Add basic KUnit tests for the generic aspects of the lazy MMU mode: ensure that it appears active when it should, depending on how enable/disable and pause/resume pairs are nested.
Signed-off-by: Kevin Brodsky <[email protected]> --- mm/Kconfig | 12 ++++++ mm/Makefile | 1 + mm/tests/lazy_mmu_mode_kunit.c | 71 ++++++++++++++++++++++++++++++++++ 3 files changed, 84 insertions(+) create mode 100644 mm/tests/lazy_mmu_mode_kunit.c diff --git a/mm/Kconfig b/mm/Kconfig index 62073bd61544..ac48deb44884 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -1471,6 +1471,18 @@ config ARCH_HAS_LAZY_MMU_MODE MMU-related architectural state to be deferred until the mode is exited. See <linux/pgtable.h> for details. +config LAZY_MMU_MODE_KUNIT_TEST + tristate "KUnit tests for the lazy MMU mode" if !KUNIT_ALL_TESTS + depends on ARCH_HAS_LAZY_MMU_MODE + depends on KUNIT + default KUNIT_ALL_TESTS + help + Enable this option to check that the lazy MMU mode interface behaves + as expected. Only tests for the generic interface are included (not + architecture-specific behaviours). + + If unsure, say N. + source "mm/damon/Kconfig" endmenu diff --git a/mm/Makefile b/mm/Makefile index 2d0570a16e5b..9175f8cc6565 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -147,3 +147,4 @@ obj-$(CONFIG_SHRINKER_DEBUG) += shrinker_debug.o obj-$(CONFIG_EXECMEM) += execmem.o obj-$(CONFIG_TMPFS_QUOTA) += shmem_quota.o obj-$(CONFIG_PT_RECLAIM) += pt_reclaim.o +obj-$(CONFIG_LAZY_MMU_MODE_KUNIT_TEST) += tests/lazy_mmu_mode_kunit.o diff --git a/mm/tests/lazy_mmu_mode_kunit.c b/mm/tests/lazy_mmu_mode_kunit.c new file mode 100644 index 000000000000..2720eb995714 --- /dev/null +++ b/mm/tests/lazy_mmu_mode_kunit.c @@ -0,0 +1,71 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <kunit/test.h> +#include <linux/pgtable.h> + +static void expect_not_active(struct kunit *test) +{ + KUNIT_EXPECT_FALSE(test, is_lazy_mmu_mode_active()); +} + +static void expect_active(struct kunit *test) +{ + KUNIT_EXPECT_TRUE(test, is_lazy_mmu_mode_active()); +} + +static void lazy_mmu_mode_active(struct kunit *test) +{ + expect_not_active(test); + + lazy_mmu_mode_enable(); + expect_active(test); + + { + /* Nested section */ + lazy_mmu_mode_enable(); + expect_active(test); + + lazy_mmu_mode_disable(); + expect_active(test); + } + + { + /* Paused section */ + lazy_mmu_mode_pause(); + expect_not_active(test); + + { + /* No effect (paused) */ + lazy_mmu_mode_enable(); + expect_not_active(test); + + lazy_mmu_mode_disable(); + expect_not_active(test); + + lazy_mmu_mode_pause(); + expect_not_active(test); + + lazy_mmu_mode_resume(); + expect_not_active(test); + } + + lazy_mmu_mode_resume(); + expect_active(test); + } + + lazy_mmu_mode_disable(); + expect_not_active(test); +} + +static struct kunit_case lazy_mmu_mode_test_cases[] = { + KUNIT_CASE(lazy_mmu_mode_active), + {} +}; + +static struct kunit_suite lazy_mmu_mode_test_suite = { + .name = "lazy_mmu_mode", + .test_cases = lazy_mmu_mode_test_cases, +}; +kunit_test_suite(lazy_mmu_mode_test_suite); + +MODULE_DESCRIPTION("Tests for the lazy MMU mode"); +MODULE_LICENSE("GPL"); -- 2.51.2
