From: Suren Baghdasaryan Date: Sat, 19 Jul 2025 18:28:52 +0000 (-0700) Subject: selftests/proc: add verbose mode for /proc/pid/maps tearing tests X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=aadc099c480f98817849cd44585904402160fe21;p=thirdparty%2Flinux.git selftests/proc: add verbose mode for /proc/pid/maps tearing tests Add verbose mode to the /proc/pid/maps tearing tests to print debugging information. VERBOSE environment variable is used to enable it. Usage example: VERBOSE=1 ./proc-maps-race Link: https://lkml.kernel.org/r/20250719182854.3166724-5-surenb@google.com Signed-off-by: Suren Baghdasaryan Cc: Alexey Dobriyan Cc: Andrii Nakryiko Cc: Christian Brauner Cc: Christophe Leroy Cc: David Hildenbrand Cc: Jann Horn Cc: Jeongjun Park Cc: Johannes Weiner Cc: Josef Bacik Cc: Kalesh Singh Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Oscar Salvador Cc: "Paul E . McKenney" Cc: Peter Xu Cc: Ryan Roberts Cc: Shuah Khan Cc: Thomas Weißschuh Cc: T.J. Mercier Cc: Vlastimil Babka Cc: Ye Bin Signed-off-by: Andrew Morton --- diff --git a/tools/testing/selftests/proc/proc-maps-race.c b/tools/testing/selftests/proc/proc-maps-race.c index bc614a2d944aa..66773685a047b 100644 --- a/tools/testing/selftests/proc/proc-maps-race.c +++ b/tools/testing/selftests/proc/proc-maps-race.c @@ -77,6 +77,7 @@ FIXTURE(proc_maps_race) int shared_mem_size; int page_size; int vma_count; + bool verbose; int maps_fd; pid_t pid; }; @@ -188,12 +189,104 @@ static void stop_vma_modifier(struct vma_modifier_info *mod_info) signal_state(mod_info, SETUP_MODIFY_MAPS); } +static void print_first_lines(char *text, int nr) +{ + const char *end = text; + + while (nr && (end = strchr(end, '\n')) != NULL) { + nr--; + end++; + } + + if (end) { + int offs = end - text; + + text[offs] = '\0'; + printf(text); + text[offs] = '\n'; + printf("\n"); + } else { + printf(text); + } +} + +static void print_last_lines(char *text, int nr) +{ + const char *start = text + strlen(text); + + nr++; /* to ignore the last newline */ + while (nr) { + while (start > text && *start != '\n') + start--; + nr--; + start--; + } + printf(start); +} + +static void print_boundaries(const char *title, FIXTURE_DATA(proc_maps_race) *self) +{ + if (!self->verbose) + return; + + printf("%s", title); + /* Print 3 boundary lines from each page */ + print_last_lines(self->page1.data, 3); + printf("-----------------page boundary-----------------\n"); + print_first_lines(self->page2.data, 3); +} + +static bool print_boundaries_on(bool condition, const char *title, + FIXTURE_DATA(proc_maps_race) *self) +{ + if (self->verbose && condition) + print_boundaries(title, self); + + return condition; +} + +static void report_test_start(const char *name, bool verbose) +{ + if (verbose) + printf("==== %s ====\n", name); +} + +static struct timespec print_ts; + +static void start_test_loop(struct timespec *ts, bool verbose) +{ + if (verbose) + print_ts.tv_sec = ts->tv_sec; +} + +static void end_test_iteration(struct timespec *ts, bool verbose) +{ + if (!verbose) + return; + + /* Update every second */ + if (print_ts.tv_sec == ts->tv_sec) + return; + + printf("."); + fflush(stdout); + print_ts.tv_sec = ts->tv_sec; +} + +static void end_test_loop(bool verbose) +{ + if (verbose) + printf("\n"); +} + static bool capture_mod_pattern(FIXTURE_DATA(proc_maps_race) *self, struct line_content *mod_last_line, struct line_content *mod_first_line, struct line_content *restored_last_line, struct line_content *restored_first_line) { + print_boundaries("Before modification", self); + signal_state(self->mod_info, SETUP_MODIFY_MAPS); wait_for_state(self->mod_info, SETUP_MAPS_MODIFIED); @@ -201,6 +294,8 @@ static bool capture_mod_pattern(FIXTURE_DATA(proc_maps_race) *self, if (!read_boundary_lines(self, mod_last_line, mod_first_line)) return false; + print_boundaries("After modification", self); + signal_state(self->mod_info, SETUP_RESTORE_MAPS); wait_for_state(self->mod_info, SETUP_MAPS_RESTORED); @@ -208,6 +303,8 @@ static bool capture_mod_pattern(FIXTURE_DATA(proc_maps_race) *self, if (!read_boundary_lines(self, restored_last_line, restored_first_line)) return false; + print_boundaries("After restore", self); + if (!self->mod_info->vma_mod_check(mod_last_line, mod_first_line, restored_last_line, restored_first_line)) return false; @@ -295,6 +392,7 @@ static inline bool check_remap_result(struct line_content *mod_last_line, FIXTURE_SETUP(proc_maps_race) { + const char *verbose = getenv("VERBOSE"); const char *duration = getenv("DURATION"); struct vma_modifier_info *mod_info; pthread_mutexattr_t mutex_attr; @@ -303,6 +401,7 @@ FIXTURE_SETUP(proc_maps_race) char fname[32]; self->page_size = (unsigned long)sysconf(_SC_PAGESIZE); + self->verbose = verbose && !strncmp(verbose, "1", 1); duration_sec = duration ? atol(duration) : 0; self->duration_sec = duration_sec ? duration_sec : 5UL; @@ -444,6 +543,7 @@ TEST_F(proc_maps_race, test_maps_tearing_from_split) mod_info->vma_restore = merge_vma; mod_info->vma_mod_check = check_split_result; + report_test_start("Tearing from split", self->verbose); ASSERT_TRUE(capture_mod_pattern(self, &split_last_line, &split_first_line, &restored_last_line, &restored_first_line)); @@ -455,6 +555,7 @@ TEST_F(proc_maps_race, test_maps_tearing_from_split) struct timespec start_ts, end_ts; clock_gettime(CLOCK_MONOTONIC_COARSE, &start_ts); + start_test_loop(&start_ts, self->verbose); do { bool last_line_changed; bool first_line_changed; @@ -472,12 +573,18 @@ TEST_F(proc_maps_race, test_maps_tearing_from_split) * In that case new first line will be the same as the * last restored line. */ - ASSERT_FALSE(strcmp(new_first_line.text, split_first_line.text) && - strcmp(new_first_line.text, restored_last_line.text)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_first_line.text, split_first_line.text) && + strcmp(new_first_line.text, restored_last_line.text), + "Split result invalid", self)); } else { /* The vmas should be consistent with merge results */ - ASSERT_FALSE(strcmp(new_last_line.text, restored_last_line.text)); - ASSERT_FALSE(strcmp(new_first_line.text, restored_first_line.text)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_last_line.text, restored_last_line.text), + "Merge result invalid", self)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_first_line.text, restored_first_line.text), + "Merge result invalid", self)); } /* * First and last lines should change in unison. If the last @@ -489,7 +596,9 @@ TEST_F(proc_maps_race, test_maps_tearing_from_split) ASSERT_EQ(last_line_changed, first_line_changed); clock_gettime(CLOCK_MONOTONIC_COARSE, &end_ts); + end_test_iteration(&end_ts, self->verbose); } while (end_ts.tv_sec - start_ts.tv_sec < self->duration_sec); + end_test_loop(self->verbose); /* Signal the modifyer thread to stop and wait until it exits */ signal_state(mod_info, TEST_DONE); @@ -513,6 +622,7 @@ TEST_F(proc_maps_race, test_maps_tearing_from_resize) mod_info->vma_restore = expand_vma; mod_info->vma_mod_check = check_shrink_result; + report_test_start("Tearing from resize", self->verbose); ASSERT_TRUE(capture_mod_pattern(self, &shrunk_last_line, &shrunk_first_line, &restored_last_line, &restored_first_line)); @@ -524,6 +634,7 @@ TEST_F(proc_maps_race, test_maps_tearing_from_resize) struct timespec start_ts, end_ts; clock_gettime(CLOCK_MONOTONIC_COARSE, &start_ts); + start_test_loop(&start_ts, self->verbose); do { ASSERT_TRUE(read_boundary_lines(self, &new_last_line, &new_first_line)); @@ -537,16 +648,24 @@ TEST_F(proc_maps_race, test_maps_tearing_from_resize) * again. In that case new first line will be the same * as the last restored line. */ - ASSERT_FALSE(strcmp(new_first_line.text, shrunk_first_line.text) && - strcmp(new_first_line.text, restored_last_line.text)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_first_line.text, shrunk_first_line.text) && + strcmp(new_first_line.text, restored_last_line.text), + "Shrink result invalid", self)); } else { /* The vmas should be consistent with the original/resored state */ - ASSERT_FALSE(strcmp(new_last_line.text, restored_last_line.text)); - ASSERT_FALSE(strcmp(new_first_line.text, restored_first_line.text)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_last_line.text, restored_last_line.text), + "Expand result invalid", self)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_first_line.text, restored_first_line.text), + "Expand result invalid", self)); } clock_gettime(CLOCK_MONOTONIC_COARSE, &end_ts); + end_test_iteration(&end_ts, self->verbose); } while (end_ts.tv_sec - start_ts.tv_sec < self->duration_sec); + end_test_loop(self->verbose); /* Signal the modifyer thread to stop and wait until it exits */ signal_state(mod_info, TEST_DONE); @@ -570,6 +689,7 @@ TEST_F(proc_maps_race, test_maps_tearing_from_remap) mod_info->vma_restore = patch_vma; mod_info->vma_mod_check = check_remap_result; + report_test_start("Tearing from remap", self->verbose); ASSERT_TRUE(capture_mod_pattern(self, &remapped_last_line, &remapped_first_line, &restored_last_line, &restored_first_line)); @@ -581,6 +701,7 @@ TEST_F(proc_maps_race, test_maps_tearing_from_remap) struct timespec start_ts, end_ts; clock_gettime(CLOCK_MONOTONIC_COARSE, &start_ts); + start_test_loop(&start_ts, self->verbose); do { ASSERT_TRUE(read_boundary_lines(self, &new_last_line, &new_first_line)); @@ -594,16 +715,24 @@ TEST_F(proc_maps_race, test_maps_tearing_from_remap) * again. In that case new first line will be the same * as the last restored line. */ - ASSERT_FALSE(strcmp(new_first_line.text, remapped_first_line.text) && - strcmp(new_first_line.text, restored_last_line.text)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_first_line.text, remapped_first_line.text) && + strcmp(new_first_line.text, restored_last_line.text), + "Remap result invalid", self)); } else { /* The vmas should be consistent with the original/resored state */ - ASSERT_FALSE(strcmp(new_last_line.text, restored_last_line.text)); - ASSERT_FALSE(strcmp(new_first_line.text, restored_first_line.text)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_last_line.text, restored_last_line.text), + "Remap restore result invalid", self)); + ASSERT_FALSE(print_boundaries_on( + strcmp(new_first_line.text, restored_first_line.text), + "Remap restore result invalid", self)); } clock_gettime(CLOCK_MONOTONIC_COARSE, &end_ts); + end_test_iteration(&end_ts, self->verbose); } while (end_ts.tv_sec - start_ts.tv_sec < self->duration_sec); + end_test_loop(self->verbose); /* Signal the modifyer thread to stop and wait until it exits */ signal_state(mod_info, TEST_DONE);