  * @author John Levon
   9  * @author Philippe Elie
  10  * @author Graydon Hoare
  11  */
  12
  13 #include <linux/oprofile.h>
  14 #include <asm/ptrace.h>
  15 #include <asm/msr.h>
  16 #include <asm/nmi.h>
  17
  18 #include "op_x86_model.h"
  19 #include "op_counter.h"
  20
  21 #define NUM_COUNTERS 4
  22 #define NUM_CONTROLS 4
  23
  24 #define CTR_READ(l,h,msrs,c) do {rdmsr(msrs->counters[(c)].addr, (l), (h));} while (0)
  25 #define CTR_WRITE(l,msrs,c) do {wrmsr(msrs->counters[(c)].addr, -(unsigned int)(l), -1);} while (0)
  26 #define CTR_OVERFLOWED(n) (!((n) & (1U<<31)))
  27
  28 #define CTRL_READ(l,h,msrs,c) do {rdmsr(msrs->controls[(c)].addr, (l), (h));} while (0)
  29 #define CTRL_WRITE(l,h,msrs,c) do {wrmsr(msrs->controls[(c)].addr, (l), (h));} while (0)
  30 #define CTRL_SET_ACTIVE(n) (n |= (1<<22))
  31 #define CTRL_SET_INACTIVE(n) (n &= ~(1<<22))
  32 #define CTRL_CLEAR(x) (x &= (1<<21))
  33 #define CTRL_SET_ENABLE(val) (val |= 1<<20)
  34 #define CTRL_SET_USR(val,u) (val |= ((u & 1) << 16))
  35 #define CTRL_SET_KERN(val,k) (val |= ((k & 1) << 17))
  36 #define CTRL_SET_UM(val, m) (val |= (m << 8))
  37 #define CTRL_SET_EVENT(val, e) (val |= e)
  38
  39 static unsigned long reset_value[NUM_COUNTERS];
  40
  41 static void athlon_fill_in_addresses(struct op_msrs * const msrs)
  42 {
  43         msrs->counters[0].addr = MSR_K7_PERFCTR0;
  44         msrs->counters[1].addr = MSR_K7_PERFCTR1;
  45         msrs->counters[2].addr = MSR_K7_PERFCTR2;
  46         msrs->counters[3].addr = MSR_K7_PERFCTR3;
  47
  48         msrs->controls[0].addr = MSR_K7_EVNTSEL0;
  49         msrs->controls[1].addr = MSR_K7_EVNTSEL1;
  50         msrs->controls[2].addr = MSR_K7_EVNTSEL2;
  51         msrs->controls[3].addr = MSR_K7_EVNTSEL3;
  52 }
  53
  54
  55 static void athlon_setup_ctrs(struct op_msrs const * const msrs)
  56 {
  57         unsigned int low, high;
  58         int i;
  59
  60         /* clear all counters */
  61         for (i = 0 ; i < NUM_CONTROLS; ++i) {
  62                 CTRL_READ(low, high, msrs, i);
  63                 CTRL_CLEAR(low);
  64                 CTRL_WRITE(low, high, msrs, i);
  65         }
  66
  67         /* avoid a false detection of ctr overflows in NMI handler */
  68         for (i = 0; i < NUM_COUNTERS; ++i) {
  69                 CTR_WRITE(1, msrs, i);
  70         }
  71
  72         /* enable active counters */
  73         for (i = 0; i < NUM_COUNTERS; ++i) {
  74                 if (counter_config[i].enabled) {
  75                         reset_value[i] = counter_config[i].count;
  76
  77                         CTR_WRITE(counter_config[i].count, msrs, i);
  78
  79                         CTRL_READ(low, high, msrs, i);
  80                         CTRL_CLEAR(low);
  81                         CTRL_SET_ENABLE(low);
  82                         CTRL_SET_USR(low, counter_config[i].user);
  83                         CTRL_SET_KERN(low, counter_config[i].kernel);
  84                         CTRL_SET_UM(low, counter_config[i].unit_mask);
  85                         CTRL_SET_EVENT(low, counter_config[i].event);
  86                         CTRL_WRITE(low, high, msrs, i);
  87                 } else {
  88                         reset_value[i] = 0;
  89                 }
  90         }
  91 }
  92
  93
  94 static int athlon_check_ctrs(struct pt_regs * const regs,
  95                              struct op_msrs const * const msrs)
  96 {
  97         unsigned int low, high;
  98         int i;
  99
 100         for (i = 0 ; i < NUM_COUNTERS; ++i) {
 101                 CTR_READ(low, high, msrs, i);
 102                 if (CTR_OVERFLOWED(low)) {
 103                         oprofile_add_sample(regs, i);
 104                         CTR_WRITE(reset_value[i], msrs, i);
 105                 }
 106         }
 107
 108         /* See op_model_ppro.c */
 109         return 1;
 110 }
 111
 112
 113 static void athlon_start(struct op_msrs const * const msrs)
 114 {
 115         unsigned int low, high;
 116         int i;
 117         for (i = 0 ; i < NUM_COUNTERS ; ++i) {
 118                 if (reset_value[i]) {
 119                         CTRL_READ(low, high, msrs, i);
 120                         CTRL_SET_ACTIVE(low);
 121                         CTRL_WRITE(low, high, msrs, i);
 122                 }
 123         }
 124 }
 125
 126
 127 static void athlon_stop(struct op_msrs const * const msrs)
 128 {
 129         unsigned int low,high;
 130         int i;
 131
 132         /* Subtle: stop on all counters to avoid race with
 133          * setting our pm callback */
 134         for (i = 0 ; i < NUM_COUNTERS ; ++i) {
 135                 CTRL_READ(low, high, msrs, i);
 136                 CTRL_SET_INACTIVE(low);
 137                 CTRL_WRITE(low, high, msrs, i);
 138         }
 139 }
 140
 141
 142 struct op_x86_model_spec const op_athlon_spec = {
 143         .num_counters = NUM_COUNTERS,
 144         .num_controls = NUM_CONTROLS,
 145         .fill_in_addresses = &athlon_fill_in_addresses,
 146         .setup_ctrs = &athlon_setup_ctrs,
 147         .check_ctrs = &athlon_check_ctrs,
 148         .start = &athlon_start,
 149         .stop = &athlon_stop
 150 };