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 <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Brendan Gregg <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: David Ahern <[email protected]> Cc: He Kuang <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kaixu Xia <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Zefan Li <[email protected]> Cc: [email protected] Cc: Arnaldo Carvalho de Melo <[email protected]> Link: http://lkml.kernel.org/n/[email protected] --- 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 [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
