blob: 2f9b38cbf1ccdece6bf14b407ab1a5d420a931ad [file] [log] [blame]
/**
* @file opd_proc.c
* Management of processes
*
* @remark Copyright 2002 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon
* @author Philippe Elie
*/
#include "op_hw_config.h"
#include "opd_proc.h"
#include "opd_image.h"
#include "opd_mapping.h"
#include "opd_sample_files.h"
#include "opd_kernel.h"
#include "opd_24_stats.h"
#include "opd_printf.h"
#include "oprofiled.h"
#include "op_interface.h"
#include "op_libiberty.h"
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* size of process hash table */
#define OPD_MAX_PROC_HASH 1024
extern int cpu_number;
/* hash of process lists */
static struct list_head opd_procs[OPD_MAX_PROC_HASH];
/* statistics purpose */
static int nr_procs;
void opd_init_procs(void)
{
int i;
for (i = 0; i < OPD_MAX_PROC_HASH; i++)
list_init(&opd_procs[i]);
}
int opd_get_nr_procs(void)
{
return nr_procs;
}
/**
* proc_hash - hash pid value
* @param tid pid value to hash
*
*/
inline static uint proc_hash(pid_t tid)
{
/* FIXME: hash tgid too! */
return ((tid >> 4) ^ (tid)) % OPD_MAX_PROC_HASH;
}
struct opd_proc * opd_new_proc(pid_t tid, pid_t tgid)
{
struct opd_proc * proc;
nr_procs++;
proc = xmalloc(sizeof(struct opd_proc));
list_init(&proc->maps);
proc->name = NULL;
proc->tid = tid;
proc->tgid = tgid;
proc->dead = 0;
proc->accessed = 0;
list_add(&proc->next, &opd_procs[proc_hash(tid)]);
return proc;
}
struct opd_proc * opd_get_proc(pid_t tid, pid_t tgid)
{
struct opd_proc * proc;
uint hash = proc_hash(tid);
struct list_head * pos, *pos2;
opd_24_stats[OPD_PROC_QUEUE_ACCESS]++;
list_for_each_safe(pos, pos2, &opd_procs[hash]) {
opd_24_stats[OPD_PROC_QUEUE_DEPTH]++;
proc = list_entry(pos, struct opd_proc, next);
if (tid == proc->tid && tgid == proc->tgid) {
/* LRU to head */
list_del(&proc->next);
list_add(&proc->next, &opd_procs[hash]);
return proc;
}
}
return NULL;
}
/**
* verb_show_sample - print the sample out to the log
* @param offset the offset value
* @param map map to print
*/
inline static void
verb_show_sample(unsigned long offset, struct opd_map * map)
{
verbprintf(vsamples, "DO_PUT_SAMPLE : calc offset 0x%.8lx, "
"map start 0x%.8lx, end 0x%.8lx, offset 0x%.8lx, name \"%s\"\n",
offset, map->start, map->end, map->offset,
map->image->name);
}
void opd_put_image_sample(struct opd_image * image, unsigned long offset,
u32 counter)
{
struct opd_24_sfile * sfile;
int err;
if (image->ignored)
return;
if (!image->sfiles[cpu_number]) {
image->sfiles[cpu_number] =
xcalloc(OP_MAX_COUNTERS, sizeof(struct op_24_sfile *));
}
sfile = image->sfiles[cpu_number][counter];
if (!sfile || !odb_open_count(&sfile->sample_file)) {
if (opd_open_24_sample_file(image, counter, cpu_number)) {
/* opd_open_24_sample_file output an error message */
opd_24_stats[OPD_LOST_SAMPLEFILE]++;
return;
}
sfile = image->sfiles[cpu_number][counter];
}
err = odb_update_node(&sfile->sample_file, offset);
if (err) {
fprintf(stderr, "%s\n", strerror(err));
abort();
}
opd_24_sfile_lru(sfile);
}
/**
* opd_lookup_maps - lookup a proc mappings for a sample
* @param proc proc to lookup
* @param sample sample to lookup
*
* iterate through the proc maps searching the mapping which owns sample
* if sucessful sample count will be updated and we return non-zero
*/
static int opd_lookup_maps(struct opd_proc * proc,
struct op_sample const * sample)
{
struct list_head * pos;
proc->accessed = 1;
opd_24_stats[OPD_MAP_ARRAY_ACCESS]++;
list_for_each(pos, &proc->maps) {
struct opd_map * map = list_entry(pos, struct opd_map, next);
if (opd_is_in_map(map, sample->eip)) {
unsigned long offset = opd_map_offset(map, sample->eip);
if (map->image != NULL) {
verb_show_sample(offset, map);
opd_put_image_sample(map->image, offset, sample->counter);
}
opd_24_stats[OPD_PROCESS]++;
return 1;
}
opd_24_stats[OPD_MAP_ARRAY_DEPTH]++;
}
return 0;
}
void opd_put_sample(struct op_sample const * sample)
{
struct opd_proc * proc;
int in_kernel_eip = opd_eip_is_kernel(sample->eip);
opd_24_stats[OPD_SAMPLES]++;
verbprintf(vsamples, "DO_PUT_SAMPLE: c%d, EIP 0x%.8lx, tgid %.6d pid %.6d\n",
sample->counter, sample->eip, sample->tgid, sample->pid);
if (!separate_kernel && in_kernel_eip) {
opd_handle_kernel_sample(sample->eip, sample->counter);
return;
}
if (!(proc = opd_get_proc(sample->pid, sample->tgid))) {
if (in_kernel_eip || no_vmlinux) {
/* idle task get a 0 pid and is hidden we can never get
* a proc so on we fall back to put sample in vmlinux
* or module samples files. Here we will catch also
* sample for newly created kernel thread, currently
* we can handle properly only kenel thread created
* at daemon startup time */
opd_handle_kernel_sample(sample->eip, sample->counter);
} else {
verbprintf(vmisc, "No proc info for tgid %.6d pid %.6d.\n",
sample->tgid, sample->pid);
opd_24_stats[OPD_LOST_PROCESS]++;
}
return;
}
if (opd_lookup_maps(proc, sample))
return;
if (in_kernel_eip) {
opd_add_kernel_map(proc, sample->eip);
if (opd_lookup_maps(proc, sample))
return;
}
/* couldn't locate it */
verbprintf(vsamples, "Couldn't find map for pid %.6d, EIP 0x%.8lx.\n",
sample->pid, sample->eip);
opd_24_stats[OPD_LOST_MAP_PROCESS]++;
}
void opd_handle_fork(struct op_note const * note)
{
struct opd_proc * old;
struct opd_proc * proc;
struct list_head * pos;
verbprintf(vmisc, "DO_FORK: from %d, %d to %ld, %ld\n", note->pid, note->tgid,
note->addr, note->len);
old = opd_get_proc(note->pid, note->tgid);
/* we can quite easily get a fork() after the execve() because the
* notifications are racy. In particular, the fork notification is
* done on parent return (so we know the pid), but this will often be
* after the execve is done by the child.
*
* So we only create a new setup if it doesn't exist already, allowing
* both the clone() and the execve() cases to work.
*/
if (opd_get_proc(note->addr, note->len))
return;
/* eip/len is actually tid/tgid of new process */
proc = opd_new_proc(note->addr, note->len);
if (!old)
return;
/* copy the maps */
list_for_each(pos, &old->maps) {
struct opd_map * map = list_entry(pos, struct opd_map, next);
if (!separate_thread) {
opd_add_mapping(proc, map->image, map->start,
map->offset, map->end);
} else {
/* when separating thread we can't create blindly a new
* image e.g. pid re-use, multiple mapping with the
* same mapping name etc. */
struct opd_image * image =
opd_get_image(map->image->name, old->name,
map->image->kernel, note->addr, note->len);
opd_add_mapping(proc, image, map->start, map->offset,
map->end);
}
}
}
void opd_handle_exec(pid_t tid, pid_t tgid)
{
struct opd_proc * proc;
verbprintf(vmisc, "DO_EXEC: pid %u %u\n", tid, tgid);
/* There is a race for samples received between fork/exec sequence.
* These samples belong to the old mapping but we can not say if
* samples has been received before the exec or after. This explains
* the message "Couldn't find map for ..." in verbose mode.
*
* Unhappily, it is difficult to get an estimation of these misplaced
* samples, the error message can count only out of mapping samples but
* not samples between the race and inside the mapping of the exec'ed
* process :/.
*
* Trying to save old mapping is not correct due the above reason. The
* only manner to handle this is to flush the module samples hash table
* after each fork which is unacceptable for performance reasons */
proc = opd_get_proc(tid, tgid);
if (proc) {
opd_kill_maps(proc);
/* proc->name will be set when the next mapping occurs */
free((char *)proc->name);
proc->name = NULL;
} else {
opd_new_proc(tid, tgid);
}
}
void opd_handle_exit(struct op_note const * note)
{
struct opd_proc * proc;
verbprintf(vmisc, "DO_EXIT: process %d\n", note->pid);
proc = opd_get_proc(note->pid, note->tgid);
if (proc) {
proc->dead = 1;
proc->accessed = 1;
} else {
verbprintf(vmisc, "unknown proc %u just exited.\n", note->pid);
}
}
typedef void (*opd_proc_cb)(struct opd_proc *);
/**
* @param proc_cb callback to apply onto each existing proc struct
*
* the callback receive a struct opd_proc * (not a const struct) and is
* allowed to freeze the proc struct itself.
*/
static void opd_for_each_proc(opd_proc_cb proc_cb)
{
struct list_head * pos;
struct list_head * pos2;
int i;
for (i = 0; i < OPD_MAX_PROC_HASH; ++i) {
list_for_each_safe(pos, pos2, &opd_procs[i]) {
struct opd_proc * proc =
list_entry(pos, struct opd_proc, next);
proc_cb(proc);
}
}
}
/**
* opd_delete_proc - delete a process
* @param proc process to delete
*
* Remove the process proc from the process list and free
* the associated structures.
*/
static void opd_delete_proc(struct opd_proc * proc)
{
--nr_procs;
list_del(&proc->next);
opd_kill_maps(proc);
if (proc->name)
free((char *)proc->name);
free(proc);
}
void opd_proc_cleanup(void)
{
opd_for_each_proc(opd_delete_proc);
}
/**
* opd_age_proc - age a struct opd_proc
* @param proc proc to age
*
* age dead proc in such way if a proc doesn't receive any samples
* between two age_proc the opd_proc struct is deleted
*/
static void opd_age_proc(struct opd_proc * proc)
{
// delay death whilst its still being accessed
if (proc->dead) {
proc->dead += proc->accessed;
proc->accessed = 0;
if (--proc->dead == 0)
opd_delete_proc(proc);
}
}
void opd_age_procs(void)
{
opd_for_each_proc(opd_age_proc);
}
/**
* opd_remove_kernel_mapping - remove all kernel mapping for an opd_proc
* @param proc proc where mappings must be updated.
*
* invalidate (by removing them) all kernel mapping. This function do nothing
* when separate_kernel == 0 because we don't add mapping for kernel
* sample in proc struct.
*/
static void opd_remove_kernel_mapping(struct opd_proc * proc)
{
struct list_head * pos, * pos2;
list_for_each_safe(pos, pos2, &proc->maps) {
struct opd_map * map = list_entry(pos, struct opd_map, next);
if (opd_eip_is_kernel(map->start + map->offset)) {
list_del(pos);
opd_delete_image(map->image);
free(map);
}
}
}
void opd_clear_kernel_mapping(void)
{
opd_for_each_proc(opd_remove_kernel_mapping);
}