perf probe: List probes with line number and file name

Improve --list to show current exist probes with line number and
file name. This enables user easily to check which line is
already probed.

for example:

 ./perf probe --list
 probe:vfs_read       (on vfs_read:8@linux-2.6-tip/fs/read_write.c)

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20100316220619.32050.48702.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Masami Hiramatsu 2010-03-16 18:06:19 -04:00 committed by Ingo Molnar
parent 4235b0454e
commit fb1587d869
3 changed files with 116 additions and 13 deletions

View File

@ -70,7 +70,6 @@ static int e_snprintf(char *str, size_t size, const char *format, ...)
return ret; return ret;
} }
static struct map_groups kmap_groups; static struct map_groups kmap_groups;
static struct map *kmaps[MAP__NR_TYPES]; static struct map *kmaps[MAP__NR_TYPES];
@ -357,27 +356,39 @@ void parse_kprobe_trace_command(const char *cmd, struct kprobe_trace_event *tev)
/* Compose only probe point (not argument) */ /* Compose only probe point (not argument) */
static char *synthesize_perf_probe_point(struct perf_probe_point *pp) static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
{ {
char *buf; char *buf, *tmp;
char offs[64] = "", line[64] = ""; char offs[32] = "", line[32] = "", file[32] = "";
int ret; int ret, len;
buf = xzalloc(MAX_CMDLEN); buf = xzalloc(MAX_CMDLEN);
if (pp->offset) { if (pp->offset) {
ret = e_snprintf(offs, 64, "+%lu", pp->offset); ret = e_snprintf(offs, 32, "+%lu", pp->offset);
if (ret <= 0) if (ret <= 0)
goto error; goto error;
} }
if (pp->line) { if (pp->line) {
ret = e_snprintf(line, 64, ":%d", pp->line); ret = e_snprintf(line, 32, ":%d", pp->line);
if (ret <= 0)
goto error;
}
if (pp->file) {
len = strlen(pp->file) - 32;
if (len < 0)
len = 0;
tmp = strchr(pp->file + len, '/');
if (!tmp)
tmp = pp->file + len - 1;
ret = e_snprintf(file, 32, "@%s", tmp + 1);
if (ret <= 0) if (ret <= 0)
goto error; goto error;
} }
if (pp->function) if (pp->function)
ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s", pp->function, ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
offs, pp->retprobe ? "%return" : "", line); offs, pp->retprobe ? "%return" : "", line,
file);
else else
ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", pp->file, line); ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
if (ret <= 0) if (ret <= 0)
goto error; goto error;
@ -511,15 +522,32 @@ void convert_to_perf_probe_event(struct kprobe_trace_event *tev,
{ {
char buf[64]; char buf[64];
int i; int i;
#ifndef NO_DWARF_SUPPORT
struct symbol *sym;
int fd, ret = 0;
pev->event = xstrdup(tev->event); sym = map__find_symbol_by_name(kmaps[MAP__FUNCTION],
pev->group = xstrdup(tev->group); tev->point.symbol, NULL);
if (sym) {
fd = open_vmlinux();
ret = find_perf_probe_point(fd, sym->start + tev->point.offset,
&pev->point);
close(fd);
}
if (ret <= 0) {
pev->point.function = xstrdup(tev->point.symbol);
pev->point.offset = tev->point.offset;
}
#else
/* Convert trace_point to probe_point */ /* Convert trace_point to probe_point */
pev->point.function = xstrdup(tev->point.symbol); pev->point.function = xstrdup(tev->point.symbol);
pev->point.offset = tev->point.offset; pev->point.offset = tev->point.offset;
#endif
pev->point.retprobe = tev->point.retprobe; pev->point.retprobe = tev->point.retprobe;
pev->event = xstrdup(tev->event);
pev->group = xstrdup(tev->group);
/* Convert trace_arg to probe_arg */ /* Convert trace_arg to probe_arg */
pev->nargs = tev->nargs; pev->nargs = tev->nargs;
pev->args = xzalloc(sizeof(struct perf_probe_arg) * pev->nargs); pev->args = xzalloc(sizeof(struct perf_probe_arg) * pev->nargs);
@ -650,7 +678,7 @@ static void show_perf_probe_event(struct perf_probe_event *pev)
ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event); ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event);
if (ret < 0) if (ret < 0)
die("Failed to copy event: %s", strerror(-ret)); die("Failed to copy event: %s", strerror(-ret));
printf(" %-40s (on %s", buf, place); printf(" %-20s (on %s", buf, place);
if (pev->nargs > 0) { if (pev->nargs > 0) {
printf(" with"); printf(" with");
@ -671,6 +699,7 @@ void show_perf_probe_events(void)
struct str_node *ent; struct str_node *ent;
setup_pager(); setup_pager();
init_vmlinux();
memset(&tev, 0, sizeof(tev)); memset(&tev, 0, sizeof(tev));
memset(&pev, 0, sizeof(pev)); memset(&pev, 0, sizeof(pev));

View File

@ -693,6 +693,76 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
return pf.ntevs; return pf.ntevs;
} }
/* Reverse search */
int find_perf_probe_point(int fd, unsigned long addr,
struct perf_probe_point *ppt)
{
Dwarf_Die cudie, spdie, indie;
Dwarf *dbg;
Dwarf_Line *line;
Dwarf_Addr laddr, eaddr;
const char *tmp;
int lineno, ret = 0;
dbg = dwarf_begin(fd, DWARF_C_READ);
if (!dbg)
return -ENOENT;
/* Find cu die */
if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr, &cudie))
return -EINVAL;
/* Find a corresponding line */
line = dwarf_getsrc_die(&cudie, (Dwarf_Addr)addr);
if (line) {
dwarf_lineaddr(line, &laddr);
if ((Dwarf_Addr)addr == laddr) {
dwarf_lineno(line, &lineno);
ppt->line = lineno;
tmp = dwarf_linesrc(line, NULL, NULL);
DIE_IF(!tmp);
ppt->file = xstrdup(tmp);
ret = 1;
}
}
/* Find a corresponding function */
if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) {
tmp = dwarf_diename(&spdie);
if (!tmp)
goto end;
dwarf_entrypc(&spdie, &eaddr);
if (!lineno) {
/* We don't have a line number, let's use offset */
ppt->function = xstrdup(tmp);
ppt->offset = addr - (unsigned long)eaddr;
ret = 1;
goto end;
}
if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr, &indie)) {
/* addr in an inline function */
tmp = dwarf_diename(&indie);
if (!tmp)
goto end;
dwarf_decl_line(&indie, &lineno);
} else {
if (eaddr == addr) /* No offset: function entry */
lineno = ppt->line;
else
dwarf_decl_line(&spdie, &lineno);
}
ppt->function = xstrdup(tmp);
ppt->line -= lineno; /* Make a relative line number */
}
end:
dwarf_end(dbg);
return ret;
}
/* Find line range from its line number */ /* Find line range from its line number */
static void find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf) static void find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
{ {

View File

@ -20,6 +20,10 @@ static inline int is_c_varname(const char *name)
extern int find_kprobe_trace_events(int fd, struct perf_probe_event *pev, extern int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
struct kprobe_trace_event **tevs); struct kprobe_trace_event **tevs);
/* Find a perf_probe_point from debuginfo */
extern int find_perf_probe_point(int fd, unsigned long addr,
struct perf_probe_point *ppt);
extern int find_line_range(int fd, struct line_range *lr); extern int find_line_range(int fd, struct line_range *lr);
#include <dwarf.h> #include <dwarf.h>