History log of /linux-master/tools/testing/selftests/resctrl/cat_test.c
Revision Date Author Comments
# ae638551 16-Feb-2024 Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com>

selftests/resctrl: Add non-contiguous CBMs CAT test

Add tests for both L2 and L3 CAT to verify the return values
generated by writing non-contiguous CBMs don't contradict the
reported non-contiguous support information.

Use a logical XOR to confirm return value of write_schemata() and
non-contiguous CBMs support information match.

Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 5339792b 16-Feb-2024 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Add test groups and name L3 CAT test L3_CAT

To select test to run -t parameter can be used. However, -t cat
currently maps to L3 CAT test which will be confusing after more CAT
related tests will be added.

Allow selecting tests as groups and call L3 CAT test "L3_CAT", "CAT"
group will enable all CAT related tests.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# ca160887 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Pass write_schemata() resource instead of test name

write_schemata() takes the test name as an argument and determines the
relevant resource based on the test name. Such mapping from name to
resource does not really belong to resctrlfs.c that should provide
only generic, test-independent functions.

Pass the resource stored in the test information structure to
write_schemata() instead of the test name. The new API is also more
flexible as it enables to use write_schemata() for more than one
resource within a test.

While touching the sprintf(), move the unnecessary %c that is always
'=' directly into the format string.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# c603ff5b 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Introduce generalized test framework

Each test currently has a "run test" function in per test file and
another resctrl_tests.c. The functions in resctrl_tests.c are almost
identical.

Generalize the one in resctrl_tests.c such that it can be shared
between all of the tests. It makes adding new tests easier and removes
the per test if () forests.

Also add comment to CPU vendor IDs that they must be defined as bits
for a bitmask.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 15f29882 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Create struct for input parameters

resctrl_tests reads a set of parameters and passes them individually
for each tests which causes variations in the call signature between
the tests.

Add struct input_params to hold all input parameters. It can be easily
passed to every test without varying the call signature.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 6c8cb747 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Restore the CPU affinity after CAT test

CAT test does not reset the CPU affinity after the benchmark.
This is relatively harmless as is because CAT test is the last
benchmark to run, however, more tests may be added later.

Store the CPU affinity the first time taskset_benchmark() is run and
add taskset_restore() which the test can call to reset the CPU mask to
its original value.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 205de6dd 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Rewrite Cache Allocation Technology (CAT) test

CAT test spawns two processes into two different control groups with
exclusive schemata. Both the processes alloc a buffer from memory
matching their allocated LLC block size and flush the entire buffer out
of caches. Since the processes are reading through the buffer only once
during the measurement and initially all the buffer was flushed, the
test isn't testing CAT.

Rewrite the CAT test to allocate a buffer sized to half of LLC. Then
perform a sequence of tests with different LLC alloc sizes starting
from half of the CBM bits down to 1-bit CBM. Flush the buffer before
each test and read the buffer twice. Observe the LLC misses on the
second read through the buffer. As the allocated LLC block gets smaller
and smaller, the LLC misses will become larger and larger giving a
strong signal on CAT working properly.

The new CAT test is using only a single process because it relies on
measured effect against another run of itself rather than another
process adding noise. The rest of the system is set to use the CBM bits
not used by the CAT test to keep the test isolated.

Replace count_bits() with count_contiguous_bits() to get the first bit
position in order to be able to calculate masks based on it.

This change has been tested with a number of systems from different
generations.

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 2892731e 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Open perf fd before start & add error handling

Perf fd (pe_fd) is opened, reset, and enabled during every test the CAT
selftest runs. Also, ioctl(pe_fd, ...) calls are not error checked even
if ioctl() could return an error.

Open perf fd only once before the tests and only reset and enable the
counter within the test loop. Add error checking to pe_fd ioctl()
calls.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 433f437b 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Move cat_val() to cat_test.c and rename to cat_test()

The main CAT test function is called cat_val() and resides in cache.c
which is illogical.

Rename the function to cat_test() and move it into cat_test.c.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 33403bc7 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Remove unnecessary __u64 -> unsigned long conversion

Perf counters are __u64 but the code converts them to unsigned long
before printing them out.

Remove unnecessary type conversion and retain the perf originating
value as __u64.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 5caf1b64 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Split show_cache_info() to test specific and generic parts

show_cache_info() calculates results and provides generic cache
information. This makes it hard to alter pass/fail conditions.

Separate the test specific checks into CAT and CMT test files and
leave only the generic information part into show_cache_info().

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# b6dfac94 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Exclude shareable bits from schemata in CAT test

CAT test doesn't take shareable bits into account, i.e., the test might
be sharing cache with some devices (e.g., graphics).

Introduce get_mask_no_shareable() and use it to provision an
environment for CAT test where the allocated LLC is isolated better.
Excluding shareable_bits may create hole(s) into the cbm_mask, thus add
a new helper count_contiguous_bits() to find the longest contiguous set
of CBM bits.

create_bit_mask() is needed by an upcoming CAT test rewrite so make it
available in resctrl.h right away.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 19e94a23 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Create cache_portion_size() helper

CAT and CMT tests calculate size of the cache portion for the n-bits
cache allocation on their own.

Add cache_portion_size() helper that calculates size of the cache
portion for the given number of bits and use it to replace the existing
span calculations. This also prepares for the new CAT test that will
need to determine the size of the cache portion also during results
processing.

Rename also 'cache_size' local variables to 'cache_total_size' to
prevent misinterpretations.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 4b357e2a 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Refactor get_cbm_mask() and rename to get_full_cbm()

Callers of get_cbm_mask() are required to pass a string into which the
capacity bitmask (CBM) is read. Neither CAT nor CMT tests need the
bitmask as string but just convert it into an unsigned long value.

Another limitation is that the bit mask reader can only read
.../cbm_mask files.

Generalize the bit mask reading function into get_bit_mask() such that
it can be used to handle other files besides the .../cbm_mask and
handles the unsigned long conversion within get_bit_mask() using
fscanf(). Change get_cbm_mask() to use get_bit_mask() and rename it to
get_full_cbm() to better indicate what the function does.

Return error from get_full_cbm() if the bitmask is zero for some reason
because it makes the code more robust as the selftests naturally assume
the bitmask has some bits.

Also mark cache_type const while at it and remove useless comments that
are related to processing of CBM bits.

Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# c90fba60 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Return -1 instead of errno on error

A number of functions in the resctrl selftests return errno. It is
problematic because errno is positive which is often counterintuitive.
Also, every site returning errno prints the error message already with
ksft_perror() so there is not much added value in returning the precise
error code.

Simply convert all places returning errno to return -1 that is typical
userspace error code in case of failures.

While at it, improve resctrl_val() comment to state that 0 means the
test was run (either pass or fail).

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# cc8ff7f5 15-Dec-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Convert perror() to ksft_perror() or ksft_print_msg()

The resctrl selftest code contains a number of perror() calls. Some of
them come with hash character and some don't. The kselftest framework
provides ksft_perror() that is compatible with test output formatting
so it should be used instead of adding custom hash signs.

Some perror() calls are too far away from anything that sets error.
For those call sites, ksft_print_msg() must be used instead.

Convert perror() to ksft_perror() or ksft_print_msg().

Other related changes:
- Remove hash signs
- Remove trailing stops & newlines from ksft_perror()
- Add terminating newlines for converted ksft_print_msg()
- Use consistent capitalization
- Small fixes/tweaks to typos & grammar of the messages
- Extract error printing out of PARENT_EXIT() to be able to
differentiate

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 3aff5146 01-Oct-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Extend signal handler coverage to unmount on receiving signal

Unmounting resctrl FS has been moved into the per test functions in
resctrl_tests.c by commit caddc0fbe495 ("selftests/resctrl: Move
resctrl FS mount/umount to higher level"). In case a signal (SIGINT,
SIGTERM, or SIGHUP) is received, the running selftest is aborted by
ctrlc_handler() which then unmounts resctrl fs before exiting. The
current section between signal_handler_register() and
signal_handler_unregister(), however, does not cover the entire
duration when resctrl FS is mounted.

Move signal_handler_register() and signal_handler_unregister() calls
from per test files into resctrl_tests.c to properly unmount resctrl
fs. In order to not add signal_handler_register()/unregister() n times,
create helpers test_prepare() and test_cleanup().

Do not call ksft_exit_fail_msg() in test_prepare() but only in the per
test function to keep the control flow cleaner without adding calls to
exit() deep into the call chain.

Adjust child process kill() call in ctrlc_handler() to only be invoked
if the child was already forked.

Fixes: caddc0fbe495 ("selftests/resctrl: Move resctrl FS mount/umount to higher level")
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# b1a901e0 03-Sep-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Simplify span lifetime

struct resctrl_val_param contains span member. resctrl_val(), however,
never uses it because the value of span is embedded into the default
benchmark command and parsed from it by run_benchmark().

Remove span from resctrl_val_param. Provide DEFAULT_SPAN for the code
that needs it. CMT and CAT tests communicate span that is different
from the DEFAULT_SPAN between their internal functions which is
converted into passing it directly as a parameter.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: "Wieczor-Retman, Maciej" <maciej.wieczor-retman@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 3dad011b 17-Jul-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

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

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 <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan (Fujitsu) <tan.shaopeng@fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 85b73447 17-Jul-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

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

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 <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan (Fujitsu) <tan.shaopeng@fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 8ee592a6 17-Jul-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

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

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 <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan (Fujitsu) <tan.shaopeng@fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 48f3b687 17-Jul-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Remove mum_resctrlfs from struct resctrl_val_param

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 <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan (Fujitsu) <tan.shaopeng@fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# caddc0fb 17-Jul-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

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

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 <ilpo.jarvinen@linux.intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan (Fujitsu) <tan.shaopeng@fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 73c55fa5 13-Apr-2023 Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>

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

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 <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 39e34ddc 13-Apr-2023 Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>

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

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 <reinette.chatre@intel.com>
Signed-off-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# a080b6e7 13-Apr-2023 Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>

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

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 <skhan@linuxfoundation.org>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# a967e17f 15-Feb-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

selftests/resctrl: Use remount_resctrlfs() consistently with boolean

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 <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# fa10366c 15-Feb-2023 Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

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

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 <ilpo.jarvinen@linux.intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 6220f69e 23-Mar-2022 Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>

selftests/resctrl: Extend CPU vendor detection

Currently, the resctrl_tests only has a function to detect AMD vendor.
Since when the Intel Sub-NUMA Clustering feature is enabled,
Intel CMT and MBM counters may not be accurate,
the resctrl_tests also need a function to detect Intel vendor.
And in the future, resctrl_tests will need a function to detect different
vendors, such as Arm.

Extend the function to detect Intel vendor as well. Also,
this function can be easily extended to detect other vendors.

Signed-off-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# f1dd7198 16-Mar-2021 Fenghua Yu <fenghua.yu@intel.com>

selftests/resctrl: Skip the test if requested resctrl feature is not supported

There could be two reasons why a resctrl feature might not be enabled on
the platform
1. H/W might not support the feature
2. Even if the H/W supports it, the user might have disabled the feature
through kernel command line arguments

Hence, any resctrl unit test (like cmt, cat, mbm and mba) before starting
the test will first check if the feature is enabled on the platform or not.
If the feature isn't enabled, then the test returns with an error status.
For example, if MBA isn't supported on a platform and if the user tries to
run MBA, the output will look like this

ok mounting resctrl to "/sys/fs/resctrl"
not ok MBA: schemata change

But, not supporting a feature isn't a test failure. So, instead of treating
it as an error, use the SKIP directive of the TAP protocol. With the
change, the output will look as below

ok MBA # SKIP Hardware does not support MBA or MBA is disabled

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 09a67934 16-Mar-2021 Fenghua Yu <fenghua.yu@intel.com>

selftests/resctrl: Don't hard code value of "no_of_bits" variable

Cache related tests (like CAT and CMT) depend on a variable called
no_of_bits to run. no_of_bits defines the number of contiguous bits
that should be set in the CBM mask and a user can pass a value for
no_of_bits using -n command line argument. If a user hasn't passed any
value, it defaults to 5 (randomly chosen value).

Hard coding no_of_bits to 5 will make the cache tests fail to run on
systems that support maximum cbm mask that is less than or equal to 5 bits.
Hence, don't hard code no_of_bits value.

If a user passes a value for "no_of_bits" using -n option, use it.
Otherwise, no_of_bits is equal to half of the maximum number of bits in
the cbm mask.

Please note that CMT test is still hard coded to 5 bits. It will change in
subsequent patches that change CMT test.

Tested-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 03216ed7 16-Mar-2021 Fenghua Yu <fenghua.yu@intel.com>

selftests/resctrl: Share show_cache_info() by CAT and CMT tests

show_cache_info() functions are defined separately in CAT and CMT
tests. But the functions are same for the tests and unnecessary
to be defined separately. Share the function by the tests.

Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Tested-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# ca2f4214 16-Mar-2021 Fenghua Yu <fenghua.yu@intel.com>

selftests/resctrl: Call kselftest APIs to log test results

Call kselftest APIs instead of using printf() to log test results
for cleaner code and better future extension.

Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Tested-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 24286736 16-Mar-2021 Fenghua Yu <fenghua.yu@intel.com>

selftests/resctrl: Clean up resctrl features check

Checking resctrl features call strcmp() to compare feature strings
(e.g. "mba", "cat" etc). The checkings are error prone and don't have
good coding style. Define the constant strings in macros and call
strncmp() to solve the potential issues.

Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Tested-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 8236c51d 16-Mar-2021 Fenghua Yu <fenghua.yu@intel.com>

selftests/resctrl: Fix compilation issues for global variables

Reinette reported following compilation issue on Fedora 32, gcc version
10.1.1

/usr/bin/ld: cqm_test.o:<src_dir>/cqm_test.c:22: multiple definition of
`cache_size'; cat_test.o:<src_dir>/cat_test.c:23: first defined here

The same issue is reported for long_mask, cbm_mask, count_of_bits etc
variables as well. Compiler isn't happy because these variables are
defined globally in two .c files namely cqm_test.c and cat_test.c and
the compiler during compilation finds that the variable is already
defined (multiple definition error).

Taking a closer look at the usage of these variables reveals that these
variables are used only locally in functions such as cqm_resctrl_val()
(defined in cqm_test.c) and cat_perf_miss_val() (defined in cat_test.c).
These variables are not shared between those functions. So, there is no
need for these variables to be global. Hence, fix this issue by making
them static variables.

Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 85f553d2 16-Jan-2020 Babu Moger <babu.moger@amd.com>

selftests/resctrl: Disable MBA and MBM tests for AMD

For now, disable MBA and MBM tests for AMD. Deciding test pass/fail
is not clear right now. We can enable when we have some clarity.

Signed-off-by: Babu Moger <babu.moger@amd.com>
Co-developed-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>


# 790bf585 16-Jan-2020 Fenghua Yu <fenghua.yu@intel.com>

selftests/resctrl: Add Cache Allocation Technology (CAT) selftest

Cache Allocation Technology (CAT) selftest allocates a portion of
last level cache and starts a benchmark to read each cache
line in this portion of cache. Measure the cache misses in perf and
the misses should be equal to the number of cache lines in this
portion of cache.

We don't use CQM to calculate cache usage because some CAT enabled
platforms don't have CQM.

Co-developed-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Co-developed-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>