kernel/linux.git/tools/testing/selftests/powerpc/utils.c, branch v6.3.6

selftests/powerpc: Add automatically allocating read_file

2023-02-09T12:56:45+00:00

A couple of tests roll their own auto-allocating file read logic. Add a generic implementation and convert them to use it. Signed-off-by: Benjamin Gray Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230203003947.38033-6-bgray@linux.ibm.com

selftests/powerpc: Add {read,write}_{long,ulong}

2023-02-09T12:56:45+00:00

Add helper functions to read and write (unsigned) long values directly from/to files. One of the kernel interfaces uses hex strings, so we need to allow passing a base too. Signed-off-by: Benjamin Gray Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230203003947.38033-5-bgray@linux.ibm.com

selftests/powerpc: Parse long/unsigned long value safely

2023-02-09T12:56:45+00:00

Often a file is expected to hold an integral value. Existing functions will use a C stdlib function like atoi or strtol to parse the file. These operations are error prone, with complicated error conditions (atoi returns 0 if not a number, and is undefined behaviour if not in range. strtol returns 0 if not a number, and LONG_MIN/MAX if not in range + sets errno to ERANGE). Signed-off-by: Benjamin Gray Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230203003947.38033-4-bgray@linux.ibm.com

selftests/powerpc: Add read/write debugfs file, int

2023-02-09T12:56:45+00:00

Debugfs files are not always integers, so make *_file return/write a byte buffer, and *_int deal with int values specifically. This increases consistency with the other file read/write helpers. Signed-off-by: Benjamin Gray Reviewed-by: Andrew Donnellan Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230203003947.38033-3-bgray@linux.ibm.com

selftests/powerpc: Add generic read/write file util

2023-02-09T12:56:45+00:00

File read/write is reimplemented in about 5 different ways in the various PowerPC selftests. This indicates it should be a common util. Add a common read_file / write_file implementation and convert users to it where (easily) possible. Signed-off-by: Benjamin Gray Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230203003947.38033-2-bgray@linux.ibm.com

selftests/powerpc: Move set_dscr() into rfi_flush.c

2020-09-08T12:23:57+00:00

This version of set_dscr() was added for the RFI flush test, and is fairly specific to it. It also clashes with the version of set_dscr() in dscr/dscr.h. So move it into the RFI flush test where it's used. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200819015727.1977134-3-mpe@ellerman.id.au

selftests/powerpc: Make using_hash_mmu() work on Cell & PowerMac

2020-09-08T12:23:51+00:00

These platforms don't show the MMU in /proc/cpuinfo, but they always use hash, so teach using_hash_mmu() that. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200819015727.1977134-1-mpe@ellerman.id.au

selftests/powerpc: Fix online CPU selection

2020-07-30T12:53:50+00:00

The size of the CPU affinity mask must be large enough for systems with a very large number of CPUs. Otherwise, tests which try to determine the first online CPU by calling sched_getaffinity() will fail. This makes sure that the size of the allocated affinity mask is dependent on the number of CPUs as reported by get_nprocs_conf(). Fixes: 3752e453f6ba ("selftests/powerpc: Add tests of PMU EBBs") Reported-by: Shirisha Ganta Signed-off-by: Sandipan Das Reviewed-by: Kamalesh Babulal Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/a408c4b8e9a23bb39b539417a21eb0ff47bb5127.1596084858.git.sandipan@linux.ibm.com

selftests/powerpc: Move Hash MMU check to utilities

2020-06-30T04:37:51+00:00

This moves a function to test if the MMU is in Hash mode under the generic test utilities. Signed-off-by: Sandipan Das Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200604125610.649668-3-sandipan@linux.ibm.com

selftests/powerpc: Add a test of spectre_v2 mitigations

2019-10-30T04:43:57+00:00

This test uses the PMU to count branch prediction hits/misses for a known loop, and compare the result to the reported spectre v2 mitigation. This gives us a way of sanity checking that the reported mitigation is actually in effect. Sample output for some cases, eg: Power9: sysfs reports: 'Vulnerable' PM_BR_PRED_CCACHE: result 368 running/enabled 5792777124 PM_BR_MPRED_CCACHE: result 319 running/enabled 5792775546 PM_BR_PRED_PCACHE: result 2147483281 running/enabled 5792773128 PM_BR_MPRED_PCACHE: result 213604201 running/enabled 5792771640 Miss percent 9 % OK - Measured branch prediction rates match reported spectre v2 mitigation. sysfs reports: 'Mitigation: Indirect branch serialisation (kernel only)' PM_BR_PRED_CCACHE: result 895 running/enabled 5780320920 PM_BR_MPRED_CCACHE: result 822 running/enabled 5780312414 PM_BR_PRED_PCACHE: result 2147482754 running/enabled 5780308836 PM_BR_MPRED_PCACHE: result 213639731 running/enabled 5780307912 Miss percent 9 % OK - Measured branch prediction rates match reported spectre v2 mitigation. sysfs reports: 'Mitigation: Indirect branch cache disabled' PM_BR_PRED_CCACHE: result 2147483649 running/enabled 20540186160 PM_BR_MPRED_CCACHE: result 2147483649 running/enabled 20540180056 PM_BR_PRED_PCACHE: result 0 running/enabled 20540176090 PM_BR_MPRED_PCACHE: result 0 running/enabled 20540174182 Miss percent 100 % OK - Measured branch prediction rates match reported spectre v2 mitigation. Power8: sysfs reports: 'Vulnerable' PM_BR_PRED_CCACHE: result 2147483649 running/enabled 3505888142 PM_BR_MPRED_CCACHE: result 9 running/enabled 3505882788 Miss percent 0 % OK - Measured branch prediction rates match reported spectre v2 mitigation. sysfs reports: 'Mitigation: Indirect branch cache disabled' PM_BR_PRED_CCACHE: result 2147483649 running/enabled 16931421988 PM_BR_MPRED_CCACHE: result 2147483649 running/enabled 16931416478 Miss percent 100 % OK - Measured branch prediction rates match reported spectre v2 mitigation. success: spectre_v2 Signed-off-by: Michael Ellerman Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190520105520.22274-1-mpe@ellerman.id.au