| Message ID | 1444826502-49291-21-git-send-email-wangnan0@huawei.com |
|---|---|
| State | New |
| Headers | show |
On 2015/10/14 20:41, Wang Nan wrote: > This patch appends new syntax to BPF object section name to support > probing at uprobe event. Now we can use BPF program like this: > > SEC( > "target=/lib64/libc.so.6\n" > "libcwrite=__write" > ) > int libcwrite(void *ctx) > { > return 1; > } > > Where, in section name of a program, before the main config string, > we can use 'key=value' style options. Now the only option key "target" > is for uprobe probing. > > Signed-off-by: Wang Nan <wangnan0@huawei.com> > Cc: Alexei Starovoitov <ast@plumgrid.com> > Cc: Brendan Gregg <brendan.d.gregg@gmail.com> > Cc: Daniel Borkmann <daniel@iogearbox.net> > Cc: David Ahern <dsahern@gmail.com> > Cc: He Kuang <hekuang@huawei.com> > Cc: Jiri Olsa <jolsa@kernel.org> > Cc: Kaixu Xia <xiakaixu@huawei.com> > Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> > Cc: Namhyung Kim <namhyung@kernel.org> > Cc: Paul Mackerras <paulus@samba.org> > Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> > Cc: Zefan Li <lizefan@huawei.com> > Cc: pi3orama@163.com > Cc: Arnaldo Carvalho de Melo <acme@redhat.com> > Link: http://lkml.kernel.org/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@git.kernel.org > --- > tools/perf/util/bpf-loader.c | 86 ++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 80 insertions(+), 6 deletions(-) > > diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c > index af549ea..73ff9a9 100644 > --- a/tools/perf/util/bpf-loader.c > +++ b/tools/perf/util/bpf-loader.c > @@ -111,6 +111,84 @@ bpf_prog_priv__clear(struct bpf_program *prog __maybe_unused, > } > > static int > +do_config(const char *key, const char *value, > + struct perf_probe_event *pev) > +{ > + pr_debug("config bpf program: %s=%s\n", key, value); > + if (strcmp(key, "target") == 0) { > + pev->uprobes = true; > + pev->target = strdup(value); > + return 0; > + } > + > + pr_warning("BPF: WARNING: invalid config option in object: %s=%s\n", > + key, value); > + pr_warning("\tHint: Currently only valid option is 'target=<file>'\n"); > + return 0; > +} > This part is very easy to be extended to support probing at modules. I'd like to change "target" to "exec" to make it unify with perf probe, then add another patch to support module probing in next pull request. Thank you. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/tools/perf/util/bpf-loader.c b/tools/perf/util/bpf-loader.c index af549ea..73ff9a9 100644 --- a/tools/perf/util/bpf-loader.c +++ b/tools/perf/util/bpf-loader.c @@ -111,6 +111,84 @@ bpf_prog_priv__clear(struct bpf_program *prog __maybe_unused, } static int +do_config(const char *key, const char *value, + struct perf_probe_event *pev) +{ + pr_debug("config bpf program: %s=%s\n", key, value); + if (strcmp(key, "target") == 0) { + pev->uprobes = true; + pev->target = strdup(value); + return 0; + } + + pr_warning("BPF: WARNING: invalid config option in object: %s=%s\n", + key, value); + pr_warning("\tHint: Currently only valid option is 'target=<file>'\n"); + return 0; +} + +static const char * +parse_config_kvpair(const char *config_str, struct perf_probe_event *pev) +{ + char *text = strdup(config_str); + char *sep, *line; + const char *main_str = NULL; + int err = 0; + + if (!text) { + pr_debug("No enough memory: dup config_str failed\n"); + return NULL; + } + + line = text; + while ((sep = strchr(line, '\n'))) { + char *equ; + + *sep = '\0'; + equ = strchr(line, '='); + if (!equ) { + pr_warning("WARNING: invalid config in BPF object: %s\n", + line); + pr_warning("\tShould be 'key=value'.\n"); + goto nextline; + } + *equ = '\0'; + + err = do_config(line, equ + 1, pev); + if (err) + break; +nextline: + line = sep + 1; + } + + if (!err) + main_str = config_str + (line - text); + free(text); + + return main_str; +} + +static int +parse_config(const char *config_str, struct perf_probe_event *pev) +{ + const char *main_str; + int err; + + main_str = parse_config_kvpair(config_str, pev); + if (!main_str) + return -EINVAL; + + err = parse_perf_probe_command(main_str, pev); + if (err < 0) { + pr_debug("bpf: '%s' is not a valid config string\n", + config_str); + /* parse failed, don't need clear pev. */ + return -EINVAL; + } + return 0; +} + +static int config_bpf_program(struct bpf_program *prog) { struct perf_probe_event *pev = NULL; @@ -132,13 +210,9 @@ config_bpf_program(struct bpf_program *prog) pev = &priv->pev; pr_debug("bpf: config program '%s'\n", config_str); - err = parse_perf_probe_command(config_str, pev); - if (err < 0) { - pr_debug("bpf: '%s' is not a valid config string\n", - config_str); - err = -EINVAL; + err = parse_config(config_str, pev); + if (err) goto errout; - } if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) { pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
This patch appends new syntax to BPF object section name to support probing at uprobe event. Now we can use BPF program like this: SEC( "target=/lib64/libc.so.6\n" "libcwrite=__write" ) int libcwrite(void *ctx) { return 1; } Where, in section name of a program, before the main config string, we can use 'key=value' style options. Now the only option key "target" is for uprobe probing. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: David Ahern <dsahern@gmail.com> Cc: He Kuang <hekuang@huawei.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kaixu Xia <xiakaixu@huawei.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Link: http://lkml.kernel.org/n/ebpf-6yw9eg0ej3l4jnqhinngkw86@git.kernel.org --- tools/perf/util/bpf-loader.c | 86 ++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 80 insertions(+), 6 deletions(-)