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linux/tools/testing/selftests/resctrl/resctrl.h

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selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
selftests/resctrl: Add callback to start a benchmark The callback starts a child process and puts the child pid in created resctrl group with specified memory bandwidth in schemata. The child starts running benchmark. 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> 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>
2020-01-16 13:32:37 -08:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
selftests/resctrl: Adjust effective L3 cache size with SNC enabled Sub-NUMA Cluster divides CPUs sharing an L3 cache into separate NUMA nodes. Systems may support splitting into either two, three, four or six nodes. When SNC mode is enabled the effective amount of L3 cache available for allocation is divided by the number of nodes per L3. It's possible to detect which SNC mode is active by comparing the number of CPUs that share a cache with CPU0, with the number of CPUs on node0. Detect SNC mode once and let other tests inherit that information. Update CFLAGS after including lib.mk in the Makefile so that fallthrough macro can be used. To check if SNC detection is reliable one can check the /sys/devices/system/cpu/offline file. If it's empty, it means all cores are operational and the ratio should be calculated correctly. If it has any contents, it means the detected SNC mode can't be trusted and should be disabled. Check if detection was not reliable due to offline cpus. If it was skip running tests since the results couldn't be trusted. Co-developed-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Tony Luck <tony.luck@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>
2024-12-16 16:18:53 +01:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
selftests/resctrl: Add Cache QoS Monitoring (CQM) selftest Cache QoS Monitoring (CQM) selftest starts stressful cache benchmark with specified size of memory to access the cache. Last Level cache occupancy reported by CQM should be close to the size of the memory. 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>
2020-01-16 13:32:41 -08:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
selftests/resctrl: Adjust effective L3 cache size with SNC enabled Sub-NUMA Cluster divides CPUs sharing an L3 cache into separate NUMA nodes. Systems may support splitting into either two, three, four or six nodes. When SNC mode is enabled the effective amount of L3 cache available for allocation is divided by the number of nodes per L3. It's possible to detect which SNC mode is active by comparing the number of CPUs that share a cache with CPU0, with the number of CPUs on node0. Detect SNC mode once and let other tests inherit that information. Update CFLAGS after including lib.mk in the Makefile so that fallthrough macro can be used. To check if SNC detection is reliable one can check the /sys/devices/system/cpu/offline file. If it's empty, it means all cores are operational and the ratio should be calculated correctly. If it has any contents, it means the detected SNC mode can't be trusted and should be disabled. Check if detection was not reliable due to offline cpus. If it was skip running tests since the results couldn't be trusted. Co-developed-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Tony Luck <tony.luck@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>
2024-12-16 16:18:53 +01:00
selftests/resctrl: Define CPU vendor IDs as bits to match usage The CPU vendor IDs are required to be unique bits because they're used for vendor_specific bitmask in the struct resctrl_test. Consider for example their usage in test_vendor_specific_check(): return get_vendor() & test->vendor_specific However, the definitions of CPU vendor IDs in file resctrl.h is quite subtle as a bitmask value: #define ARCH_INTEL 1 #define ARCH_AMD 2 A clearer and more maintainable approach is to define these CPU vendor IDs using BIT(). This ensures each vendor corresponds to a distinct bit and makes it obvious when adding new vendor IDs. Accordingly, update the return types of detect_vendor() and get_vendor() from 'int' to 'unsigned int' to align with their usage as bitmask values and to prevent potentially risky type conversions. Furthermore, introduce a bool flag 'initialized' to simplify the get_vendor() -> detect_vendor() logic. This ensures the vendor ID is detected only once and resolves the ambiguity of using the same variable 'vendor' both as a value and as a state. Link: https://lore.kernel.org/r/20251217030456.3834956-3-shenxiaochen@open-hieco.net Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Suggested-by: Fenghua Yu <fenghuay@nvidia.com> Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-12-17 11:04:54 +08:00
selftests: complete kselftest include centralization This follow-up patch completes centralization of kselftest.h and ksefltest_harness.h includes in remaining seltests files, replacing all relative paths with a non-relative paths using shared -I include path in lib.mk Tested with gcc-13.3 and clang-18.1, and cross-compiled successfully on riscv, arm64, x86_64 and powerpc arch. [reddybalavignesh9979@gmail.com: add selftests include path for kselftest.h] Link: https://lkml.kernel.org/r/20251017090201.317521-1-reddybalavignesh9979@gmail.com Link: https://lkml.kernel.org/r/20251016104409.68985-1-reddybalavignesh9979@gmail.com Signed-off-by: Bala-Vignesh-Reddy <reddybalavignesh9979@gmail.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lore.kernel.org/lkml/20250820143954.33d95635e504e94df01930d0@linux-foundation.org/ Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Günther Noack <gnoack@google.com> Cc: Jakub Kacinski <kuba@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mickael Salaun <mic@digikod.net> Cc: Ming Lei <ming.lei@redhat.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Simon Horman <horms@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-16 16:14:09 +05:30
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
selftests/resctrl: Add callback to start a benchmark The callback starts a child process and puts the child pid in created resctrl group with specified memory bandwidth in schemata. The child starts running benchmark. 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> 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>
2020-01-16 13:32:37 -08:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
selftests/resctrl: Change name from CBM_MASK_PATH to INFO_PATH CBM_MASK_PATH is actually the path to resctrl/info. Change the macro name to correctly indicate what it represents. [ ij: Tweaked the changelog. ] 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>
2023-02-15 15:06:03 +02:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
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>
2023-12-15 17:05:11 +02:00
selftests/resctrl: Define CPU vendor IDs as bits to match usage The CPU vendor IDs are required to be unique bits because they're used for vendor_specific bitmask in the struct resctrl_test. Consider for example their usage in test_vendor_specific_check(): return get_vendor() & test->vendor_specific However, the definitions of CPU vendor IDs in file resctrl.h is quite subtle as a bitmask value: #define ARCH_INTEL 1 #define ARCH_AMD 2 A clearer and more maintainable approach is to define these CPU vendor IDs using BIT(). This ensures each vendor corresponds to a distinct bit and makes it obvious when adding new vendor IDs. Accordingly, update the return types of detect_vendor() and get_vendor() from 'int' to 'unsigned int' to align with their usage as bitmask values and to prevent potentially risky type conversions. Furthermore, introduce a bool flag 'initialized' to simplify the get_vendor() -> detect_vendor() logic. This ensures the vendor ID is detected only once and resolves the ambiguity of using the same variable 'vendor' both as a value and as a state. Link: https://lore.kernel.org/r/20251217030456.3834956-3-shenxiaochen@open-hieco.net Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Suggested-by: Fenghua Yu <fenghuay@nvidia.com> Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-12-17 11:04:54 +08:00
selftests/resctrl: Add CPU vendor detection for Hygon The resctrl selftest currently fails on Hygon CPUs that support Platform QoS features, printing the error: "# Can not get vendor info..." This occurs because vendor detection is missing for Hygon CPUs. Fix this by extending the CPU vendor detection logic to include Hygon's vendor ID. Link: https://lore.kernel.org/r/20251217030456.3834956-4-shenxiaochen@open-hieco.net Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-12-17 11:04:55 +08:00
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>
2022-03-23 17:09:27 +09:00
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>
2023-02-15 15:05:59 +02:00
selftests/resctrl: Make benchmark command const and build it with pointers Benchmark command is used in multiple tests so it should not be mutated by the tests but CMT test alters span argument. Due to the order of tests (CMT test runs last), mutating the span argument in CMT test does not trigger any real problems currently. Mark benchmark_cmd strings as const and setup the benchmark command using pointers. Because the benchmark command becomes const, the input arguments can be used directly. Besides being simpler, using the input arguments directly also removes the internal size restriction. CMT test has to create a copy of the benchmark command before altering the benchmark command. 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> Reviewed-by: "Wieczor-Retman, Maciej" <maciej.wieczor-retman@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-09-04 12:53:37 +03:00
selftests/resctrl: Use cache size to determine "fill_buf" buffer size By default the MBM and MBA tests use the "fill_buf" benchmark to read from a buffer with the goal to measure the memory bandwidth generated by this buffer access. Care should be taken when sizing the buffer used by the "fill_buf" benchmark. If the buffer is small enough to fit in the cache then it cannot be expected that the benchmark will generate much memory bandwidth. For example, on a system with 320MB L3 cache the existing hardcoded default of 250MB is insufficient. Use the measured cache size to determine a buffer size that can be expected to trigger memory access while keeping the existing default as minimum, now renamed to MINIMUM_SPAN, that has been appropriate for testing so far. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:49 -07:00
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>
2023-09-04 12:53:35 +03:00
selftests/resctrl: Do not compare performance counters and resctrl at low bandwidth The MBA test incrementally throttles memory bandwidth, each time followed by a comparison between the memory bandwidth observed by the performance counters and resctrl respectively. While a comparison between performance counters and resctrl is generally appropriate, they do not have an identical view of memory bandwidth. For example RAS features or memory performance features that generate memory traffic may drive accesses that are counted differently by performance counters and MBM respectively, for instance generating "overhead" traffic which is not counted against any specific RMID. As a ratio, this different view of memory bandwidth becomes more apparent at low memory bandwidths. It is not practical to enable/disable the various features that may generate memory bandwidth to give performance counters and resctrl an identical view. Instead, do not compare performance counters and resctrl view of memory bandwidth when the memory bandwidth is low. Bandwidth throttling behaves differently across platforms so it is not appropriate to drop measurement data simply based on the throttling level. Instead, use a threshold of 750MiB that has been observed to support adequate comparison between performance counters and resctrl. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:50 -07:00
selftests/resctrl: Raise threshold at which MBM and PMU values are compared Commit 501cfdba0a40 ("selftests/resctrl: Do not compare performance counters and resctrl at low bandwidth") introduced a threshold under which memory bandwidth values from MBM and performance counters are not compared. This is needed because MBM and the PMUs do not have an identical view of memory bandwidth since PMUs can count all memory traffic while MBM does not count "overhead" (for example RAS) traffic that cannot be attributed to an RMID. As a ratio this difference in view of memory bandwidth is pronounced at low memory bandwidths. The 750MiB threshold was chosen arbitrarily after comparisons on different platforms. Exposed to more platforms after introduction this threshold has proven to be inadequate. Having accurate comparison between performance counters and MBM requires careful management of system load as well as control of features that introduce extra memory traffic, for example, patrol scrub. This is not appropriate for the resctrl selftests that are intended to run on a variety of systems with various configurations. Increase the memory bandwidth threshold under which no comparison is made between performance counters and MBM. Add additional leniency by increasing the percentage of difference that will be tolerated between these counts. There is no impact to the validity of the resctrl selftests results as a measure of resctrl subsystem health. Link: https://lore.kernel.org/r/b374c33ddd324130d6255cbb91c3dd500e8277e7.1775266384.git.reinette.chatre@intel.com Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Chen Yu <yu.c.chen@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-03 18:56:06 -07:00
selftests/resctrl: Do not compare performance counters and resctrl at low bandwidth The MBA test incrementally throttles memory bandwidth, each time followed by a comparison between the memory bandwidth observed by the performance counters and resctrl respectively. While a comparison between performance counters and resctrl is generally appropriate, they do not have an identical view of memory bandwidth. For example RAS features or memory performance features that generate memory traffic may drive accesses that are counted differently by performance counters and MBM respectively, for instance generating "overhead" traffic which is not counted against any specific RMID. As a ratio, this different view of memory bandwidth becomes more apparent at low memory bandwidths. It is not practical to enable/disable the various features that may generate memory bandwidth to give performance counters and resctrl an identical view. Instead, do not compare performance counters and resctrl view of memory bandwidth when the memory bandwidth is low. Bandwidth throttling behaves differently across platforms so it is not appropriate to drop measurement data simply based on the throttling level. Instead, use a threshold of 750MiB that has been observed to support adequate comparison between performance counters and resctrl. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:50 -07:00
selftests/resctrl: Make benchmark parameter passing robust The benchmark used during the CMT, MBM, and MBA tests can be provided by the user via (-b) parameter, if not provided the default "fill_buf" benchmark is used. The user is additionally able to override any of the "fill_buf" default parameters when running the tests with "-b fill_buf <fill_buf parameters>". The "fill_buf" parameters are managed as an array of strings. Using an array of strings is complex because it requires transformations to/from strings at every producer and consumer. This is made worse for the individual tests where the default benchmark parameters values may not be appropriate and additional data wrangling is required. For example, the CMT test duplicates the entire array of strings in order to replace one of the parameters. More issues appear when combining the usage of an array of strings with the use case of user overriding default parameters by specifying "-b fill_buf <parameters>". This use case is fragile with opportunities to trigger a SIGSEGV because of opportunities for NULL pointers to exist in the array of strings. For example, by running below (thus by specifying "fill_buf" should be used but all parameters are NULL): $ sudo resctrl_tests -t mbm -b fill_buf Replace the "array of strings" parameters used for "fill_buf" with new struct fill_buf_param that contains the "fill_buf" parameters that can be used directly without transformations to/from strings. Two instances of struct fill_buf_param may exist at any point in time: * If the user provides new parameters to "fill_buf", the user parameter structure (struct user_params) will point to a fully initialized and immutable struct fill_buf_param containing the user provided parameters. * If "fill_buf" is the benchmark that should be used by a test, then the test parameter structure (struct resctrl_val_param) will point to a fully initialized struct fill_buf_param. The latter may contain (a) the user provided parameters verbatim, (b) user provided parameters adjusted to be appropriate for the test, or (c) the default parameters for "fill_buf" that is appropriate for the test if the user did not provide "fill_buf" parameters nor an alternate benchmark. The existing behavior of CMT test is to use test defined value for the buffer size even if the user provides another value via command line. This behavior is maintained since the test requires that the buffer size matches the size of the cache allocated, and the amount of cache allocated can instead be changed by the user with the "-n" command line parameter. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:47 -07:00
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>
2023-12-15 17:05:10 +02:00
selftests/resctrl: Make benchmark parameter passing robust The benchmark used during the CMT, MBM, and MBA tests can be provided by the user via (-b) parameter, if not provided the default "fill_buf" benchmark is used. The user is additionally able to override any of the "fill_buf" default parameters when running the tests with "-b fill_buf <fill_buf parameters>". The "fill_buf" parameters are managed as an array of strings. Using an array of strings is complex because it requires transformations to/from strings at every producer and consumer. This is made worse for the individual tests where the default benchmark parameters values may not be appropriate and additional data wrangling is required. For example, the CMT test duplicates the entire array of strings in order to replace one of the parameters. More issues appear when combining the usage of an array of strings with the use case of user overriding default parameters by specifying "-b fill_buf <parameters>". This use case is fragile with opportunities to trigger a SIGSEGV because of opportunities for NULL pointers to exist in the array of strings. For example, by running below (thus by specifying "fill_buf" should be used but all parameters are NULL): $ sudo resctrl_tests -t mbm -b fill_buf Replace the "array of strings" parameters used for "fill_buf" with new struct fill_buf_param that contains the "fill_buf" parameters that can be used directly without transformations to/from strings. Two instances of struct fill_buf_param may exist at any point in time: * If the user provides new parameters to "fill_buf", the user parameter structure (struct user_params) will point to a fully initialized and immutable struct fill_buf_param containing the user provided parameters. * If "fill_buf" is the benchmark that should be used by a test, then the test parameter structure (struct resctrl_val_param) will point to a fully initialized struct fill_buf_param. The latter may contain (a) the user provided parameters verbatim, (b) user provided parameters adjusted to be appropriate for the test, or (c) the default parameters for "fill_buf" that is appropriate for the test if the user did not provide "fill_buf" parameters nor an alternate benchmark. The existing behavior of CMT test is to use test defined value for the buffer size even if the user provides another value via command line. This behavior is maintained since the test requires that the buffer size matches the size of the cache allocated, and the amount of cache allocated can instead be changed by the user with the "-n" command line parameter. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:47 -07:00
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>
2023-12-15 17:05:10 +02:00
selftests/resctrl: Make benchmark parameter passing robust The benchmark used during the CMT, MBM, and MBA tests can be provided by the user via (-b) parameter, if not provided the default "fill_buf" benchmark is used. The user is additionally able to override any of the "fill_buf" default parameters when running the tests with "-b fill_buf <fill_buf parameters>". The "fill_buf" parameters are managed as an array of strings. Using an array of strings is complex because it requires transformations to/from strings at every producer and consumer. This is made worse for the individual tests where the default benchmark parameters values may not be appropriate and additional data wrangling is required. For example, the CMT test duplicates the entire array of strings in order to replace one of the parameters. More issues appear when combining the usage of an array of strings with the use case of user overriding default parameters by specifying "-b fill_buf <parameters>". This use case is fragile with opportunities to trigger a SIGSEGV because of opportunities for NULL pointers to exist in the array of strings. For example, by running below (thus by specifying "fill_buf" should be used but all parameters are NULL): $ sudo resctrl_tests -t mbm -b fill_buf Replace the "array of strings" parameters used for "fill_buf" with new struct fill_buf_param that contains the "fill_buf" parameters that can be used directly without transformations to/from strings. Two instances of struct fill_buf_param may exist at any point in time: * If the user provides new parameters to "fill_buf", the user parameter structure (struct user_params) will point to a fully initialized and immutable struct fill_buf_param containing the user provided parameters. * If "fill_buf" is the benchmark that should be used by a test, then the test parameter structure (struct resctrl_val_param) will point to a fully initialized struct fill_buf_param. The latter may contain (a) the user provided parameters verbatim, (b) user provided parameters adjusted to be appropriate for the test, or (c) the default parameters for "fill_buf" that is appropriate for the test if the user did not provide "fill_buf" parameters nor an alternate benchmark. The existing behavior of CMT test is to use test defined value for the buffer size even if the user provides another value via command line. This behavior is maintained since the test requires that the buffer size matches the size of the cache allocated, and the amount of cache allocated can instead be changed by the user with the "-n" command line parameter. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:47 -07:00
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>
2023-12-15 17:05:10 +02:00
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>
2023-12-15 17:05:11 +02:00
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>
2024-02-16 09:34:56 +01:00
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>
2023-12-15 17:05:11 +02:00
selftests/resctrl: Add cleanup function to test framework Resctrl selftests use very similar functions to cleanup after themselves. This creates a lot of code duplication. Also not being hooked to the test framework means that ctrl-c handler isn't aware of what test is currently running and executes all cleanups even though only one is needed. Add a function pointer to the resctrl_test struct and attach to it cleanup functions from individual tests. 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>
2024-02-27 08:21:41 +01:00
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>
2023-12-15 17:05:11 +02:00
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>
2024-02-16 09:34:56 +01:00
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>
2023-12-15 17:05:11 +02:00
selftests/resctrl: Add cleanup function to test framework Resctrl selftests use very similar functions to cleanup after themselves. This creates a lot of code duplication. Also not being hooked to the test framework means that ctrl-c handler isn't aware of what test is currently running and executes all cleanups even though only one is needed. Add a function pointer to the resctrl_test struct and attach to it cleanup functions from individual tests. 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>
2024-02-27 08:21:41 +01:00
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>
2023-12-15 17:05:11 +02:00
selftests/resctrl: Add callback to start a benchmark The callback starts a child process and puts the child pid in created resctrl group with specified memory bandwidth in schemata. The child starts running benchmark. 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> 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>
2020-01-16 13:32:37 -08:00
selftests/resctrl: Add ->init() callback into resctrl_val_param The struct resctrl_val_param is there to customize behavior inside resctrl_val() which is currently not used to full extent and there are number of strcmp()s for test name in resctrl_val done by resctrl_val(). Create ->init() hook into the struct resctrl_val_param to cleanly do per test initialization. Remove also unused branches to setup paths and the related #defines for CMT test. While touching kerneldoc, make the adjacent line consistent with the newly added form (callback vs call back). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-06-10 18:14:51 +03:00
selftests/resctrl: Add ->measure() callback to resctrl_val_param The measurement done in resctrl_val() varies depending on test type. The decision for how to measure is decided based on the string compare to test name which is quite inflexible. Add ->measure() callback into the struct resctrl_val_param to allow each test to provide necessary code as a function which simplifies what resctrl_val() has to do. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-06-10 18:14:50 +03:00
selftests/resctrl: Make benchmark parameter passing robust The benchmark used during the CMT, MBM, and MBA tests can be provided by the user via (-b) parameter, if not provided the default "fill_buf" benchmark is used. The user is additionally able to override any of the "fill_buf" default parameters when running the tests with "-b fill_buf <fill_buf parameters>". The "fill_buf" parameters are managed as an array of strings. Using an array of strings is complex because it requires transformations to/from strings at every producer and consumer. This is made worse for the individual tests where the default benchmark parameters values may not be appropriate and additional data wrangling is required. For example, the CMT test duplicates the entire array of strings in order to replace one of the parameters. More issues appear when combining the usage of an array of strings with the use case of user overriding default parameters by specifying "-b fill_buf <parameters>". This use case is fragile with opportunities to trigger a SIGSEGV because of opportunities for NULL pointers to exist in the array of strings. For example, by running below (thus by specifying "fill_buf" should be used but all parameters are NULL): $ sudo resctrl_tests -t mbm -b fill_buf Replace the "array of strings" parameters used for "fill_buf" with new struct fill_buf_param that contains the "fill_buf" parameters that can be used directly without transformations to/from strings. Two instances of struct fill_buf_param may exist at any point in time: * If the user provides new parameters to "fill_buf", the user parameter structure (struct user_params) will point to a fully initialized and immutable struct fill_buf_param containing the user provided parameters. * If "fill_buf" is the benchmark that should be used by a test, then the test parameter structure (struct resctrl_val_param) will point to a fully initialized struct fill_buf_param. The latter may contain (a) the user provided parameters verbatim, (b) user provided parameters adjusted to be appropriate for the test, or (c) the default parameters for "fill_buf" that is appropriate for the test if the user did not provide "fill_buf" parameters nor an alternate benchmark. The existing behavior of CMT test is to use test defined value for the buffer size even if the user provides another value via command line. This behavior is maintained since the test requires that the buffer size matches the size of the cache allocated, and the amount of cache allocated can instead be changed by the user with the "-n" command line parameter. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:47 -07:00
selftests/resctrl: Add callback to start a benchmark The callback starts a child process and puts the child pid in created resctrl group with specified memory bandwidth in schemata. The child starts running benchmark. 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> 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>
2020-01-16 13:32:37 -08:00
selftests/resctrl: Make benchmark parameter passing robust The benchmark used during the CMT, MBM, and MBA tests can be provided by the user via (-b) parameter, if not provided the default "fill_buf" benchmark is used. The user is additionally able to override any of the "fill_buf" default parameters when running the tests with "-b fill_buf <fill_buf parameters>". The "fill_buf" parameters are managed as an array of strings. Using an array of strings is complex because it requires transformations to/from strings at every producer and consumer. This is made worse for the individual tests where the default benchmark parameters values may not be appropriate and additional data wrangling is required. For example, the CMT test duplicates the entire array of strings in order to replace one of the parameters. More issues appear when combining the usage of an array of strings with the use case of user overriding default parameters by specifying "-b fill_buf <parameters>". This use case is fragile with opportunities to trigger a SIGSEGV because of opportunities for NULL pointers to exist in the array of strings. For example, by running below (thus by specifying "fill_buf" should be used but all parameters are NULL): $ sudo resctrl_tests -t mbm -b fill_buf Replace the "array of strings" parameters used for "fill_buf" with new struct fill_buf_param that contains the "fill_buf" parameters that can be used directly without transformations to/from strings. Two instances of struct fill_buf_param may exist at any point in time: * If the user provides new parameters to "fill_buf", the user parameter structure (struct user_params) will point to a fully initialized and immutable struct fill_buf_param containing the user provided parameters. * If "fill_buf" is the benchmark that should be used by a test, then the test parameter structure (struct resctrl_val_param) will point to a fully initialized struct fill_buf_param. The latter may contain (a) the user provided parameters verbatim, (b) user provided parameters adjusted to be appropriate for the test, or (c) the default parameters for "fill_buf" that is appropriate for the test if the user did not provide "fill_buf" parameters nor an alternate benchmark. The existing behavior of CMT test is to use test defined value for the buffer size even if the user provides another value via command line. This behavior is maintained since the test requires that the buffer size matches the size of the cache allocated, and the amount of cache allocated can instead be changed by the user with the "-n" command line parameter. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:47 -07:00
selftests/resctrl: Improve accuracy of cache occupancy test Dave Martin reported inconsistent CMT test failures. In one experiment the first run of the CMT test failed because of too large (24%) difference between measured and achievable cache occupancy while the second run passed with an acceptable 4% difference. The CMT test is susceptible to interference from the rest of the system. This can be demonstrated with a utility like stress-ng by running the CMT test while introducing cache misses using: stress-ng --matrix-3d 0 --matrix-3d-zyx Below shows an example of the CMT test failing because of a significant difference between measured and achievable cache occupancy when run with interference: # Starting CMT test ... # Mounting resctrl to "/sys/fs/resctrl" # Cache size :335544320 # Writing benchmark parameters to resctrl FS # Benchmark PID: 7011 # Checking for pass/fail # Fail: Check cache miss rate within 15% # Percent diff=99 # Number of bits: 5 # Average LLC val: 235929 # Cache span (bytes): 83886080 not ok 1 CMT: test The CMT test creates a new control group that is also capable of monitoring and assigns the workload to it. The workload allocates a buffer that by default fills a portion of the L3 and keeps reading from the buffer, measuring the L3 occupancy at intervals. The test passes if the workload's L3 occupancy is within 15% of the buffer size. By not adjusting any capacity bitmasks the workload shares the cache with the rest of the system. Any other task that may be running could evict the workload's data from the cache causing it to have low cache occupancy. Reduce interference from the rest of the system by ensuring that the workload's control group uses the capacity bitmask found in the user parameters for L3 and that the rest of the system can only allocate into the inverse of the workload's L3 cache portion. Other tasks can thus no longer evict the workload's data from L3. With the above adjustments the CMT test is more consistent. Repeating the CMT test while generating interference with stress-ng on a sample system after applying the fixes show significant improvement in test accuracy: # Starting CMT test ... # Mounting resctrl to "/sys/fs/resctrl" # Cache size :335544320 # Writing benchmark parameters to resctrl FS # Write schema "L3:0=fffe0" to resctrl FS # Write schema "L3:0=1f" to resctrl FS # Benchmark PID: 7089 # Checking for pass/fail # Pass: Check cache miss rate within 15% # Percent diff=12 # Number of bits: 5 # Average LLC val: 73269248 # Cache span (bytes): 83886080 ok 1 CMT: test Link: https://lore.kernel.org/r/b160592179f88069cdc679563e152007998a0d76.1775266384.git.reinette.chatre@intel.com Reported-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Chen Yu <yu.c.chen@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/lkml/aO+7MeSMV29VdbQs@e133380.arm.com/ Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-03 18:56:00 -07:00
selftests/resctrl: Make benchmark parameter passing robust The benchmark used during the CMT, MBM, and MBA tests can be provided by the user via (-b) parameter, if not provided the default "fill_buf" benchmark is used. The user is additionally able to override any of the "fill_buf" default parameters when running the tests with "-b fill_buf <fill_buf parameters>". The "fill_buf" parameters are managed as an array of strings. Using an array of strings is complex because it requires transformations to/from strings at every producer and consumer. This is made worse for the individual tests where the default benchmark parameters values may not be appropriate and additional data wrangling is required. For example, the CMT test duplicates the entire array of strings in order to replace one of the parameters. More issues appear when combining the usage of an array of strings with the use case of user overriding default parameters by specifying "-b fill_buf <parameters>". This use case is fragile with opportunities to trigger a SIGSEGV because of opportunities for NULL pointers to exist in the array of strings. For example, by running below (thus by specifying "fill_buf" should be used but all parameters are NULL): $ sudo resctrl_tests -t mbm -b fill_buf Replace the "array of strings" parameters used for "fill_buf" with new struct fill_buf_param that contains the "fill_buf" parameters that can be used directly without transformations to/from strings. Two instances of struct fill_buf_param may exist at any point in time: * If the user provides new parameters to "fill_buf", the user parameter structure (struct user_params) will point to a fully initialized and immutable struct fill_buf_param containing the user provided parameters. * If "fill_buf" is the benchmark that should be used by a test, then the test parameter structure (struct resctrl_val_param) will point to a fully initialized struct fill_buf_param. The latter may contain (a) the user provided parameters verbatim, (b) user provided parameters adjusted to be appropriate for the test, or (c) the default parameters for "fill_buf" that is appropriate for the test if the user did not provide "fill_buf" parameters nor an alternate benchmark. The existing behavior of CMT test is to use test defined value for the buffer size even if the user provides another value via command line. This behavior is maintained since the test requires that the buffer size matches the size of the cache allocated, and the amount of cache allocated can instead be changed by the user with the "-n" command line parameter. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:47 -07:00
selftests/resctrl: Add callback to start a benchmark The callback starts a child process and puts the child pid in created resctrl group with specified memory bandwidth in schemata. The child starts running benchmark. 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> 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>
2020-01-16 13:32:37 -08:00
selftests/resctrl: Replace file write with volatile variable The fill_buf code prevents compiler optimizating the entire read loop away by writing the final value of the variable into a file. While it achieves the goal, writing into a file requires significant amount of work within the innermost test loop and also error handling. A simpler approach is to take advantage of volatile. Writing through a pointer to a volatile variable is enough to prevent compiler from optimizing the write away, and therefore compiler cannot remove the read loop either. Add a volatile 'value_sink' into resctrl_tests.c and make fill_buf to write into it. As a result, the error handling in fill_buf.c can be simplified. 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>
2023-12-15 17:05:06 +02:00
selftests/resctrl: Adjust effective L3 cache size with SNC enabled Sub-NUMA Cluster divides CPUs sharing an L3 cache into separate NUMA nodes. Systems may support splitting into either two, three, four or six nodes. When SNC mode is enabled the effective amount of L3 cache available for allocation is divided by the number of nodes per L3. It's possible to detect which SNC mode is active by comparing the number of CPUs that share a cache with CPU0, with the number of CPUs on node0. Detect SNC mode once and let other tests inherit that information. Update CFLAGS after including lib.mk in the Makefile so that fallthrough macro can be used. To check if SNC detection is reliable one can check the /sys/devices/system/cpu/offline file. If it's empty, it means all cores are operational and the ratio should be calculated correctly. If it has any contents, it means the detected SNC mode can't be trusted and should be disabled. Check if detection was not reliable due to offline cpus. If it was skip running tests since the results couldn't be trusted. Co-developed-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Tony Luck <tony.luck@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>
2024-12-16 16:18:53 +01:00
selftests/resctrl: Fix compilation issues for other global variables Reinette reported following compilation issue on Fedora 32, gcc version 10.1.1 /usr/bin/ld: resctrl_tests.o:<src_dir>/resctrl.h:65: multiple definition of `bm_pid'; cache.o:<src_dir>/resctrl.h:65: first defined here Other variables are ppid, tests_run, llc_occup_path, is_amd. Compiler isn't happy because these variables are defined globally in two .c files but are not declared as extern. To fix issues for the global variables, declare them as extern. Chang Log: - Split this patch from v4's patch 1 (Shuah). 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>
2021-03-17 02:22:37 +00:00
selftests/resctrl: Add Cache QoS Monitoring (CQM) selftest Cache QoS Monitoring (CQM) selftest starts stressful cache benchmark with specified size of memory to access the cache. Last Level cache occupancy reported by CQM should be close to the size of the memory. 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>
2020-01-16 13:32:41 -08:00
selftests/resctrl: Adjust effective L3 cache size with SNC enabled Sub-NUMA Cluster divides CPUs sharing an L3 cache into separate NUMA nodes. Systems may support splitting into either two, three, four or six nodes. When SNC mode is enabled the effective amount of L3 cache available for allocation is divided by the number of nodes per L3. It's possible to detect which SNC mode is active by comparing the number of CPUs that share a cache with CPU0, with the number of CPUs on node0. Detect SNC mode once and let other tests inherit that information. Update CFLAGS after including lib.mk in the Makefile so that fallthrough macro can be used. To check if SNC detection is reliable one can check the /sys/devices/system/cpu/offline file. If it's empty, it means all cores are operational and the ratio should be calculated correctly. If it has any contents, it means the detected SNC mode can't be trusted and should be disabled. Check if detection was not reliable due to offline cpus. If it was skip running tests since the results couldn't be trusted. Co-developed-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Tony Luck <tony.luck@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>
2024-12-16 16:18:53 +01:00
selftests/resctrl: Define CPU vendor IDs as bits to match usage The CPU vendor IDs are required to be unique bits because they're used for vendor_specific bitmask in the struct resctrl_test. Consider for example their usage in test_vendor_specific_check(): return get_vendor() & test->vendor_specific However, the definitions of CPU vendor IDs in file resctrl.h is quite subtle as a bitmask value: #define ARCH_INTEL 1 #define ARCH_AMD 2 A clearer and more maintainable approach is to define these CPU vendor IDs using BIT(). This ensures each vendor corresponds to a distinct bit and makes it obvious when adding new vendor IDs. Accordingly, update the return types of detect_vendor() and get_vendor() from 'int' to 'unsigned int' to align with their usage as bitmask values and to prevent potentially risky type conversions. Furthermore, introduce a bool flag 'initialized' to simplify the get_vendor() -> detect_vendor() logic. This ensures the vendor ID is detected only once and resolves the ambiguity of using the same variable 'vendor' both as a value and as a state. Link: https://lore.kernel.org/r/20251217030456.3834956-3-shenxiaochen@open-hieco.net Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Suggested-by: Fenghua Yu <fenghuay@nvidia.com> Signed-off-by: Xiaochen Shen <shenxiaochen@open-hieco.net> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2025-12-17 11:04:54 +08:00
selftests/resctrl: Add MBM test MBM (Memory Bandwidth Monitoring) test is the first implemented selftest. It starts a stressful memory bandwidth benchmark and assigns the bandwidth pid in a resctrl monitoring group. Read and compare perf IMC counter and MBM total bytes for the benchmark. The numbers should be close enough to pass the test. Default benchmark is built-in fill_buf. But users can specify their own benchmark by option "-b". We can add memory bandwidth monitoring for multiple processes in the future. 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>
2020-01-16 13:32:39 -08:00
selftests/resctrl: Get domain id from cache id 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 <ilpo.jarvinen@linux.intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2023-12-15 17:05:15 +02:00
selftests/resctrl: Refactor remount_resctrl(bool mum_resctrlfs) to mount_resctrl() Mount/umount of the resctrl FS is now paired nicely per test. Rename remount_resctrl(bool mum_resctrlfs) to mount_resctrl(). Make it unconditionally try to mount the resctrl FS and return error if resctrl FS was mounted already. While at it, group the mount/umount prototypes in the header. 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>
2023-07-17 16:14:55 +03:00
selftests/resctrl: Add callback to start a benchmark The callback starts a child process and puts the child pid in created resctrl group with specified memory bandwidth in schemata. The child starts running benchmark. 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> 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>
2020-01-16 13:32:37 -08:00
selftests/resctrl: Split validate_resctrl_feature_request() 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/<RESOURCE>/mon_features file. Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-02-16 09:35:28 +01:00
selftests/resctrl: Add resource_info_file_exists() 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/<RESOURCE> directory. Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-02-16 09:35:41 +01:00
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>
2023-12-15 17:05:11 +02:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
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>
2023-12-15 17:05:09 +02:00
selftests/resctrl: Make some strings passed to resctrlfs functions const Control group, monitor group and resctrl_val are not mutated and should not be mutated within resctrlfs.c functions. Mark this by using const char * for the arguments. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-06-10 18:14:53 +03:00
selftests/resctrl: Remove test name comparing from write_bm_pid_to_resctrl() write_bm_pid_to_resctrl() uses resctrl_val to check test name which is not a good interface generic resctrl FS functions should provide. Tests define mongrp when needed. Remove the test name check in write_bm_pid_to_resctrl() to only rely on the mongrp parameter being non-NULL. Remove write_bm_pid_to_resctrl() resctrl_val parameter and resctrl_val member from the struct resctrl_val_param that are not used anymore. Similarly, remove the test name constants that are no longer used. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-06-10 18:14:57 +03:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
selftests/resctrl: Make benchmark parameter passing robust The benchmark used during the CMT, MBM, and MBA tests can be provided by the user via (-b) parameter, if not provided the default "fill_buf" benchmark is used. The user is additionally able to override any of the "fill_buf" default parameters when running the tests with "-b fill_buf <fill_buf parameters>". The "fill_buf" parameters are managed as an array of strings. Using an array of strings is complex because it requires transformations to/from strings at every producer and consumer. This is made worse for the individual tests where the default benchmark parameters values may not be appropriate and additional data wrangling is required. For example, the CMT test duplicates the entire array of strings in order to replace one of the parameters. More issues appear when combining the usage of an array of strings with the use case of user overriding default parameters by specifying "-b fill_buf <parameters>". This use case is fragile with opportunities to trigger a SIGSEGV because of opportunities for NULL pointers to exist in the array of strings. For example, by running below (thus by specifying "fill_buf" should be used but all parameters are NULL): $ sudo resctrl_tests -t mbm -b fill_buf Replace the "array of strings" parameters used for "fill_buf" with new struct fill_buf_param that contains the "fill_buf" parameters that can be used directly without transformations to/from strings. Two instances of struct fill_buf_param may exist at any point in time: * If the user provides new parameters to "fill_buf", the user parameter structure (struct user_params) will point to a fully initialized and immutable struct fill_buf_param containing the user provided parameters. * If "fill_buf" is the benchmark that should be used by a test, then the test parameter structure (struct resctrl_val_param) will point to a fully initialized struct fill_buf_param. The latter may contain (a) the user provided parameters verbatim, (b) user provided parameters adjusted to be appropriate for the test, or (c) the default parameters for "fill_buf" that is appropriate for the test if the user did not provide "fill_buf" parameters nor an alternate benchmark. The existing behavior of CMT test is to use test defined value for the buffer size even if the user provides another value via command line. This behavior is maintained since the test requires that the buffer size matches the size of the cache allocated, and the amount of cache allocated can instead be changed by the user with the "-n" command line parameter. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:47 -07:00
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>
2023-12-15 17:05:08 +02:00
selftests/resctrl: Use cache size to determine "fill_buf" buffer size By default the MBM and MBA tests use the "fill_buf" benchmark to read from a buffer with the goal to measure the memory bandwidth generated by this buffer access. Care should be taken when sizing the buffer used by the "fill_buf" benchmark. If the buffer is small enough to fit in the cache then it cannot be expected that the benchmark will generate much memory bandwidth. For example, on a system with 320MB L3 cache the existing hardcoded default of 250MB is insufficient. Use the measured cache size to determine a buffer size that can be expected to trigger memory access while keeping the existing default as minimum, now renamed to MINIMUM_SPAN, that has been appropriate for testing so far. Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:49 -07:00
selftests/resctrl: Remove unused measurement code The MBM and MBA resctrl selftests run a benchmark during which it takes measurements of read memory bandwidth via perf. Code exists to support measurements of write memory bandwidth but there exists no path with which this code can execute. While code exists for write memory bandwidth measurement there has not yet been a use case for it. Remove this unused code. Rename relevant functions to include "read" so that it is clear that it relates only to memory bandwidth reads, while renaming the functions also add consistency by changing the "membw" instances to more prevalent "mem_bw". Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-10-24 14:18:46 -07:00
selftests/resctrl: Add ->init() callback into resctrl_val_param The struct resctrl_val_param is there to customize behavior inside resctrl_val() which is currently not used to full extent and there are number of strcmp()s for test name in resctrl_val done by resctrl_val(). Create ->init() hook into the struct resctrl_val_param to cleanly do per test initialization. Remove also unused branches to setup paths and the related #defines for CMT test. While touching kerneldoc, make the adjacent line consistent with the newly added form (callback vs call back). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-06-10 18:14:51 +03:00
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>
2023-12-15 17:05:12 +02:00
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>
2023-12-15 17:05:10 +02:00
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>
2023-12-15 17:04:56 +02:00
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>
2023-12-15 17:05:08 +02:00
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>
2023-12-15 17:04:53 +02:00
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>
2023-12-15 17:04:56 +02:00
selftests/resctrl: Mark get_cache_size() cache_type const get_cache_size() does not modify cache_type so it could be const. Mark cache_type const so that const char * can be passed to it. This prevents warnings once many of the test parameters are marked const. 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>
2023-12-15 17:04:54 +02:00
selftests/resctrl: Add a helper for the non-contiguous test 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/<RESOURCE>/<FILE>. Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-02-16 09:35:15 +01:00
selftests/resctrl: Add Cache QoS Monitoring (CQM) selftest Cache QoS Monitoring (CQM) selftest starts stressful cache benchmark with specified size of memory to access the cache. Last Level cache occupancy reported by CQM should be close to the size of the memory. 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>
2020-01-16 13:32:41 -08:00
selftests/resctrl: Simplify cleanup in ctrl-c handler Ctrl-c handler isn't aware of what test is currently running. Because of that it executes all cleanups even if they aren't necessary. Since the ctrl-c handler uses the sa_sigaction system no parameters can be passed to it as function arguments. Add a global variable to make ctrl-c handler aware of the currently run test and only execute the correct cleanup callback. 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>
2024-02-27 08:21:42 +01:00
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>
2023-04-13 16:22:58 +09:00
selftests/resctrl: Add Cache QoS Monitoring (CQM) selftest Cache QoS Monitoring (CQM) selftest starts stressful cache benchmark with specified size of memory to access the cache. Last Level cache occupancy reported by CQM should be close to the size of the memory. 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>
2020-01-16 13:32:41 -08:00
selftests/resctrl: Discover SNC kernel support and adjust messages Resctrl selftest prints a message on test failure that Sub-Numa Clustering (SNC) could be enabled and points the user to check their BIOS settings. No actual check is performed before printing that message so it is not very accurate in pinpointing a problem. When there is SNC support for kernel's resctrl subsystem and SNC is enabled then sub node files are created for each node in the resctrlfs. The sub node files exist in each regular node's L3 monitoring directory. The reliable path to check for existence of sub node files is /sys/fs/resctrl/mon_data/mon_L3_00/mon_sub_L3_00. Add helper that checks for mon_sub_L3_00 existence. Correct old messages to account for kernel support of SNC in resctrl. 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>
2024-12-16 16:18:54 +01:00
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>
2023-12-15 17:05:04 +02:00
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>
2023-12-15 17:05:05 +02:00
selftests/resctrl: Simplify perf usage in CAT test The CAT test relies on the PERF_COUNT_HW_CACHE_MISSES event to determine if modifying a cache portion size is successful. This event is configured to report the data as part of an event group, but no other events are added to the group. Remove the unnecessary PERF_FORMAT_GROUP format setting. This eliminates the need for struct perf_event_read and results in read() of the associated file descriptor to return just one value associated with the PERF_COUNT_HW_CACHE_MISSES event of interest. Link: https://lore.kernel.org/r/fb69325eba5031b735fa79effaaacd797c9c6040.1775266384.git.reinette.chatre@intel.com Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Chen Yu <yu.c.chen@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-03 18:56:08 -07:00
selftests/resctrl: Use correct type for pids A few functions receive PIDs through int arguments. PIDs variables should be of type pid_t, not int. Convert pid arguments from int to pid_t. Before printing PID, match the type to %d by casting to int which is enough for Linux (standard would allow using a longer integer type but generalizing for that would complicate the code unnecessarily, the selftest code does not need to be portable). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Tested-by: Babu Moger <babu.moger@amd.com> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-06-10 18:14:46 +03:00
selftests/resctrl: Reduce interference from L2 occupancy during cache occupancy test The CMT test creates a new control group that is also capable of monitoring and assigns the workload to it. The workload allocates a buffer that by default fills a portion of the L3 and keeps reading from the buffer, measuring the L3 occupancy at intervals. The test passes if the workload's L3 occupancy is within 15% of the buffer size. The CMT test does not take into account that some of the workload's data may land in L2/L1. Matching L3 occupancy to the size of the buffer while a portion of the buffer can be allocated into L2 is not accurate. Take the L2 cache into account to improve test accuracy: - Reduce the workload's L2 cache allocation to the minimum on systems that support L2 cache allocation. Do so with a new utility in preparation for all L3 cache allocation tests needing the same capability. - Increase the buffer size to accommodate data that may be allocated into the L2 cache. Use a buffer size double the L3 portion to keep using the L3 portion size as goal for L3 occupancy while taking into account that some of the data may be in L2. Running the CMT test on a sample system while introducing significant cache misses using "stress-ng --matrix-3d 0 --matrix-3d-zyx" shows significant improvement in L3 cache occupancy: Before: # Starting CMT test ... # Mounting resctrl to "/sys/fs/resctrl" # Cache size :335544320 # Writing benchmark parameters to resctrl FS # Write schema "L3:0=fffe0" to resctrl FS # Write schema "L3:0=1f" to resctrl FS # Benchmark PID: 7089 # Checking for pass/fail # Pass: Check cache miss rate within 15% # Percent diff=12 # Number of bits: 5 # Average LLC val: 73269248 # Cache span (bytes): 83886080 ok 1 CMT: test After: # Starting CMT test ... # Mounting resctrl to "/sys/fs/resctrl" # Cache size :335544320 # Writing benchmark parameters to resctrl FS # Write schema "L3:0=fffe0" to resctrl FS # Write schema "L3:0=1f" to resctrl FS # Write schema "L2:1=0x1" to resctrl FS # Benchmark PID: 7171 # Checking for pass/fail # Pass: Check cache miss rate within 15% # Percent diff=0 # Number of bits: 5 # Average LLC val: 83755008 # Cache span (bytes): 83886080 ok 1 CMT: test Link: https://lore.kernel.org/r/00445fa64c251b86b86023f87220ee1ad8561460.1775266384.git.reinette.chatre@intel.com Reported-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com> Tested-by: Chen Yu <yu.c.chen@intel.com> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/lkml/aO+7MeSMV29VdbQs@e133380.arm.com/ Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2026-04-03 18:56:01 -07:00
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>
2023-12-15 17:04:59 +02:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00
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>
2023-12-15 17:04:55 +02:00
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>
2023-12-15 17:05:11 +02:00
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>
2024-02-16 09:35:52 +01:00
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>
2023-12-15 17:05:11 +02:00
selftests/resctrl: Add basic resctrl file system operations and data The basic resctrl file system operations and data are added for future usage by resctrl selftest tool. 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> 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>
2020-01-16 13:32:35 -08:00