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.
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 #define DEFAULT_DEBUG 1
28 if (unlikely(pfm_sysctl.debug >0)) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
31 #define DPRINT_ovfl(a) \
33 if (unlikely(pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0)) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
38 #define DPRINT_ovfl(a)
42 default_validate(struct task_struct *task, unsigned int flags, int cpu, void *data)
44 pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t*)data;
48 DPRINT(("[%d] no argument passed\n", task->pid));
52 DPRINT(("[%d] validate flags=0x%x CPU%d\n", task->pid, flags, cpu));
55 * must hold at least the buffer header + one minimally sized entry
57 if (arg->buf_size < PFM_DEFAULT_SMPL_MIN_BUF_SIZE) return -EINVAL;
59 DPRINT(("buf_size=%lu\n", arg->buf_size));
65 default_get_size(struct task_struct *task, unsigned int flags, int cpu, void *data, unsigned long *size)
67 pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t *)data;
70 * size has been validated in default_validate
72 *size = arg->buf_size;
78 default_init(struct task_struct *task, void *buf, unsigned int flags, int cpu, void *data)
80 pfm_default_smpl_hdr_t *hdr;
81 pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t *)data;
83 hdr = (pfm_default_smpl_hdr_t *)buf;
85 hdr->hdr_version = PFM_DEFAULT_SMPL_VERSION;
86 hdr->hdr_buf_size = arg->buf_size;
87 hdr->hdr_cur_offs = sizeof(*hdr);
88 hdr->hdr_overflows = 0UL;
91 DPRINT(("[%d] buffer=%p buf_size=%lu hdr_size=%lu hdr_version=%u cur_offs=%lu\n",
103 default_handler(struct task_struct *task, void *buf, pfm_ovfl_arg_t *arg, struct pt_regs *regs, unsigned long stamp)
105 pfm_default_smpl_hdr_t *hdr;
106 pfm_default_smpl_entry_t *ent;
108 unsigned long *e, entry_size;
109 unsigned int npmds, i;
110 unsigned char ovfl_pmd;
111 unsigned char ovfl_notify;
113 if (unlikely(buf == NULL || arg == NULL|| regs == NULL || task == NULL)) {
114 DPRINT(("[%d] invalid arguments buf=%p arg=%p\n", task->pid, buf, arg));
118 hdr = (pfm_default_smpl_hdr_t *)buf;
119 cur = buf+hdr->hdr_cur_offs;
120 last = buf+hdr->hdr_buf_size;
121 ovfl_pmd = arg->ovfl_pmd;
122 ovfl_notify = arg->ovfl_notify;
125 * precheck for sanity
127 if ((last - cur) < PFM_DEFAULT_MAX_ENTRY_SIZE) goto full;
129 npmds = hweight64(arg->smpl_pmds[0]);
131 ent = (pfm_default_smpl_entry_t *)cur;
133 prefetch(arg->smpl_pmds_values);
135 entry_size = sizeof(*ent) + (npmds << 3);
137 /* position for first pmd */
138 e = (unsigned long *)(ent+1);
142 DPRINT_ovfl(("[%d] count=%lu cur=%p last=%p free_bytes=%lu ovfl_pmd=%d ovfl_notify=%d npmds=%u\n",
148 ovfl_notify, npmds));
151 * current = task running at the time of the overflow.
154 * - this is ususally the task being monitored.
155 * Under certain conditions, it might be a different task
158 * - this is not necessarily the task controlling the session
160 ent->pid = current->pid;
161 ent->ovfl_pmd = ovfl_pmd;
162 ent->last_reset_val = arg->pmd_last_reset; //pmd[0].reg_last_reset_val;
165 * where did the fault happen (includes slot number)
167 ent->ip = regs->cr_iip | ((regs->cr_ipsr >> 41) & 0x3);
170 ent->cpu = smp_processor_id();
171 ent->set = arg->active_set;
172 ent->tgid = current->tgid;
175 * selectively store PMDs in increasing index number
178 unsigned long *val = arg->smpl_pmds_values;
179 for(i=0; i < npmds; i++) {
185 * update position for next entry
187 hdr->hdr_cur_offs += entry_size;
191 * post check to avoid losing the last sample
193 if ((last - cur) < PFM_DEFAULT_MAX_ENTRY_SIZE) goto full;
196 * keep same ovfl_pmds, ovfl_notify
198 arg->ovfl_ctrl.bits.notify_user = 0;
199 arg->ovfl_ctrl.bits.block_task = 0;
200 arg->ovfl_ctrl.bits.mask_monitoring = 0;
201 arg->ovfl_ctrl.bits.reset_ovfl_pmds = 1; /* reset before returning from interrupt handler */
205 DPRINT_ovfl(("sampling buffer full free=%lu, count=%lu, ovfl_notify=%d\n", last-cur, hdr->hdr_count, ovfl_notify));
208 * increment number of buffer overflow.
209 * important to detect duplicate set of samples.
211 hdr->hdr_overflows++;
214 * if no notification requested, then we saturate the buffer
216 if (ovfl_notify == 0) {
217 arg->ovfl_ctrl.bits.notify_user = 0;
218 arg->ovfl_ctrl.bits.block_task = 0;
219 arg->ovfl_ctrl.bits.mask_monitoring = 1;
220 arg->ovfl_ctrl.bits.reset_ovfl_pmds = 0;
222 arg->ovfl_ctrl.bits.notify_user = 1;
223 arg->ovfl_ctrl.bits.block_task = 1; /* ignored for non-blocking context */
224 arg->ovfl_ctrl.bits.mask_monitoring = 1;
225 arg->ovfl_ctrl.bits.reset_ovfl_pmds = 0; /* no reset now */
227 return -1; /* we are full, sorry */
231 default_restart(struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
233 pfm_default_smpl_hdr_t *hdr;
235 hdr = (pfm_default_smpl_hdr_t *)buf;
237 hdr->hdr_count = 0UL;
238 hdr->hdr_cur_offs = sizeof(*hdr);
240 ctrl->bits.mask_monitoring = 0;
241 ctrl->bits.reset_ovfl_pmds = 1; /* uses long-reset values */
247 default_exit(struct task_struct *task, void *buf, struct pt_regs *regs)
249 DPRINT(("[%d] exit(%p)\n", task->pid, buf));
253 static pfm_buffer_fmt_t default_fmt={
254 .fmt_name = "default_format",
255 .fmt_uuid = PFM_DEFAULT_SMPL_UUID,
256 .fmt_arg_size = sizeof(pfm_default_smpl_arg_t),
257 .fmt_validate = default_validate,
258 .fmt_getsize = default_get_size,
259 .fmt_init = default_init,
260 .fmt_handler = default_handler,
261 .fmt_restart = default_restart,
262 .fmt_restart_active = default_restart,
263 .fmt_exit = default_exit,
267 pfm_default_smpl_init_module(void)
271 ret = pfm_register_buffer_fmt(&default_fmt);
273 printk("perfmon_default_smpl: %s v%u.%u registered\n",
274 default_fmt.fmt_name,
275 PFM_DEFAULT_SMPL_VERSION_MAJ,
276 PFM_DEFAULT_SMPL_VERSION_MIN);
278 printk("perfmon_default_smpl: %s cannot register ret=%d\n",
279 default_fmt.fmt_name,
287 pfm_default_smpl_cleanup_module(void)
290 ret = pfm_unregister_buffer_fmt(default_fmt.fmt_uuid);
292 printk("perfmon_default_smpl: unregister %s=%d\n", default_fmt.fmt_name, ret);
295 module_init(pfm_default_smpl_init_module);
296 module_exit(pfm_default_smpl_cleanup_module);