perf probe: Add perf probe command support without libdwarf (23e8ec0d) · Commits · 戴 / test

tools/perf/Makefile

+3 −3

Original line number	Diff line number	Diff line
		@@ -385,6 +385,7 @@ BUILTIN_OBJS += builtin-stat.o
		BUILTIN_OBJS += builtin-timechart.o
		BUILTIN_OBJS += builtin-top.o
		BUILTIN_OBJS += builtin-trace.o
		BUILTIN_OBJS += builtin-probe.o

		PERFLIBS = $(LIB_FILE)

		@@ -420,13 +421,12 @@ ifneq ($(shell sh -c "(echo '\#include <libelf.h>'; echo 'int main(void) { Elf *
		endif

		ifneq ($(shell sh -c "(echo '\#include <libdwarf/dwarf.h>'; echo '\#include <libdwarf/libdwarf.h>'; echo 'int main(void) { Dwarf_Debug dbg; Dwarf_Error err; dwarf_init(0, DW_DLC_READ, 0, 0, &dbg, &err); return (long)dbg; }') \| $(CC) -x c - $(ALL_CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -ldwarf -lelf -o /dev/null $(ALL_LDFLAGS) > /dev/null 2>&1 && echo y"), y)
		msg := $(warning No libdwarf.h found, disables probe subcommand. Please install libdwarf-dev/libdwarf-devel);
		msg := $(warning No libdwarf.h found, disables dwarf support. Please install libdwarf-dev/libdwarf-devel);
		BASIC_CFLAGS += -DNO_LIBDWARF
		else
		EXTLIBS += -lelf -ldwarf
		LIB_H += util/probe-finder.h
		LIB_OBJS += util/probe-finder.o
		BUILTIN_OBJS += builtin-probe.o
		BASIC_CFLAGS += -DSUPPORT_DWARF
		endif

		ifdef NO_DEMANGLE

tools/perf/builtin-probe.c

+35 −7

Original line number	Diff line number	Diff line
		@@ -54,6 +54,7 @@ const char *default_search_path[NR_SEARCH_PATH] = {
		static struct {
		char *vmlinux;
		char *release;
		int need_dwarf;
		int nr_probe;
		struct probe_point probes[MAX_PROBES];
		char *events[MAX_PROBES];
		@@ -162,6 +163,8 @@ static int parse_probepoint(const struct option *opt __used,
		pp->function, pp->file, pp->offset);
		}
		free(argv[1]);
		if (pp->file)
		session.need_dwarf = 1;

		/* Copy arguments */
		pp->nr_args = argc - 2;
		@@ -173,15 +176,19 @@ static int parse_probepoint(const struct option *opt __used,
		}

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

		debug("%d arguments\n", pp->nr_args);
		return 0;
		}

		#ifndef NO_LIBDWARF
		static int open_default_vmlinux(void)
		{
		struct utsname uts;
		@@ -209,6 +216,7 @@ static int open_default_vmlinux(void)
		}
		return fd;
		}
		#endif

		static const char * const probe_usage[] = {
		"perf probe [<options>] -P 'PROBEDEF' [-P 'PROBEDEF' ...]",
		@@ -216,10 +224,16 @@ static const char * const probe_usage[] = {
		};

		static const struct option options[] = {
		#ifndef NO_LIBDWARF
		OPT_STRING('k', "vmlinux", &session.vmlinux, "file",
		"vmlinux/module pathname"),
		#endif
		OPT_CALLBACK('P', "probe", NULL,
		#ifdef NO_LIBDWARF
		"p\|r:[GRP/]NAME FUNC[+OFFS] [ARG ...]",
		#else
		"p\|r:[GRP/]NAME FUNC[+OFFS][@SRC]\|@SRC:LINE [ARG ...]",
		#endif
		"probe point definition, where\n"
		"\t\tp:\tkprobe probe\n"
		"\t\tr:\tkretprobe probe\n"
		@@ -227,9 +241,13 @@ static const struct option options[] = {
		"\t\tNAME:\tEvent name\n"
		"\t\tFUNC:\tFunction name\n"
		"\t\tOFFS:\tOffset from function entry (in byte)\n"
		#ifdef NO_LIBDWARF
		"\t\tARG:\tProbe argument (only \n"
		#else
		"\t\tSRC:\tSource code path\n"
		"\t\tLINE:\tLine number\n"
		"\t\tARG:\tProbe argument (local variable name or\n"
		#endif
		"\t\t\tkprobe-tracer argument format is supported.)\n",
		parse_probepoint),
		OPT_END()
		@@ -279,7 +297,7 @@ error:

		int cmd_probe(int argc, const char *argv, const char prefix __used)
		{
		int i, j, fd, ret, need_dwarf = 0;
		int i, j, fd, ret;
		struct probe_point *pp;
		char buf[MAX_CMDLEN];

		@@ -288,12 +306,19 @@ int cmd_probe(int argc, const char *argv, const char prefix __used)
		if (argc \|\| session.nr_probe == 0)
		usage_with_options(probe_usage, options);

		/* Synthesize return probes */
		#ifdef NO_LIBDWARF
		if (session.need_dwarf)
		semantic_error("Dwarf-analysis is not supported");
		#endif

		/* Synthesize probes without dwarf */
		for (j = 0; j < session.nr_probe; j++) {
		#ifndef NO_LIBDWARF
		if (session.events[j][0] != 'r') {
		need_dwarf = 1;
		session.need_dwarf = 1;
		continue;
		}
		#endif
		ret = synthesize_probepoint(&session.probes[j]);
		if (ret == -E2BIG)
		semantic_error("probe point is too long.");
		@@ -303,7 +328,8 @@ int cmd_probe(int argc, const char *argv, const char prefix __used)
		}
		}

		if (!need_dwarf)
		#ifndef NO_LIBDWARF
		if (!session.need_dwarf)
		goto setup_probes;

		if (session.vmlinux)
		@@ -332,6 +358,8 @@ int cmd_probe(int argc, const char *argv, const char prefix __used)
		close(fd);

		setup_probes:
		#endif /* !NO_LIBDWARF */

		/* Settng up probe points */
		snprintf(buf, MAX_CMDLEN, "%s/../kprobe_events", debugfs_path);
		fd = open(buf, O_WRONLY, O_APPEND);

tools/perf/perf.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -295,9 +295,7 @@ static void handle_internal_command(int argc, const char **argv)
		{ "version", cmd_version, 0 },
		{ "trace", cmd_trace, 0 },
		{ "sched", cmd_sched, 0 },
		#ifdef SUPPORT_DWARF
		{ "probe", cmd_probe, 0 },
		#endif
		};
		unsigned int i;
		static const char ext[] = STRIP_EXTENSION;

tools/perf/util/probe-finder.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -44,6 +44,7 @@ struct probe_point {
		char probes[MAX_PROBES]; / Output buffers (will be allocated)*/
		};

		#ifndef NO_LIBDWARF
		extern int find_probepoint(int fd, struct probe_point *pp);

		#include <libdwarf/dwarf.h>
		@@ -64,5 +65,6 @@ struct probe_finder {
		char buf; / Current output buffer */
		int len; /* Length of output buffer */
		};
		#endif /* NO_LIBDWARF */

		#endif /_PROBE_FINDER_H /

Admin message