From: Arnaldo Carvalho de Melo <a...@redhat.com> Just to test filtering a bunch of pids, now its time to go and get that hooked up in 'perf trace', right after we load the bpf program, if we find a "pids_filtered" map defined, we'll populate it with the filtered pids.
Cc: Adrian Hunter <adrian.hun...@intel.com> Cc: David Ahern <dsah...@gmail.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Wang Nan <wangn...@huawei.com> Link: https://lkml.kernel.org/n/tip-1i9s27wqqdhafk3fappow...@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/examples/bpf/augmented_raw_syscalls.c | 34 ++++++++++++++++++++++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/tools/perf/examples/bpf/augmented_raw_syscalls.c b/tools/perf/examples/bpf/augmented_raw_syscalls.c index 7d729319618c..5fed1eff889d 100644 --- a/tools/perf/examples/bpf/augmented_raw_syscalls.c +++ b/tools/perf/examples/bpf/augmented_raw_syscalls.c @@ -16,6 +16,7 @@ #include <stdio.h> #include <unistd.h> +#include <pid_filter.h> /* bpf-output associated map */ struct bpf_map SEC("maps") __augmented_syscalls__ = { @@ -48,6 +49,29 @@ struct augmented_filename { #define SYS_POLL 7 #define SYS_OPENAT 257 +pid_filter(pids_filtered); + +static void pid_filter__init(void) +{ + /* + * Filter a bunch of pids: gnome-shell, kvm, firefox threads, + * avahi-daemon, etc, just for testing as we go along. + * + * These will come from 'perf trace --filter-pids' in a explicit way + * and also it will filter out itself, to avoid the feedback loop: + * syscalls 'perf trace' does gets caught, reported, causing new + * syscalls to get emitted, rinse repeat forever. + */ + if (pid_filter__add(&pids_filtered, 2971)) + return; /* pid_filter__init() was already called, bail out */ + pid_filter__add(&pids_filtered, 20016); + pid_filter__add(&pids_filtered, 12018); + pid_filter__add(&pids_filtered, 2310); + pid_filter__add(&pids_filtered, 3759); + pid_filter__add(&pids_filtered, 25978); + pid_filter__add(&pids_filtered, 883); +} + SEC("raw_syscalls:sys_enter") int sys_enter(struct syscall_enter_args *args) { @@ -57,8 +81,14 @@ int sys_enter(struct syscall_enter_args *args) } augmented_args; unsigned int len = sizeof(augmented_args); const void *filename_arg = NULL; + /* + * We still don't have a "main()" called first and only once + * call it always, it will exit as soon as it realizes the + * first hard coded filtered pid was already added. + */ + pid_filter__init(); - if (getpid() == 2971) + if (pid_filter__has(&pids_filtered, getpid())) return 0; probe_read(&augmented_args.args, sizeof(augmented_args.args), args); @@ -132,7 +162,7 @@ int sys_enter(struct syscall_enter_args *args) SEC("raw_syscalls:sys_exit") int sys_exit(struct syscall_exit_args *args) { - return getpid() != 2971; + return !pid_filter__has(&pids_filtered, getpid()); } license(GPL); -- 2.14.5
