Linux-2.6.12-rc2
[linux-2.6/kvm.git] / arch / ia64 / kernel / perfmon_default_smpl.c
blob965d29004555acdbe24538a49edaf7fd67e178f1
1 /*
2 * Copyright (C) 2002-2003 Hewlett-Packard Co
3 * Stephane Eranian <eranian@hpl.hp.com>
5 * This file implements the default sampling buffer format
6 * for the Linux/ia64 perfmon-2 subsystem.
7 */
8 #include <linux/kernel.h>
9 #include <linux/types.h>
10 #include <linux/module.h>
11 #include <linux/config.h>
12 #include <linux/init.h>
13 #include <asm/delay.h>
14 #include <linux/smp.h>
16 #include <asm/perfmon.h>
17 #include <asm/perfmon_default_smpl.h>
19 MODULE_AUTHOR("Stephane Eranian <eranian@hpl.hp.com>");
20 MODULE_DESCRIPTION("perfmon default sampling format");
21 MODULE_LICENSE("GPL");
23 MODULE_PARM(debug, "i");
24 MODULE_PARM_DESC(debug, "debug");
26 MODULE_PARM(debug_ovfl, "i");
27 MODULE_PARM_DESC(debug_ovfl, "debug ovfl");
30 #define DEFAULT_DEBUG 1
32 #ifdef DEFAULT_DEBUG
33 #define DPRINT(a) \
34 do { \
35 if (unlikely(debug >0)) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
36 } while (0)
38 #define DPRINT_ovfl(a) \
39 do { \
40 if (unlikely(debug_ovfl >0)) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
41 } while (0)
43 #else
44 #define DPRINT(a)
45 #define DPRINT_ovfl(a)
46 #endif
48 static int debug, debug_ovfl;
50 static int
51 default_validate(struct task_struct *task, unsigned int flags, int cpu, void *data)
53 pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t*)data;
54 int ret = 0;
56 if (data == NULL) {
57 DPRINT(("[%d] no argument passed\n", task->pid));
58 return -EINVAL;
61 DPRINT(("[%d] validate flags=0x%x CPU%d\n", task->pid, flags, cpu));
64 * must hold at least the buffer header + one minimally sized entry
66 if (arg->buf_size < PFM_DEFAULT_SMPL_MIN_BUF_SIZE) return -EINVAL;
68 DPRINT(("buf_size=%lu\n", arg->buf_size));
70 return ret;
73 static int
74 default_get_size(struct task_struct *task, unsigned int flags, int cpu, void *data, unsigned long *size)
76 pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t *)data;
79 * size has been validated in default_validate
81 *size = arg->buf_size;
83 return 0;
86 static int
87 default_init(struct task_struct *task, void *buf, unsigned int flags, int cpu, void *data)
89 pfm_default_smpl_hdr_t *hdr;
90 pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t *)data;
92 hdr = (pfm_default_smpl_hdr_t *)buf;
94 hdr->hdr_version = PFM_DEFAULT_SMPL_VERSION;
95 hdr->hdr_buf_size = arg->buf_size;
96 hdr->hdr_cur_offs = sizeof(*hdr);
97 hdr->hdr_overflows = 0UL;
98 hdr->hdr_count = 0UL;
100 DPRINT(("[%d] buffer=%p buf_size=%lu hdr_size=%lu hdr_version=%u cur_offs=%lu\n",
101 task->pid,
102 buf,
103 hdr->hdr_buf_size,
104 sizeof(*hdr),
105 hdr->hdr_version,
106 hdr->hdr_cur_offs));
108 return 0;
111 static int
112 default_handler(struct task_struct *task, void *buf, pfm_ovfl_arg_t *arg, struct pt_regs *regs, unsigned long stamp)
114 pfm_default_smpl_hdr_t *hdr;
115 pfm_default_smpl_entry_t *ent;
116 void *cur, *last;
117 unsigned long *e, entry_size;
118 unsigned int npmds, i;
119 unsigned char ovfl_pmd;
120 unsigned char ovfl_notify;
122 if (unlikely(buf == NULL || arg == NULL|| regs == NULL || task == NULL)) {
123 DPRINT(("[%d] invalid arguments buf=%p arg=%p\n", task->pid, buf, arg));
124 return -EINVAL;
127 hdr = (pfm_default_smpl_hdr_t *)buf;
128 cur = buf+hdr->hdr_cur_offs;
129 last = buf+hdr->hdr_buf_size;
130 ovfl_pmd = arg->ovfl_pmd;
131 ovfl_notify = arg->ovfl_notify;
134 * precheck for sanity
136 if ((last - cur) < PFM_DEFAULT_MAX_ENTRY_SIZE) goto full;
138 npmds = hweight64(arg->smpl_pmds[0]);
140 ent = (pfm_default_smpl_entry_t *)cur;
142 prefetch(arg->smpl_pmds_values);
144 entry_size = sizeof(*ent) + (npmds << 3);
146 /* position for first pmd */
147 e = (unsigned long *)(ent+1);
149 hdr->hdr_count++;
151 DPRINT_ovfl(("[%d] count=%lu cur=%p last=%p free_bytes=%lu ovfl_pmd=%d ovfl_notify=%d npmds=%u\n",
152 task->pid,
153 hdr->hdr_count,
154 cur, last,
155 last-cur,
156 ovfl_pmd,
157 ovfl_notify, npmds));
160 * current = task running at the time of the overflow.
162 * per-task mode:
163 * - this is ususally the task being monitored.
164 * Under certain conditions, it might be a different task
166 * system-wide:
167 * - this is not necessarily the task controlling the session
169 ent->pid = current->pid;
170 ent->ovfl_pmd = ovfl_pmd;
171 ent->last_reset_val = arg->pmd_last_reset; //pmd[0].reg_last_reset_val;
174 * where did the fault happen (includes slot number)
176 ent->ip = regs->cr_iip | ((regs->cr_ipsr >> 41) & 0x3);
178 ent->tstamp = stamp;
179 ent->cpu = smp_processor_id();
180 ent->set = arg->active_set;
181 ent->tgid = current->tgid;
184 * selectively store PMDs in increasing index number
186 if (npmds) {
187 unsigned long *val = arg->smpl_pmds_values;
188 for(i=0; i < npmds; i++) {
189 *e++ = *val++;
194 * update position for next entry
196 hdr->hdr_cur_offs += entry_size;
197 cur += entry_size;
200 * post check to avoid losing the last sample
202 if ((last - cur) < PFM_DEFAULT_MAX_ENTRY_SIZE) goto full;
205 * keep same ovfl_pmds, ovfl_notify
207 arg->ovfl_ctrl.bits.notify_user = 0;
208 arg->ovfl_ctrl.bits.block_task = 0;
209 arg->ovfl_ctrl.bits.mask_monitoring = 0;
210 arg->ovfl_ctrl.bits.reset_ovfl_pmds = 1; /* reset before returning from interrupt handler */
212 return 0;
213 full:
214 DPRINT_ovfl(("sampling buffer full free=%lu, count=%lu, ovfl_notify=%d\n", last-cur, hdr->hdr_count, ovfl_notify));
217 * increment number of buffer overflow.
218 * important to detect duplicate set of samples.
220 hdr->hdr_overflows++;
223 * if no notification requested, then we saturate the buffer
225 if (ovfl_notify == 0) {
226 arg->ovfl_ctrl.bits.notify_user = 0;
227 arg->ovfl_ctrl.bits.block_task = 0;
228 arg->ovfl_ctrl.bits.mask_monitoring = 1;
229 arg->ovfl_ctrl.bits.reset_ovfl_pmds = 0;
230 } else {
231 arg->ovfl_ctrl.bits.notify_user = 1;
232 arg->ovfl_ctrl.bits.block_task = 1; /* ignored for non-blocking context */
233 arg->ovfl_ctrl.bits.mask_monitoring = 1;
234 arg->ovfl_ctrl.bits.reset_ovfl_pmds = 0; /* no reset now */
236 return -1; /* we are full, sorry */
239 static int
240 default_restart(struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
242 pfm_default_smpl_hdr_t *hdr;
244 hdr = (pfm_default_smpl_hdr_t *)buf;
246 hdr->hdr_count = 0UL;
247 hdr->hdr_cur_offs = sizeof(*hdr);
249 ctrl->bits.mask_monitoring = 0;
250 ctrl->bits.reset_ovfl_pmds = 1; /* uses long-reset values */
252 return 0;
255 static int
256 default_exit(struct task_struct *task, void *buf, struct pt_regs *regs)
258 DPRINT(("[%d] exit(%p)\n", task->pid, buf));
259 return 0;
262 static pfm_buffer_fmt_t default_fmt={
263 .fmt_name = "default_format",
264 .fmt_uuid = PFM_DEFAULT_SMPL_UUID,
265 .fmt_arg_size = sizeof(pfm_default_smpl_arg_t),
266 .fmt_validate = default_validate,
267 .fmt_getsize = default_get_size,
268 .fmt_init = default_init,
269 .fmt_handler = default_handler,
270 .fmt_restart = default_restart,
271 .fmt_restart_active = default_restart,
272 .fmt_exit = default_exit,
275 static int __init
276 pfm_default_smpl_init_module(void)
278 int ret;
280 ret = pfm_register_buffer_fmt(&default_fmt);
281 if (ret == 0) {
282 printk("perfmon_default_smpl: %s v%u.%u registered\n",
283 default_fmt.fmt_name,
284 PFM_DEFAULT_SMPL_VERSION_MAJ,
285 PFM_DEFAULT_SMPL_VERSION_MIN);
286 } else {
287 printk("perfmon_default_smpl: %s cannot register ret=%d\n",
288 default_fmt.fmt_name,
289 ret);
292 return ret;
295 static void __exit
296 pfm_default_smpl_cleanup_module(void)
298 int ret;
299 ret = pfm_unregister_buffer_fmt(default_fmt.fmt_uuid);
301 printk("perfmon_default_smpl: unregister %s=%d\n", default_fmt.fmt_name, ret);
304 module_init(pfm_default_smpl_init_module);
305 module_exit(pfm_default_smpl_cleanup_module);