treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / arch / alpha / oprofile / common.c
blob1b1259c7d7d132795e0141b1dbd1af229370bdf8
1 /**
2 * @file arch/alpha/oprofile/common.c
4 * @remark Copyright 2002 OProfile authors
5 * @remark Read the file COPYING
7 * @author Richard Henderson <rth@twiddle.net>
8 */
10 #include <linux/oprofile.h>
11 #include <linux/init.h>
12 #include <linux/smp.h>
13 #include <linux/errno.h>
14 #include <asm/ptrace.h>
15 #include <asm/special_insns.h>
17 #include "op_impl.h"
19 extern struct op_axp_model op_model_ev4 __attribute__((weak));
20 extern struct op_axp_model op_model_ev5 __attribute__((weak));
21 extern struct op_axp_model op_model_pca56 __attribute__((weak));
22 extern struct op_axp_model op_model_ev6 __attribute__((weak));
23 extern struct op_axp_model op_model_ev67 __attribute__((weak));
25 static struct op_axp_model *model;
27 extern void (*perf_irq)(unsigned long, struct pt_regs *);
28 static void (*save_perf_irq)(unsigned long, struct pt_regs *);
30 static struct op_counter_config ctr[20];
31 static struct op_system_config sys;
32 static struct op_register_config reg;
34 /* Called from do_entInt to handle the performance monitor interrupt. */
36 static void
37 op_handle_interrupt(unsigned long which, struct pt_regs *regs)
39 model->handle_interrupt(which, regs, ctr);
41 /* If the user has selected an interrupt frequency that is
42 not exactly the width of the counter, write a new value
43 into the counter such that it'll overflow after N more
44 events. */
45 if ((reg.need_reset >> which) & 1)
46 model->reset_ctr(&reg, which);
49 static int
50 op_axp_setup(void)
52 unsigned long i, e;
54 /* Install our interrupt handler into the existing hook. */
55 save_perf_irq = perf_irq;
56 perf_irq = op_handle_interrupt;
58 /* Compute the mask of enabled counters. */
59 for (i = e = 0; i < model->num_counters; ++i)
60 if (ctr[i].enabled)
61 e |= 1 << i;
62 reg.enable = e;
64 /* Pre-compute the values to stuff in the hardware registers. */
65 model->reg_setup(&reg, ctr, &sys);
67 /* Configure the registers on all cpus. */
68 smp_call_function(model->cpu_setup, &reg, 1);
69 model->cpu_setup(&reg);
70 return 0;
73 static void
74 op_axp_shutdown(void)
76 /* Remove our interrupt handler. We may be removing this module. */
77 perf_irq = save_perf_irq;
80 static void
81 op_axp_cpu_start(void *dummy)
83 wrperfmon(1, reg.enable);
86 static int
87 op_axp_start(void)
89 smp_call_function(op_axp_cpu_start, NULL, 1);
90 op_axp_cpu_start(NULL);
91 return 0;
94 static inline void
95 op_axp_cpu_stop(void *dummy)
97 /* Disable performance monitoring for all counters. */
98 wrperfmon(0, -1);
101 static void
102 op_axp_stop(void)
104 smp_call_function(op_axp_cpu_stop, NULL, 1);
105 op_axp_cpu_stop(NULL);
108 static int
109 op_axp_create_files(struct dentry *root)
111 int i;
113 for (i = 0; i < model->num_counters; ++i) {
114 struct dentry *dir;
115 char buf[4];
117 snprintf(buf, sizeof buf, "%d", i);
118 dir = oprofilefs_mkdir(root, buf);
120 oprofilefs_create_ulong(dir, "enabled", &ctr[i].enabled);
121 oprofilefs_create_ulong(dir, "event", &ctr[i].event);
122 oprofilefs_create_ulong(dir, "count", &ctr[i].count);
123 /* Dummies. */
124 oprofilefs_create_ulong(dir, "kernel", &ctr[i].kernel);
125 oprofilefs_create_ulong(dir, "user", &ctr[i].user);
126 oprofilefs_create_ulong(dir, "unit_mask", &ctr[i].unit_mask);
129 if (model->can_set_proc_mode) {
130 oprofilefs_create_ulong(root, "enable_pal",
131 &sys.enable_pal);
132 oprofilefs_create_ulong(root, "enable_kernel",
133 &sys.enable_kernel);
134 oprofilefs_create_ulong(root, "enable_user",
135 &sys.enable_user);
138 return 0;
141 int __init
142 oprofile_arch_init(struct oprofile_operations *ops)
144 struct op_axp_model *lmodel = NULL;
146 switch (implver()) {
147 case IMPLVER_EV4:
148 lmodel = &op_model_ev4;
149 break;
150 case IMPLVER_EV5:
151 /* 21164PC has a slightly different set of events.
152 Recognize the chip by the presence of the MAX insns. */
153 if (!amask(AMASK_MAX))
154 lmodel = &op_model_pca56;
155 else
156 lmodel = &op_model_ev5;
157 break;
158 case IMPLVER_EV6:
159 /* 21264A supports ProfileMe.
160 Recognize the chip by the presence of the CIX insns. */
161 if (!amask(AMASK_CIX))
162 lmodel = &op_model_ev67;
163 else
164 lmodel = &op_model_ev6;
165 break;
168 if (!lmodel)
169 return -ENODEV;
170 model = lmodel;
172 ops->create_files = op_axp_create_files;
173 ops->setup = op_axp_setup;
174 ops->shutdown = op_axp_shutdown;
175 ops->start = op_axp_start;
176 ops->stop = op_axp_stop;
177 ops->cpu_type = lmodel->cpu_type;
179 printk(KERN_INFO "oprofile: using %s performance monitoring.\n",
180 lmodel->cpu_type);
182 return 0;
186 void
187 oprofile_arch_exit(void)