en Copyright 2015 Java http://172.16.0.5:8080/history/linux-6.15/tools/testing/selftests/damon/access_memory.c#34ec4344 selftests/damon/access_memory: use user-defined region sizePatch series "selftests/damon: test DAMOS tried regions and{min,max}_nr_regions".This patch series fix a minor issue in a program for DAMON selftest, andimplement new functionality selftests for DAMOS tried regions and{min,max}_nr_regions. The test for max_nr_regions also test the recoveryfrom online tuning-caused limit violation, which was fixed by a previouspatch [1] titled "mm/damon/core: merge regions aggressively whenmax_nr_regions is unmet".The first patch fixes a minor problem in the articial memory accesspattern generator for tests. Following 3 patches (2-4) implement schemestried regions test. Then a couple of patches (5-6) implementing staticsetup based {min,max}_nr_regions functionality test follows. Final twopatches (7-8) implement dynamic max_nr_regions update test.[1] https://lore.kernel.org/20240624210650.53960C2BBFC@smtp.kernel.orgThis patch (of 8):'access_memory' is an artificial memory access pattern generator for DAMONtests. It creates and accesses memory regions that the user specified thenumber and size via the command line. However, real access part of theprogram ignores the user-specified size of each region. Instead, it usesa hard-coded value, 10 MiB. Fix it to use user-defined size.Note that all existing 'access_memory' users are setting the region sizeas 10 MiB. Hence no real problem has happened so far.Link: https://lkml.kernel.org/r/20240625180538.73134-1-sj@kernel.orgLink: https://lkml.kernel.org/r/20240625180538.73134-2-sj@kernel.orgFixes: b5906f5f7359 ("selftests/damon: add a test for update_schemes_tried_regions sysfs command")Signed-off-by: SeongJae Park <sj@kernel.org>Cc: Shuah Khan <shuah@kernel.org>Signed-off-by: Andrew Morton <akpm@linux-foundation.org> List of files: /linux-6.15/tools/testing/selftests/damon/access_memory.c Tue, 25 Jun 2024 18:05:31 +0000 SeongJae Park <sj@kernel.org> http://172.16.0.5:8080/history/linux-6.15/tools/testing/selftests/damon/access_memory.c#b5906f5f selftests/damon: add a test for update_schemes_tried_regions sysfs commandAdd a selftest for verifying the accuracy of DAMON's access monitoringfunctionality. The test starts a program of artificial access pattern,monitor the access pattern using DAMON, and check if DAMON finds expectedamount of hot data region (working set size) with only acceptable errorrate.Note that the acceptable error rate is set with only naive assumptions andsmall number of tests. Hence failures of the test may not always meanDAMON is broken. Rather than that, those could be a signal to betterunderstand the real accuracy level of DAMON in wider environments. Basedon further finding, we could optimize DAMON or adjust the expectation ofthe test.Link: https://lkml.kernel.org/r/20231212194810.54457-5-sj@kernel.orgSigned-off-by: SeongJae Park <sj@kernel.org>Cc: Shuah Khan <shuah@kernel.org>Signed-off-by: Andrew Morton <akpm@linux-foundation.org> List of files: /linux-6.15/tools/testing/selftests/damon/access_memory.c Tue, 12 Dec 2023 19:48:09 +0000 SeongJae Park <sj@kernel.org>