[0/3] tracing: synth_event_trace fixes
mbox

Message ID cover.1581630377.git.zanussi@kernel.org
State New
Headers show

Pull-request

git://git.kernel.org/pub/scm/linux/kernel/git/zanussi/linux-trace.git ftrace/synth-event-gen-fixes2-v1

Message

Tom Zanussi Feb. 13, 2020, 10:16 p.m. UTC
Hi Steve,

Sorry, it took me some time to get a 32-bit x86 system up and running
here in order to build and test things on i386.  These patches pass
both selftests and the synth_event_gen_test testing, although the bug
where (null) prints after every integer field in the trace output is
still there and is there even before these or yesterday's patches - I
have a suspicion it's been there for awhile but nobody looked at
synthetic event trace output on i386.  In any case, I'm going to
continue looking into that - it's a weird situation where nothing gets
put in the final %s in the format string on i386 so shows as (null),
even though it looks like it's there.  Anyway..

Here are 3 bugfix patches, the first of which fixes the bug seen by
the test robot, and the other two are patches that fix a couple things
I noticed when doing the first patch.

The previous patch I sent, changing u64 to long for the test robot bug
did fix that problem too, but on i386 systems that would reduce every
field to 32 bits, which isn't what we want either.  The new patch
doesn't change the code in synth_event_trace() - it still uses u64
just like synth_event_trace_array() which takes an array of u64.
Without any further information such as a format string, I don't know
of a better way to deal with the varargs version, other than require
it get passed what it expects, u64 params.

The second patch adds the same endianness fix as for
trace_event_raw_event_synth(), and the last one just adds back a
missing check fot synth_event_trace() and synth_event_trace_array().

Thanks,

Tom

The following changes since commit 359c92c02bfae1a6f1e8e37c298e518fd256642c:

  Merge tag 'dax-fixes-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm (2020-02-11 16:52:08 -0800)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/zanussi/linux-trace.git ftrace/synth-event-gen-fixes2-v1

Tom Zanussi (3):
  tracing: Make sure synth_event_trace() example always uses u64
  tracing: Make synth_event trace functions endian-correct
  tracing: Check that number of vals matches number of synth  event
    fields

 kernel/trace/synth_event_gen_test.c | 34 +++++++++----------
 kernel/trace/trace_events_hist.c    | 68 ++++++++++++++++++++++++++++++++++---
 2 files changed, 81 insertions(+), 21 deletions(-)

Comments

Tom Zanussi Feb. 13, 2020, 11:36 p.m. UTC | #1
Hi Steve,

I apparently tested the wrong patches, and while I think patch 1 and 3
are ok, I'm seeing a problem with patch 2 (then endian changes).  Will
send a v2 as soon as I can.

Tom

On Thu, 2020-02-13 at 16:16 -0600, Tom Zanussi wrote:
> Hi Steve,
> 
> Sorry, it took me some time to get a 32-bit x86 system up and running
> here in order to build and test things on i386.  These patches pass
> both selftests and the synth_event_gen_test testing, although the bug
> where (null) prints after every integer field in the trace output is
> still there and is there even before these or yesterday's patches - I
> have a suspicion it's been there for awhile but nobody looked at
> synthetic event trace output on i386.  In any case, I'm going to
> continue looking into that - it's a weird situation where nothing
> gets
> put in the final %s in the format string on i386 so shows as (null),
> even though it looks like it's there.  Anyway..
> 
> Here are 3 bugfix patches, the first of which fixes the bug seen by
> the test robot, and the other two are patches that fix a couple
> things
> I noticed when doing the first patch.
> 
> The previous patch I sent, changing u64 to long for the test robot
> bug
> did fix that problem too, but on i386 systems that would reduce every
> field to 32 bits, which isn't what we want either.  The new patch
> doesn't change the code in synth_event_trace() - it still uses u64
> just like synth_event_trace_array() which takes an array of u64.
> Without any further information such as a format string, I don't know
> of a better way to deal with the varargs version, other than require
> it get passed what it expects, u64 params.
> 
> The second patch adds the same endianness fix as for
> trace_event_raw_event_synth(), and the last one just adds back a
> missing check fot synth_event_trace() and synth_event_trace_array().
> 
> Thanks,
> 
> Tom
> 
> The following changes since commit
> 359c92c02bfae1a6f1e8e37c298e518fd256642c:
> 
>   Merge tag 'dax-fixes-5.6-rc1' of
> git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm (2020-02-
> 11 16:52:08 -0800)
> 
> are available in the git repository at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/zanussi/linux-
> trace.git ftrace/synth-event-gen-fixes2-v1
> 
> Tom Zanussi (3):
>   tracing: Make sure synth_event_trace() example always uses u64
>   tracing: Make synth_event trace functions endian-correct
>   tracing: Check that number of vals matches number of synth  event
>     fields
> 
>  kernel/trace/synth_event_gen_test.c | 34 +++++++++----------
>  kernel/trace/trace_events_hist.c    | 68
> ++++++++++++++++++++++++++++++++++---
>  2 files changed, 81 insertions(+), 21 deletions(-)
>
Steven Rostedt Feb. 13, 2020, 11:54 p.m. UTC | #2
On Thu, 13 Feb 2020 17:36:14 -0600
Tom Zanussi <tzanussi@gmail.com> wrote:

> Hi Steve,
> 
> I apparently tested the wrong patches, and while I think patch 1 and 3
> are ok, I'm seeing a problem with patch 2 (then endian changes).  Will
> send a v2 as soon as I can.
> 

Due to other priorities, I haven't had a chance to look at theses yet.
So no hurry.

-- Steve