Hello Aditya,

On Wed, Jun 21, 2023 at 11:43 AM Aditya Gupta [off-list ref] wrote:

Hello Namhyung,

On 21/06/23 20:53, Namhyung Kim wrote:

quoted

Hello Aditya,

On Wed, Jun 21, 2023 at 3:05 AM Aditya Gupta [off-list ref] wrote:

quoted

Hello Namhyung,

On 21/06/23 06:18, Namhyung Kim wrote:

quoted

...

$ sudo ./perf test -v task
114: perf script task-analyzer tests                                 :

--- start ---

test child forked, pid 1771042
Please specify a valid report script(see 'perf script -l' for listing)
FAIL: "invocation of perf command failed" Error message: ""
FAIL: "test_basic" Error message: "Failed to find required string:'Comm'."
Please specify a valid report script(see 'perf script -l' for listing)
FAIL: "invocation of perf command failed" Error message: ""
FAIL: "test_ns_rename" Error message: "Failed to find required string:'Comm'."
...
test child finished with -1
---- end ----
perf script task-analyzer tests: FAILED!

Can you please check if your environment has libtraceevent devel
libraries (or did you compile with `make NO_LIBTRACEEVENT=1`) ? When
libtraceevent support is not there, perf record fails and so perf.data
doesn't contain the strings it's searching for and hence those errors

The error you mentioned has been mentioned and fixed in patch 17/17 of
this series.

Thanks for your reply but It has libtraceevent.  Also, shouldn't it
skip if it's not?

Thanks,
Namhyung

The skipping is handled in the 17th patch in this series, and
considering that patch has also been applied, it will skip the tests if
perf wasn't built with proper libtraceevent support.

Right, I tested it with the whole series applied.
It skipped to run when I disable libtraceevent build.

Back to the error, Sorry but I tested again on my system and am unable to reproduce the issue you are seeing when built with libtraceevent support.

This is what I did:

0. git clone --depth=1 https://github.com/torvalds/linux
0. cd linux/tools/perf
0. git am patch_15/17.patch

quoted

I applied ONLY this patch (15/17) of this series, to a fresh linux tree

1. dnf install libtraceevent-devel
2. make clean && make
3. sudo ./perf test -v "perf script task-analyzer tests"       # Working fine, tests passed

4. dnf remove libtraceevent-devel
5. make clean && make                                          # There will also be a warning during build: "libtraceevent is missing limiting functionality"
6. sudo ./perf test -v "perf script task-analyzer tests"       # Fails with the error you posted, which was the case till now, it's skipped when the 17th patch is also applied and perf built without libtraceevent support

The error in the second case (without proper libtraceevent support) is expected, as it was the case till now, that is fixed by the 17th patch, try applying that also and build perf with `make NO_LIBTRACEEVENT=1`, it will skip then.

Can you guide me with the steps to reproduce the error ?

You can try the perf-tools-next branch in the perf/perft-tools-next.git repo.

  git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git

  $ make clean all
  $ sudo ./perf test -v task

Sidenote: Just in case, please ensure you are running the perf as root here as `perf record -e sched:sched_switch -a -- sleep 1` requires root, which has been used in `prepare_perf_data`

Sure, I ran the perf test as root.

Thanks,
Namhyung