diff options
Diffstat (limited to '0001-futex.patch')
| -rw-r--r-- | 0001-futex.patch | 1028 |
1 files changed, 0 insertions, 1028 deletions
diff --git a/0001-futex.patch b/0001-futex.patch deleted file mode 100644 index 72bf55a8f28d..000000000000 --- a/0001-futex.patch +++ /dev/null @@ -1,1028 +0,0 @@ -From 3c0db5afb3180941bf51dd7c12541514d774a250 Mon Sep 17 00:00:00 2001 -From: Gabriel Krisman Bertazi <krisman@collabora.com> -Date: Thu, 13 Feb 2020 18:45:22 -0300 -Subject: [PATCH 1/4] futex: Implement mechanism to wait on any of several - futexes -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -This is a new futex operation, called FUTEX_WAIT_MULTIPLE, which allows -a thread to wait on several futexes at the same time, and be awoken by -any of them. In a sense, it implements one of the features that was -supported by pooling on the old FUTEX_FD interface. - -The use case lies in the Wine implementation of the Windows NT interface -WaitMultipleObjects. This Windows API function allows a thread to sleep -waiting on the first of a set of event sources (mutexes, timers, signal, -console input, etc) to signal. Considering this is a primitive -synchronization operation for Windows applications, being able to quickly -signal events on the producer side, and quickly go to sleep on the -consumer side is essential for good performance of those running over Wine. - -Wine developers have an implementation that uses eventfd, but it suffers -from FD exhaustion (there is applications that go to the order of -multi-milion FDs), and higher CPU utilization than this new operation. - -The futex list is passed as an array of `struct futex_wait_block` -(pointer, value, bitset) to the kernel, which will enqueue all of them -and sleep if none was already triggered. It returns a hint of which -futex caused the wake up event to userspace, but the hint doesn't -guarantee that is the only futex triggered. Before calling the syscall -again, userspace should traverse the list, trying to re-acquire any of -the other futexes, to prevent an immediate -EWOULDBLOCK return code from -the kernel. - -This was tested using three mechanisms: - -1) By reimplementing FUTEX_WAIT in terms of FUTEX_WAIT_MULTIPLE and -running the unmodified tools/testing/selftests/futex and a full linux -distro on top of this kernel. - -2) By an example code that exercises the FUTEX_WAIT_MULTIPLE path on a -multi-threaded, event-handling setup. - -3) By running the Wine fsync with Valve's Proton compatibility code -implementation and executing multi-threaded applications, in particular -modern games, on top of this implementation. - -Changes were tested for the following ABIs: x86_64, i386 and x32. -Support for x32 applications is not implemented since it would -take a major rework adding a new entry point and splitting the current -futex 64 entry point in two and we can't change the current x32 syscall -number without breaking user space compatibility. - -CC: Steven Rostedt <rostedt@goodmis.org> -Cc: Richard Yao <ryao@gentoo.org> -Cc: Thomas Gleixner <tglx@linutronix.de> -Cc: Peter Zijlstra <peterz@infradead.org> -Co-developed-by: Zebediah Figura <z.figura12@gmail.com> -Signed-off-by: Zebediah Figura <z.figura12@gmail.com> -Co-developed-by: Steven Noonan <steven@valvesoftware.com> -Signed-off-by: Steven Noonan <steven@valvesoftware.com> -Co-developed-by: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com> -Signed-off-by: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com> -Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> -[Added compatibility code] -Co-developed-by: André Almeida <andrealmeid@collabora.com> -Signed-off-by: André Almeida <andrealmeid@collabora.com> ---- - include/uapi/linux/futex.h | 20 ++ - kernel/futex.c | 363 ++++++++++++++++++++++++++++++++++++- - 2 files changed, 379 insertions(+), 4 deletions(-) - -diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h -index a89eb0acc..a3e760886 100644 ---- a/include/uapi/linux/futex.h -+++ b/include/uapi/linux/futex.h -@@ -21,6 +21,7 @@ - #define FUTEX_WAKE_BITSET 10 - #define FUTEX_WAIT_REQUEUE_PI 11 - #define FUTEX_CMP_REQUEUE_PI 12 -+#define FUTEX_WAIT_MULTIPLE 31 - - #define FUTEX_PRIVATE_FLAG 128 - #define FUTEX_CLOCK_REALTIME 256 -@@ -40,6 +41,8 @@ - FUTEX_PRIVATE_FLAG) - #define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \ - FUTEX_PRIVATE_FLAG) -+#define FUTEX_WAIT_MULTIPLE_PRIVATE (FUTEX_WAIT_MULTIPLE | \ -+ FUTEX_PRIVATE_FLAG) - - /* - * Support for robust futexes: the kernel cleans up held futexes at -@@ -150,4 +153,21 @@ struct robust_list_head { - (((op & 0xf) << 28) | ((cmp & 0xf) << 24) \ - | ((oparg & 0xfff) << 12) | (cmparg & 0xfff)) - -+/* -+ * Maximum number of multiple futexes to wait for -+ */ -+#define FUTEX_MULTIPLE_MAX_COUNT 128 -+ -+/** -+ * struct futex_wait_block - Block of futexes to be waited for -+ * @uaddr: User address of the futex -+ * @val: Futex value expected by userspace -+ * @bitset: Bitset for the optional bitmasked wakeup -+ */ -+struct futex_wait_block { -+ __u32 __user *uaddr; -+ __u32 val; -+ __u32 bitset; -+}; -+ - #endif /* _UAPI_LINUX_FUTEX_H */ -diff --git a/kernel/futex.c b/kernel/futex.c -index b59532862..2fbfb0b80 100644 ---- a/kernel/futex.c -+++ b/kernel/futex.c -@@ -214,6 +214,8 @@ struct futex_pi_state { - * @rt_waiter: rt_waiter storage for use with requeue_pi - * @requeue_pi_key: the requeue_pi target futex key - * @bitset: bitset for the optional bitmasked wakeup -+ * @uaddr: userspace address of futex -+ * @uval: expected futex's value - * - * We use this hashed waitqueue, instead of a normal wait_queue_entry_t, so - * we can wake only the relevant ones (hashed queues may be shared). -@@ -236,6 +238,8 @@ struct futex_q { - struct rt_mutex_waiter *rt_waiter; - union futex_key *requeue_pi_key; - u32 bitset; -+ u32 __user *uaddr; -+ u32 uval; - } __randomize_layout; - - static const struct futex_q futex_q_init = { -@@ -2346,6 +2350,29 @@ static int unqueue_me(struct futex_q *q) - return ret; - } - -+/** -+ * unqueue_multiple() - Remove several futexes from their futex_hash_bucket -+ * @q: The list of futexes to unqueue -+ * @count: Number of futexes in the list -+ * -+ * Helper to unqueue a list of futexes. This can't fail. -+ * -+ * Return: -+ * - >=0 - Index of the last futex that was awoken; -+ * - -1 - If no futex was awoken -+ */ -+static int unqueue_multiple(struct futex_q *q, int count) -+{ -+ int ret = -1; -+ int i; -+ -+ for (i = 0; i < count; i++) { -+ if (!unqueue_me(&q[i])) -+ ret = i; -+ } -+ return ret; -+} -+ - /* - * PI futexes can not be requeued and must remove themself from the - * hash bucket. The hash bucket lock (i.e. lock_ptr) is held on entry -@@ -2709,6 +2736,211 @@ static int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags, - return ret; - } - -+/** -+ * futex_wait_multiple_setup() - Prepare to wait and enqueue multiple futexes -+ * @qs: The corresponding futex list -+ * @count: The size of the lists -+ * @flags: Futex flags (FLAGS_SHARED, etc.) -+ * @awaken: Index of the last awoken futex -+ * -+ * Prepare multiple futexes in a single step and enqueue them. This may fail if -+ * the futex list is invalid or if any futex was already awoken. On success the -+ * task is ready to interruptible sleep. -+ * -+ * Return: -+ * - 1 - One of the futexes was awaken by another thread -+ * - 0 - Success -+ * - <0 - -EFAULT, -EWOULDBLOCK or -EINVAL -+ */ -+static int futex_wait_multiple_setup(struct futex_q *qs, int count, -+ unsigned int flags, int *awaken) -+{ -+ struct futex_hash_bucket *hb; -+ int ret, i; -+ u32 uval; -+ -+ /* -+ * Enqueuing multiple futexes is tricky, because we need to -+ * enqueue each futex in the list before dealing with the next -+ * one to avoid deadlocking on the hash bucket. But, before -+ * enqueuing, we need to make sure that current->state is -+ * TASK_INTERRUPTIBLE, so we don't absorb any awake events, which -+ * cannot be done before the get_futex_key of the next key, -+ * because it calls get_user_pages, which can sleep. Thus, we -+ * fetch the list of futexes keys in two steps, by first pinning -+ * all the memory keys in the futex key, and only then we read -+ * each key and queue the corresponding futex. -+ */ -+retry: -+ for (i = 0; i < count; i++) { -+ qs[i].key = FUTEX_KEY_INIT; -+ ret = get_futex_key(qs[i].uaddr, flags & FLAGS_SHARED, -+ &qs[i].key, FUTEX_READ); -+ if (unlikely(ret)) { -+ for (--i; i >= 0; i--) -+ put_futex_key(&qs[i].key); -+ return ret; -+ } -+ } -+ -+ set_current_state(TASK_INTERRUPTIBLE); -+ -+ for (i = 0; i < count; i++) { -+ struct futex_q *q = &qs[i]; -+ -+ hb = queue_lock(q); -+ -+ ret = get_futex_value_locked(&uval, q->uaddr); -+ if (ret) { -+ /* -+ * We need to try to handle the fault, which -+ * cannot be done without sleep, so we need to -+ * undo all the work already done, to make sure -+ * we don't miss any wake ups. Therefore, clean -+ * up, handle the fault and retry from the -+ * beginning. -+ */ -+ queue_unlock(hb); -+ -+ /* -+ * Keys 0..(i-1) are implicitly put -+ * on unqueue_multiple. -+ */ -+ put_futex_key(&q->key); -+ -+ *awaken = unqueue_multiple(qs, i); -+ -+ __set_current_state(TASK_RUNNING); -+ -+ /* -+ * On a real fault, prioritize the error even if -+ * some other futex was awoken. Userspace gave -+ * us a bad address, -EFAULT them. -+ */ -+ ret = get_user(uval, q->uaddr); -+ if (ret) -+ return ret; -+ -+ /* -+ * Even if the page fault was handled, If -+ * something was already awaken, we can safely -+ * give up and succeed to give a hint for userspace to -+ * acquire the right futex faster. -+ */ -+ if (*awaken >= 0) -+ return 1; -+ -+ goto retry; -+ } -+ -+ if (uval != q->uval) { -+ queue_unlock(hb); -+ -+ put_futex_key(&qs[i].key); -+ -+ /* -+ * If something was already awaken, we can -+ * safely ignore the error and succeed. -+ */ -+ *awaken = unqueue_multiple(qs, i); -+ __set_current_state(TASK_RUNNING); -+ if (*awaken >= 0) -+ return 1; -+ -+ return -EWOULDBLOCK; -+ } -+ -+ /* -+ * The bucket lock can't be held while dealing with the -+ * next futex. Queue each futex at this moment so hb can -+ * be unlocked. -+ */ -+ queue_me(&qs[i], hb); -+ } -+ return 0; -+} -+ -+/** -+ * futex_wait_multiple() - Prepare to wait on and enqueue several futexes -+ * @qs: The list of futexes to wait on -+ * @op: Operation code from futex's syscall -+ * @count: The number of objects -+ * @abs_time: Timeout before giving up and returning to userspace -+ * -+ * Entry point for the FUTEX_WAIT_MULTIPLE futex operation, this function -+ * sleeps on a group of futexes and returns on the first futex that -+ * triggered, or after the timeout has elapsed. -+ * -+ * Return: -+ * - >=0 - Hint to the futex that was awoken -+ * - <0 - On error -+ */ -+static int futex_wait_multiple(struct futex_q *qs, int op, -+ u32 count, ktime_t *abs_time) -+{ -+ struct hrtimer_sleeper timeout, *to; -+ int ret, flags = 0, hint = 0; -+ unsigned int i; -+ -+ if (!(op & FUTEX_PRIVATE_FLAG)) -+ flags |= FLAGS_SHARED; -+ -+ if (op & FUTEX_CLOCK_REALTIME) -+ flags |= FLAGS_CLOCKRT; -+ -+ to = futex_setup_timer(abs_time, &timeout, flags, 0); -+ while (1) { -+ ret = futex_wait_multiple_setup(qs, count, flags, &hint); -+ if (ret) { -+ if (ret > 0) { -+ /* A futex was awaken during setup */ -+ ret = hint; -+ } -+ break; -+ } -+ -+ if (to) -+ hrtimer_start_expires(&to->timer, HRTIMER_MODE_ABS); -+ -+ /* -+ * Avoid sleeping if another thread already tried to -+ * wake us. -+ */ -+ for (i = 0; i < count; i++) { -+ if (plist_node_empty(&qs[i].list)) -+ break; -+ } -+ -+ if (i == count && (!to || to->task)) -+ freezable_schedule(); -+ -+ ret = unqueue_multiple(qs, count); -+ -+ __set_current_state(TASK_RUNNING); -+ -+ if (ret >= 0) -+ break; -+ if (to && !to->task) { -+ ret = -ETIMEDOUT; -+ break; -+ } else if (signal_pending(current)) { -+ ret = -ERESTARTSYS; -+ break; -+ } -+ /* -+ * The final case is a spurious wakeup, for -+ * which just retry. -+ */ -+ } -+ -+ if (to) { -+ hrtimer_cancel(&to->timer); -+ destroy_hrtimer_on_stack(&to->timer); -+ } -+ -+ return ret; -+} -+ - static int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, - ktime_t *abs_time, u32 bitset) - { -@@ -3833,6 +4065,43 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, - return -ENOSYS; - } - -+/** -+ * futex_read_wait_block - Read an array of futex_wait_block from userspace -+ * @uaddr: Userspace address of the block -+ * @count: Number of blocks to be read -+ * -+ * This function creates and allocate an array of futex_q (we zero it to -+ * initialize the fields) and then, for each futex_wait_block element from -+ * userspace, fill a futex_q element with proper values. -+ */ -+inline struct futex_q *futex_read_wait_block(u32 __user *uaddr, u32 count) -+{ -+ unsigned int i; -+ struct futex_q *qs; -+ struct futex_wait_block fwb; -+ struct futex_wait_block __user *entry = -+ (struct futex_wait_block __user *)uaddr; -+ -+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT) -+ return ERR_PTR(-EINVAL); -+ -+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL); -+ if (!qs) -+ return ERR_PTR(-ENOMEM); -+ -+ for (i = 0; i < count; i++) { -+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) { -+ kfree(qs); -+ return ERR_PTR(-EFAULT); -+ } -+ -+ qs[i].uaddr = fwb.uaddr; -+ qs[i].uval = fwb.val; -+ qs[i].bitset = fwb.bitset; -+ } -+ -+ return qs; -+} - - SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, - struct __kernel_timespec __user *, utime, u32 __user *, uaddr2, -@@ -3845,7 +4114,8 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, - - if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || - cmd == FUTEX_WAIT_BITSET || -- cmd == FUTEX_WAIT_REQUEUE_PI)) { -+ cmd == FUTEX_WAIT_REQUEUE_PI || -+ cmd == FUTEX_WAIT_MULTIPLE)) { - if (unlikely(should_fail_futex(!(op & FUTEX_PRIVATE_FLAG)))) - return -EFAULT; - if (get_timespec64(&ts, utime)) -@@ -3854,7 +4124,7 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, - return -EINVAL; - - t = timespec64_to_ktime(ts); -- if (cmd == FUTEX_WAIT) -+ if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE) - t = ktime_add_safe(ktime_get(), t); - tp = &t; - } -@@ -3866,6 +4136,25 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, - cmd == FUTEX_CMP_REQUEUE_PI || cmd == FUTEX_WAKE_OP) - val2 = (u32) (unsigned long) utime; - -+ if (cmd == FUTEX_WAIT_MULTIPLE) { -+ int ret; -+ struct futex_q *qs; -+ -+#ifdef CONFIG_X86_X32 -+ if (unlikely(in_x32_syscall())) -+ return -ENOSYS; -+#endif -+ qs = futex_read_wait_block(uaddr, val); -+ -+ if (IS_ERR(qs)) -+ return PTR_ERR(qs); -+ -+ ret = futex_wait_multiple(qs, op, val, tp); -+ kfree(qs); -+ -+ return ret; -+ } -+ - return do_futex(uaddr, op, val, tp, uaddr2, val2, val3); - } - -@@ -4028,6 +4317,58 @@ COMPAT_SYSCALL_DEFINE3(get_robust_list, int, pid, - #endif /* CONFIG_COMPAT */ - - #ifdef CONFIG_COMPAT_32BIT_TIME -+/** -+ * struct compat_futex_wait_block - Block of futexes to be waited for -+ * @uaddr: User address of the futex (compatible pointer) -+ * @val: Futex value expected by userspace -+ * @bitset: Bitset for the optional bitmasked wakeup -+ */ -+struct compat_futex_wait_block { -+ compat_uptr_t uaddr; -+ __u32 pad; -+ __u32 val; -+ __u32 bitset; -+}; -+ -+/** -+ * compat_futex_read_wait_block - Read an array of futex_wait_block from -+ * userspace -+ * @uaddr: Userspace address of the block -+ * @count: Number of blocks to be read -+ * -+ * This function does the same as futex_read_wait_block(), except that it -+ * converts the pointer to the futex from the compat version to the regular one. -+ */ -+inline struct futex_q *compat_futex_read_wait_block(u32 __user *uaddr, -+ u32 count) -+{ -+ unsigned int i; -+ struct futex_q *qs; -+ struct compat_futex_wait_block fwb; -+ struct compat_futex_wait_block __user *entry = -+ (struct compat_futex_wait_block __user *)uaddr; -+ -+ if (!count || count > FUTEX_MULTIPLE_MAX_COUNT) -+ return ERR_PTR(-EINVAL); -+ -+ qs = kcalloc(count, sizeof(*qs), GFP_KERNEL); -+ if (!qs) -+ return ERR_PTR(-ENOMEM); -+ -+ for (i = 0; i < count; i++) { -+ if (copy_from_user(&fwb, &entry[i], sizeof(fwb))) { -+ kfree(qs); -+ return ERR_PTR(-EFAULT); -+ } -+ -+ qs[i].uaddr = compat_ptr(fwb.uaddr); -+ qs[i].uval = fwb.val; -+ qs[i].bitset = fwb.bitset; -+ } -+ -+ return qs; -+} -+ - SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val, - struct old_timespec32 __user *, utime, u32 __user *, uaddr2, - u32, val3) -@@ -4039,14 +4380,15 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val, - - if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || - cmd == FUTEX_WAIT_BITSET || -- cmd == FUTEX_WAIT_REQUEUE_PI)) { -+ cmd == FUTEX_WAIT_REQUEUE_PI || -+ cmd == FUTEX_WAIT_MULTIPLE)) { - if (get_old_timespec32(&ts, utime)) - return -EFAULT; - if (!timespec64_valid(&ts)) - return -EINVAL; - - t = timespec64_to_ktime(ts); -- if (cmd == FUTEX_WAIT) -+ if (cmd == FUTEX_WAIT || cmd == FUTEX_WAIT_MULTIPLE) - t = ktime_add_safe(ktime_get(), t); - tp = &t; - } -@@ -4054,6 +4396,19 @@ SYSCALL_DEFINE6(futex_time32, u32 __user *, uaddr, int, op, u32, val, - cmd == FUTEX_CMP_REQUEUE_PI || cmd == FUTEX_WAKE_OP) - val2 = (int) (unsigned long) utime; - -+ if (cmd == FUTEX_WAIT_MULTIPLE) { -+ int ret; -+ struct futex_q *qs = compat_futex_read_wait_block(uaddr, val); -+ -+ if (IS_ERR(qs)) -+ return PTR_ERR(qs); -+ -+ ret = futex_wait_multiple(qs, op, val, tp); -+ kfree(qs); -+ -+ return ret; -+ } -+ - return do_futex(uaddr, op, val, tp, uaddr2, val2, val3); - } - #endif /* CONFIG_COMPAT_32BIT_TIME */ --- -2.27.0.rc2 - - -From 3b2db8473486da199622782b28a9de69c4446323 Mon Sep 17 00:00:00 2001 -From: Gabriel Krisman Bertazi <krisman@collabora.com> -Date: Thu, 13 Feb 2020 18:45:23 -0300 -Subject: [PATCH 2/4] selftests: futex: Add FUTEX_WAIT_MULTIPLE timeout test -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -Add test for timeout when waiting for multiple futexes. Skip the test if -it's a x32 application and the kernel returned the approtiaded error, -since this ABI is not supported for this operation. - -Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> -Co-developed-by: André Almeida <andrealmeid@collabora.com> -Signed-off-by: André Almeida <andrealmeid@collabora.com> ---- - .../futex/functional/futex_wait_timeout.c | 38 ++++++++++++++++++- - .../selftests/futex/include/futextest.h | 22 +++++++++++ - 2 files changed, 58 insertions(+), 2 deletions(-) - -diff --git a/tools/testing/selftests/futex/functional/futex_wait_timeout.c b/tools/testing/selftests/futex/functional/futex_wait_timeout.c -index ee55e6d38..2a63e1c2c 100644 ---- a/tools/testing/selftests/futex/functional/futex_wait_timeout.c -+++ b/tools/testing/selftests/futex/functional/futex_wait_timeout.c -@@ -11,6 +11,7 @@ - * - * HISTORY - * 2009-Nov-6: Initial version by Darren Hart <dvhart@linux.intel.com> -+ * 2019-Dec-13: Add WAIT_MULTIPLE test by Krisman <krisman@collabora.com> - * - *****************************************************************************/ - -@@ -41,6 +42,8 @@ int main(int argc, char *argv[]) - { - futex_t f1 = FUTEX_INITIALIZER; - struct timespec to; -+ time_t secs; -+ struct futex_wait_block fwb = {&f1, f1, 0}; - int res, ret = RET_PASS; - int c; - -@@ -65,7 +68,7 @@ int main(int argc, char *argv[]) - } - - ksft_print_header(); -- ksft_set_plan(1); -+ ksft_set_plan(2); - ksft_print_msg("%s: Block on a futex and wait for timeout\n", - basename(argv[0])); - ksft_print_msg("\tArguments: timeout=%ldns\n", timeout_ns); -@@ -79,8 +82,39 @@ int main(int argc, char *argv[]) - if (!res || errno != ETIMEDOUT) { - fail("futex_wait returned %d\n", ret < 0 ? errno : ret); - ret = RET_FAIL; -+ } else -+ ksft_test_result_pass("futex_wait timeout succeeds\n"); -+ -+ info("Calling futex_wait_multiple on f1: %u @ %p\n", f1, &f1); -+ -+ /* Setup absolute time */ -+ ret = clock_gettime(CLOCK_REALTIME, &to); -+ secs = (to.tv_nsec + timeout_ns) / 1000000000; -+ to.tv_nsec = ((int64_t)to.tv_nsec + timeout_ns) % 1000000000; -+ to.tv_sec += secs; -+ info("to.tv_sec = %ld\n", to.tv_sec); -+ info("to.tv_nsec = %ld\n", to.tv_nsec); -+ -+ res = futex_wait_multiple(&fwb, 1, &to, -+ FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME); -+ -+#ifdef __ILP32__ -+ if (res == -1 && errno == ENOSYS) { -+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n"); -+ } else { -+ ksft_test_result_fail("futex_wait_multiple returned %d\n", -+ res < 0 ? errno : res); -+ ret = RET_FAIL; - } -+#else -+ if (!res || errno != ETIMEDOUT) { -+ ksft_test_result_fail("futex_wait_multiple returned %d\n", -+ res < 0 ? errno : res); -+ ret = RET_FAIL; -+ } else -+ ksft_test_result_pass("futex_wait_multiple timeout succeeds\n"); -+#endif /* __ILP32__ */ - -- print_result(TEST_NAME, ret); -+ ksft_print_cnts(); - return ret; - } -diff --git a/tools/testing/selftests/futex/include/futextest.h b/tools/testing/selftests/futex/include/futextest.h -index ddbcfc9b7..bb103bef4 100644 ---- a/tools/testing/selftests/futex/include/futextest.h -+++ b/tools/testing/selftests/futex/include/futextest.h -@@ -38,6 +38,14 @@ typedef volatile u_int32_t futex_t; - #ifndef FUTEX_CMP_REQUEUE_PI - #define FUTEX_CMP_REQUEUE_PI 12 - #endif -+#ifndef FUTEX_WAIT_MULTIPLE -+#define FUTEX_WAIT_MULTIPLE 13 -+struct futex_wait_block { -+ futex_t *uaddr; -+ futex_t val; -+ __u32 bitset; -+}; -+#endif - #ifndef FUTEX_WAIT_REQUEUE_PI_PRIVATE - #define FUTEX_WAIT_REQUEUE_PI_PRIVATE (FUTEX_WAIT_REQUEUE_PI | \ - FUTEX_PRIVATE_FLAG) -@@ -80,6 +88,20 @@ futex_wait(futex_t *uaddr, futex_t val, struct timespec *timeout, int opflags) - return futex(uaddr, FUTEX_WAIT, val, timeout, NULL, 0, opflags); - } - -+/** -+ * futex_wait_multiple() - block on several futexes with optional timeout -+ * @fwb: wait block user space address -+ * @count: number of entities at fwb -+ * @timeout: absolute timeout -+ */ -+static inline int -+futex_wait_multiple(struct futex_wait_block *fwb, int count, -+ struct timespec *timeout, int opflags) -+{ -+ return futex(fwb, FUTEX_WAIT_MULTIPLE, count, timeout, NULL, 0, -+ opflags); -+} -+ - /** - * futex_wake() - wake one or more tasks blocked on uaddr - * @nr_wake: wake up to this many tasks --- -2.27.0.rc2 - - -From b285216bc7b31eeba9b0e8081fe312bac7514931 Mon Sep 17 00:00:00 2001 -From: Gabriel Krisman Bertazi <krisman@collabora.com> -Date: Thu, 13 Feb 2020 18:45:24 -0300 -Subject: [PATCH 3/4] selftests: futex: Add FUTEX_WAIT_MULTIPLE wouldblock test -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -Add test for wouldblock return when waiting for multiple futexes. Skip -the test if it's a x32 application and the kernel returned the approtiaded -error, since this ABI is not supported for this operation. - -Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> -Co-developed-by: André Almeida <andrealmeid@collabora.com> -Signed-off-by: André Almeida <andrealmeid@collabora.com> ---- - .../futex/functional/futex_wait_wouldblock.c | 28 +++++++++++++++++-- - 1 file changed, 26 insertions(+), 2 deletions(-) - -diff --git a/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c b/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c -index 0ae390ff8..bcbac0429 100644 ---- a/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c -+++ b/tools/testing/selftests/futex/functional/futex_wait_wouldblock.c -@@ -12,6 +12,7 @@ - * - * HISTORY - * 2009-Nov-14: Initial version by Gowrishankar <gowrishankar.m@in.ibm.com> -+ * 2019-Dec-13: Add WAIT_MULTIPLE test by Krisman <krisman@collabora.com> - * - *****************************************************************************/ - -@@ -40,6 +41,7 @@ int main(int argc, char *argv[]) - { - struct timespec to = {.tv_sec = 0, .tv_nsec = timeout_ns}; - futex_t f1 = FUTEX_INITIALIZER; -+ struct futex_wait_block fwb = {&f1, f1+1, 0}; - int res, ret = RET_PASS; - int c; - -@@ -61,7 +63,7 @@ int main(int argc, char *argv[]) - } - - ksft_print_header(); -- ksft_set_plan(1); -+ ksft_set_plan(2); - ksft_print_msg("%s: Test the unexpected futex value in FUTEX_WAIT\n", - basename(argv[0])); - -@@ -71,8 +73,30 @@ int main(int argc, char *argv[]) - fail("futex_wait returned: %d %s\n", - res ? errno : res, res ? strerror(errno) : ""); - ret = RET_FAIL; -+ } else -+ ksft_test_result_pass("futex_wait wouldblock succeeds\n"); -+ -+ info("Calling futex_wait_multiple on f1: %u @ %p with val=%u\n", -+ f1, &f1, f1+1); -+ res = futex_wait_multiple(&fwb, 1, NULL, FUTEX_PRIVATE_FLAG); -+ -+#ifdef __ILP32__ -+ if (res != -1 || errno != ENOSYS) { -+ ksft_test_result_fail("futex_wait_multiple returned %d\n", -+ res < 0 ? errno : res); -+ ret = RET_FAIL; -+ } else { -+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n"); -+ } -+#else -+ if (!res || errno != EWOULDBLOCK) { -+ ksft_test_result_fail("futex_wait_multiple returned %d\n", -+ res < 0 ? errno : res); -+ ret = RET_FAIL; - } -+ ksft_test_result_pass("futex_wait_multiple wouldblock succeeds\n"); -+#endif /* __ILP32__ */ - -- print_result(TEST_NAME, ret); -+ ksft_print_cnts(); - return ret; - } --- -2.27.0.rc2 - - -From c2a6902699480877846a07e7567fbce94b370cce Mon Sep 17 00:00:00 2001 -From: Gabriel Krisman Bertazi <krisman@collabora.com> -Date: Thu, 13 Feb 2020 18:45:25 -0300 -Subject: [PATCH 4/4] selftests: futex: Add FUTEX_WAIT_MULTIPLE wake up test -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -Add test for wait at multiple futexes mechanism. Skip the test if it's a -x32 application and the kernel returned the approtiaded error, since this -ABI is not supported for this operation. - -Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> -Co-developed-by: André Almeida <andrealmeid@collabora.com> -Signed-off-by: André Almeida <andrealmeid@collabora.com> ---- - .../selftests/futex/functional/.gitignore | 1 + - .../selftests/futex/functional/Makefile | 3 +- - .../futex/functional/futex_wait_multiple.c | 173 ++++++++++++++++++ - .../testing/selftests/futex/functional/run.sh | 3 + - 4 files changed, 179 insertions(+), 1 deletion(-) - create mode 100644 tools/testing/selftests/futex/functional/futex_wait_multiple.c - -diff --git a/tools/testing/selftests/futex/functional/.gitignore b/tools/testing/selftests/futex/functional/.gitignore -index 0efcd494d..03a4bedce 100644 ---- a/tools/testing/selftests/futex/functional/.gitignore -+++ b/tools/testing/selftests/futex/functional/.gitignore -@@ -6,3 +6,4 @@ futex_wait_private_mapped_file - futex_wait_timeout - futex_wait_uninitialized_heap - futex_wait_wouldblock -+futex_wait_multiple -diff --git a/tools/testing/selftests/futex/functional/Makefile b/tools/testing/selftests/futex/functional/Makefile -index 23207829e..26562f2d7 100644 ---- a/tools/testing/selftests/futex/functional/Makefile -+++ b/tools/testing/selftests/futex/functional/Makefile -@@ -14,7 +14,8 @@ TEST_GEN_FILES := \ - futex_requeue_pi_signal_restart \ - futex_requeue_pi_mismatched_ops \ - futex_wait_uninitialized_heap \ -- futex_wait_private_mapped_file -+ futex_wait_private_mapped_file \ -+ futex_wait_multiple - - TEST_PROGS := run.sh - -diff --git a/tools/testing/selftests/futex/functional/futex_wait_multiple.c b/tools/testing/selftests/futex/functional/futex_wait_multiple.c -new file mode 100644 -index 000000000..b48422e79 ---- /dev/null -+++ b/tools/testing/selftests/futex/functional/futex_wait_multiple.c -@@ -0,0 +1,173 @@ -+// SPDX-License-Identifier: GPL-2.0-or-later -+/****************************************************************************** -+ * -+ * Copyright © Collabora, Ltd., 2019 -+ * -+ * DESCRIPTION -+ * Test basic semantics of FUTEX_WAIT_MULTIPLE -+ * -+ * AUTHOR -+ * Gabriel Krisman Bertazi <krisman@collabora.com> -+ * -+ * HISTORY -+ * 2019-Dec-13: Initial version by Krisman <krisman@collabora.com> -+ * -+ *****************************************************************************/ -+ -+#include <errno.h> -+#include <getopt.h> -+#include <stdio.h> -+#include <stdlib.h> -+#include <string.h> -+#include <time.h> -+#include <pthread.h> -+#include "futextest.h" -+#include "logging.h" -+ -+#define TEST_NAME "futex-wait-multiple" -+#define timeout_ns 100000 -+#define MAX_COUNT 128 -+#define WAKE_WAIT_US 3000000 -+ -+int ret = RET_PASS; -+char *progname; -+futex_t f[MAX_COUNT] = {0}; -+struct futex_wait_block fwb[MAX_COUNT]; -+ -+void usage(char *prog) -+{ -+ printf("Usage: %s\n", prog); -+ printf(" -c Use color\n"); -+ printf(" -h Display this help message\n"); -+ printf(" -v L Verbosity level: %d=QUIET %d=CRITICAL %d=INFO\n", -+ VQUIET, VCRITICAL, VINFO); -+} -+ -+void test_count_overflow(void) -+{ -+ futex_t f = FUTEX_INITIALIZER; -+ struct futex_wait_block fwb[MAX_COUNT+1]; -+ int res, i; -+ -+ ksft_print_msg("%s: Test a too big number of futexes\n", progname); -+ -+ for (i = 0; i < MAX_COUNT+1; i++) { -+ fwb[i].uaddr = &f; -+ fwb[i].val = f; -+ fwb[i].bitset = 0; -+ } -+ -+ res = futex_wait_multiple(fwb, MAX_COUNT+1, NULL, FUTEX_PRIVATE_FLAG); -+ -+#ifdef __ILP32__ -+ if (res != -1 || errno != ENOSYS) { -+ ksft_test_result_fail("futex_wait_multiple returned %d\n", -+ res < 0 ? errno : res); -+ ret = RET_FAIL; -+ } else { -+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n"); -+ } -+#else -+ if (res != -1 || errno != EINVAL) { -+ ksft_test_result_fail("futex_wait_multiple returned %d\n", -+ res < 0 ? errno : res); -+ ret = RET_FAIL; -+ } else { -+ ksft_test_result_pass("futex_wait_multiple count overflow succeed\n"); -+ } -+ -+#endif /* __ILP32__ */ -+} -+ -+void *waiterfn(void *arg) -+{ -+ int res; -+ -+ res = futex_wait_multiple(fwb, MAX_COUNT, NULL, FUTEX_PRIVATE_FLAG); -+ -+#ifdef __ILP32__ -+ if (res != -1 || errno != ENOSYS) { -+ ksft_test_result_fail("futex_wait_multiple returned %d\n", -+ res < 0 ? errno : res); -+ ret = RET_FAIL; -+ } else { -+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n"); -+ } -+#else -+ if (res < 0) -+ ksft_print_msg("waiter failed %d\n", res); -+ -+ info("futex_wait_multiple: Got hint futex %d was freed\n", res); -+#endif /* __ILP32__ */ -+ -+ return NULL; -+} -+ -+void test_fwb_wakeup(void) -+{ -+ int res, i; -+ pthread_t waiter; -+ -+ ksft_print_msg("%s: Test wake up in a list of futex\n", progname); -+ -+ for (i = 0; i < MAX_COUNT; i++) { -+ fwb[i].uaddr = &f[i]; -+ fwb[i].val = f[i]; -+ fwb[i].bitset = 0xffffffff; -+ } -+ -+ res = pthread_create(&waiter, NULL, waiterfn, NULL); -+ if (res) { -+ ksft_test_result_fail("Creating waiting thread failed"); -+ ksft_exit_fail(); -+ } -+ -+ usleep(WAKE_WAIT_US); -+ res = futex_wake(&(f[MAX_COUNT-1]), 1, FUTEX_PRIVATE_FLAG); -+ if (res != 1) { -+ ksft_test_result_fail("Failed to wake thread res=%d\n", res); -+ ksft_exit_fail(); -+ } -+ -+ pthread_join(waiter, NULL); -+ ksft_test_result_pass("%s succeed\n", __func__); -+} -+ -+int main(int argc, char *argv[]) -+{ -+ int c; -+ -+ while ((c = getopt(argc, argv, "cht:v:")) != -1) { -+ switch (c) { -+ case 'c': -+ log_color(1); -+ break; -+ case 'h': -+ usage(basename(argv[0])); -+ exit(0); -+ case 'v': -+ log_verbosity(atoi(optarg)); -+ break; -+ default: -+ usage(basename(argv[0])); -+ exit(1); -+ } -+ } -+ -+ progname = basename(argv[0]); -+ -+ ksft_print_header(); -+ ksft_set_plan(2); -+ -+ test_count_overflow(); -+ -+#ifdef __ILP32__ -+ // if it's a 32x binary, there's no futex to wakeup -+ ksft_test_result_skip("futex_wait_multiple not supported at x32\n"); -+#else -+ test_fwb_wakeup(); -+#endif /* __ILP32__ */ -+ -+ ksft_print_cnts(); -+ return ret; -+} -diff --git a/tools/testing/selftests/futex/functional/run.sh b/tools/testing/selftests/futex/functional/run.sh -index 1acb6ace1..a8be94f28 100755 ---- a/tools/testing/selftests/futex/functional/run.sh -+++ b/tools/testing/selftests/futex/functional/run.sh -@@ -73,3 +73,6 @@ echo - echo - ./futex_wait_uninitialized_heap $COLOR - ./futex_wait_private_mapped_file $COLOR -+ -+echo -+./futex_wait_multiple $COLOR --- -2.27.0.rc2 - |