linux.git/tools/testing/selftests/resctrl/cat_test.c, branch v6.6-rc2

selftests/resctrl: Pass the real number of tests to show_cache_info()

2023-07-25T14:54:05+00:00

Results include warm-up test which is discarded before passing the sum
to show_cache_info(). show_cache_info() handles this by subtracting one
from the number of tests in divisor. It is a trappy construct to have
sum and number of tests parameters to disagree like this.

A more logical place for subtracting the skipped tests is where the sum
is calculated so move it there. Pass the correct number of tests to
show_cache_info() so it can be used directly as the divisor for
calculating the average.

Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Tested-by: Babu Moger 
Tested-by: Shaopeng Tan (Fujitsu) 
Signed-off-by: Shuah Khan

selftests/resctrl: Move CAT/CMT test global vars to function they are used in

2023-07-25T14:53:59+00:00

CAT and CMT tests have count_of_bits, long_mask, cbm_mask, and
cache_size global variables that can be moved into the sole using
function.

Make the global variables local variables of the relevant function to
scope them better.

While at it, move cache_size initialization into the declaration line.

Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Tested-by: Babu Moger 
Tested-by: Shaopeng Tan (Fujitsu) 
Signed-off-by: Shuah Khan

selftests/resctrl: Don't use variable argument list for ->setup()

2023-07-25T14:53:53+00:00

struct resctrl_val_param has ->setup() function that accepts variable
argument list. All test cases use only 1 argument as input and it's
the struct resctrl_val_param pointer.

Instead of variable argument list, directly pass struct
resctrl_val_param pointer as the only parameter to ->setup().

Co-developed-by: Fenghua Yu 
Signed-off-by: Fenghua Yu 
Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Tested-by: Babu Moger 
Tested-by: Shaopeng Tan (Fujitsu) 
Signed-off-by: Shuah Khan

selftests/resctrl: Remove mum_resctrlfs from struct resctrl_val_param

2023-07-25T14:53:06+00:00

Resctrl FS mount/umount are now cleanly paired leaving .mum_resctrlfs
in the struct resctrl_val_param unused.

Remove .mum_resctrlfs from struct resctrl_val_param.

Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Tested-by: Babu Moger 
Tested-by: Shaopeng Tan (Fujitsu) 
Signed-off-by: Shuah Khan

selftests/resctrl: Move resctrl FS mount/umount to higher level

2023-07-25T14:52:54+00:00

A few places currently lack umounting resctrl FS on error paths:
  - cmt_resctrl_val() has multiple error paths with direct return.
  - cat_perf_miss_val() has multiple error paths with direct return.
In addition, validate_resctrl_feature_request() is called by
run_mbm_test() and run_mba_test(). Neither MBA nor MBM test tries to
umount resctrl FS.

Each and every test does require resctrl FS to be present already for
feature check. Thus, it makes sense to just mount it on higher level in
resctrl_tests.c and properly pair it with umount.

Move resctrl FS (re)mount/unmount into each test function in
resctrl_tests.c. Make feature validation to simply check that resctrl
FS is mounted.

As there's the final umount in main() before this change, the selftest
should not leave resctrl FS behind after the tests even if one of the
forementioned paths is taken (thus, no fixes tag).

Signed-off-by: Ilpo Järvinen 
Tested-by: Babu Moger 
Tested-by: Shaopeng Tan (Fujitsu) 
Signed-off-by: Shuah Khan

selftests/resctrl: Commonize the signal handler register/unregister for all tests

2023-04-13T17:34:23+00:00

After creating a child process with fork() in CAT test, if a signal such
as SIGINT is received, the parent process will be terminated immediately,
and therefore the child process will not be killed and also resctrlfs is
not unmounted.

There is a signal handler registered in CMT/MBM/MBA tests, which kills
child process, unmount resctrlfs, cleanups result files, etc., if a
signal such as SIGINT is received.

Commonize the signal handler registered for CMT/MBM/MBA tests and
reuse it in CAT.

To reuse the signal handler to kill child process use global bm_pid
instead of local bm_pid.

Also, since the MBA/MBA/CMT/CAT are run in order, unregister the signal
handler at the end of each test so that the signal handler cannot be
inherited by other tests.

Reviewed-by: Ilpo Jarvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shaopeng Tan 
Signed-off-by: Shuah Khan

selftests/resctrl: Cleanup properly when an error occurs in CAT test

2023-04-13T17:34:17+00:00

After creating a child process with fork() in CAT test, if an error
occurs when parent process runs cat_val() or check_results(), the child
process will not be killed and also resctrlfs is not unmounted. Also if
an error occurs when child process runs cat_val() or check_results(),
the parent process will wait for the pipe message from the child process
which will never be sent by the child process and the parent process
cannot proceed to unmount resctrlfs.

Synchronize the exits between the parent and child. An error could
occur whether in parent process or child process. The parent process
always kills the child process and runs umount_resctrlfs(). The
child process always waits to be killed by the parent process.

Reviewed-by: Reinette Chatre 
Signed-off-by: Shaopeng Tan 
Signed-off-by: Shuah Khan

selftests/resctrl: Flush stdout file buffer before executing fork()

2023-04-13T17:34:12+00:00

When a process has buffered output, a child process created by fork()
will also copy buffered output. When using kselftest framework,
the output (resctrl test result message) will be printed multiple times.

Add fflush() to flush out the buffered output before executing fork().

Reviewed-by: Shuah Khan 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shaopeng Tan 
Signed-off-by: Shuah Khan

selftests/resctrl: Use remount_resctrlfs() consistently with boolean

2023-04-10T18:21:10+00:00

remount_resctrlfs() accepts a boolean value as an argument. Some tests
pass 0/1 and some tests pass true/false.

Make all the callers of remount_resctrlfs() use true/false so that the
parameter usage is consistent across tests.

Co-developed-by: Fenghua Yu 
Signed-off-by: Fenghua Yu 
Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan

selftests/resctrl: Allow ->setup() to return errors

2023-04-10T18:20:41+00:00

resctrl_val() assumes ->setup() always returns either 0 to continue
tests or < 0 in case of the normal termination of tests after x runs.
The latter overlaps with normal error returns.

Define END_OF_TESTS (=1) to differentiate the normal termination of
tests and return errors as negative values. Alter callers of ->setup()
to handle errors properly.

Fixes: 790bf585b0ee ("selftests/resctrl: Add Cache Allocation Technology (CAT) selftest")
Fixes: ecdbb911f22d ("selftests/resctrl: Add MBM test")
Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan