diff options
author | Krister Johansen <kjlx@templeofstupid.com> | 2017-07-05 18:48:10 -0700 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2017-07-18 23:14:10 -0300 |
commit | 544abd44c7064c8a58a6bd2073d757f6b91d98c5 (patch) | |
tree | faa9e5d4c4b86067f4b5cd9f8200010a726a314d /tools/perf | |
parent | bf2e710b3cb8445c052f2ff50b4875a2523bb279 (diff) | |
download | linux-stable-544abd44c7064c8a58a6bd2073d757f6b91d98c5.tar.gz linux-stable-544abd44c7064c8a58a6bd2073d757f6b91d98c5.tar.bz2 linux-stable-544abd44c7064c8a58a6bd2073d757f6b91d98c5.zip |
perf probe: Allow placing uprobes in alternate namespaces.
Teaches perf how to place a uprobe on a file that's in a different mount
namespace. The user must add the probe using the --target-ns argument
to perf probe. Once it has been placed, it may be recorded against
without further namespace-specific commands.
Signed-off-by: Krister Johansen <kjlx@templeofstupid.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
[ PPC build fixed by Ravi: ]
Link: http://lkml.kernel.org/r/1500287542-6219-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com
Cc: Thomas-Mich Richter <tmricht@linux.vnet.ibm.com>
[ Fix !HAVE_DWARF_SUPPORT build ]
Link: http://lkml.kernel.org/r/1499305693-1599-4-git-send-email-kjlx@templeofstupid.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf')
-rw-r--r-- | tools/perf/Documentation/perf-probe.txt | 9 | ||||
-rw-r--r-- | tools/perf/arch/powerpc/util/sym-handling.c | 2 | ||||
-rw-r--r-- | tools/perf/builtin-probe.c | 43 | ||||
-rw-r--r-- | tools/perf/util/namespaces.c | 13 | ||||
-rw-r--r-- | tools/perf/util/namespaces.h | 2 | ||||
-rw-r--r-- | tools/perf/util/probe-event.c | 80 | ||||
-rw-r--r-- | tools/perf/util/probe-event.h | 10 |
7 files changed, 125 insertions, 34 deletions
diff --git a/tools/perf/Documentation/perf-probe.txt b/tools/perf/Documentation/perf-probe.txt index 165c2b1d4317..a42aabc2b082 100644 --- a/tools/perf/Documentation/perf-probe.txt +++ b/tools/perf/Documentation/perf-probe.txt @@ -130,6 +130,11 @@ OPTIONS --max-probes=NUM:: Set the maximum number of probe points for an event. Default is 128. +--target-ns=PID: + Obtain mount namespace information from the target pid. This is + used when creating a uprobe for a process that resides in a + different mount namespace from the perf(1) utility. + -x:: --exec=PATH:: Specify path to the executable or shared library file for user @@ -264,6 +269,10 @@ Add probes at malloc() function on libc ./perf probe -x /lib/libc.so.6 malloc or ./perf probe /lib/libc.so.6 malloc +Add a uprobe to a target process running in a different mount namespace + + ./perf probe --target-ns <target pid> -x /lib64/libc.so.6 malloc + SEE ALSO -------- linkperf:perf-trace[1], linkperf:perf-record[1], linkperf:perf-buildid-cache[1] diff --git a/tools/perf/arch/powerpc/util/sym-handling.c b/tools/perf/arch/powerpc/util/sym-handling.c index bf9a2594572c..9c4e23d8c8ce 100644 --- a/tools/perf/arch/powerpc/util/sym-handling.c +++ b/tools/perf/arch/powerpc/util/sym-handling.c @@ -126,7 +126,7 @@ void arch__post_process_probe_trace_events(struct perf_probe_event *pev, struct rb_node *tmp; int i = 0; - map = get_target_map(pev->target, pev->uprobes); + map = get_target_map(pev->target, pev->nsi, pev->uprobes); if (!map || map__load(map) < 0) return; diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c index cf9f9e9c2fc0..3fb98d59cd27 100644 --- a/tools/perf/builtin-probe.c +++ b/tools/perf/builtin-probe.c @@ -58,6 +58,7 @@ static struct { struct line_range line_range; char *target; struct strfilter *filter; + struct nsinfo *nsi; } params; /* Parse an event definition. Note that any error must die. */ @@ -80,6 +81,9 @@ static int parse_probe_event(const char *str) params.target_used = true; } + if (params.nsi) + pev->nsi = nsinfo__get(params.nsi); + /* Parse a perf-probe command into event */ ret = parse_perf_probe_command(str, pev); pr_debug("%d arguments\n", pev->nargs); @@ -189,7 +193,7 @@ static int opt_set_target(const struct option *opt, const char *str, /* Expand given path to absolute path, except for modulename */ if (params.uprobes || strchr(str, '/')) { - tmp = realpath(str, NULL); + tmp = nsinfo__realpath(str, params.nsi); if (!tmp) { pr_warning("Failed to get the absolute path of %s: %m\n", str); return ret; @@ -208,6 +212,34 @@ static int opt_set_target(const struct option *opt, const char *str, return ret; } +static int opt_set_target_ns(const struct option *opt __maybe_unused, + const char *str, int unset __maybe_unused) +{ + int ret = -ENOENT; + pid_t ns_pid; + struct nsinfo *nsip; + + if (str) { + errno = 0; + ns_pid = (pid_t)strtol(str, NULL, 10); + if (errno != 0) { + ret = -errno; + pr_warning("Failed to parse %s as a pid: %s\n", str, + strerror(errno)); + return ret; + } + nsip = nsinfo__new(ns_pid); + if (nsip && nsip->need_setns) + params.nsi = nsinfo__get(nsip); + nsinfo__put(nsip); + + ret = 0; + } + + return ret; +} + + /* Command option callbacks */ #ifdef HAVE_DWARF_SUPPORT @@ -299,6 +331,7 @@ static void cleanup_params(void) line_range__clear(¶ms.line_range); free(params.target); strfilter__delete(params.filter); + nsinfo__put(params.nsi); memset(¶ms, 0, sizeof(params)); } @@ -554,6 +587,8 @@ __cmd_probe(int argc, const char **argv) OPT_BOOLEAN(0, "cache", &probe_conf.cache, "Manipulate probe cache"), OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory", "Look for files with symbols relative to this directory"), + OPT_CALLBACK(0, "target-ns", NULL, "pid", + "target pid for namespace contexts", opt_set_target_ns), OPT_END() }; int ret; @@ -634,15 +669,15 @@ __cmd_probe(int argc, const char **argv) pr_err_with_code(" Error: Failed to show event list.", ret); return ret; case 'F': - ret = show_available_funcs(params.target, params.filter, - params.uprobes); + ret = show_available_funcs(params.target, params.nsi, + params.filter, params.uprobes); if (ret < 0) pr_err_with_code(" Error: Failed to show functions.", ret); return ret; #ifdef HAVE_DWARF_SUPPORT case 'L': ret = show_line_range(¶ms.line_range, params.target, - params.uprobes); + params.nsi, params.uprobes); if (ret < 0) pr_err_with_code(" Error: Failed to show lines.", ret); return ret; diff --git a/tools/perf/util/namespaces.c b/tools/perf/util/namespaces.c index fc5f398779a4..a58e91197729 100644 --- a/tools/perf/util/namespaces.c +++ b/tools/perf/util/namespaces.c @@ -11,6 +11,7 @@ #include "event.h" #include <sys/types.h> #include <sys/stat.h> +#include <limits.h> #include <sched.h> #include <stdlib.h> #include <stdio.h> @@ -233,3 +234,15 @@ void nsinfo__mountns_exit(struct nscookie *nc) nc->newns = -1; } } + +char *nsinfo__realpath(const char *path, struct nsinfo *nsi) +{ + char *rpath; + struct nscookie nsc; + + nsinfo__mountns_enter(nsi, &nsc); + rpath = realpath(path, NULL); + nsinfo__mountns_exit(&nsc); + + return rpath; +} diff --git a/tools/perf/util/namespaces.h b/tools/perf/util/namespaces.h index f19aa41119ae..05d82601c9a6 100644 --- a/tools/perf/util/namespaces.h +++ b/tools/perf/util/namespaces.h @@ -49,6 +49,8 @@ void nsinfo__put(struct nsinfo *nsi); void nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc); void nsinfo__mountns_exit(struct nscookie *nc); +char *nsinfo__realpath(const char *path, struct nsinfo *nsi); + static inline void __nsinfo__zput(struct nsinfo **nsip) { if (nsip) { diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index a2670e9d652d..a80895a7e611 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -184,13 +184,19 @@ static struct map *kernel_get_module_map(const char *module) return NULL; } -struct map *get_target_map(const char *target, bool user) +struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user) { /* Init maps of given executable or kernel */ - if (user) - return dso__new_map(target); - else + if (user) { + struct map *map; + + map = dso__new_map(target); + if (map && map->dso) + map->dso->nsinfo = nsinfo__get(nsi); + return map; + } else { return kernel_get_module_map(target); + } } static int convert_exec_to_group(const char *exec, char **result) @@ -366,7 +372,8 @@ found: static int find_alternative_probe_point(struct debuginfo *dinfo, struct perf_probe_point *pp, struct perf_probe_point *result, - const char *target, bool uprobes) + const char *target, struct nsinfo *nsi, + bool uprobes) { struct map *map = NULL; struct symbol *sym; @@ -377,7 +384,7 @@ static int find_alternative_probe_point(struct debuginfo *dinfo, if (!pp->function || pp->file) return -ENOTSUP; - map = get_target_map(target, uprobes); + map = get_target_map(target, nsi, uprobes); if (!map) return -EINVAL; @@ -421,8 +428,8 @@ static int get_alternative_probe_event(struct debuginfo *dinfo, memcpy(tmp, &pev->point, sizeof(*tmp)); memset(&pev->point, 0, sizeof(pev->point)); - ret = find_alternative_probe_point(dinfo, tmp, &pev->point, - pev->target, pev->uprobes); + ret = find_alternative_probe_point(dinfo, tmp, &pev->point, pev->target, + pev->nsi, pev->uprobes); if (ret < 0) memcpy(&pev->point, tmp, sizeof(*tmp)); @@ -444,7 +451,7 @@ static int get_alternative_line_range(struct debuginfo *dinfo, if (lr->end != INT_MAX) len = lr->end - lr->start; ret = find_alternative_probe_point(dinfo, &pp, &result, - target, user); + target, NULL, user); if (!ret) { lr->function = result.function; lr->file = result.file; @@ -457,12 +464,14 @@ static int get_alternative_line_range(struct debuginfo *dinfo, } /* Open new debuginfo of given module */ -static struct debuginfo *open_debuginfo(const char *module, bool silent) +static struct debuginfo *open_debuginfo(const char *module, struct nsinfo *nsi, + bool silent) { const char *path = module; char reason[STRERR_BUFSIZE]; struct debuginfo *ret = NULL; struct dso *dso = NULL; + struct nscookie nsc; int err; if (!module || !strchr(module, '/')) { @@ -480,6 +489,7 @@ static struct debuginfo *open_debuginfo(const char *module, bool silent) } path = dso->long_name; } + nsinfo__mountns_enter(nsi, &nsc); ret = debuginfo__new(path); if (!ret && !silent) { pr_warning("The %s file has no debug information.\n", path); @@ -489,6 +499,7 @@ static struct debuginfo *open_debuginfo(const char *module, bool silent) pr_warning("Rebuild with -g, "); pr_warning("or install an appropriate debuginfo package.\n"); } + nsinfo__mountns_exit(&nsc); return ret; } @@ -516,7 +527,7 @@ static struct debuginfo *debuginfo_cache__open(const char *module, bool silent) goto out; } - debuginfo_cache = open_debuginfo(module, silent); + debuginfo_cache = open_debuginfo(module, NULL, silent); if (!debuginfo_cache) zfree(&debuginfo_cache_path); out: @@ -531,14 +542,18 @@ static void debuginfo_cache__exit(void) } -static int get_text_start_address(const char *exec, unsigned long *address) +static int get_text_start_address(const char *exec, unsigned long *address, + struct nsinfo *nsi) { Elf *elf; GElf_Ehdr ehdr; GElf_Shdr shdr; int fd, ret = -ENOENT; + struct nscookie nsc; + nsinfo__mountns_enter(nsi, &nsc); fd = open(exec, O_RDONLY); + nsinfo__mountns_exit(&nsc); if (fd < 0) return -errno; @@ -582,7 +597,7 @@ static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp, ret = -EINVAL; goto error; } - ret = get_text_start_address(tp->module, &stext); + ret = get_text_start_address(tp->module, &stext, NULL); if (ret < 0) goto error; addr += stext; @@ -659,7 +674,7 @@ post_process_offline_probe_trace_events(struct probe_trace_event *tevs, /* Prepare a map for offline binary */ map = dso__new_map(pathname); - if (!map || get_text_start_address(pathname, &stext) < 0) { + if (!map || get_text_start_address(pathname, &stext, NULL) < 0) { pr_warning("Failed to get ELF symbols for %s\n", pathname); return -EINVAL; } @@ -676,7 +691,8 @@ post_process_offline_probe_trace_events(struct probe_trace_event *tevs, } static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs, - int ntevs, const char *exec) + int ntevs, const char *exec, + struct nsinfo *nsi) { int i, ret = 0; unsigned long stext = 0; @@ -684,7 +700,7 @@ static int add_exec_to_probe_trace_events(struct probe_trace_event *tevs, if (!exec) return 0; - ret = get_text_start_address(exec, &stext); + ret = get_text_start_address(exec, &stext, nsi); if (ret < 0) return ret; @@ -715,7 +731,7 @@ post_process_module_probe_trace_events(struct probe_trace_event *tevs, if (!module) return 0; - map = get_target_map(module, false); + map = get_target_map(module, NULL, false); if (!map || debuginfo__get_text_offset(dinfo, &text_offs, true) < 0) { pr_warning("Failed to get ELF symbols for %s\n", module); return -EINVAL; @@ -802,7 +818,8 @@ static int post_process_probe_trace_events(struct perf_probe_event *pev, int ret; if (uprobe) - ret = add_exec_to_probe_trace_events(tevs, ntevs, module); + ret = add_exec_to_probe_trace_events(tevs, ntevs, module, + pev->nsi); else if (module) /* Currently ref_reloc_sym based probe is not for drivers */ ret = post_process_module_probe_trace_events(tevs, ntevs, @@ -825,7 +842,7 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev, struct debuginfo *dinfo; int ntevs, ret = 0; - dinfo = open_debuginfo(pev->target, !need_dwarf); + dinfo = open_debuginfo(pev->target, pev->nsi, !need_dwarf); if (!dinfo) { if (need_dwarf) return -ENOENT; @@ -945,7 +962,7 @@ static int __show_line_range(struct line_range *lr, const char *module, char sbuf[STRERR_BUFSIZE]; /* Search a line range */ - dinfo = open_debuginfo(module, false); + dinfo = open_debuginfo(module, NULL, false); if (!dinfo) return -ENOENT; @@ -1021,14 +1038,18 @@ end: return ret; } -int show_line_range(struct line_range *lr, const char *module, bool user) +int show_line_range(struct line_range *lr, const char *module, + struct nsinfo *nsi, bool user) { int ret; + struct nscookie nsc; ret = init_probe_symbol_maps(user); if (ret < 0) return ret; + nsinfo__mountns_enter(nsi, &nsc); ret = __show_line_range(lr, module, user); + nsinfo__mountns_exit(&nsc); exit_probe_symbol_maps(); return ret; @@ -1111,7 +1132,7 @@ int show_available_vars(struct perf_probe_event *pevs, int npevs, if (ret < 0) return ret; - dinfo = open_debuginfo(pevs->target, false); + dinfo = open_debuginfo(pevs->target, pevs->nsi, false); if (!dinfo) { ret = -ENOENT; goto out; @@ -1155,6 +1176,7 @@ static int try_to_find_probe_trace_events(struct perf_probe_event *pev, int show_line_range(struct line_range *lr __maybe_unused, const char *module __maybe_unused, + struct nsinfo *nsi __maybe_unused, bool user __maybe_unused) { pr_warning("Debuginfo-analysis is not supported.\n"); @@ -2703,6 +2725,7 @@ static int __add_probe_trace_events(struct perf_probe_event *pev, struct probe_trace_event *tev = NULL; struct probe_cache *cache = NULL; struct strlist *namelist[2] = {NULL, NULL}; + struct nscookie nsc; up = pev->uprobes ? 1 : 0; fd[up] = __open_probe_file_and_namelist(up, &namelist[up]); @@ -2729,7 +2752,9 @@ static int __add_probe_trace_events(struct perf_probe_event *pev, if (ret < 0) break; + nsinfo__mountns_enter(pev->nsi, &nsc); ret = probe_file__add_event(fd[up], tev); + nsinfo__mountns_exit(&nsc); if (ret < 0) break; @@ -2805,7 +2830,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, int ret, i, j, skipped = 0; char *mod_name; - map = get_target_map(pev->target, pev->uprobes); + map = get_target_map(pev->target, pev->nsi, pev->uprobes); if (!map) { ret = -EINVAL; goto out; @@ -3345,13 +3370,16 @@ int apply_perf_probe_events(struct perf_probe_event *pevs, int npevs) void cleanup_perf_probe_events(struct perf_probe_event *pevs, int npevs) { int i, j; + struct perf_probe_event *pev; /* Loop 3: cleanup and free trace events */ for (i = 0; i < npevs; i++) { + pev = &pevs[i]; for (j = 0; j < pevs[i].ntevs; j++) clear_probe_trace_event(&pevs[i].tevs[j]); zfree(&pevs[i].tevs); pevs[i].ntevs = 0; + nsinfo__zput(pev->nsi); clear_perf_probe_event(&pevs[i]); } } @@ -3409,8 +3437,8 @@ out: return ret; } -int show_available_funcs(const char *target, struct strfilter *_filter, - bool user) +int show_available_funcs(const char *target, struct nsinfo *nsi, + struct strfilter *_filter, bool user) { struct rb_node *nd; struct map *map; @@ -3421,7 +3449,7 @@ int show_available_funcs(const char *target, struct strfilter *_filter, return ret; /* Get a symbol map */ - map = get_target_map(target, user); + map = get_target_map(target, nsi, user); if (!map) { pr_err("Failed to get a map for %s\n", (target) ? : "kernel"); return -EINVAL; diff --git a/tools/perf/util/probe-event.h b/tools/perf/util/probe-event.h index 5812947418dd..078681d12168 100644 --- a/tools/perf/util/probe-event.h +++ b/tools/perf/util/probe-event.h @@ -4,6 +4,7 @@ #include <linux/compiler.h> #include <stdbool.h> #include "intlist.h" +#include "namespaces.h" /* Probe related configurations */ struct probe_conf { @@ -92,6 +93,7 @@ struct perf_probe_event { struct perf_probe_arg *args; /* Arguments */ struct probe_trace_event *tevs; int ntevs; + struct nsinfo *nsi; /* Target namespace */ }; /* Line range */ @@ -163,10 +165,12 @@ int show_perf_probe_event(const char *group, const char *event, struct perf_probe_event *pev, const char *module, bool use_stdout); int show_perf_probe_events(struct strfilter *filter); -int show_line_range(struct line_range *lr, const char *module, bool user); +int show_line_range(struct line_range *lr, const char *module, + struct nsinfo *nsi, bool user); int show_available_vars(struct perf_probe_event *pevs, int npevs, struct strfilter *filter); -int show_available_funcs(const char *module, struct strfilter *filter, bool user); +int show_available_funcs(const char *module, struct nsinfo *nsi, + struct strfilter *filter, bool user); void arch__fix_tev_from_maps(struct perf_probe_event *pev, struct probe_trace_event *tev, struct map *map, struct symbol *sym); @@ -180,7 +184,7 @@ int e_snprintf(char *str, size_t size, const char *format, ...) __printf(3, 4); int copy_to_probe_trace_arg(struct probe_trace_arg *tvar, struct perf_probe_arg *pvar); -struct map *get_target_map(const char *target, bool user); +struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user); void arch__post_process_probe_trace_events(struct perf_probe_event *pev, int ntevs); |