lkml.org 
[lkml]   [2010]   [Mar]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH -tip 09/10] perf probe: List probes with line number and file name
Date
Improve --list to show current exist probes with line number and file name.
This enables user easily to check which line is already probed.

e.g.
./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: Ingo Molnar <mingo@elte.hu>
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>
---
tools/perf/util/probe-event.c | 55 ++++++++++++++++++++++++-------
tools/perf/util/probe-finder.c | 70 ++++++++++++++++++++++++++++++++++++++++
tools/perf/util/probe-finder.h | 4 ++
3 files changed, 116 insertions(+), 13 deletions(-)
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index b44ddfb..4e3c1ae 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -70,7 +70,6 @@ static int e_snprintf(char *str, size_t size, const char *format, ...)
return ret;
}

-
static struct map_groups kmap_groups;
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) */
static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
{
- char *buf;
- char offs[64] = "", line[64] = "";
- int ret;
+ char *buf, *tmp;
+ char offs[32] = "", line[32] = "", file[32] = "";
+ int ret, len;

buf = xzalloc(MAX_CMDLEN);
if (pp->offset) {
- ret = e_snprintf(offs, 64, "+%lu", pp->offset);
+ ret = e_snprintf(offs, 32, "+%lu", pp->offset);
if (ret <= 0)
goto error;
}
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)
goto error;
}

if (pp->function)
- ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s", pp->function,
- offs, pp->retprobe ? "%return" : "", line);
+ ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
+ offs, pp->retprobe ? "%return" : "", line,
+ file);
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)
goto error;

@@ -511,15 +522,32 @@ void convert_to_perf_probe_event(struct kprobe_trace_event *tev,
{
char buf[64];
int i;
+#ifndef NO_DWARF_SUPPORT
+ struct symbol *sym;
+ int fd, ret = 0;

- pev->event = xstrdup(tev->event);
- pev->group = xstrdup(tev->group);
-
+ sym = map__find_symbol_by_name(kmaps[MAP__FUNCTION],
+ 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 */
pev->point.function = xstrdup(tev->point.symbol);
pev->point.offset = tev->point.offset;
+#endif
pev->point.retprobe = tev->point.retprobe;

+ pev->event = xstrdup(tev->event);
+ pev->group = xstrdup(tev->group);
+
/* Convert trace_arg to probe_arg */
pev->nargs = tev->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);
if (ret < 0)
die("Failed to copy event: %s", strerror(-ret));
- printf(" %-40s (on %s", buf, place);
+ printf(" %-20s (on %s", buf, place);

if (pev->nargs > 0) {
printf(" with");
@@ -671,6 +699,7 @@ void show_perf_probe_events(void)
struct str_node *ent;

setup_pager();
+ init_vmlinux();

memset(&tev, 0, sizeof(tev));
memset(&pev, 0, sizeof(pev));
diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
index 251b4c4..e02b607 100644
--- a/tools/perf/util/probe-finder.c
+++ b/tools/perf/util/probe-finder.c
@@ -693,6 +693,76 @@ int find_kprobe_trace_events(int fd, struct perf_probe_event *pev,
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 */
static void find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
{
diff --git a/tools/perf/util/probe-finder.h b/tools/perf/util/probe-finder.h
index 4949526..2f2307d 100644
--- a/tools/perf/util/probe-finder.h
+++ b/tools/perf/util/probe-finder.h
@@ -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,
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);

#include <dwarf.h>

--
Masami Hiramatsu
e-mail: mhiramat@redhat.com


\
 
 \ /
  Last update: 2010-03-16 23:01    [from the cache]
©2003-2011 Jasper Spaans