Hepimiz merak edebiliriz şu işletim sistemleri nasıl kodlanıyor vs vs.Birde bunun kodlarını merak ederiz :)
Bende biraz araştırdım açık kaynak olarak verilen kernel kodlarını buldum pek zor olmadı gerçi :)
SAdece çok çok küçük bir yerini veriyorum :)
/*
* builtin-annotate.c
*
* Builtin annotate command: Analyze the perf.data input file,
* look up and read DSOs and symbol information and display
* a histogram of results, along various sorting keys.
*/
#include "builtin.h"
#include "util/util.h"
#include "util/color.h"
#include
<linux/list.h>
#include "util/cache.h"
#include
<linux/rbtree.h>
#include "util/symbol.h"
#include "util/string.h"
#include "perf.h"
#include "util/debug.h"
#include "util/event.h"
#include "util/parse-options.h"
#include "util/parse-events.h"
#include "util/thread.h"
#include "util/sort.h"
#include "util/hist.h"
#include "util/session.h"
static char const *input_name = "perf.data";
static int force;
static int full_paths;
static int print_line;
struct sym_hist {
u64 sum;
u64 ip[0];
};
struct sym_ext {
struct rb_node node;
double percent;
char *path;
};
struct sym_priv {
struct sym_hist *hist;
struct sym_ext *ext;
};
static const char *sym_hist_filter;
static int symbol_filter(struct map *map __used, struct symbol *sym)
{
if (sym_hist_filter == NULL ||
strcmp(sym->name, sym_hist_filter) == 0) {
struct sym_priv *priv = symbol__priv(sym);
const int size = (sizeof(*priv->hist) +
(sym->end - sym->start) * sizeof(u64));
priv->hist = malloc(size);
if (priv->hist)
memset(priv->hist, 0, size);
return 0;
}
/*
* FIXME: We should really filter it out, as we don't want to go thru symbols
* we're not interested, and if a DSO ends up with no symbols, delete it too,
* but right now the kernel loading routines in symbol.c bail out if no symbols
* are found, fix it later.
*/
return 0;
}
/*
* collect histogram counts
*/
static void hist_hit(struct hist_entry *he, u64 ip)
{
unsigned int sym_size, offset;
struct symbol *sym = he->sym;
struct sym_priv *priv;
struct sym_hist *h;
he->count++;
if (!sym || !he->map)
return;
priv = symbol__priv(sym);
if (!priv->hist)
return;
sym_size = sym->end - sym->start;
offset = ip - sym->start;
if (verbose)
fprintf(stderr, "%s: ip=%Lx\n", __func__,
he->map->unmap_ip(he->map, ip));
if (offset >= sym_size)
return;
h = priv->hist;
h->sum++;
h->ip[offset]++;
if (verbose >= 3)
printf("%p %s: count++ [ip: %p, %08Lx] => %Ld\n",
(void *)(unsigned long)he->sym->start,
he->sym->name,
(void *)(unsigned long)ip, ip - he->sym->start,
h->ip[offset]);
}
static int perf_session__add_hist_entry(struct perf_session *self,
struct addr_location *al, u64 count)
{
bool hit;
struct hist_entry *he = __perf_session__add_hist_entry(self, al, NULL,
count, &hit);
if (he == NULL)
return -ENOMEM;
hist_hit(he, al->addr);
return 0;
}
static int process_sample_event(event_t *event, struct perf_session *session)
{
struct addr_location al;
dump_printf("(IP, %d): %d: %p\n", event->header.misc,
event->ip.pid, (void *)(long)event->ip.ip);
if (event__preprocess_sample(event, session, &al, symbol_filter) < 0) {
fprintf(stderr, "problem processing %d event, skipping it.\n",
event->header.type);
return -1;
}
if (!al.filtered && perf_session__add_hist_entry(session, &al, 1)) {
fprintf(stderr, "problem incrementing symbol count, "
"skipping event\n");
return -1;
}
return 0;
}
static int parse_line(FILE *file, struct hist_entry *he, u64 len)
{
struct symbol *sym = he->sym;
char *line = NULL, *tmp, *tmp2;
static const char *prev_line;
static const char *prev_color;
unsigned int offset;
size_t line_len;
u64 start;
s64 line_ip;
int ret;
char *c;
if (getline(&line, &line_len, file) < 0)
return -1;
if (!line)
return -1;
c = strchr(line, '\n');
if (c)
*c = 0;
line_ip = -1;
offset = 0;
ret = -2;
/*
* Strip leading spaces:
*/
tmp = line;
while (*tmp) {
if (*tmp != ' ')
break;
tmp++;
}
if (*tmp) {
/*
* Parse hexa addresses followed by ':'
*/
line_ip = strtoull(tmp, &tmp2, 16);
if (*tmp2 != ':')
line_ip = -1;
}
start = he->map->unmap_ip(he->map, sym->start);
if (line_ip != -1) {
const char *path = NULL;
unsigned int hits = 0;
double percent = 0.0;
const char *color;
struct sym_priv *priv = symbol__priv(sym);
struct sym_ext *sym_ext = priv->ext;
struct sym_hist *h = priv->hist;
offset = line_ip - start;
if (offset < len)
hits = h->ip[offset];
if (offset < len && sym_ext) {
path = sym_ext[offset].path;
percent = sym_ext[offset].percent;
} else if (h->sum)
percent = 100.0 * hits / h->sum;
color = get_percent_color(percent);
/*
* Also color the filename and line if needed, with
* the same color than the percentage. Don't print it
* twice for close colored ip with the same filename:line
*/
if (path) {
if (!prev_line || strcmp(prev_line, path)
|| color != prev_color) {
color_fprintf(stdout, color, " %s", path);
prev_line = path;
prev_color = color;
}
}
color_fprintf(stdout, color, " %7.2f", percent);
printf(" : ");
color_fprintf(stdout, PERF_COLOR_BLUE, "%s\n", line);
} else {
if (!*line)
printf(" :\n");
else
printf(" : %s\n", line);
}
return 0;
}
static struct rb_root root_sym_ext;
static void insert_source_line(struct sym_ext *sym_ext)
{
struct sym_ext *iter;
struct rb_node **p = &root_sym_ext.rb_node;
struct rb_node *parent = NULL;
while (*p != NULL) {
parent = *p;
iter = rb_entry(parent, struct sym_ext, node);
if (sym_ext->percent > iter->percent)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
rb_link_node(&sym_ext->node, parent, p);
rb_insert_color(&sym_ext->node, &root_sym_ext);
}
static void free_source_line(struct hist_entry *he, int len)
{
struct sym_priv *priv = symbol__priv(he->sym);
struct sym_ext *sym_ext = priv->ext;
int i;
if (!sym_ext)
return;
for (i = 0; i < len; i++)
free(sym_ext.path);
free(sym_ext);
priv->ext = NULL;
root_sym_ext = RB_ROOT;
}
/* Get the filename:line for the colored entries */
static void
get_source_line(struct hist_entry *he, int len, const char *filename)
{
struct symbol *sym = he->sym;
u64 start;
int i;
char cmd[PATH_MAX * 2];
struct sym_ext *sym_ext;
struct sym_priv *priv = symbol__priv(sym);
struct sym_hist *h = priv->hist;
if (!h->sum)
return;
sym_ext = priv->ext = calloc(len, sizeof(struct sym_ext));
if (!priv->ext)
return;
start = he->map->unmap_ip(he->map, sym->start);
for (i = 0; i < len; i++) {
char *path = NULL;
size_t line_len;
u64 offset;
FILE *fp;
sym_ext.percent = 100.0 * h->ip / h->sum;
if (sym_ext.percent <= 0.5)
continue;
offset = start + i;
sprintf(cmd, "addr2line -e %s %016llx", filename, offset);
fp = popen(cmd, "r");
if (!fp)
continue;
if (getline(&path, &line_len, fp) < 0 || !line_len)
goto next;
sym_ext.path = malloc(sizeof(char) * line_len + 1);
if (!sym_ext.path)
goto next;
strcpy(sym_ext.path, path);
insert_source_line(&sym_ext);
next:
pclose(fp);
}
}
static void print_summary(const char *filename)
{
struct sym_ext *sym_ext;
struct rb_node *node;
printf("\nSorted summary for file %s\n", filename);
printf("----------------------------------------------\n\n");
if (RB_EMPTY_ROOT(&root_sym_ext)) {
printf(" Nothing higher than %1.1f%%\n", MIN_GREEN);
return;
}
node = rb_first(&root_sym_ext);
while (node) {
double percent;
const char *color;
char *path;
sym_ext = rb_entry(node, struct sym_ext, node);
percent = sym_ext->percent;
color = get_percent_color(percent);
path = sym_ext->path;
color_fprintf(stdout, color, " %7.2f %s", percent, path);
node = rb_next(node);
}
}
static void annotate_sym(struct hist_entry *he)
{
struct map *map = he->map;
struct dso *dso = map->dso;
struct symbol *sym = he->sym;
const char *filename = dso->long_name, *d_filename;
u64 len;
char command[PATH_MAX*2];
FILE *file;
if (!filename)
return;
if (verbose)
fprintf(stderr, "%s: filename=%s, sym=%s, start=%Lx, end=%Lx\n",
__func__, filename, sym->name,
map->unmap_ip(map, sym->start),
map->unmap_ip(map, sym->end));
if (full_paths)
d_filename = filename;
else
d_filename = basename(filename);
len = sym->end - sym->start;
if (print_line) {
get_source_line(he, len, filename);
print_summary(filename);
}
printf("\n\n------------------------------------------------\n");
printf(" Percent | Source code & Disassembly of %s\n", d_filename);
printf("------------------------------------------------\n");
if (verbose >= 2)
printf("annotating [%p] %30s : [%p] %30s\n",
dso, dso->long_name, sym, sym->name);
sprintf(command, "objdump --start-address=0x%016Lx --stop-address=0x%016Lx -dS %s|grep -v %s",
map->unmap_ip(map, sym->start), map->unmap_ip(map, sym->end),
filename, filename);
if (verbose >= 3)
printf("doing: %s\n", command);
file = popen(command, "r");
if (!file)
return;
while (!feof(file)) {
if (parse_line(file, he, len) < 0)
break;
}
pclose(file);
if (print_line)
free_source_line(he, len);
}
static void perf_session__find_annotations(struct perf_session *self)
{
struct rb_node *nd;
for (nd = rb_first(&self->hists); nd; nd = rb_next(nd)) {
struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node);
struct sym_priv *priv;
if (he->sym == NULL)
continue;
priv = symbol__priv(he->sym);
if (priv->hist == NULL)
continue;
annotate_sym(he);
/*
* Since we have a hist_entry per IP for the same symbol, free
* he->sym->hist to signal we already processed this symbol.
*/
free(priv->hist);
priv->hist = NULL;
}
}
static struct perf_event_ops event_ops = {
.process_sample_event = process_sample_event,
.process_mmap_event = event__process_mmap,
.process_comm_event = event__process_comm,
.process_fork_event = event__process_task,
};
static int __cmd_annotate(void)
{
int ret;
struct perf_session *session;
session = perf_session__new(input_name, O_RDONLY, force);
if (session == NULL)
return -ENOMEM;
ret = perf_session__process_events(session, &event_ops);
if (ret)
goto out_delete;
if (dump_trace) {
event__print_totals();
goto out_delete;
}
if (verbose > 3)
perf_session__fprintf(session, stdout);
if (verbose > 2)
dsos__fprintf(stdout);
perf_session__collapse_resort(session);
perf_session__output_resort(session, session->event_total[0]);
perf_session__find_annotations(session);
out_delete:
perf_session__delete(session);
return ret;
}
static const char * const annotate_usage[] = {
"perf annotate [<options>] <command>",
NULL
};
static const struct option options[] = {
OPT_STRING('i', "input", &input_name, "file",
"input file name"),
OPT_STRING('s', "symbol", &sym_hist_filter, "symbol",
"symbol to annotate"),
OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
OPT_BOOLEAN('v', "verbose", &verbose,
"be more verbose (show symbol address, etc)"),
OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
"dump raw trace in ASCII"),
OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
"file", "vmlinux pathname"),
OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
"load module symbols - WARNING: use only with -k and LIVE kernel"),
OPT_BOOLEAN('l', "print-line", &print_line,
"print matching source lines (may be slow)"),
OPT_BOOLEAN('P', "full-paths", &full_paths,
"Don't shorten the displayed pathnames"),
OPT_END()
};
int cmd_annotate(int argc, const char **argv, const char *prefix __used)
{
argc = parse_options(argc, argv, options, annotate_usage, 0);
symbol_conf.priv_size = sizeof(struct sym_priv);
symbol_conf.try_vmlinux_path = true;
if (symbol__init() < 0)
return -1;
setup_sorting(annotate_usage, options);
if (argc) {
/*
* Special case: if there's an argument left then assume tha
* it's a symbol filter:
*/
if (argc > 1)
usage_with_options(annotate_usage, options);
sym_hist_filter = argv[0];
}
setup_pager();
if (field_sep && *field_sep == '.') {
fputs("'.' is the only non valid --field-separator argument\n",
stderr);
exit(129);
}
return __cmd_annotate();
}
Biliyorum aşşagı inmekten bıktınız ama :)))
