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perf probe: Move probe event utility functions to probe-event.c
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Split probe event (kprobe-events and perf probe events) utility
functions from builtin-probe.c to probe-event.c.

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091201001958.10235.90243.stgit@harusame>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Masami Hiramatsu authored and Ingo Molnar committed Dec 1, 2009
1 parent 934b1f5 commit 50656ee
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Showing 4 changed files with 294 additions and 218 deletions.
2 changes: 2 additions & 0 deletions tools/perf/Makefile
View file
Original file line number Diff line number Diff line change
Expand Up @@ -370,6 +370,7 @@ LIB_H += util/hist.h
LIB_H += util/thread.h
LIB_H += util/data_map.h
LIB_H += util/probe-finder.h
LIB_H += util/probe-event.h

LIB_OBJS += util/abspath.o
LIB_OBJS += util/alias.o
Expand Down Expand Up @@ -412,6 +413,7 @@ LIB_OBJS += util/svghelper.o
LIB_OBJS += util/sort.o
LIB_OBJS += util/hist.o
LIB_OBJS += util/data_map.o
LIB_OBJS += util/probe-event.o

BUILTIN_OBJS += builtin-annotate.o

Expand Down
227 changes: 9 additions & 218 deletions tools/perf/builtin-probe.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -40,6 +40,7 @@
#include "util/parse-options.h"
#include "util/parse-events.h" /* For debugfs_path */
#include "util/probe-finder.h"
#include "util/probe-event.h"

/* Default vmlinux search paths */
#define NR_SEARCH_PATH 3
Expand All @@ -51,8 +52,6 @@ const char *default_search_path[NR_SEARCH_PATH] = {

#define MAX_PATH_LEN 256
#define MAX_PROBES 128
#define MAX_PROBE_ARGS 128
#define PERFPROBE_GROUP "probe"

/* Session management structure */
static struct {
Expand All @@ -63,155 +62,17 @@ static struct {
struct probe_point probes[MAX_PROBES];
} session;

#define semantic_error(msg ...) die("Semantic error :" msg)

/* Parse probe point. Return 1 if return probe */
static void parse_probe_point(char *arg, struct probe_point *pp)
{
char *ptr, *tmp;
char c, nc = 0;
/*
* <Syntax>
* perf probe SRC:LN
* perf probe FUNC[+OFFS|%return][@SRC]
*/

ptr = strpbrk(arg, ":+@%");
if (ptr) {
nc = *ptr;
*ptr++ = '\0';
}

/* Check arg is function or file and copy it */
if (strchr(arg, '.')) /* File */
pp->file = strdup(arg);
else /* Function */
pp->function = strdup(arg);
DIE_IF(pp->file == NULL && pp->function == NULL);

/* Parse other options */
while (ptr) {
arg = ptr;
c = nc;
ptr = strpbrk(arg, ":+@%");
if (ptr) {
nc = *ptr;
*ptr++ = '\0';
}
switch (c) {
case ':': /* Line number */
pp->line = strtoul(arg, &tmp, 0);
if (*tmp != '\0')
semantic_error("There is non-digit charactor"
" in line number.");
break;
case '+': /* Byte offset from a symbol */
pp->offset = strtoul(arg, &tmp, 0);
if (*tmp != '\0')
semantic_error("There is non-digit charactor"
" in offset.");
break;
case '@': /* File name */
if (pp->file)
semantic_error("SRC@SRC is not allowed.");
pp->file = strdup(arg);
DIE_IF(pp->file == NULL);
if (ptr)
semantic_error("@SRC must be the last "
"option.");
break;
case '%': /* Probe places */
if (strcmp(arg, "return") == 0) {
pp->retprobe = 1;
} else /* Others not supported yet */
semantic_error("%%%s is not supported.", arg);
break;
default:
DIE_IF("Program has a bug.");
break;
}
}

/* Exclusion check */
if (pp->line && pp->offset)
semantic_error("Offset can't be used with line number.");
if (!pp->line && pp->file && !pp->function)
semantic_error("File always requires line number.");
if (pp->offset && !pp->function)
semantic_error("Offset requires an entry function.");
if (pp->retprobe && !pp->function)
semantic_error("Return probe requires an entry function.");
if ((pp->offset || pp->line) && pp->retprobe)
semantic_error("Offset/Line can't be used with return probe.");

pr_debug("symbol:%s file:%s line:%d offset:%d, return:%d\n",
pp->function, pp->file, pp->line, pp->offset, pp->retprobe);
}

/* Parse an event definition. Note that any error must die. */
static void parse_probe_event(const char *str)
{
char *argv[MAX_PROBE_ARGS + 1]; /* probe + args */
int argc, i;
struct probe_point *pp = &session.probes[session.nr_probe];

pr_debug("probe-definition(%d): %s\n", session.nr_probe, str);
if (++session.nr_probe == MAX_PROBES)
semantic_error("Too many probes");

/* Separate arguments, similar to argv_split */
argc = 0;
do {
/* Skip separators */
while (isspace(*str))
str++;

/* Add an argument */
if (*str != '\0') {
const char *s = str;
/* Check the limit number of arguments */
if (argc == MAX_PROBE_ARGS + 1)
semantic_error("Too many arguments");

/* Skip the argument */
while (!isspace(*str) && *str != '\0')
str++;

/* Duplicate the argument */
argv[argc] = strndup(s, str - s);
if (argv[argc] == NULL)
die("strndup");
pr_debug("argv[%d]=%s\n", argc, argv[argc]);
argc++;

}
} while (*str != '\0');
if (!argc)
semantic_error("An empty argument.");

/* Parse probe point */
parse_probe_point(argv[0], pp);
free(argv[0]);
if (pp->file || pp->line)
session.need_dwarf = 1;

/* Copy arguments */
pp->nr_args = argc - 1;
if (pp->nr_args > 0) {
pp->args = (char **)malloc(sizeof(char *) * pp->nr_args);
if (!pp->args)
die("malloc");
memcpy(pp->args, &argv[1], sizeof(char *) * pp->nr_args);
}
die("Too many probes (> %d) are specified.", MAX_PROBES);

/* Ensure return probe has no C argument */
for (i = 0; i < pp->nr_args; i++)
if (is_c_varname(pp->args[i])) {
if (pp->retprobe)
semantic_error("You can't specify local"
" variable for kretprobe");
session.need_dwarf = 1;
}
/* Parse perf-probe event into probe_point */
session.need_dwarf = parse_perf_probe_event(str, pp);

pr_debug("%d arguments\n", pp->nr_args);
}
Expand Down Expand Up @@ -288,59 +149,15 @@ static const struct option options[] = {
"\t\tALN:\tAbsolute line number in file.\n"
"\t\tARG:\tProbe argument (local variable name or\n"
#endif
"\t\t\tkprobe-tracer argument format is supported.)\n",
"\t\t\tkprobe-tracer argument format.)\n",
opt_add_probe_event),
OPT_END()
};

static int write_new_event(int fd, const char *buf)
{
int ret;

ret = write(fd, buf, strlen(buf));
if (ret <= 0)
die("Failed to create event.");
else
printf("Added new event: %s\n", buf);

return ret;
}

#define MAX_CMDLEN 256

static int synthesize_probe_event(struct probe_point *pp)
{
char *buf;
int i, len, ret;
pp->probes[0] = buf = zalloc(MAX_CMDLEN);
if (!buf)
die("Failed to allocate memory by zalloc.");
ret = snprintf(buf, MAX_CMDLEN, "%s+%d", pp->function, pp->offset);
if (ret <= 0 || ret >= MAX_CMDLEN)
goto error;
len = ret;

for (i = 0; i < pp->nr_args; i++) {
ret = snprintf(&buf[len], MAX_CMDLEN - len, " %s",
pp->args[i]);
if (ret <= 0 || ret >= MAX_CMDLEN - len)
goto error;
len += ret;
}
pp->found = 1;
return pp->found;
error:
free(pp->probes[0]);
if (ret > 0)
ret = -E2BIG;
return ret;
}

int cmd_probe(int argc, const char **argv, const char *prefix __used)
{
int i, j, fd, ret;
struct probe_point *pp;
char buf[MAX_CMDLEN];

argc = parse_options(argc, argv, options, probe_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
Expand All @@ -352,7 +169,7 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)

if (session.need_dwarf)
#ifdef NO_LIBDWARF
semantic_error("Debuginfo-analysis is not supported");
die("Debuginfo-analysis is not supported");
#else /* !NO_LIBDWARF */
pr_debug("Some probes require debuginfo.\n");

Expand Down Expand Up @@ -398,41 +215,15 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
if (pp->found) /* This probe is already found. */
continue;

ret = synthesize_probe_event(pp);
ret = synthesize_trace_kprobe_event(pp);
if (ret == -E2BIG)
semantic_error("probe point is too long.");
die("probe point definition becomes too long.");
else if (ret < 0)
die("Failed to synthesize a probe point.");
}

/* Settng up probe points */
snprintf(buf, MAX_CMDLEN, "%s/../kprobe_events", debugfs_path);
fd = open(buf, O_WRONLY, O_APPEND);
if (fd < 0) {
if (errno == ENOENT)
die("kprobe_events file does not exist - please rebuild with CONFIG_KPROBE_TRACER.");
else
die("Could not open kprobe_events file: %s",
strerror(errno));
}
for (j = 0; j < session.nr_probe; j++) {
pp = &session.probes[j];
if (pp->found == 1) {
snprintf(buf, MAX_CMDLEN, "%c:%s/%s_%x %s\n",
pp->retprobe ? 'r' : 'p', PERFPROBE_GROUP,
pp->function, pp->offset, pp->probes[0]);
write_new_event(fd, buf);
} else
for (i = 0; i < pp->found; i++) {
snprintf(buf, MAX_CMDLEN, "%c:%s/%s_%x_%d %s\n",
pp->retprobe ? 'r' : 'p',
PERFPROBE_GROUP,
pp->function, pp->offset, i,
pp->probes[i]);
write_new_event(fd, buf);
}
}
close(fd);
add_trace_kprobe_events(session.probes, session.nr_probe);
return 0;
}

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