| Message ID | 20200115180645.53331-1-john.koepi@gmail.com (mailing list archive) |
|---|---|
| State | Handled Elsewhere |
| Headers | show |
| Series | [bpf] traceevent: ignore __attribute__ in fields format | expand |
I am not sure this is the right mailing list (I was not sure about @netdev). If it is not - I am sorry, I can resend it. The test for this change is at https://github.com/sitano/traceevent_attribute. On Wed, Jan 15, 2020 at 8:06 PM Ivan Prisyazhnyy <john.koepi@gmail.com> wrote: > > To support kernel (e.g. Arch linux) tracing that > have events fields with C attributes (__attribute__((xxx))), > traceevent must ignore __attribute__ parts when > parsing fields types. > > An example from Arch linux kernel 4.2: > > $ cat /sys/kernel/.../sys_enter_io_submit/format > ... > field:struct iocb __attribute__((user)) * ... > ^^^ > > This fix adds support for fields types C attributes > parsing to event_read_fields function. When it sees > __attribute__ ((attribute-list)) expression it skips > it. > > Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=205857 > Base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/ > Signed-off-by: Ivan Prisyazhnyy <john.koepi@gmail.com> > --- > tools/lib/traceevent/event-parse.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c > index beaa8b8c08ff..fbc1ea536742 100644 > --- a/tools/lib/traceevent/event-parse.c > +++ b/tools/lib/traceevent/event-parse.c > @@ -1486,6 +1486,28 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field ** > (event->flags & TEP_EVENT_FL_ISFTRACE && > type == TEP_EVENT_OP && strcmp(token, ".") == 0)) { > > + /* ignore C attributes: __attribute__((expr)) */ > + if (strcmp(token, "__attribute__") == 0) { > + free(token); > + for (int i = 0; i < 2; i++) { > + if (read_expected_item(TEP_EVENT_DELIM, "(") < 0) { > + goto fail_expect; > + } > + } > + for (int brackets = 2; brackets > 0;) { > + if (read_token(&token) == TEP_EVENT_NONE) { > + do_warning_event(event, "%s: __attribute__ not full", __func__); > + goto fail_expect; > + } > + if (strcmp(token, "(") == 0) > + brackets++; > + else if (strcmp(token, ")") == 0) > + brackets--; > + free(token); > + } > + continue; > + } > + > if (strcmp(token, "*") == 0) > field->flags |= TEP_FIELD_IS_POINTER; > > -- > 2.24.1 >
On Wed, 15 Jan 2020 20:47:47 +0200 John Koepi <john.koepi@gmail.com> wrote: > I am not sure this is the right mailing list (I was not sure about > @netdev). If it is not - I am sorry, I can resend it. The test for > this change is at https://github.com/sitano/traceevent_attribute. > It's fine to send it here. It's in my queue to look at. Thanks! -- Steve
diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c index beaa8b8c08ff..fbc1ea536742 100644 --- a/tools/lib/traceevent/event-parse.c +++ b/tools/lib/traceevent/event-parse.c @@ -1486,6 +1486,28 @@ static int event_read_fields(struct tep_event *event, struct tep_format_field ** (event->flags & TEP_EVENT_FL_ISFTRACE && type == TEP_EVENT_OP && strcmp(token, ".") == 0)) { + /* ignore C attributes: __attribute__((expr)) */ + if (strcmp(token, "__attribute__") == 0) { + free(token); + for (int i = 0; i < 2; i++) { + if (read_expected_item(TEP_EVENT_DELIM, "(") < 0) { + goto fail_expect; + } + } + for (int brackets = 2; brackets > 0;) { + if (read_token(&token) == TEP_EVENT_NONE) { + do_warning_event(event, "%s: __attribute__ not full", __func__); + goto fail_expect; + } + if (strcmp(token, "(") == 0) + brackets++; + else if (strcmp(token, ")") == 0) + brackets--; + free(token); + } + continue; + } + if (strcmp(token, "*") == 0) field->flags |= TEP_FIELD_IS_POINTER;
To support kernel (e.g. Arch linux) tracing that have events fields with C attributes (__attribute__((xxx))), traceevent must ignore __attribute__ parts when parsing fields types. An example from Arch linux kernel 4.2: $ cat /sys/kernel/.../sys_enter_io_submit/format ... field:struct iocb __attribute__((user)) * ... ^^^ This fix adds support for fields types C attributes parsing to event_read_fields function. When it sees __attribute__ ((attribute-list)) expression it skips it. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=205857 Base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/ Signed-off-by: Ivan Prisyazhnyy <john.koepi@gmail.com> --- tools/lib/traceevent/event-parse.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)