linux-stable.git/tools/testing/selftests/resctrl, branch linux-6.9.y

selftests/resctrl: Fix non-contiguous CBM for AMD

2024-07-11T10:50:55+00:00

[ Upstream commit 48236960c06d32370bfa6f2cc408e786873262c8 ]

The non-contiguous CBM test fails on AMD with:
Starting L3_NONCONT_CAT test ...
Mounting resctrl to "/sys/fs/resctrl"
CPUID output doesn't match 'sparse_masks' file content!
not ok 5 L3_NONCONT_CAT: test

AMD always supports non-contiguous CBM but does not report it via CPUID.

Fix the non-contiguous CBM test to use CPUID to discover non-contiguous
CBM support only on Intel.

Fixes: ae638551ab64 ("selftests/resctrl: Add non-contiguous CBMs CAT test")
Signed-off-by: Babu Moger 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

selftests/resctrl: fix clang build failure: use LOCAL_HDRS

2024-05-30T07:44:31+00:00

[ Upstream commit d8171aa4ca72f1a67bf3c14c59441d63c1d2585f ]

First of all, in order to build with clang at all, one must first apply
Valentin Obst's build fix for LLVM [1]. Once that is done, then when
building with clang, via:

    make LLVM=1 -C tools/testing/selftests

...the following error occurs:

   clang: error: cannot specify -o when generating multiple output files

This is because clang, unlike gcc, won't accept invocations of this
form:

    clang file1.c header2.h

Fix this by using selftests/lib.mk facilities for tracking local header
file dependencies: add them to LOCAL_HDRS, leaving only the .c files to
be passed to the compiler.

[1] https://lore.kernel.org/all/20240329-selftests-libmk-llvm-rfc-v1-1-2f9ed7d1c49f@valentinobst.de/

Fixes: 8e289f454289 ("selftests/resctrl: Add resctrl.h into build deps")
Cc: Ilpo Järvinen 
Signed-off-by: John Hubbard 
Acked-by: Reinette Chatre 
Signed-off-by: Shuah Khan 
Signed-off-by: Sasha Levin

selftests/resctrl: Add non-contiguous CBMs CAT test

2024-02-23T22:19:25+00:00

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 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Signed-off-by: Shuah Khan

selftests/resctrl: Add resource_info_file_exists()

2024-02-23T22:19:20+00:00

Feature checking done by resctrl_mon_feature_exists() covers features
represented by the feature name presence inside the 'mon_features' file
in /sys/fs/resctrl/info/L3_MON directory. There exists a different way
to represent feature support and that is by the presence of 0 or 1 in a
single file in the info/resource directory. In this case the filename
represents what feature support is being indicated.

Add a generic function to check file presence in the
/sys/fs/resctrl/info/ directory.

Signed-off-by: Maciej Wieczor-Retman 
Reviewed-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan

selftests/resctrl: Split validate_resctrl_feature_request()

2024-02-23T22:19:15+00:00

validate_resctrl_feature_request() is used to test both if a resource is
present in the info directory, and if a passed monitoring feature is
present in the mon_features file.

Refactor validate_resctrl_feature_request() into two smaller functions
that each accomplish one check to give feature checking more
granularity:
- Resource directory presence in the /sys/fs/resctrl/info directory.
- Feature name presence in the /sys/fs/resctrl/info//mon_features
  file.

Signed-off-by: Maciej Wieczor-Retman 
Reviewed-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan

selftests/resctrl: Add a helper for the non-contiguous test

2024-02-23T22:19:09+00:00

The CAT non-contiguous selftests have to read the file responsible for
reporting support of non-contiguous CBMs in kernel (resctrl). Then the
test compares if that information matches what is reported by CPUID
output.

Add a generic helper function to read an unsigned number from
/sys/fs/resctrl/info//.

Signed-off-by: Maciej Wieczor-Retman 
Reviewed-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan

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

2024-02-23T22:19:03+00:00

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 
Signed-off-by: Maciej Wieczor-Retman 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan

selftests/resctrl: Get domain id from cache id

2024-02-13T20:56:45+00:00

Domain id is acquired differently depending on CPU. AMD tests use id
from L3 cache, whereas CPUs from other vendors base the id on topology
package id. In order to support L2 CAT test, this has to be
generalized.

The driver side code seems to get the domain ids from cache ids so the
approach used by the AMD branch seems to match the kernel-side code. It
will also work with L2 domain IDs as long as the cache level is
generalized.

Using the topology id was always fragile due to mismatch with the
kernel-side way to acquire the domain id. It got incorrect domain id,
e.g., when Cluster-on-Die (CoD) is enabled for CPU (but CoD is not well
suited for resctrl in the first place so it has not been a big issue if
tests don't work correctly with it).

Taking all the above into account, generalize acquiring the domain id
by taking it from the cache id and do not hard-code the cache level.

Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan

selftests/resctrl: Rename resource ID to domain ID

2024-02-13T20:56:45+00:00

Kernel-side calls the instances of a resource domains.

Change the resource_id naming in the selftest code to domain_id to
match the kernel side better.

Suggested-by: Maciej Wieczór-Retman 
Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan

selftests/resctrl: Add helper to convert L2/3 to integer

2024-02-13T20:56:45+00:00

"L2"/"L3" conversion to integer is embedded into get_cache_size()
which prevents reuse.

Create a helper for the cache string to integer conversion to make
it reusable.

Signed-off-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Signed-off-by: Shuah Khan