/*
* Copyright (C) 2002-2003 Hewlett-Packard Co
* Stephane Eranian <eranian@hpl.hp.com>
*
* This file implements the default sampling buffer format
* for the Linux/ia64 perfmon-2 subsystem.
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/module.h>
#include <linux/config.h>
#include <linux/init.h>
#include <asm/delay.h>
#include <linux/smp.h>
#include <asm/perfmon.h>
#include <asm/perfmon_default_smpl.h>
MODULE_AUTHOR("Stephane Eranian <eranian@hpl.hp.com>");
MODULE_DESCRIPTION("perfmon default sampling format");
MODULE_LICENSE("GPL");
#define DEFAULT_DEBUG 1
#ifdef DEFAULT_DEBUG
#define DPRINT(a) \
do { \
if (unlikely(pfm_sysctl.debug >0)) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
} while (0)
#define DPRINT_ovfl(a) \
do { \
if (unlikely(pfm_sysctl.debug > 0 && pfm_sysctl.debug_ovfl >0)) { printk("%s.%d: CPU%d ", __FUNCTION__, __LINE__, smp_processor_id()); printk a; } \
} while (0)
#else
#define DPRINT(a)
#define DPRINT_ovfl(a)
#endif
static int
default_validate(struct task_struct *task, unsigned int flags, int cpu, void *data)
{
pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t*)data;
int ret = 0;
if (data == NULL) {
DPRINT(("[%d] no argument passed\n", task->pid));
return -EINVAL;
}
DPRINT(("[%d] validate flags=0x%x CPU%d\n", task->pid, flags, cpu));
/*
* must hold at least the buffer header + one minimally sized entry
*/
if (arg->buf_size < PFM_DEFAULT_SMPL_MIN_BUF_SIZE) return -EINVAL;
DPRINT(("buf_size=%lu\n", arg->buf_size));
return ret;
}
static int
default_get_size(struct task_struct *task, unsigned int flags, int cpu, void *data, unsigned long *size)
{
pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t *)data;
/*
* size has been validated in default_validate
*/
*size = arg->buf_size;
return 0;
}
static int
default_init(struct task_struct *task, void *buf, unsigned int flags, int cpu, void *data)
{
pfm_default_smpl_hdr_t *hdr;
pfm_default_smpl_arg_t *arg = (pfm_default_smpl_arg_t *)data;
hdr = (pfm_default_smpl_hdr_t *)buf;
hdr->hdr_version = PFM_DEFAULT_SMPL_VERSION;
hdr->hdr_buf_size = arg->buf_size;
hdr->hdr_cur_offs = sizeof(*hdr);
hdr->hdr_overflows = 0UL;
hdr->hdr_count = 0UL;
DPRINT(("[%d] buffer=%p buf_size=%lu hdr_size=%lu hdr_version=%u cur_offs=%lu\n",
task->pid,
buf,
hdr->hdr_buf_size,
sizeof(*hdr),
hdr->hdr_version,
hdr->hdr_cur_offs));
return 0;
}
static int
default_handler(struct task_struct *task, void *buf, pfm_ovfl_arg_t *arg, struct pt_regs *regs, unsigned long stamp)
{
pfm_default_smpl_hdr_t *hdr;
pfm_default_smpl_entry_t *ent;
void *cur, *last;
unsigned long *e, entry_size;
unsigned int npmds, i;
unsigned char ovfl_pmd;
unsigned char ovfl_notify;
if (unlikely(buf == NULL || arg == NULL|| regs == NULL || task == NULL)) {
DPRINT(("[%d] invalid arguments buf=%p arg=%p\n", task->pid, buf, arg));
return -EINVAL;
}
hdr = (pfm_default_smpl_hdr_t *)buf;
cur = buf+hdr->hdr_cur_offs;
last = buf+hdr->hdr_buf_size;
ovfl_pmd = arg->ovfl_pmd;
ovfl_notify = arg->ovfl_notify;
/*
* precheck for sanity
*/
if ((last - cur) < PFM_DEFAULT_MAX_ENTRY_SIZE) goto full;
npmds = hweight64(arg->smpl_pmds[0]);
ent = (pfm_default_smpl_entry_t *)cur;
prefetch(arg->smpl_pmds_values);
entry_size = sizeof(*ent) + (npmds << 3);
/* position for first pmd */
e = (unsigned long *)(ent+1);
hdr->hdr_count++;
DPRINT_ovfl(("[%d] count=%lu cur=%p last=%p free_bytes=%lu ovfl_pmd=%d ovfl_notify=%d npmds=%u\n",
task->pid,
hdr->hdr_count,
cur, last,
last-cur,
ovfl_pmd,
ovfl_notify, npmds));
/*
* current = task running at the time of the overflow.
*
* per-task mode:
* - this is ususally the task being monitored.
* Under certain conditions, it might be a different task
*
* system-wide:
* - this is not necessarily the task controlling the session
*/
ent->pid = current->pid;
ent->ovfl_pmd = ovfl_pmd;
ent->last_reset_val = arg->pmd_last_reset; //pmd[0].reg_last_reset_val;
/*
* where did the fault happen (includes slot number)
*/
ent->ip = regs->cr_iip | ((regs->cr_ipsr >> 41) & 0x3);
ent->tstamp = stamp;
ent->cpu = smp_processor_id();
ent->set = arg->active_set;
ent->tgid = current->tgid;
/*
* selectively store PMDs in increasing index number
*/
if (npmds) {
unsigned long *val = arg->smpl_pmds_values;
for(i=0; i < npmds; i++) {
*e++ = *val++;
}
}
/*
* update position for next entry
*/
hdr->hdr_cur_offs += entry_size;
cur += entry_size;
/*
* post check to avoid losing the last sample
*/
if ((last - cur) < PFM_DEFAULT_MAX_ENTRY_SIZE) goto full;
/*
* keep same ovfl_pmds, ovfl_notify
*/
arg->ovfl_ctrl.bits.notify_user = 0;
arg->ovfl_ctrl.bits.block_task = 0;
arg->ovfl_ctrl.bits.mask_monitoring = 0;
arg->ovfl_ctrl.bits.reset_ovfl_pmds = 1; /* reset before returning from interrupt handler */
return 0;
full:
DPRINT_ovfl(("sampling buffer full free=%lu, count=%lu, ovfl_notify=%d\n", last-cur, hdr->hdr_count, ovfl_notify));
/*
* increment number of buffer overflow.
* important to detect duplicate set of samples.
*/
hdr->hdr_overflows++;
/*
* if no notification requested, then we saturate the buffer
*/
if (ovfl_notify == 0) {
arg->ovfl_ctrl.bits.notify_user = 0;
arg->ovfl_ctrl.bits.block_task = 0;
arg->ovfl_ctrl.bits.mask_monitoring = 1;
arg->ovfl_ctrl.bits.reset_ovfl_pmds = 0;
} else {
arg->ovfl_ctrl.bits.notify_user = 1;
arg->ovfl_ctrl.bits.block_task = 1; /* ignored for non-blocking context */
arg->ovfl_ctrl.bits.mask_monitoring = 1;
arg->ovfl_ctrl.bits.reset_ovfl_pmds = 0; /* no reset now */
}
return -1; /* we are full, sorry */
}
static int
default_restart(struct task_struct *task, pfm_ovfl_ctrl_t *ctrl, void *buf, struct pt_regs *regs)
{
pfm_default_smpl_hdr_t *hdr;
hdr = (pfm_default_smpl_hdr_t *)buf;
hdr->hdr_count = 0UL;
hdr->hdr_cur_offs = sizeof(*hdr);
ctrl->bits.mask_monitoring = 0;
ctrl->bits.reset_ovfl_pmds = 1; /* uses long-reset values */
return 0;
}
static int
default_exit(struct task_struct *task, void *buf, struct pt_regs *regs)
{
DPRINT(("[%d] exit(%p)\n", task->pid, buf));
return 0;
}
static pfm_buffer_fmt_t default_fmt={
.fmt_name = "default_format",
.fmt_uuid = PFM_DEFAULT_SMPL_UUID,
.fmt_arg_size = sizeof(pfm_default_smpl_arg_t),
.fmt_validate = default_validate,
.fmt_getsize = default_get_size,
.fmt_init = default_init,
.fmt_handler = default_handler,
.fmt_restart = default_restart,
.fmt_restart_active = default_restart,
.fmt_exit = default_exit,
};
static int __init
pfm_default_smpl_init_module(void)
{
int ret;
ret = pfm_register_buffer_fmt(&default_fmt);
if (ret == 0) {
printk("perfmon_default_smpl: %s v%u.%u registered\n",
default_fmt.fmt_name,
PFM_DEFAULT_SMPL_VERSION_MAJ,
PFM_DEFAULT_SMPL_VERSION_MIN);
} else {
printk("perfmon_default_smpl: %s cannot register ret=%d\n",
default_fmt.fmt_name,
ret);
}
return ret;
}
static void __exit
pfm_default_smpl_cleanup_module(void)
{
int ret;
ret = pfm_unregister_buffer_fmt(default_fmt.fmt_uuid);
printk("perfmon_default_smpl: unregister %s=%d\n", default_fmt.fmt_name, ret);
}
module_init(pfm_default_smpl_init_module);
module_exit(pfm_default_smpl_cleanup_module);
