March 2024 - Linux-kselftest-mirror

[PATCH] selftests: x86: conform test to TAP format output

by Muhammad Usama Anjum

Conform the layout, informational and status messages to TAP. No functional change is intended other than the layout of output messages. Signed-off-by: Muhammad Usama Anjum <usama.anjum(a)collabora.com> --- tools/testing/selftests/x86/vdso_restorer.c | 29 +++++++++------------ 1 file changed, 12 insertions(+), 17 deletions(-) diff --git a/tools/testing/selftests/x86/vdso_restorer.c b/tools/testing/selftests/x86/vdso_restorer.c index fe99f24341554..f621167424a9c 100644 --- a/tools/testing/selftests/x86/vdso_restorer.c +++ b/tools/testing/selftests/x86/vdso_restorer.c @@ -21,6 +21,7 @@ #include <unistd.h> #include <syscall.h> #include <sys/syscall.h> +#include "../kselftest.h" /* Open-code this -- the headers are too messy to easily use them. */ struct real_sigaction { @@ -44,17 +45,19 @@ static void handler_without_siginfo(int sig) int main() { - int nerrs = 0; struct real_sigaction sa; + ksft_print_header(); + ksft_set_plan(2); + void *vdso = dlopen("linux-vdso.so.1", RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD); if (!vdso) vdso = dlopen("linux-gate.so.1", RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD); if (!vdso) { - printf("[SKIP]\tFailed to find vDSO. Tests are not expected to work.\n"); - return 0; + ksft_print_msg("[SKIP]\tFailed to find vDSO. Tests are not expected to work.\n"); + return KSFT_SKIP; } memset(&sa, 0, sizeof(sa)); @@ -62,21 +65,16 @@ int main() sa.flags = SA_SIGINFO; sa.restorer = NULL; /* request kernel-provided restorer */ - printf("[RUN]\tRaise a signal, SA_SIGINFO, sa.restorer == NULL\n"); + ksft_print_msg("Raise a signal, SA_SIGINFO, sa.restorer == NULL\n"); if (syscall(SYS_rt_sigaction, SIGUSR1, &sa, NULL, 8) != 0) err(1, "raw rt_sigaction syscall"); raise(SIGUSR1); - if (handler_called) { - printf("[OK]\tSA_SIGINFO handler returned successfully\n"); - } else { - printf("[FAIL]\tSA_SIGINFO handler was not called\n"); - nerrs++; - } + ksft_test_result(handler_called, "SA_SIGINFO handler returned\n"); - printf("[RUN]\tRaise a signal, !SA_SIGINFO, sa.restorer == NULL\n"); + ksft_print_msg("Raise a signal, !SA_SIGINFO, sa.restorer == NULL\n"); sa.flags = 0; sa.handler = handler_without_siginfo; @@ -86,10 +84,7 @@ int main() raise(SIGUSR1); - if (handler_called) { - printf("[OK]\t!SA_SIGINFO handler returned successfully\n"); - } else { - printf("[FAIL]\t!SA_SIGINFO handler was not called\n"); - nerrs++; - } + ksft_test_result(handler_called, "SA_SIGINFO handler returned\n"); + + ksft_finished(); } -- 2.39.2

2 weeks, 3 days

1
4
0 0

[PATCH] selftests: mm: restore settings from only parent process

by Muhammad Usama Anjum

The atexit() is called from parent process as well as forked processes. Hence the child restores the settings at exit while the parent is still executing. Fix this by checking pid of atexit() calling process and only restore THP number from parent process. Fixes: c23ea61726d5 ("selftests/mm: protection_keys: save/restore nr_hugepages settings") Tested-by: Joey Gouly <joey.gouly(a)arm.com> Signed-off-by: Muhammad Usama Anjum <usama.anjum(a)collabora.com> --- tools/testing/selftests/mm/protection_keys.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/mm/protection_keys.c b/tools/testing/selftests/mm/protection_keys.c index f822ae31af22e..374a308174d2b 100644 --- a/tools/testing/selftests/mm/protection_keys.c +++ b/tools/testing/selftests/mm/protection_keys.c @@ -1745,9 +1745,12 @@ void pkey_setup_shadow(void) shadow_pkey_reg = __read_pkey_reg(); } +pid_t parent_pid; + void restore_settings_atexit(void) { - cat_into_file(buf, "/proc/sys/vm/nr_hugepages"); + if (parent_pid == getpid()) + cat_into_file(buf, "/proc/sys/vm/nr_hugepages"); } void save_settings(void) @@ -1773,6 +1776,7 @@ void save_settings(void) exit(__LINE__); } + parent_pid = getpid(); atexit(restore_settings_atexit); close(fd); } -- 2.39.2

2 weeks, 6 days

2
2
0 0

[PATCH] selftests: iommu: add config needed for iommufd_fail_nth

by Muhammad Usama Anjum

Add FAULT_INJECTION_DEBUG_FS and FAILSLAB configurations which are needed by iommufd_fail_nth test. Signed-off-by: Muhammad Usama Anjum <usama.anjum(a)collabora.com> --- While building and running these tests on x86, defconfig had these configs enabled. But ARM64's defconfig doesn't enable these configs. Hence the config options are being added explicitly in this patch. --- tools/testing/selftests/iommu/config | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/iommu/config b/tools/testing/selftests/iommu/config index 110d73917615d..02a2a1b267c1e 100644 --- a/tools/testing/selftests/iommu/config +++ b/tools/testing/selftests/iommu/config @@ -1,3 +1,5 @@ CONFIG_IOMMUFD=y +CONFIG_FAULT_INJECTION_DEBUG_FS=y CONFIG_FAULT_INJECTION=y CONFIG_IOMMUFD_TEST=y +CONFIG_FAILSLAB=y -- 2.39.2

3 weeks, 2 days

3
17
0 0

[PATCH v6] selftests/dmabuf-heap: conform test to TAP format output

by Muhammad Usama Anjum

Conform the layout, informational and status messages to TAP. No functional change is intended other than the layout of output messages. Improve the TAP messages as well. Reviewed-by: T.J. Mercier <tjmercier(a)google.com> Signed-off-by: Muhammad Usama Anjum <usama.anjum(a)collabora.com> --- Changes since v5: - Make the TAP messages more by adding more informat Changes since v4: - close fds correctly with code changes added in v3 Chanages since v3: - abort test-case instead of exiting if heap/mem allocation fails - Correct test_alloc_zeroed() test case in case of failure Changes since v2: - Minor improvements in test_alloc_zeroed() results Changes since v1: - Update some more error handling code --- .../selftests/dmabuf-heaps/dmabuf-heap.c | 247 +++++++----------- 1 file changed, 101 insertions(+), 146 deletions(-) diff --git a/tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c b/tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c index 890a8236a8ba7..5f541522364fb 100644 --- a/tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c +++ b/tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c @@ -15,6 +15,7 @@ #include <linux/dma-buf.h> #include <linux/dma-heap.h> #include <drm/drm.h> +#include "../kselftest.h" #define DEVPATH "/dev/dma_heap" @@ -90,14 +91,13 @@ static int dmabuf_heap_open(char *name) char buf[256]; ret = snprintf(buf, 256, "%s/%s", DEVPATH, name); - if (ret < 0) { - printf("snprintf failed!\n"); - return ret; - } + if (ret < 0) + ksft_exit_fail_msg("snprintf failed! %d\n", ret); fd = open(buf, O_RDWR); if (fd < 0) - printf("open %s failed!\n", buf); + ksft_exit_fail_msg("open %s failed: %s\n", buf, strerror(errno)); + return fd; } @@ -140,7 +140,7 @@ static int dmabuf_sync(int fd, int start_stop) #define ONE_MEG (1024 * 1024) -static int test_alloc_and_import(char *heap_name) +static void test_alloc_and_import(char *heap_name) { int heap_fd = -1, dmabuf_fd = -1, importer_fd = -1; uint32_t handle = 0; @@ -148,27 +148,19 @@ static int test_alloc_and_import(char *heap_name) int ret; heap_fd = dmabuf_heap_open(heap_name); - if (heap_fd < 0) - return -1; - printf(" Testing allocation and importing: "); + ksft_print_msg("Testing allocation and importing:\n"); ret = dmabuf_heap_alloc(heap_fd, ONE_MEG, 0, &dmabuf_fd); if (ret) { - printf("FAIL (Allocation Failed!)\n"); - ret = -1; - goto out; + ksft_test_result_fail("FAIL (Allocation Failed!) %d\n", ret); + return; } + /* mmap and write a simple pattern */ - p = mmap(NULL, - ONE_MEG, - PROT_READ | PROT_WRITE, - MAP_SHARED, - dmabuf_fd, - 0); + p = mmap(NULL, ONE_MEG, PROT_READ | PROT_WRITE, MAP_SHARED, dmabuf_fd, 0); if (p == MAP_FAILED) { - printf("FAIL (mmap() failed)\n"); - ret = -1; - goto out; + ksft_test_result_fail("FAIL (mmap() failed): %s\n", strerror(errno)); + goto close_and_return; } dmabuf_sync(dmabuf_fd, DMA_BUF_SYNC_START); @@ -178,71 +170,64 @@ static int test_alloc_and_import(char *heap_name) importer_fd = open_vgem(); if (importer_fd < 0) { - ret = importer_fd; - printf("(Could not open vgem - skipping): "); + ksft_test_result_skip("Could not open vgem %d\n", importer_fd); } else { ret = import_vgem_fd(importer_fd, dmabuf_fd, &handle); - if (ret < 0) { - printf("FAIL (Failed to import buffer)\n"); - goto out; - } + ksft_test_result(ret >= 0, "Import buffer %d\n", ret); } ret = dmabuf_sync(dmabuf_fd, DMA_BUF_SYNC_START); if (ret < 0) { - printf("FAIL (DMA_BUF_SYNC_START failed!)\n"); + ksft_print_msg("FAIL (DMA_BUF_SYNC_START failed!) %d\n", ret); goto out; } memset(p, 0xff, ONE_MEG); ret = dmabuf_sync(dmabuf_fd, DMA_BUF_SYNC_END); if (ret < 0) { - printf("FAIL (DMA_BUF_SYNC_END failed!)\n"); + ksft_print_msg("FAIL (DMA_BUF_SYNC_END failed!) %d\n", ret); goto out; } close_handle(importer_fd, handle); - ret = 0; - printf(" OK\n"); + ksft_test_result_pass("%s dmabuf sync succeeded\n", __func__); + return; + out: - if (p) - munmap(p, ONE_MEG); - if (importer_fd >= 0) - close(importer_fd); - if (dmabuf_fd >= 0) - close(dmabuf_fd); - if (heap_fd >= 0) - close(heap_fd); + ksft_test_result_fail("%s dmabuf sync failed\n", __func__); + munmap(p, ONE_MEG); + close(importer_fd); - return ret; +close_and_return: + close(dmabuf_fd); + close(heap_fd); } -static int test_alloc_zeroed(char *heap_name, size_t size) +static void test_alloc_zeroed(char *heap_name, size_t size) { int heap_fd = -1, dmabuf_fd[32]; - int i, j, ret; + int i, j, k, ret; void *p = NULL; char *c; - printf(" Testing alloced %ldk buffers are zeroed: ", size / 1024); + ksft_print_msg("Testing alloced %ldk buffers are zeroed:\n", size / 1024); heap_fd = dmabuf_heap_open(heap_name); - if (heap_fd < 0) - return -1; /* Allocate and fill a bunch of buffers */ for (i = 0; i < 32; i++) { ret = dmabuf_heap_alloc(heap_fd, size, 0, &dmabuf_fd[i]); - if (ret < 0) { - printf("FAIL (Allocation (%i) failed)\n", i); - goto out; + if (ret) { + ksft_test_result_fail("FAIL (Allocation (%i) failed) %d\n", i, ret); + goto close_and_return; } + /* mmap and fill with simple pattern */ p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, dmabuf_fd[i], 0); if (p == MAP_FAILED) { - printf("FAIL (mmap() failed!)\n"); - ret = -1; - goto out; + ksft_test_result_fail("FAIL (mmap() failed!): %s\n", strerror(errno)); + goto close_and_return; } + dmabuf_sync(dmabuf_fd[i], DMA_BUF_SYNC_START); memset(p, 0xff, size); dmabuf_sync(dmabuf_fd[i], DMA_BUF_SYNC_END); @@ -251,48 +236,47 @@ static int test_alloc_zeroed(char *heap_name, size_t size) /* close them all */ for (i = 0; i < 32; i++) close(dmabuf_fd[i]); + ksft_test_result_pass("Allocate and fill a bunch of buffers\n"); /* Allocate and validate all buffers are zeroed */ for (i = 0; i < 32; i++) { ret = dmabuf_heap_alloc(heap_fd, size, 0, &dmabuf_fd[i]); if (ret < 0) { - printf("FAIL (Allocation (%i) failed)\n", i); - goto out; + ksft_test_result_fail("FAIL (Allocation (%i) failed) %d\n", i, ret); + goto close_and_return; } /* mmap and validate everything is zero */ p = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, dmabuf_fd[i], 0); if (p == MAP_FAILED) { - printf("FAIL (mmap() failed!)\n"); - ret = -1; - goto out; + ksft_test_result_fail("FAIL (mmap() failed!): %s\n", strerror(errno)); + goto close_and_return; } + dmabuf_sync(dmabuf_fd[i], DMA_BUF_SYNC_START); c = (char *)p; for (j = 0; j < size; j++) { if (c[j] != 0) { - printf("FAIL (Allocated buffer not zeroed @ %i)\n", j); - break; + ksft_print_msg("FAIL (Allocated buffer not zeroed @ %i)\n", j); + dmabuf_sync(dmabuf_fd[i], DMA_BUF_SYNC_END); + munmap(p, size); + goto out; } } dmabuf_sync(dmabuf_fd[i], DMA_BUF_SYNC_END); munmap(p, size); } - /* close them all */ - for (i = 0; i < 32; i++) - close(dmabuf_fd[i]); - - close(heap_fd); - printf("OK\n"); - return 0; out: - while (i > 0) { - close(dmabuf_fd[i]); - i--; - } + ksft_test_result(i == 32, "Allocate and validate all buffers are zeroed\n"); + +close_and_return: + /* close them all */ + for (k = 0; k < i; k++) + close(dmabuf_fd[k]); + close(heap_fd); - return ret; + return; } /* Test the ioctl version compatibility w/ a smaller structure then expected */ @@ -360,126 +344,97 @@ static int dmabuf_heap_alloc_newer(int fd, size_t len, unsigned int flags, return ret; } -static int test_alloc_compat(char *heap_name) +static void test_alloc_compat(char *heap_name) { - int heap_fd = -1, dmabuf_fd = -1; - int ret; + int ret, heap_fd = -1, dmabuf_fd = -1; heap_fd = dmabuf_heap_open(heap_name); - if (heap_fd < 0) - return -1; - printf(" Testing (theoretical)older alloc compat: "); + ksft_print_msg("Testing (theoretical) older alloc compat:\n"); ret = dmabuf_heap_alloc_older(heap_fd, ONE_MEG, 0, &dmabuf_fd); - if (ret) { - printf("FAIL (Older compat allocation failed!)\n"); - ret = -1; - goto out; - } - close(dmabuf_fd); - printf("OK\n"); + if (dmabuf_fd >= 0) + close(dmabuf_fd); + ksft_test_result(!ret, "dmabuf_heap_alloc_older\n"); - printf(" Testing (theoretical)newer alloc compat: "); + ksft_print_msg("Testing (theoretical) newer alloc compat:\n"); ret = dmabuf_heap_alloc_newer(heap_fd, ONE_MEG, 0, &dmabuf_fd); - if (ret) { - printf("FAIL (Newer compat allocation failed!)\n"); - ret = -1; - goto out; - } - printf("OK\n"); -out: if (dmabuf_fd >= 0) close(dmabuf_fd); - if (heap_fd >= 0) - close(heap_fd); + ksft_test_result(!ret, "dmabuf_heap_alloc_newer\n"); - return ret; + close(heap_fd); } -static int test_alloc_errors(char *heap_name) +static void test_alloc_errors(char *heap_name) { int heap_fd = -1, dmabuf_fd = -1; int ret; heap_fd = dmabuf_heap_open(heap_name); - if (heap_fd < 0) - return -1; - printf(" Testing expected error cases: "); + ksft_print_msg("Testing expected error cases:\n"); ret = dmabuf_heap_alloc(0, ONE_MEG, 0x111111, &dmabuf_fd); - if (!ret) { - printf("FAIL (Did not see expected error (invalid fd)!)\n"); - ret = -1; - goto out; - } + ksft_test_result(ret, "Error expected on invalid fd %d\n", ret); ret = dmabuf_heap_alloc(heap_fd, ONE_MEG, 0x111111, &dmabuf_fd); - if (!ret) { - printf("FAIL (Did not see expected error (invalid heap flags)!)\n"); - ret = -1; - goto out; - } + ksft_test_result(ret, "Error expected on invalid heap flags %d\n", ret); ret = dmabuf_heap_alloc_fdflags(heap_fd, ONE_MEG, ~(O_RDWR | O_CLOEXEC), 0, &dmabuf_fd); - if (!ret) { - printf("FAIL (Did not see expected error (invalid fd flags)!)\n"); - ret = -1; - goto out; - } + ksft_test_result(ret, "Error expected on invalid heap flags %d\n", ret); - printf("OK\n"); - ret = 0; -out: if (dmabuf_fd >= 0) close(dmabuf_fd); - if (heap_fd >= 0) - close(heap_fd); + close(heap_fd); +} - return ret; +static int numer_of_heaps(void) +{ + DIR *d = opendir(DEVPATH); + struct dirent *dir; + int heaps = 0; + + while ((dir = readdir(d))) { + if (!strncmp(dir->d_name, ".", 2)) + continue; + if (!strncmp(dir->d_name, "..", 3)) + continue; + heaps++; + } + + return heaps; } int main(void) { - DIR *d; struct dirent *dir; - int ret = -1; + DIR *d; + + ksft_print_header(); d = opendir(DEVPATH); if (!d) { - printf("No %s directory?\n", DEVPATH); - return -1; + ksft_print_msg("No %s directory?\n", DEVPATH); + return KSFT_SKIP; } - while ((dir = readdir(d)) != NULL) { + ksft_set_plan(11 * numer_of_heaps()); + + while ((dir = readdir(d))) { if (!strncmp(dir->d_name, ".", 2)) continue; if (!strncmp(dir->d_name, "..", 3)) continue; - printf("Testing heap: %s\n", dir->d_name); - printf("=======================================\n"); - ret = test_alloc_and_import(dir->d_name); - if (ret) - break; - - ret = test_alloc_zeroed(dir->d_name, 4 * 1024); - if (ret) - break; - - ret = test_alloc_zeroed(dir->d_name, ONE_MEG); - if (ret) - break; - - ret = test_alloc_compat(dir->d_name); - if (ret) - break; - - ret = test_alloc_errors(dir->d_name); - if (ret) - break; + ksft_print_msg("Testing heap: %s\n", dir->d_name); + ksft_print_msg("=======================================\n"); + test_alloc_and_import(dir->d_name); + test_alloc_zeroed(dir->d_name, 4 * 1024); + test_alloc_zeroed(dir->d_name, ONE_MEG); + test_alloc_compat(dir->d_name); + test_alloc_errors(dir->d_name); } closedir(d); - return ret; + ksft_finished(); } -- 2.39.2

3 weeks, 3 days

1
3
0 0

[PATCH v6 1/2] posix-timers: Prefer delivery of signals to the current thread

by Marco Elver

From: Dmitry Vyukov <dvyukov(a)google.com> POSIX timers using the CLOCK_PROCESS_CPUTIME_ID clock prefer the main thread of a thread group for signal delivery. However, this has a significant downside: it requires waking up a potentially idle thread. Instead, prefer to deliver signals to the current thread (in the same thread group) if SIGEV_THREAD_ID is not set by the user. This does not change guaranteed semantics, since POSIX process CPU time timers have never guaranteed that signal delivery is to a specific thread (without SIGEV_THREAD_ID set). The effect is that we no longer wake up potentially idle threads, and the kernel is no longer biased towards delivering the timer signal to any particular thread (which better distributes the timer signals esp. when multiple timers fire concurrently). Signed-off-by: Dmitry Vyukov <dvyukov(a)google.com> Suggested-by: Oleg Nesterov <oleg(a)redhat.com> Reviewed-by: Oleg Nesterov <oleg(a)redhat.com> Signed-off-by: Marco Elver <elver(a)google.com> --- v6: - Split test from this patch. - Update wording on what this patch aims to improve. v5: - Rebased onto v6.2. v4: - Restructured checks in send_sigqueue() as suggested. v3: - Switched to the completely different implementation (much simpler) based on the Oleg's idea. RFC v2: - Added additional Cc as Thomas asked. --- kernel/signal.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) diff --git a/kernel/signal.c b/kernel/signal.c index 8cb28f1df294..605445fa27d4 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1003,8 +1003,7 @@ static void complete_signal(int sig, struct task_struct *p, enum pid_type type) /* * Now find a thread we can wake up to take the signal off the queue. * - * If the main thread wants the signal, it gets first crack. - * Probably the least surprising to the average bear. + * Try the suggested task first (may or may not be the main thread). */ if (wants_signal(sig, p)) t = p; @@ -1970,8 +1969,23 @@ int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type) ret = -1; rcu_read_lock(); + /* + * This function is used by POSIX timers to deliver a timer signal. + * Where type is PIDTYPE_PID (such as for timers with SIGEV_THREAD_ID + * set), the signal must be delivered to the specific thread (queues + * into t->pending). + * + * Where type is not PIDTYPE_PID, signals must just be delivered to the + * current process. In this case, prefer to deliver to current if it is + * in the same thread group as the target, as it avoids unnecessarily + * waking up a potentially idle task. + */ t = pid_task(pid, type); - if (!t || !likely(lock_task_sighand(t, &flags))) + if (!t) + goto ret; + if (type != PIDTYPE_PID && same_thread_group(t, current)) + t = current; + if (!likely(lock_task_sighand(t, &flags))) goto ret; ret = 1; /* the signal is ignored */ @@ -1993,6 +2007,11 @@ int send_sigqueue(struct sigqueue *q, struct pid *pid, enum pid_type type) q->info.si_overrun = 0; signalfd_notify(t, sig); + /* + * If the type is not PIDTYPE_PID, we just use shared_pending, which + * won't guarantee that the specified task will receive the signal, but + * is sufficient if t==current in the common case. + */ pending = (type != PIDTYPE_PID) ? &t->signal->shared_pending : &t->pending; list_add_tail(&q->list, &pending->list); sigaddset(&pending->signal, sig); -- 2.40.0.rc1.284.g88254d51c5-goog

3 weeks, 4 days

9
50
0 0

[PATCH v3] selftests/ftrace: traceonoff_triggers: strip off names

by Yipeng Zou

The func_traceonoff_triggers.tc sometimes goes to fail on my board, Kunpeng-920. [root@localhost]# ./ftracetest ./test.d/ftrace/func_traceonoff_triggers.tc -l fail.log === Ftrace unit tests === [1] ftrace - test for function traceon/off triggers [FAIL] [2] (instance) ftrace - test for function traceon/off triggers [UNSUPPORTED] I look up the log, and it shows that the md5sum is different between csum1 and csum2. ++ cnt=611 ++ sleep .1 +++ cnt_trace +++ grep -v '^#' trace +++ wc -l ++ cnt2=611 ++ '[' 611 -ne 611 ']' +++ cat tracing_on ++ on=0 ++ '[' 0 '!=' 0 ']' +++ md5sum trace ++ csum1='76896aa74362fff66a6a5f3cf8a8a500 trace' ++ sleep .1 +++ md5sum trace ++ csum2='ee8625a21c058818fc26e45c1ed3f6de trace' ++ '[' '76896aa74362fff66a6a5f3cf8a8a500 trace' '!=' 'ee8625a21c058818fc26e45c1ed3f6de trace' ']' ++ fail 'Tracing file is still changing' ++ echo Tracing file is still changing Tracing file is still changing ++ exit_fail ++ exit 1 So I directly dump the trace file before md5sum, the diff shows that: [root@localhost]# diff trace_1.log trace_2.log -y --suppress-common-lines dockerd-12285 [036] d.... 18385.510290: sched_stat | <...>-12285 [036] d.... 18385.510290: sched_stat dockerd-12285 [036] d.... 18385.510291: sched_swit | <...>-12285 [036] d.... 18385.510291: sched_swit <...>-740 [044] d.... 18385.602859: sched_stat | kworker/44:1-740 [044] d.... 18385.602859: sched_stat <...>-740 [044] d.... 18385.602860: sched_swit | kworker/44:1-740 [044] d.... 18385.602860: sched_swit And we can see that <...> filed be filled with names. We can strip off the names there to fix that. After strip off the names: kworker/u257:0-12 [019] d..2. 2528.758910: sched_stat | -12 [019] d..2. 2528.758910: sched_stat_runtime: comm=k kworker/u257:0-12 [019] d..2. 2528.758912: sched_swit | -12 [019] d..2. 2528.758912: sched_switch: prev_comm=kw <idle>-0 [000] d.s5. 2528.762318: sched_waki | -0 [000] d.s5. 2528.762318: sched_waking: comm=sshd pi <idle>-0 [037] dNh2. 2528.762326: sched_wake | -0 [037] dNh2. 2528.762326: sched_wakeup: comm=sshd pi <idle>-0 [037] d..2. 2528.762334: sched_swit | -0 [037] d..2. 2528.762334: sched_switch: prev_comm=sw Fixes: d87b29179aa0 ("selftests: ftrace: Use md5sum to take less time of checking logs") Suggested-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> Signed-off-by: Yipeng Zou <zouyipeng(a)huawei.com> Acked-by: Masami Hiramatsu (Google) <mhiramat(a)kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> --- .../ftrace/test.d/ftrace/func_traceonoff_triggers.tc | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc index aee22289536b..1b57771dbfdf 100644 --- a/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc +++ b/tools/testing/selftests/ftrace/test.d/ftrace/func_traceonoff_triggers.tc @@ -90,9 +90,10 @@ if [ $on != "0" ]; then fail "Tracing is not off" fi -csum1=`md5sum trace` +# Cannot rely on names being around as they are only cached, strip them +csum1=`cat trace | sed -e 's/^ *[^ ]*$-[0-9][0-9]*$/\1/' | md5sum` sleep $SLEEP_TIME -csum2=`md5sum trace` +csum2=`cat trace | sed -e 's/^ *[^ ]*$-[0-9][0-9]*$/\1/' | md5sum` if [ "$csum1" != "$csum2" ]; then fail "Tracing file is still changing" -- 2.34.1

3 weeks, 5 days

2
2
0 0

[PATCH] selftests/rseq: take large C-state exit latency into consideration

by Zide Chen

Currently, the migration worker delays 1-10 us, assuming that one KVM_RUN iteration only takes a few microseconds. But if C-state exit latencies are large enough, for example, hundreds or even thousands of microseconds on server CPUs, it may happen that it's not able to bring the target CPU out of C-state before the migration worker starts to migrate it to the next CPU. If the system workload is light, most CPUs could be at a certain level of C-state, and the vCPU thread may waste milliseconds before it can actually migrate to a new CPU. Thus, the tests may be inefficient in such systems, and in some cases it may fail the migration/KVM_RUN ratio sanity check. Since we are not able to turn off the cpuidle sub-system in run time, this patch creates an idle thread on every CPU to prevent them from entering C-states. Additionally, seems it's reasonable to randomize the length of usleep(), other than delay in a fixed pattern. Signed-off-by: Zide Chen <zide.chen(a)intel.com> --- tools/testing/selftests/kvm/rseq_test.c | 76 ++++++++++++++++++++++--- 1 file changed, 69 insertions(+), 7 deletions(-) diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c index 28f97fb52044..d6e8b851d29e 100644 --- a/tools/testing/selftests/kvm/rseq_test.c +++ b/tools/testing/selftests/kvm/rseq_test.c @@ -11,6 +11,7 @@ #include <syscall.h> #include <sys/ioctl.h> #include <sys/sysinfo.h> +#include <sys/resource.h> #include <asm/barrier.h> #include <linux/atomic.h> #include <linux/rseq.h> @@ -29,9 +30,10 @@ #define NR_TASK_MIGRATIONS 100000 static pthread_t migration_thread; +static pthread_t *idle_threads; static cpu_set_t possible_mask; -static int min_cpu, max_cpu; -static bool done; +static int min_cpu, max_cpu, nproc; +static volatile bool done; static atomic_t seq_cnt; @@ -150,7 +152,7 @@ static void *migration_worker(void *__rseq_tid) * Use usleep() for simplicity and to avoid unnecessary kernel * dependencies. */ - usleep((i % 10) + 1); + usleep((rand() % 10) + 1); } done = true; return NULL; @@ -158,7 +160,7 @@ static void *migration_worker(void *__rseq_tid) static void calc_min_max_cpu(void) { - int i, cnt, nproc; + int i, cnt; TEST_REQUIRE(CPU_COUNT(&possible_mask) >= 2); @@ -186,6 +188,61 @@ static void calc_min_max_cpu(void) "Only one usable CPU, task migration not possible"); } +static void *idle_thread_fn(void *__idle_cpu) +{ + int r, cpu = (int)(unsigned long)__idle_cpu; + cpu_set_t allowed_mask; + + CPU_ZERO(&allowed_mask); + CPU_SET(cpu, &allowed_mask); + + r = sched_setaffinity(0, sizeof(allowed_mask), &allowed_mask); + TEST_ASSERT(!r, "sched_setaffinity failed, errno = %d (%s)", + errno, strerror(errno)); + + /* lowest priority, trying to prevent it from entering C-states */ + r = setpriority(PRIO_PROCESS, 0, 19); + TEST_ASSERT(!r, "setpriority failed, errno = %d (%s)", + errno, strerror(errno)); + + while(!done); + + return NULL; +} + +static void spawn_threads(void) +{ + int cpu; + + /* Run a dummy thread on every CPU */ + for (cpu = min_cpu; cpu <= max_cpu; cpu++) { + if (!CPU_ISSET(cpu, &possible_mask)) + continue; + + pthread_create(&idle_threads[cpu], NULL, idle_thread_fn, + (void *)(unsigned long)cpu); + } + + pthread_create(&migration_thread, NULL, migration_worker, + (void *)(unsigned long)syscall(SYS_gettid)); +} + +static void join_threads(void) +{ + int cpu; + + pthread_join(migration_thread, NULL); + + for (cpu = min_cpu; cpu <= max_cpu; cpu++) { + if (!CPU_ISSET(cpu, &possible_mask)) + continue; + + pthread_join(idle_threads[cpu], NULL); + } + + free(idle_threads); +} + int main(int argc, char *argv[]) { int r, i, snapshot; @@ -199,6 +256,12 @@ int main(int argc, char *argv[]) calc_min_max_cpu(); + srand(time(NULL)); + + idle_threads = malloc(sizeof(pthread_t) * nproc); + TEST_ASSERT(idle_threads, "malloc failed, errno = %d (%s)", errno, + strerror(errno)); + r = rseq_register_current_thread(); TEST_ASSERT(!r, "rseq_register_current_thread failed, errno = %d (%s)", errno, strerror(errno)); @@ -210,8 +273,7 @@ int main(int argc, char *argv[]) */ vm = vm_create_with_one_vcpu(&vcpu, guest_code); - pthread_create(&migration_thread, NULL, migration_worker, - (void *)(unsigned long)syscall(SYS_gettid)); + spawn_threads(); for (i = 0; !done; i++) { vcpu_run(vcpu); @@ -258,7 +320,7 @@ int main(int argc, char *argv[]) TEST_ASSERT(i > (NR_TASK_MIGRATIONS / 2), "Only performed %d KVM_RUNs, task stalled too much?", i); - pthread_join(migration_thread, NULL); + join_threads(); kvm_vm_free(vm); -- 2.34.1

3 weeks, 5 days

3
4
0 0

[PATCH v3 00/30] NT synchronization primitive driver

by Elizabeth Figura

This patch series introduces a new char misc driver, /dev/ntsync, which is used to implement Windows NT synchronization primitives. == Background == The Wine project emulates the Windows API in user space. One particular part of that API, namely the NT synchronization primitives, have historically been implemented via RPC to a dedicated "kernel" process. However, more recent applications use these APIs more strenuously, and the overhead of RPC has become a bottleneck. The NT synchronization APIs are too complex to implement on top of existing primitives without sacrificing correctness. Certain operations, such as NtPulseEvent() or the "wait-for-all" mode of NtWaitForMultipleObjects(), require direct control over the underlying wait queue, and implementing a wait queue sufficiently robust for Wine in user space is not possible. This proposed driver, therefore, implements the problematic interfaces directly in the Linux kernel. This driver was presented at Linux Plumbers Conference 2023. For those further interested in the history of synchronization in Wine and past attempts to solve this problem in user space, a recording of the presentation can be viewed here: https://www.youtube.com/watch?v=NjU4nyWyhU8 == Performance == The gain in performance varies wildly depending on the application in question and the user's hardware. For some games NT synchronization is not a bottleneck and no change can be observed, but for others frame rate improvements of 50 to 150 percent are not atypical. The following table lists frame rate measurements from a variety of games on a variety of hardware, taken by users Dmitry Skvortsov, FuzzyQuils, OnMars, and myself: Game Upstream ntsync improvement =========================================================================== Anger Foot 69 99 43% Call of Juarez 99.8 224.1 125% Dirt 3 110.6 860.7 678% Forza Horizon 5 108 160 48% Lara Croft: Temple of Osiris 141 326 131% Metro 2033 164.4 199.2 21% Resident Evil 2 26 77 196% The Crew 26 51 96% Tiny Tina's Wonderlands 130 360 177% Total War Saga: Troy 109 146 34% =========================================================================== == Patches == The intended semantics of the patches are broadly intended to match those of the corresponding Windows functions. For those not already familiar with the Windows functions (or their undocumented behaviour), patch 31/31 provides a detailed specification, and individual patches also include a brief description of the API they are implementing. The patches making use of this driver in Wine can be retrieved or browsed here: https://repo.or.cz/wine/zf.git/shortlog/refs/heads/ntsync5 == Implementation == Some aspects of the implementation may deserve particular comment: * In the interest of performance, each object is governed only by a single spinlock. However, NTSYNC_IOC_WAIT_ALL requires that the state of multiple objects be changed as a single atomic operation. In order to achieve this, we first take a device-wide lock ("wait_all_lock") any time we are going to lock more than one object at a time. The maximum number of objects that can be used in a vectored wait, and therefore the maximum that can be locked simultaneously, is 64. This number is NT's own limit. The acquisition of multiple spinlocks will degrade performance. This is a conscious choice, however. Wait-for-all is known to be a very rare operation in practice, especially with counts that approach the maximum, and it is the intent of the ntsync driver to optimize wait-for-any at the expense of wait-for-all as much as possible. * NT mutexes are tied to their threads on an OS level, and the kernel includes builtin support for "robust" mutexes. In order to keep the ntsync driver self-contained and avoid touching more code than necessary, it does not hook into task exit nor use pids. Instead, the user space emulator is expected to manage thread IDs and pass them as an argument to any relevant functions; this is the "owner" field of ntsync_wait_args and ntsync_mutex_args. When the emulator detects that a thread dies, it should therefore call NTSYNC_IOC_MUTEX_KILL on any open mutexes. * ntsync is module-capable mostly because there was nothing preventing it, and because it aided development. It is not a hard requirement, though. == Previous versions == Changes from v2: * Check the result of fget() for NULL. * Squash patch 31 (introducing the NTSYNC_WAIT_REALTIME flag) into patch 4, per Arnd Bergmann. * Use atomic_try_cmpxchg() instead of atomic_cmpxchg(), per off-list review from Uros Bizjak. * Link to v2: https://lore.kernel.org/lkml/20240219223833.95710-1-zfigura@codeweavers.com/ * Link to v1: https://lore.kernel.org/lkml/20240214233645.9273-1-zfigura@codeweavers.com/ * Link to RFC v2: https://lore.kernel.org/lkml/20240131021356.10322-1-zfigura@codeweavers.com/ * Link to RFC v1: https://lore.kernel.org/lkml/20240124004028.16826-1-zfigura@codeweavers.com/ Elizabeth Figura (30): ntsync: Introduce the ntsync driver and character device. ntsync: Introduce NTSYNC_IOC_CREATE_SEM. ntsync: Introduce NTSYNC_IOC_SEM_POST. ntsync: Introduce NTSYNC_IOC_WAIT_ANY. ntsync: Introduce NTSYNC_IOC_WAIT_ALL. ntsync: Introduce NTSYNC_IOC_CREATE_MUTEX. ntsync: Introduce NTSYNC_IOC_MUTEX_UNLOCK. ntsync: Introduce NTSYNC_IOC_MUTEX_KILL. ntsync: Introduce NTSYNC_IOC_CREATE_EVENT. ntsync: Introduce NTSYNC_IOC_EVENT_SET. ntsync: Introduce NTSYNC_IOC_EVENT_RESET. ntsync: Introduce NTSYNC_IOC_EVENT_PULSE. ntsync: Introduce NTSYNC_IOC_SEM_READ. ntsync: Introduce NTSYNC_IOC_MUTEX_READ. ntsync: Introduce NTSYNC_IOC_EVENT_READ. ntsync: Introduce alertable waits. selftests: ntsync: Add some tests for semaphore state. selftests: ntsync: Add some tests for mutex state. selftests: ntsync: Add some tests for NTSYNC_IOC_WAIT_ANY. selftests: ntsync: Add some tests for NTSYNC_IOC_WAIT_ALL. selftests: ntsync: Add some tests for wakeup signaling with WINESYNC_IOC_WAIT_ANY. selftests: ntsync: Add some tests for wakeup signaling with WINESYNC_IOC_WAIT_ALL. selftests: ntsync: Add some tests for manual-reset event state. selftests: ntsync: Add some tests for auto-reset event state. selftests: ntsync: Add some tests for wakeup signaling with events. selftests: ntsync: Add tests for alertable waits. selftests: ntsync: Add some tests for wakeup signaling via alerts. selftests: ntsync: Add a stress test for contended waits. maintainers: Add an entry for ntsync. docs: ntsync: Add documentation for the ntsync uAPI. Documentation/userspace-api/index.rst | 1 + .../userspace-api/ioctl/ioctl-number.rst | 2 + Documentation/userspace-api/ntsync.rst | 399 +++++ MAINTAINERS | 9 + drivers/misc/Kconfig | 11 + drivers/misc/Makefile | 1 + drivers/misc/ntsync.c | 1166 ++++++++++++++ include/uapi/linux/ntsync.h | 62 + tools/testing/selftests/Makefile | 1 + .../testing/selftests/drivers/ntsync/Makefile | 8 + tools/testing/selftests/drivers/ntsync/config | 1 + .../testing/selftests/drivers/ntsync/ntsync.c | 1407 +++++++++++++++++ 12 files changed, 3068 insertions(+) create mode 100644 Documentation/userspace-api/ntsync.rst create mode 100644 drivers/misc/ntsync.c create mode 100644 include/uapi/linux/ntsync.h create mode 100644 tools/testing/selftests/drivers/ntsync/Makefile create mode 100644 tools/testing/selftests/drivers/ntsync/config create mode 100644 tools/testing/selftests/drivers/ntsync/ntsync.c base-commit: 4cece764965020c22cff7665b18a012006359095 -- 2.43.0

3 weeks, 6 days

4
36
0 0

[RFC PATCH bpf-next 0/3] bpf: freeze a task cgroup from bpf

by Djalal Harouni

This patch series adds support to freeze the task cgroup hierarchy that is on a default cgroup v2 without going through kernfs interface. For some cases we want to freeze the cgroup of a task based on some signals, doing so from bpf is better than user space which could be too late. Planned users of this feature are: tetragon and systemd when freezing a cgroup hierarchy that could be a K8s pod, container, system service or a user session. Patch 1: cgroup: add cgroup_freeze_no_kn() to freeze a cgroup from bpf Patch 2: bpf: add bpf_task_freeze_cgroup() to freeze the cgroup of a task Patch 3: selftests/bpf: add selftest for bpf_task_freeze_cgroup include/linux/cgroup.h | 2 ++ kernel/bpf/helpers.c | 31 ++++ kernel/cgroup/cgroup.c | 67 ++++++++ tools/testing/selftests/bpf/prog_tests/task_freeze_cgroup.c | 165 +++++++++++++++++++++ tools/testing/selftests/bpf/progs/test_task_freeze_cgroup.c | 110 ++++++++++++++ 5 files changed, 375 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/task_freeze_cgroup.c create mode 100644 tools/testing/selftests/bpf/progs/test_task_freeze_cgroup.c -- 2.34.1

4 weeks

5
22
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[PATCH v4 00/15] RISC-V SBI v2.0 PMU improvements and Perf sampling in KVM guest

by Atish Patra

This series implements SBI PMU improvements done in SBI v2.0[1] i.e. PMU snapshot and fw_read_hi() functions. SBI v2.0 introduced PMU snapshot feature which allows the SBI implementation to provide counter information (i.e. values/overflow status) via a shared memory between the SBI implementation and supervisor OS. This allows to minimize the number of traps in when perf being used inside a kvm guest as it relies on SBI PMU + trap/emulation of the counters. The current set of ratified RISC-V specification also doesn't allow scountovf to be trap/emulated by the hypervisor. The SBI PMU snapshot bridges the gap in ISA as well and enables perf sampling in the guest. However, LCOFI in the guest only works via IRQ filtering in AIA specification. That's why, AIA has to be enabled in the hardware (at least the Ssaia extension) in order to use the sampling support in the perf. Here are the patch wise implementation details. PATCH 1,6,7 : Generic cleanups/improvements. PATCH 2,3,10 : FW_READ_HI function implementation PATCH 4-5: Add PMU snapshot feature in sbi pmu driver PATCH 6-7: KVM implementation for snapshot and sampling in kvm guests PATCH 11-15: KVM selftests for SBI PMU extension The series is based on kvm-next and is available at: https://github.com/atishp04/linux/tree/kvm_pmu_snapshot_v4 The series is based on kvm-riscv/queue branch + fixes suggested on the following series https://patchwork.kernel.org/project/kvm/cover/cover.1705916069.git.haibo1.… The kvmtool patch is also available at: https://github.com/atishp04/kvmtool/tree/sscofpmf It also requires Ssaia ISA extension to be present in the hardware in order to get perf sampling support in the guest. In Qemu virt machine, it can be done by the following config. ``` -cpu rv64,sscofpmf=true,x-ssaia=true ``` There is no other dependencies on AIA apart from that. Thus, Ssaia must be disabled for the guest if AIA patches are not available. Here is the example command. ``` ./lkvm-static run -m 256 -c2 --console serial -p "console=ttyS0 earlycon" --disable-ssaia -k ./Image --debug ``` The series has been tested only in Qemu. Here is the snippet of the perf running inside a kvm guest. =================================================== $ perf record -e cycles -e instructions perf bench sched messaging -g 5 ... $ Running 'sched/messaging' benchmark: ... [ 45.928723] perf_duration_warn: 2 callbacks suppressed [ 45.929000] perf: interrupt took too long (484426 > 483186), lowering kernel.perf_event_max_sample_rate to 250 $ 20 sender and receiver processes per group $ 5 groups == 200 processes run Total time: 14.220 [sec] [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.117 MB perf.data (1942 samples) ] $ perf report --stdio $ To display the perf.data header info, please use --header/--header-only optio> $ $ $ Total Lost Samples: 0 $ $ Samples: 943 of event 'cycles' $ Event count (approx.): 5128976844 $ $ Overhead Command Shared Object Symbol > $ ........ ............... ........................... .....................> $ 7.59% sched-messaging [kernel.kallsyms] [k] memcpy 5.48% sched-messaging [kernel.kallsyms] [k] percpu_counter_ad> 5.24% sched-messaging [kernel.kallsyms] [k] __sbi_rfence_v02_> 4.00% sched-messaging [kernel.kallsyms] [k] _raw_spin_unlock_> 3.79% sched-messaging [kernel.kallsyms] [k] set_pte_range 3.72% sched-messaging [kernel.kallsyms] [k] next_uptodate_fol> 3.46% sched-messaging [kernel.kallsyms] [k] filemap_map_pages 3.31% sched-messaging [kernel.kallsyms] [k] handle_mm_fault 3.20% sched-messaging [kernel.kallsyms] [k] finish_task_switc> 3.16% sched-messaging [kernel.kallsyms] [k] clear_page 3.03% sched-messaging [kernel.kallsyms] [k] mtree_range_walk 2.42% sched-messaging [kernel.kallsyms] [k] flush_icache_pte =================================================== [1] https://github.com/riscv-non-isa/riscv-sbi-doc Changes from v3->v4: 1. Added selftests. 2. Fixed an issue to clear the interrupt pending bits. 3. Fixed the counter index in snapshot memory start function. Changes from v2->v3: 1. Fixed a patchwork warning on patch6. 2. Fixed a comment formatting & nit fix in PATCH 3 & 5. 3. Moved the hvien update and sscofpmf enabling to PATCH 9 from PATCH 8. Changes from v1->v2: 1. Fixed warning/errors from patchwork CI. 2. Rebased on top of kvm-next. 3. Added Acked-by tags. Changes from RFC->v1: 1. Addressed all the comments on RFC series. 2. Removed PATCH2 and merged into later patches. 3. Added 2 more patches for minor fixes. 4. Fixed KVM boot issue without Ssaia and made sscofpmf in guest dependent on Ssaia in the host. Atish Patra (15): RISC-V: Fix the typo in Scountovf CSR name RISC-V: Add FIRMWARE_READ_HI definition drivers/perf: riscv: Read upper bits of a firmware counter RISC-V: Add SBI PMU snapshot definitions drivers/perf: riscv: Implement SBI PMU snapshot function RISC-V: KVM: No need to update the counter value during reset RISC-V: KVM: No need to exit to the user space if perf event failed RISC-V: KVM: Implement SBI PMU Snapshot feature RISC-V: KVM: Add perf sampling support for guests RISC-V: KVM: Support 64 bit firmware counters on RV32 KVM: riscv: selftests: Add Sscofpmf to get-reg-list test KVM: riscv: selftests: Add SBI PMU extension definitions KVM: riscv: selftests: Add SBI PMU selftest KVM: riscv: selftests: Add a test for PMU snapshot functionality KVM: riscv: selftests: Add a test for counter overflow arch/riscv/include/asm/csr.h | 5 +- arch/riscv/include/asm/errata_list.h | 2 +- arch/riscv/include/asm/kvm_vcpu_pmu.h | 14 +- arch/riscv/include/asm/sbi.h | 12 + arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/aia.c | 5 + arch/riscv/kvm/vcpu.c | 14 +- arch/riscv/kvm/vcpu_onereg.c | 9 +- arch/riscv/kvm/vcpu_pmu.c | 247 +++++++- arch/riscv/kvm/vcpu_sbi_pmu.c | 15 +- drivers/perf/riscv_pmu.c | 1 + drivers/perf/riscv_pmu_sbi.c | 229 ++++++- include/linux/perf/riscv_pmu.h | 6 + tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/riscv/processor.h | 92 +++ .../selftests/kvm/lib/riscv/processor.c | 12 + .../selftests/kvm/riscv/get-reg-list.c | 4 + tools/testing/selftests/kvm/riscv/sbi_pmu.c | 588 ++++++++++++++++++ 18 files changed, 1212 insertions(+), 45 deletions(-) create mode 100644 tools/testing/selftests/kvm/riscv/sbi_pmu.c -- 2.34.1

4 weeks

7
55
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Linux-kselftest-mirror March 2024