[PATCH 09/77] perf trace: Introduce augmented_filename_syscall_enter() declarator

From: Arnaldo Carvalho de Melo
Date: Wed Sep 05 2018 - 18:05:21 EST


From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

Helping with tons of boilerplate for syscalls that only want to augment
a filename. Now supporting one such syscall is just a matter of
declaring its arguments struct + using:

augmented_filename_syscall_enter(openat);

Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-ls7ojdseu8fxw7fvj77ejpao@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/examples/bpf/augmented_syscalls.c | 78 ++++++++--------------------
1 file changed, 23 insertions(+), 55 deletions(-)

diff --git a/tools/perf/examples/bpf/augmented_syscalls.c b/tools/perf/examples/bpf/augmented_syscalls.c
index 6ec327850a15..e8486e8597de 100644
--- a/tools/perf/examples/bpf/augmented_syscalls.c
+++ b/tools/perf/examples/bpf/augmented_syscalls.c
@@ -33,6 +33,25 @@ struct augmented_filename {
char value[256];
};

+#define augmented_filename_syscall_enter(syscall) \
+struct augmented_enter_##syscall##_args { \
+ struct syscall_enter_##syscall##_args args; \
+ struct augmented_filename filename; \
+}; \
+int syscall_enter(syscall)(struct syscall_enter_##syscall##_args *args) \
+{ \
+ struct augmented_enter_##syscall##_args augmented_args = { .filename.reserved = 0, }; \
+ probe_read(&augmented_args.args, sizeof(augmented_args.args), args); \
+ augmented_args.filename.size = probe_read_str(&augmented_args.filename.value, \
+ sizeof(augmented_args.filename.value), \
+ args->filename_ptr); \
+ perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU, \
+ &augmented_args, \
+ (sizeof(augmented_args) - sizeof(augmented_args.filename.value) + \
+ augmented_args.filename.size)); \
+ return 0; \
+}
+
struct syscall_enter_openat_args {
unsigned long long common_tp_fields;
long syscall_nr;
@@ -42,24 +61,7 @@ struct syscall_enter_openat_args {
long mode;
};

-struct augmented_enter_openat_args {
- struct syscall_enter_openat_args args;
- struct augmented_filename filename;
-};
-
-int syscall_enter(openat)(struct syscall_enter_openat_args *args)
-{
- struct augmented_enter_openat_args augmented_args = { .filename.reserved = 0, };
-
- probe_read(&augmented_args.args, sizeof(augmented_args.args), args);
- augmented_args.filename.size = probe_read_str(&augmented_args.filename.value,
- sizeof(augmented_args.filename.value),
- args->filename_ptr);
- perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU,
- &augmented_args,
- sizeof(augmented_args) - sizeof(augmented_args.filename.value) + augmented_args.filename.size);
- return 0;
-}
+augmented_filename_syscall_enter(openat);

struct syscall_enter_open_args {
unsigned long long common_tp_fields;
@@ -69,50 +71,16 @@ struct syscall_enter_open_args {
long mode;
};

-struct augmented_enter_open_args {
- struct syscall_enter_open_args args;
- struct augmented_filename filename;
-};
-
-int syscall_enter(open)(struct syscall_enter_open_args *args)
-{
- struct augmented_enter_open_args augmented_args = { .filename.reserved = 0, };
-
- probe_read(&augmented_args.args, sizeof(augmented_args.args), args);
- augmented_args.filename.size = probe_read_str(&augmented_args.filename.value,
- sizeof(augmented_args.filename.value),
- args->filename_ptr);
- perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU,
- &augmented_args,
- sizeof(augmented_args) - sizeof(augmented_args.filename.value) + augmented_args.filename.size);
- return 0;
-}
+augmented_filename_syscall_enter(open);

struct syscall_enter_inotify_add_watch_args {
unsigned long long common_tp_fields;
long syscall_nr;
long fd;
- char *pathname_ptr;
+ char *filename_ptr;
long mask;
};

-struct augmented_enter_inotify_add_watch_args {
- struct syscall_enter_inotify_add_watch_args args;
- struct augmented_filename pathname;
-};
-
-int syscall_enter(inotify_add_watch)(struct syscall_enter_inotify_add_watch_args *args)
-{
- struct augmented_enter_inotify_add_watch_args augmented_args = { .pathname.reserved = 0, };
-
- probe_read(&augmented_args.args, sizeof(augmented_args.args), args);
- augmented_args.pathname.size = probe_read_str(&augmented_args.pathname.value,
- sizeof(augmented_args.pathname.value),
- args->pathname_ptr);
- perf_event_output(args, &__augmented_syscalls__, BPF_F_CURRENT_CPU,
- &augmented_args,
- sizeof(augmented_args) - sizeof(augmented_args.pathname.value) + augmented_args.pathname.size);
- return 0;
-}
+augmented_filename_syscall_enter(inotify_add_watch);

license(GPL);
--
2.14.4