| Message ID | 20231017232152.2605440-5-nphamcs@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | workload-specific and memory pressure-driven zswap writeback | expand |
On Tue, Oct 17, 2023 at 4:21 PM Nhat Pham <nphamcs@gmail.com> wrote: > > From: Domenico Cerasuolo <cerasuolodomenico@gmail.com> > > The memcg-zswap self test is updated to adjust to the behavior change > implemented by commit 87730b165089 ("zswap: make shrinking memcg-aware"), > where zswap performs writeback for specific memcg. > > Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com> > Signed-off-by: Nhat Pham <nphamcs@gmail.com> /s/Signed-off/Acked This is Domenico's work :) I used the wrong tag here. Should be: Acked-by: Nhat Pham <nphamcs@gmail.com> > --- > tools/testing/selftests/cgroup/test_zswap.c | 74 ++++++++++++++------- > 1 file changed, 50 insertions(+), 24 deletions(-) > > diff --git a/tools/testing/selftests/cgroup/test_zswap.c b/tools/testing/selftests/cgroup/test_zswap.c > index 49def87a909b..11271fabeffc 100644 > --- a/tools/testing/selftests/cgroup/test_zswap.c > +++ b/tools/testing/selftests/cgroup/test_zswap.c > @@ -50,9 +50,9 @@ static int get_zswap_stored_pages(size_t *value) > return read_int("/sys/kernel/debug/zswap/stored_pages", value); > } > > -static int get_zswap_written_back_pages(size_t *value) > +static int get_cg_wb_count(const char *cg) > { > - return read_int("/sys/kernel/debug/zswap/written_back_pages", value); > + return cg_read_key_long(cg, "memory.stat", "zswap_wb"); > } > > static int allocate_bytes(const char *cgroup, void *arg) > @@ -68,45 +68,71 @@ static int allocate_bytes(const char *cgroup, void *arg) > return 0; > } > > +static char *setup_test_group_1M(const char *root, const char *name) > +{ > + char *group_name = cg_name(root, name); > + > + if (!group_name) > + return NULL; > + if (cg_create(group_name)) > + goto fail; > + if (cg_write(group_name, "memory.max", "1M")) { > + cg_destroy(group_name); > + goto fail; > + } > + return group_name; > +fail: > + free(group_name); > + return NULL; > +} > + > /* > * When trying to store a memcg page in zswap, if the memcg hits its memory > - * limit in zswap, writeback should not be triggered. > - * > - * This was fixed with commit 0bdf0efa180a("zswap: do not shrink if cgroup may > - * not zswap"). Needs to be revised when a per memcg writeback mechanism is > - * implemented. > + * limit in zswap, writeback should affect only the zswapped pages of that > + * memcg. > */ > static int test_no_invasive_cgroup_shrink(const char *root) > { > - size_t written_back_before, written_back_after; > int ret = KSFT_FAIL; > - char *test_group; > + size_t control_allocation_size = MB(10); > + char *control_allocation, *wb_group = NULL, *control_group = NULL; > > /* Set up */ > - test_group = cg_name(root, "no_shrink_test"); > - if (!test_group) > - goto out; > - if (cg_create(test_group)) > + wb_group = setup_test_group_1M(root, "per_memcg_wb_test1"); > + if (!wb_group) > + return KSFT_FAIL; > + if (cg_write(wb_group, "memory.zswap.max", "10K")) > goto out; > - if (cg_write(test_group, "memory.max", "1M")) > + control_group = setup_test_group_1M(root, "per_memcg_wb_test2"); > + if (!control_group) > goto out; > - if (cg_write(test_group, "memory.zswap.max", "10K")) > + > + /* Push some test_group2 memory into zswap */ > + if (cg_enter_current(control_group)) > goto out; > - if (get_zswap_written_back_pages(&written_back_before)) > + control_allocation = malloc(control_allocation_size); > + for (int i = 0; i < control_allocation_size; i += 4095) > + control_allocation[i] = 'a'; > + if (cg_read_key_long(control_group, "memory.stat", "zswapped") < 1) > goto out; > > - /* Allocate 10x memory.max to push memory into zswap */ > - if (cg_run(test_group, allocate_bytes, (void *)MB(10))) > + /* Allocate 10x memory.max to push wb_group memory into zswap and trigger wb */ > + if (cg_run(wb_group, allocate_bytes, (void *)MB(10))) > goto out; > > - /* Verify that no writeback happened because of the memcg allocation */ > - if (get_zswap_written_back_pages(&written_back_after)) > - goto out; > - if (written_back_after == written_back_before) > + /* Verify that only zswapped memory from gwb_group has been written back */ > + if (get_cg_wb_count(wb_group) > 0 && get_cg_wb_count(control_group) == 0) > ret = KSFT_PASS; > out: > - cg_destroy(test_group); > - free(test_group); > + cg_enter_current(root); > + if (control_group) { > + cg_destroy(control_group); > + free(control_group); > + } > + cg_destroy(wb_group); > + free(wb_group); > + if (control_allocation) > + free(control_allocation); > return ret; > } > > -- > 2.34.1
On Tue, Oct 17, 2023 at 4:34 PM Nhat Pham <nphamcs@gmail.com> wrote: > > On Tue, Oct 17, 2023 at 4:21 PM Nhat Pham <nphamcs@gmail.com> wrote: > > > > From: Domenico Cerasuolo <cerasuolodomenico@gmail.com> > > > > The memcg-zswap self test is updated to adjust to the behavior change > > implemented by commit 87730b165089 ("zswap: make shrinking memcg-aware"), > > where zswap performs writeback for specific memcg. > > > > Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com> > > Signed-off-by: Nhat Pham <nphamcs@gmail.com> > > /s/Signed-off/Acked > This is Domenico's work :) I used the wrong tag here. Should be: > Acked-by: Nhat Pham <nphamcs@gmail.com> Please ignore this comment - it was pointed out to me that Signed-off is the appropriate tag here. > > > --- > > tools/testing/selftests/cgroup/test_zswap.c | 74 ++++++++++++++------- > > 1 file changed, 50 insertions(+), 24 deletions(-) > > > > diff --git a/tools/testing/selftests/cgroup/test_zswap.c b/tools/testing/selftests/cgroup/test_zswap.c > > index 49def87a909b..11271fabeffc 100644 > > --- a/tools/testing/selftests/cgroup/test_zswap.c > > +++ b/tools/testing/selftests/cgroup/test_zswap.c > > @@ -50,9 +50,9 @@ static int get_zswap_stored_pages(size_t *value) > > return read_int("/sys/kernel/debug/zswap/stored_pages", value); > > } > > > > -static int get_zswap_written_back_pages(size_t *value) > > +static int get_cg_wb_count(const char *cg) > > { > > - return read_int("/sys/kernel/debug/zswap/written_back_pages", value); > > + return cg_read_key_long(cg, "memory.stat", "zswap_wb"); > > } > > > > static int allocate_bytes(const char *cgroup, void *arg) > > @@ -68,45 +68,71 @@ static int allocate_bytes(const char *cgroup, void *arg) > > return 0; > > } > > > > +static char *setup_test_group_1M(const char *root, const char *name) > > +{ > > + char *group_name = cg_name(root, name); > > + > > + if (!group_name) > > + return NULL; > > + if (cg_create(group_name)) > > + goto fail; > > + if (cg_write(group_name, "memory.max", "1M")) { > > + cg_destroy(group_name); > > + goto fail; > > + } > > + return group_name; > > +fail: > > + free(group_name); > > + return NULL; > > +} > > + > > /* > > * When trying to store a memcg page in zswap, if the memcg hits its memory > > - * limit in zswap, writeback should not be triggered. > > - * > > - * This was fixed with commit 0bdf0efa180a("zswap: do not shrink if cgroup may > > - * not zswap"). Needs to be revised when a per memcg writeback mechanism is > > - * implemented. > > + * limit in zswap, writeback should affect only the zswapped pages of that > > + * memcg. > > */ > > static int test_no_invasive_cgroup_shrink(const char *root) > > { > > - size_t written_back_before, written_back_after; > > int ret = KSFT_FAIL; > > - char *test_group; > > + size_t control_allocation_size = MB(10); > > + char *control_allocation, *wb_group = NULL, *control_group = NULL; > > > > /* Set up */ > > - test_group = cg_name(root, "no_shrink_test"); > > - if (!test_group) > > - goto out; > > - if (cg_create(test_group)) > > + wb_group = setup_test_group_1M(root, "per_memcg_wb_test1"); > > + if (!wb_group) > > + return KSFT_FAIL; > > + if (cg_write(wb_group, "memory.zswap.max", "10K")) > > goto out; > > - if (cg_write(test_group, "memory.max", "1M")) > > + control_group = setup_test_group_1M(root, "per_memcg_wb_test2"); > > + if (!control_group) > > goto out; > > - if (cg_write(test_group, "memory.zswap.max", "10K")) > > + > > + /* Push some test_group2 memory into zswap */ > > + if (cg_enter_current(control_group)) > > goto out; > > - if (get_zswap_written_back_pages(&written_back_before)) > > + control_allocation = malloc(control_allocation_size); > > + for (int i = 0; i < control_allocation_size; i += 4095) > > + control_allocation[i] = 'a'; > > + if (cg_read_key_long(control_group, "memory.stat", "zswapped") < 1) > > goto out; > > > > - /* Allocate 10x memory.max to push memory into zswap */ > > - if (cg_run(test_group, allocate_bytes, (void *)MB(10))) > > + /* Allocate 10x memory.max to push wb_group memory into zswap and trigger wb */ > > + if (cg_run(wb_group, allocate_bytes, (void *)MB(10))) > > goto out; > > > > - /* Verify that no writeback happened because of the memcg allocation */ > > - if (get_zswap_written_back_pages(&written_back_after)) > > - goto out; > > - if (written_back_after == written_back_before) > > + /* Verify that only zswapped memory from gwb_group has been written back */ > > + if (get_cg_wb_count(wb_group) > 0 && get_cg_wb_count(control_group) == 0) > > ret = KSFT_PASS; > > out: > > - cg_destroy(test_group); > > - free(test_group); > > + cg_enter_current(root); > > + if (control_group) { > > + cg_destroy(control_group); > > + free(control_group); > > + } > > + cg_destroy(wb_group); > > + free(wb_group); > > + if (control_allocation) > > + free(control_allocation); > > return ret; > > } > > > > -- > > 2.34.1
diff --git a/tools/testing/selftests/cgroup/test_zswap.c b/tools/testing/selftests/cgroup/test_zswap.c index 49def87a909b..11271fabeffc 100644 --- a/tools/testing/selftests/cgroup/test_zswap.c +++ b/tools/testing/selftests/cgroup/test_zswap.c @@ -50,9 +50,9 @@ static int get_zswap_stored_pages(size_t *value) return read_int("/sys/kernel/debug/zswap/stored_pages", value); } -static int get_zswap_written_back_pages(size_t *value) +static int get_cg_wb_count(const char *cg) { - return read_int("/sys/kernel/debug/zswap/written_back_pages", value); + return cg_read_key_long(cg, "memory.stat", "zswap_wb"); } static int allocate_bytes(const char *cgroup, void *arg) @@ -68,45 +68,71 @@ static int allocate_bytes(const char *cgroup, void *arg) return 0; } +static char *setup_test_group_1M(const char *root, const char *name) +{ + char *group_name = cg_name(root, name); + + if (!group_name) + return NULL; + if (cg_create(group_name)) + goto fail; + if (cg_write(group_name, "memory.max", "1M")) { + cg_destroy(group_name); + goto fail; + } + return group_name; +fail: + free(group_name); + return NULL; +} + /* * When trying to store a memcg page in zswap, if the memcg hits its memory - * limit in zswap, writeback should not be triggered. - * - * This was fixed with commit 0bdf0efa180a("zswap: do not shrink if cgroup may - * not zswap"). Needs to be revised when a per memcg writeback mechanism is - * implemented. + * limit in zswap, writeback should affect only the zswapped pages of that + * memcg. */ static int test_no_invasive_cgroup_shrink(const char *root) { - size_t written_back_before, written_back_after; int ret = KSFT_FAIL; - char *test_group; + size_t control_allocation_size = MB(10); + char *control_allocation, *wb_group = NULL, *control_group = NULL; /* Set up */ - test_group = cg_name(root, "no_shrink_test"); - if (!test_group) - goto out; - if (cg_create(test_group)) + wb_group = setup_test_group_1M(root, "per_memcg_wb_test1"); + if (!wb_group) + return KSFT_FAIL; + if (cg_write(wb_group, "memory.zswap.max", "10K")) goto out; - if (cg_write(test_group, "memory.max", "1M")) + control_group = setup_test_group_1M(root, "per_memcg_wb_test2"); + if (!control_group) goto out; - if (cg_write(test_group, "memory.zswap.max", "10K")) + + /* Push some test_group2 memory into zswap */ + if (cg_enter_current(control_group)) goto out; - if (get_zswap_written_back_pages(&written_back_before)) + control_allocation = malloc(control_allocation_size); + for (int i = 0; i < control_allocation_size; i += 4095) + control_allocation[i] = 'a'; + if (cg_read_key_long(control_group, "memory.stat", "zswapped") < 1) goto out; - /* Allocate 10x memory.max to push memory into zswap */ - if (cg_run(test_group, allocate_bytes, (void *)MB(10))) + /* Allocate 10x memory.max to push wb_group memory into zswap and trigger wb */ + if (cg_run(wb_group, allocate_bytes, (void *)MB(10))) goto out; - /* Verify that no writeback happened because of the memcg allocation */ - if (get_zswap_written_back_pages(&written_back_after)) - goto out; - if (written_back_after == written_back_before) + /* Verify that only zswapped memory from gwb_group has been written back */ + if (get_cg_wb_count(wb_group) > 0 && get_cg_wb_count(control_group) == 0) ret = KSFT_PASS; out: - cg_destroy(test_group); - free(test_group); + cg_enter_current(root); + if (control_group) { + cg_destroy(control_group); + free(control_group); + } + cg_destroy(wb_group); + free(wb_group); + if (control_allocation) + free(control_allocation); return ret; }