Hi all,

This series does a number of cleanups into resctrl_val() and generalizes it by removing test name specific handling from the function.

One of the changes improves MBA/MBM measurement by narrowing down the period the resctrl FS derived memory bandwidth numbers are measured over. My feel is it didn't cause noticeable difference into the numbers because they're generally good anyway except for the small number of outliers. To see the impact on outliers, I'd need to setup a test to run large number of replications and do a statistical analysis, which I've not spent my time on. Even without the statistical analysis, the new way to measure seems obviously better and makes sense even if I cannot see a major improvement with the setup I'm using.

v4: - Merged close fix into IMC READ+WRITE rework patch - Add loop to reset imc_counters_config fds to -1 to be able know which need closing - Introduce perf_close_imc_mem_bw() to close fds - Open resctrl mem bw file (twice) beforehand to avoid opening it during the test - Remove MBM .mongrp setup - Remove mongrp from CMT test

v3: - Rename init functions to <testname>_init() - Replace for loops with READ+WRITE statements for clarity - Don't drop Return: entry from perf_open_imc_mem_bw() func comment - New patch: Fix closing of IMC fds in case of error - New patch: Make "bandwidth" consistent in comments & prints - New patch: Simplify mem bandwidth file code - Remove wrong comment - Changed grp_name check to return -1 on fail (internal sanity check)

v2: - Resolved conflicts with kselftest/next - Spaces -> tabs correction

Ilpo Järvinen (16): selftests/resctrl: Fix closing IMC fds on error and open-code R+W instead of loops selftests/resctrl: Calculate resctrl FS derived mem bw over sleep(1) only selftests/resctrl: Make "bandwidth" consistent in comments & prints selftests/resctrl: Consolidate get_domain_id() into resctrl_val() selftests/resctrl: Use correct type for pids selftests/resctrl: Cleanup bm_pid and ppid usage & limit scope selftests/resctrl: Rename measure_vals() to measure_mem_bw_vals() & document selftests/resctrl: Simplify mem bandwidth file code for MBA & MBM tests selftests/resctrl: Add ->measure() callback to resctrl_val_param selftests/resctrl: Add ->init() callback into resctrl_val_param selftests/resctrl: Simplify bandwidth report type handling selftests/resctrl: Make some strings passed to resctrlfs functions const selftests/resctrl: Convert ctrlgrp & mongrp to pointers selftests/resctrl: Remove mongrp from MBA test selftests/resctrl: Remove mongrp from CMT test selftests/resctrl: Remove test name comparing from write_bm_pid_to_resctrl()

tools/testing/selftests/resctrl/cache.c | 6 +- tools/testing/selftests/resctrl/cat_test.c | 5 +- tools/testing/selftests/resctrl/cmt_test.c | 22 +- tools/testing/selftests/resctrl/mba_test.c | 26 +- tools/testing/selftests/resctrl/mbm_test.c | 26 +- tools/testing/selftests/resctrl/resctrl.h | 49 ++- tools/testing/selftests/resctrl/resctrl_val.c | 362 ++++++++---------- tools/testing/selftests/resctrl/resctrlfs.c | 64 ++-- 8 files changed, 287 insertions(+), 273 deletions(-)