From 253977b0d87fbb793f12b1661a763ae264028ccf Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 27 Oct 2009 16:43:10 -0400 Subject: [PATCH] perf/probes: Improve probe point syntax of perf-probe This changes probe point syntax of perf-probe as below [:ABS_LN] [ARGS] or [+OFFS|%return][@SRC] [ARGS] And event name and event group name are automatically generated based on probe-symbol and offset as below. perfprobes/SYMBOL_OFFSET[_NUM] Where SYMBOL is the probing symbol and OFFSET is the byte offset from the symbol. Signed-off-by: Masami Hiramatsu Cc: Steven Rostedt Cc: Jim Keniston Cc: Ananth N Mavinakayanahalli Cc: Christoph Hellwig Cc: Frank Ch. Eigler Cc: Frederic Weisbecker Cc: Jason Baron Cc: K.Prasad Cc: Peter Zijlstra Cc: Srikar Dronamraju LKML-Reference: <20091027204310.30545.84984.stgit@harusame> Signed-off-by: Ingo Molnar --- tools/perf/builtin-probe.c | 181 ++++++++++++++++++++------------- tools/perf/util/probe-finder.c | 10 ++ tools/perf/util/probe-finder.h | 2 + 3 files changed, 123 insertions(+), 70 deletions(-) diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c index 3370dabed15d..92b4c491f23d 100644 --- a/tools/perf/builtin-probe.c +++ b/tools/perf/builtin-probe.c @@ -52,6 +52,7 @@ 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 "perfprobe" /* Session management structure */ static struct { @@ -60,20 +61,100 @@ static struct { int need_dwarf; int nr_probe; struct probe_point probes[MAX_PROBES]; - char *events[MAX_PROBES]; } session; #define semantic_error(msg ...) die("Semantic error :" msg) -/* Parse a probe point. Note that any error must die. */ -static void parse_probepoint(const char *str) +/* 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; + /* + * + * 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->function) + semantic_error("Function-relative line number is not" + " supported yet."); + 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->retprobe) + semantic_error("Offset 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 + 2]; /* Event + probe + args */ int argc, i; - char *arg, *ptr; struct probe_point *pp = &session.probes[session.nr_probe]; - char **event = &session.events[session.nr_probe]; - int retp = 0; pr_debug("probe-definition(%d): %s\n", session.nr_probe, str); if (++session.nr_probe == MAX_PROBES) @@ -103,70 +184,28 @@ static void parse_probepoint(const char *str) pr_debug("argv[%d]=%s\n", argc, argv[argc - 1]); } } while (*str != '\0'); - if (argc < 2) - semantic_error("Need event-name and probe-point at least."); - - /* Parse the event name */ - if (argv[0][0] == 'r') - retp = 1; - else if (argv[0][0] != 'p') - semantic_error("You must specify 'p'(kprobe) or" - " 'r'(kretprobe) first."); - /* TODO: check event name */ - *event = argv[0]; + if (!argc) + semantic_error("An empty argument."); /* Parse probe point */ - arg = argv[1]; - if (arg[0] == '@') { - /* Source Line */ - arg++; - ptr = strchr(arg, ':'); - if (!ptr || !isdigit(ptr[1])) - semantic_error("Line number is required."); - *ptr++ = '\0'; - if (strlen(arg) == 0) - semantic_error("No file name."); - pp->file = strdup(arg); - pp->line = atoi(ptr); - if (!pp->file || !pp->line) - semantic_error("Failed to parse line."); - pr_debug("file:%s line:%d\n", pp->file, pp->line); - } else { - /* Function name */ - ptr = strchr(arg, '+'); - if (ptr) { - if (!isdigit(ptr[1])) - semantic_error("Offset is required."); - *ptr++ = '\0'; - pp->offset = atoi(ptr); - } else - ptr = arg; - ptr = strchr(ptr, '@'); - if (ptr) { - *ptr++ = '\0'; - pp->file = strdup(ptr); - } - pp->function = strdup(arg); - pr_debug("symbol:%s file:%s offset:%d\n", - pp->function, pp->file, pp->offset); - } - free(argv[1]); + parse_probe_point(argv[0], pp); + free(argv[0]); if (pp->file) session.need_dwarf = 1; /* Copy arguments */ - pp->nr_args = argc - 2; + 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[2], sizeof(char *) * pp->nr_args); + memcpy(pp->args, &argv[1], sizeof(char *) * pp->nr_args); } /* Ensure return probe has no C argument */ for (i = 0; i < pp->nr_args; i++) if (is_c_varname(pp->args[i])) { - if (retp) + if (pp->retprobe) semantic_error("You can't specify local" " variable for kretprobe"); session.need_dwarf = 1; @@ -175,11 +214,11 @@ static void parse_probepoint(const char *str) pr_debug("%d arguments\n", pp->nr_args); } -static int opt_add_probepoint(const struct option *opt __used, +static int opt_add_probe_event(const struct option *opt __used, const char *str, int unset __used) { if (str) - parse_probepoint(str); + parse_probe_event(str); return 0; } @@ -229,17 +268,16 @@ static const struct option options[] = { #endif OPT_CALLBACK('a', "add", NULL, #ifdef NO_LIBDWARF - "p|r:[GRP/]NAME FUNC[+OFFS] [ARG ...]", + "FUNC[+OFFS|%return] [ARG ...]", #else - "p|r:[GRP/]NAME FUNC[+OFFS][@SRC]|@SRC:LINE [ARG ...]", + "FUNC[+OFFS|%return][@SRC]|SRC:LINE [ARG ...]", #endif "probe point definition, where\n" - "\t\tp:\tkprobe probe\n" - "\t\tr:\tkretprobe probe\n" "\t\tGRP:\tGroup name (optional)\n" "\t\tNAME:\tEvent name\n" "\t\tFUNC:\tFunction name\n" "\t\tOFFS:\tOffset from function entry (in byte)\n" + "\t\t%return:\tPut the probe at function return\n" #ifdef NO_LIBDWARF "\t\tARG:\tProbe argument (only \n" #else @@ -248,7 +286,7 @@ static const struct option options[] = { "\t\tARG:\tProbe argument (local variable name or\n" #endif "\t\t\tkprobe-tracer argument format is supported.)\n", - opt_add_probepoint), + opt_add_probe_event), OPT_END() }; @@ -266,7 +304,7 @@ static int write_new_event(int fd, const char *buf) #define MAX_CMDLEN 256 -static int synthesize_probepoint(struct probe_point *pp) +static int synthesize_probe_event(struct probe_point *pp) { char *buf; int i, len, ret; @@ -316,12 +354,12 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used) /* Synthesize probes without dwarf */ for (j = 0; j < session.nr_probe; j++) { #ifndef NO_LIBDWARF - if (session.events[j][0] != 'r') { + if (!session.probes[j].retprobe) { session.need_dwarf = 1; continue; } #endif - ret = synthesize_probepoint(&session.probes[j]); + ret = synthesize_probe_event(&session.probes[j]); if (ret == -E2BIG) semantic_error("probe point is too long."); else if (ret < 0) @@ -349,7 +387,6 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used) ret = find_probepoint(fd, pp); if (ret <= 0) die("No probe point found.\n"); - pr_debug("probe event %s found\n", session.events[j]); } close(fd); @@ -364,13 +401,17 @@ setup_probes: for (j = 0; j < session.nr_probe; j++) { pp = &session.probes[j]; if (pp->found == 1) { - snprintf(buf, MAX_CMDLEN, "%s %s\n", - session.events[j], pp->probes[0]); + 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, "%s%d %s\n", - session.events[j], i, pp->probes[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[0]); write_new_event(fd, buf); } } diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c index b98d35ef7116..6d3bac9f9473 100644 --- a/tools/perf/util/probe-finder.c +++ b/tools/perf/util/probe-finder.c @@ -483,10 +483,20 @@ static void show_probepoint(Dwarf_Die sp_die, Dwarf_Signed offs, if (ret == DW_DLV_OK) { ret = snprintf(tmp, MAX_PROBE_BUFFER, "%s+%u", name, (unsigned int)offs); + /* Copy the function name if possible */ + if (!pp->function) { + pp->function = strdup(name); + pp->offset = offs; + } dwarf_dealloc(__dw_debug, name, DW_DLA_STRING); } else { /* This function has no name. */ ret = snprintf(tmp, MAX_PROBE_BUFFER, "0x%llx", pf->addr); + if (!pp->function) { + /* TODO: Use _stext */ + pp->function = strdup(""); + pp->offset = (int)pf->addr; + } } DIE_IF(ret < 0); DIE_IF(ret >= MAX_PROBE_BUFFER); diff --git a/tools/perf/util/probe-finder.h b/tools/perf/util/probe-finder.h index d17fafc21351..240d6cb3cc2e 100644 --- a/tools/perf/util/probe-finder.h +++ b/tools/perf/util/probe-finder.h @@ -22,6 +22,8 @@ struct probe_point { int nr_args; /* Number of arguments */ char **args; /* Arguments */ + int retprobe; /* Return probe */ + /* Output */ int found; /* Number of found probe points */ char *probes[MAX_PROBES]; /* Output buffers (will be allocated)*/ -- 2.20.1