From 469b9b88488e89114bb3e9ac5ee7906b7b96123f Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Thu, 21 Oct 2010 19:13:41 +0900 Subject: perf probe: Add basic module support Add basic module probe support on perf probe. This introduces "--module " option to perf probe for putting probes and showing lines and variables in the given module. Currently, this supports only probing on running modules. Supporting off-line module probing is the next step. e.g.) [show lines] # ./perf probe --module drm -L drm_vblank_info 0 int drm_vblank_info(struct seq_file *m, void *data) 1 { struct drm_info_node *node = (struct drm_info_node *) m->private 3 struct drm_device *dev = node->minor->dev; ... [show vars] # ./perf probe --module drm -V drm_vblank_info:3 Available variables at drm_vblank_info:3 @ (unknown_type) data struct drm_info_node* node struct seq_file* m [put a probe] # ./perf probe --module drm drm_vblank_info:3 node m Add new event: probe:drm_vblank_info (on drm_vblank_info:3 with node m) You can now use it on all perf tools, such as: perf record -e probe:drm_vblank_info -aR sleep 1 [list probes] # ./perf probe -l probe:drm_vblank_info (on drm_vblank_info:3@drivers/gpu/drm/drm_info.c with ... Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Ingo Molnar Cc: Frederic Weisbecker LKML-Reference: <20101021101341.3542.71638.stgit@ltc236.sdl.hitachi.co.jp> Signed-off-by: Masami Hiramatsu Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/probe-event.c | 123 +++++++++++++++++++++++++++--------------- 1 file changed, 79 insertions(+), 44 deletions(-) (limited to 'tools/perf/util/probe-event.c') diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 82b0976e2053..3b6a5297bf16 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -74,10 +74,9 @@ static int e_snprintf(char *str, size_t size, const char *format, ...) static char *synthesize_perf_probe_point(struct perf_probe_point *pp); static struct machine machine; -/* Initialize symbol maps and path of vmlinux */ +/* Initialize symbol maps and path of vmlinux/modules */ static int init_vmlinux(void) { - struct dso *kernel; int ret; symbol_conf.sort_by_name = true; @@ -91,33 +90,61 @@ static int init_vmlinux(void) goto out; } - ret = machine__init(&machine, "/", 0); + ret = machine__init(&machine, "", HOST_KERNEL_ID); if (ret < 0) goto out; - kernel = dso__new_kernel(symbol_conf.vmlinux_name); - if (kernel == NULL) - die("Failed to create kernel dso."); - - ret = __machine__create_kernel_maps(&machine, kernel); - if (ret < 0) - pr_debug("Failed to create kernel maps.\n"); - + if (machine__create_kernel_maps(&machine) < 0) { + pr_debug("machine__create_kernel_maps "); + goto out; + } out: if (ret < 0) pr_warning("Failed to init vmlinux path.\n"); return ret; } +static struct symbol *__find_kernel_function_by_name(const char *name, + struct map **mapp) +{ + return machine__find_kernel_function_by_name(&machine, name, mapp, + NULL); +} + +const char *kernel_get_module_path(const char *module) +{ + struct dso *dso; + + if (module) { + list_for_each_entry(dso, &machine.kernel_dsos, node) { + if (strncmp(dso->short_name + 1, module, + dso->short_name_len - 2) == 0) + goto found; + } + pr_debug("Failed to find module %s.\n", module); + return NULL; + } else { + dso = machine.vmlinux_maps[MAP__FUNCTION]->dso; + if (dso__load_vmlinux_path(dso, + machine.vmlinux_maps[MAP__FUNCTION], NULL) < 0) { + pr_debug("Failed to load kernel map.\n"); + return NULL; + } + } +found: + return dso->long_name; +} + #ifdef DWARF_SUPPORT -static int open_vmlinux(void) +static int open_vmlinux(const char *module) { - if (map__load(machine.vmlinux_maps[MAP__FUNCTION], NULL) < 0) { - pr_debug("Failed to load kernel map.\n"); - return -EINVAL; + const char *path = kernel_get_module_path(module); + if (!path) { + pr_err("Failed to find path of %s module", module ?: "kernel"); + return -ENOENT; } - pr_debug("Try to open %s\n", machine.vmlinux_maps[MAP__FUNCTION]->dso->long_name); - return open(machine.vmlinux_maps[MAP__FUNCTION]->dso->long_name, O_RDONLY); + pr_debug("Try to open %s\n", path); + return open(path, O_RDONLY); } /* @@ -125,20 +152,19 @@ static int open_vmlinux(void) * Currently only handles kprobes. */ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp, - struct perf_probe_point *pp) + struct perf_probe_point *pp) { struct symbol *sym; - int fd, ret = -ENOENT; + struct map *map; + u64 addr; + int ret = -ENOENT; - sym = map__find_symbol_by_name(machine.vmlinux_maps[MAP__FUNCTION], - tp->symbol, NULL); + sym = __find_kernel_function_by_name(tp->symbol, &map); if (sym) { - fd = open_vmlinux(); - if (fd >= 0) { - ret = find_perf_probe_point(fd, - sym->start + tp->offset, pp); - close(fd); - } + addr = map->unmap_ip(map, sym->start + tp->offset); + pr_debug("try to find %s+%ld@%llx\n", tp->symbol, + tp->offset, addr); + ret = find_perf_probe_point((unsigned long)addr, pp); } if (ret <= 0) { pr_debug("Failed to find corresponding probes from " @@ -156,12 +182,12 @@ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp, /* Try to find perf_probe_event with debuginfo */ static int try_to_find_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs, - int max_tevs) + int max_tevs, const char *module) { bool need_dwarf = perf_probe_event_need_dwarf(pev); int fd, ntevs; - fd = open_vmlinux(); + fd = open_vmlinux(module); if (fd < 0) { if (need_dwarf) { pr_warning("Failed to open debuginfo file.\n"); @@ -300,7 +326,7 @@ error: * Show line-range always requires debuginfo to find source file and * line number. */ -int show_line_range(struct line_range *lr) +int show_line_range(struct line_range *lr, const char *module) { int l = 1; struct line_node *ln; @@ -313,7 +339,7 @@ int show_line_range(struct line_range *lr) if (ret < 0) return ret; - fd = open_vmlinux(); + fd = open_vmlinux(module); if (fd < 0) { pr_warning("Failed to open debuginfo file.\n"); return fd; @@ -421,7 +447,7 @@ static int show_available_vars_at(int fd, struct perf_probe_event *pev, /* Show available variables on given probe point */ int show_available_vars(struct perf_probe_event *pevs, int npevs, - int max_vls, bool externs) + int max_vls, const char *module, bool externs) { int i, fd, ret = 0; @@ -429,7 +455,7 @@ int show_available_vars(struct perf_probe_event *pevs, int npevs, if (ret < 0) return ret; - fd = open_vmlinux(); + fd = open_vmlinux(module); if (fd < 0) { pr_warning("Failed to open debuginfo file.\n"); return fd; @@ -447,8 +473,15 @@ int show_available_vars(struct perf_probe_event *pevs, int npevs, #else /* !DWARF_SUPPORT */ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp, - struct perf_probe_point *pp) + struct perf_probe_point *pp) { + struct symbol *sym; + + sym = __find_kernel_function_by_name(tp->symbol, NULL); + if (!sym) { + pr_err("Failed to find symbol %s in kernel.\n", tp->symbol); + return -ENOENT; + } pp->function = strdup(tp->symbol); if (pp->function == NULL) return -ENOMEM; @@ -460,7 +493,7 @@ static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp, static int try_to_find_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs __unused, - int max_tevs __unused) + int max_tevs __unused, const char *mod __unused) { if (perf_probe_event_need_dwarf(pev)) { pr_warning("Debuginfo-analysis is not supported.\n"); @@ -469,14 +502,15 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev, return 0; } -int show_line_range(struct line_range *lr __unused) +int show_line_range(struct line_range *lr __unused, const char *module __unused) { pr_warning("Debuginfo-analysis is not supported.\n"); return -ENOSYS; } int show_available_vars(struct perf_probe_event *pevs __unused, - int npevs __unused, int max_probe_points __unused) + int npevs __unused, int max_vls __unused, + const char *module __unused, bool externs __unused) { pr_warning("Debuginfo-analysis is not supported.\n"); return -ENOSYS; @@ -1159,7 +1193,7 @@ error: } static int convert_to_perf_probe_event(struct probe_trace_event *tev, - struct perf_probe_event *pev) + struct perf_probe_event *pev) { char buf[64] = ""; int i, ret; @@ -1588,14 +1622,14 @@ static int __add_probe_trace_events(struct perf_probe_event *pev, static int convert_to_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event **tevs, - int max_tevs) + int max_tevs, const char *module) { struct symbol *sym; int ret = 0, i; struct probe_trace_event *tev; /* Convert perf_probe_event with debuginfo */ - ret = try_to_find_probe_trace_events(pev, tevs, max_tevs); + ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, module); if (ret != 0) return ret; @@ -1644,8 +1678,7 @@ static int convert_to_probe_trace_events(struct perf_probe_event *pev, } /* Currently just checking function name from symbol map */ - sym = map__find_symbol_by_name(machine.vmlinux_maps[MAP__FUNCTION], - tev->point.symbol, NULL); + sym = __find_kernel_function_by_name(tev->point.symbol, NULL); if (!sym) { pr_warning("Kernel symbol \'%s\' not found.\n", tev->point.symbol); @@ -1668,7 +1701,7 @@ struct __event_package { }; int add_perf_probe_events(struct perf_probe_event *pevs, int npevs, - int max_tevs, bool force_add) + int max_tevs, const char *module, bool force_add) { int i, j, ret; struct __event_package *pkgs; @@ -1689,7 +1722,9 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs, pkgs[i].pev = &pevs[i]; /* Convert with or without debuginfo */ ret = convert_to_probe_trace_events(pkgs[i].pev, - &pkgs[i].tevs, max_tevs); + &pkgs[i].tevs, + max_tevs, + module); if (ret < 0) goto end; pkgs[i].ntevs = ret; -- cgit v1.2.3-59-g8ed1b