Merge branch 'nfs-server-stable' of git://linux-nfs.org/~bfields/linux
[linux-2.6] / arch / x86 / oprofile / op_model_ppro.c
1 /**
2  * @file op_model_ppro.h
3  * pentium pro / P6 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/apic.h>
17 #include <asm/nmi.h>
18  
19 #include "op_x86_model.h"
20 #include "op_counter.h"
21
22 #define NUM_COUNTERS 2
23 #define NUM_CONTROLS 2
24
25 #define CTR_IS_RESERVED(msrs,c) (msrs->counters[(c)].addr ? 1 : 0)
26 #define CTR_READ(l,h,msrs,c) do {rdmsr(msrs->counters[(c)].addr, (l), (h));} while (0)
27 #define CTR_32BIT_WRITE(l,msrs,c)       \
28         do {wrmsr(msrs->counters[(c)].addr, -(u32)(l), 0);} while (0)
29 #define CTR_OVERFLOWED(n) (!((n) & (1U<<31)))
30
31 #define CTRL_IS_RESERVED(msrs,c) (msrs->controls[(c)].addr ? 1 : 0)
32 #define CTRL_READ(l,h,msrs,c) do {rdmsr((msrs->controls[(c)].addr), (l), (h));} while (0)
33 #define CTRL_WRITE(l,h,msrs,c) do {wrmsr((msrs->controls[(c)].addr), (l), (h));} while (0)
34 #define CTRL_SET_ACTIVE(n) (n |= (1<<22))
35 #define CTRL_SET_INACTIVE(n) (n &= ~(1<<22))
36 #define CTRL_CLEAR(x) (x &= (1<<21))
37 #define CTRL_SET_ENABLE(val) (val |= 1<<20)
38 #define CTRL_SET_USR(val,u) (val |= ((u & 1) << 16))
39 #define CTRL_SET_KERN(val,k) (val |= ((k & 1) << 17))
40 #define CTRL_SET_UM(val, m) (val |= (m << 8))
41 #define CTRL_SET_EVENT(val, e) (val |= e)
42
43 static unsigned long reset_value[NUM_COUNTERS];
44  
45 static void ppro_fill_in_addresses(struct op_msrs * const msrs)
46 {
47         int i;
48
49         for (i=0; i < NUM_COUNTERS; i++) {
50                 if (reserve_perfctr_nmi(MSR_P6_PERFCTR0 + i))
51                         msrs->counters[i].addr = MSR_P6_PERFCTR0 + i;
52                 else
53                         msrs->counters[i].addr = 0;
54         }
55         
56         for (i=0; i < NUM_CONTROLS; i++) {
57                 if (reserve_evntsel_nmi(MSR_P6_EVNTSEL0 + i))
58                         msrs->controls[i].addr = MSR_P6_EVNTSEL0 + i;
59                 else
60                         msrs->controls[i].addr = 0;
61         }
62 }
63
64
65 static void ppro_setup_ctrs(struct op_msrs const * const msrs)
66 {
67         unsigned int low, high;
68         int i;
69
70         /* clear all counters */
71         for (i = 0 ; i < NUM_CONTROLS; ++i) {
72                 if (unlikely(!CTRL_IS_RESERVED(msrs,i)))
73                         continue;
74                 CTRL_READ(low, high, msrs, i);
75                 CTRL_CLEAR(low);
76                 CTRL_WRITE(low, high, msrs, i);
77         }
78         
79         /* avoid a false detection of ctr overflows in NMI handler */
80         for (i = 0; i < NUM_COUNTERS; ++i) {
81                 if (unlikely(!CTR_IS_RESERVED(msrs,i)))
82                         continue;
83                 CTR_32BIT_WRITE(1, msrs, i);
84         }
85
86         /* enable active counters */
87         for (i = 0; i < NUM_COUNTERS; ++i) {
88                 if ((counter_config[i].enabled) && (CTR_IS_RESERVED(msrs,i))) {
89                         reset_value[i] = counter_config[i].count;
90
91                         CTR_32BIT_WRITE(counter_config[i].count, msrs, i);
92
93                         CTRL_READ(low, high, msrs, i);
94                         CTRL_CLEAR(low);
95                         CTRL_SET_ENABLE(low);
96                         CTRL_SET_USR(low, counter_config[i].user);
97                         CTRL_SET_KERN(low, counter_config[i].kernel);
98                         CTRL_SET_UM(low, counter_config[i].unit_mask);
99                         CTRL_SET_EVENT(low, counter_config[i].event);
100                         CTRL_WRITE(low, high, msrs, i);
101                 } else {
102                         reset_value[i] = 0;
103                 }
104         }
105 }
106
107  
108 static int ppro_check_ctrs(struct pt_regs * const regs,
109                            struct op_msrs const * const msrs)
110 {
111         unsigned int low, high;
112         int i;
113  
114         for (i = 0 ; i < NUM_COUNTERS; ++i) {
115                 if (!reset_value[i])
116                         continue;
117                 CTR_READ(low, high, msrs, i);
118                 if (CTR_OVERFLOWED(low)) {
119                         oprofile_add_sample(regs, i);
120                         CTR_32BIT_WRITE(reset_value[i], msrs, i);
121                 }
122         }
123
124         /* Only P6 based Pentium M need to re-unmask the apic vector but it
125          * doesn't hurt other P6 variant */
126         apic_write(APIC_LVTPC, apic_read(APIC_LVTPC) & ~APIC_LVT_MASKED);
127
128         /* We can't work out if we really handled an interrupt. We
129          * might have caught a *second* counter just after overflowing
130          * the interrupt for this counter then arrives
131          * and we don't find a counter that's overflowed, so we
132          * would return 0 and get dazed + confused. Instead we always
133          * assume we found an overflow. This sucks.
134          */
135         return 1;
136 }
137
138  
139 static void ppro_start(struct op_msrs const * const msrs)
140 {
141         unsigned int low,high;
142         int i;
143
144         for (i = 0; i < NUM_COUNTERS; ++i) {
145                 if (reset_value[i]) {
146                         CTRL_READ(low, high, msrs, i);
147                         CTRL_SET_ACTIVE(low);
148                         CTRL_WRITE(low, high, msrs, i);
149                 }
150         }
151 }
152
153
154 static void ppro_stop(struct op_msrs const * const msrs)
155 {
156         unsigned int low,high;
157         int i;
158
159         for (i = 0; i < NUM_COUNTERS; ++i) {
160                 if (!reset_value[i])
161                         continue;
162                 CTRL_READ(low, high, msrs, i);
163                 CTRL_SET_INACTIVE(low);
164                 CTRL_WRITE(low, high, msrs, i);
165         }
166 }
167
168 static void ppro_shutdown(struct op_msrs const * const msrs)
169 {
170         int i;
171
172         for (i = 0 ; i < NUM_COUNTERS ; ++i) {
173                 if (CTR_IS_RESERVED(msrs,i))
174                         release_perfctr_nmi(MSR_P6_PERFCTR0 + i);
175         }
176         for (i = 0 ; i < NUM_CONTROLS ; ++i) {
177                 if (CTRL_IS_RESERVED(msrs,i))
178                         release_evntsel_nmi(MSR_P6_EVNTSEL0 + i);
179         }
180 }
181
182
183 struct op_x86_model_spec const op_ppro_spec = {
184         .num_counters = NUM_COUNTERS,
185         .num_controls = NUM_CONTROLS,
186         .fill_in_addresses = &ppro_fill_in_addresses,
187         .setup_ctrs = &ppro_setup_ctrs,
188         .check_ctrs = &ppro_check_ctrs,
189         .start = &ppro_start,
190         .stop = &ppro_stop,
191         .shutdown = &ppro_shutdown
192 };