From patchwork Mon Sep 13 17:52:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Andr=C3=A9_Almeida?= X-Patchwork-Id: 44954 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id D1AC23858424 for ; Mon, 13 Sep 2021 17:54:45 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D1AC23858424 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1631555685; bh=BIyLhfje6dQw22RwzoGzzOaGdWoyNFnh8cuPBRpCfxI=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=lQdXw+kYF5y62L9L4FcCWz3lJa/n+4JQtHsxQP3HHACRXlKiNjJc8Ys8fN3eSXj0E GZr4rQn0zwSISZ7KP2EcUwZ7ew77tSfI4W0/XyqQLvZBqb+PyKcPs8/hr4fUWkQc+0 ccX0fL6+PLKitGLu4+FrmQaZrZDtX4+MUWwfAbnQ= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by sourceware.org (Postfix) with ESMTPS id 88A063858006 for ; Mon, 13 Sep 2021 17:53:05 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 88A063858006 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: tonyk) with ESMTPSA id B783C1F42CE6 To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart , linux-kernel@vger.kernel.org, Steven Rostedt , Sebastian Andrzej Siewior Subject: [PATCH v3 1/6] futex: Prepare for futex_wait_multiple() Date: Mon, 13 Sep 2021 14:52:44 -0300 Message-Id: <20210913175249.81074-2-andrealmeid@collabora.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210913175249.81074-1-andrealmeid@collabora.com> References: <20210913175249.81074-1-andrealmeid@collabora.com> MIME-Version: 1.0 X-Spam-Status: No, score=-12.1 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_MANYTO, SPF_HELO_PASS, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: =?utf-8?q?Andr=C3=A9_Almeida_via_Libc-alpha?= From: =?utf-8?q?Andr=C3=A9_Almeida?= Reply-To: =?utf-8?q?Andr=C3=A9_Almeida?= Cc: Davidlohr Bueso , libc-alpha@sourceware.org, linux-api@vger.kernel.org, mtk.manpages@gmail.com, =?utf-8?q?Andr=C3=A9_Alm?= =?utf-8?q?eida?= , kernel@collabora.com, krisman@collabora.com Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Make public functions and defines that will be used for futex_wait_multiple() function in next commit. Signed-off-by: André Almeida --- kernel/futex.c | 134 +--------------------------------------------- kernel/futex.h | 140 +++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 142 insertions(+), 132 deletions(-) create mode 100644 kernel/futex.h diff --git a/kernel/futex.c b/kernel/futex.c index c15ad276fd15..32c91f9d7385 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -34,14 +34,11 @@ #include #include #include -#include #include #include #include -#include - -#include +#include "futex.h" #include "locking/rtmutex_common.h" /* @@ -150,22 +147,6 @@ static int __read_mostly futex_cmpxchg_enabled; #endif -/* - * Futex flags used to encode options to functions and preserve them across - * restarts. - */ -#ifdef CONFIG_MMU -# define FLAGS_SHARED 0x01 -#else -/* - * NOMMU does not have per process address space. Let the compiler optimize - * code away. - */ -# define FLAGS_SHARED 0x00 -#endif -#define FLAGS_CLOCKRT 0x02 -#define FLAGS_HAS_TIMEOUT 0x04 - /* * Priority Inheritance state: */ @@ -187,103 +168,6 @@ struct futex_pi_state { union futex_key key; } __randomize_layout; -/** - * struct futex_q - The hashed futex queue entry, one per waiting task - * @list: priority-sorted list of tasks waiting on this futex - * @task: the task waiting on the futex - * @lock_ptr: the hash bucket lock - * @key: the key the futex is hashed on - * @pi_state: optional priority inheritance 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 - * @requeue_state: State field for futex_requeue_pi() - * @requeue_wait: RCU wait for futex_requeue_pi() (RT only) - * - * 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). - * - * A futex_q has a woken state, just like tasks have TASK_RUNNING. - * It is considered woken when plist_node_empty(&q->list) || q->lock_ptr == 0. - * The order of wakeup is always to make the first condition true, then - * the second. - * - * PI futexes are typically woken before they are removed from the hash list via - * the rt_mutex code. See unqueue_me_pi(). - */ -struct futex_q { - struct plist_node list; - - struct task_struct *task; - spinlock_t *lock_ptr; - union futex_key key; - struct futex_pi_state *pi_state; - struct rt_mutex_waiter *rt_waiter; - union futex_key *requeue_pi_key; - u32 bitset; - atomic_t requeue_state; -#ifdef CONFIG_PREEMPT_RT - struct rcuwait requeue_wait; -#endif -} __randomize_layout; - -/* - * On PREEMPT_RT, the hash bucket lock is a 'sleeping' spinlock with an - * underlying rtmutex. The task which is about to be requeued could have - * just woken up (timeout, signal). After the wake up the task has to - * acquire hash bucket lock, which is held by the requeue code. As a task - * can only be blocked on _ONE_ rtmutex at a time, the proxy lock blocking - * and the hash bucket lock blocking would collide and corrupt state. - * - * On !PREEMPT_RT this is not a problem and everything could be serialized - * on hash bucket lock, but aside of having the benefit of common code, - * this allows to avoid doing the requeue when the task is already on the - * way out and taking the hash bucket lock of the original uaddr1 when the - * requeue has been completed. - * - * The following state transitions are valid: - * - * On the waiter side: - * Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_IGNORE - * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_WAIT - * - * On the requeue side: - * Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_INPROGRESS - * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_DONE/LOCKED - * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_NONE (requeue failed) - * Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_DONE/LOCKED - * Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_IGNORE (requeue failed) - * - * The requeue side ignores a waiter with state Q_REQUEUE_PI_IGNORE as this - * signals that the waiter is already on the way out. It also means that - * the waiter is still on the 'wait' futex, i.e. uaddr1. - * - * The waiter side signals early wakeup to the requeue side either through - * setting state to Q_REQUEUE_PI_IGNORE or to Q_REQUEUE_PI_WAIT depending - * on the current state. In case of Q_REQUEUE_PI_IGNORE it can immediately - * proceed to take the hash bucket lock of uaddr1. If it set state to WAIT, - * which means the wakeup is interleaving with a requeue in progress it has - * to wait for the requeue side to change the state. Either to DONE/LOCKED - * or to IGNORE. DONE/LOCKED means the waiter q is now on the uaddr2 futex - * and either blocked (DONE) or has acquired it (LOCKED). IGNORE is set by - * the requeue side when the requeue attempt failed via deadlock detection - * and therefore the waiter q is still on the uaddr1 futex. - */ -enum { - Q_REQUEUE_PI_NONE = 0, - Q_REQUEUE_PI_IGNORE, - Q_REQUEUE_PI_IN_PROGRESS, - Q_REQUEUE_PI_WAIT, - Q_REQUEUE_PI_DONE, - Q_REQUEUE_PI_LOCKED, -}; - -static const struct futex_q futex_q_init = { - /* list gets initialized in queue_me()*/ - .key = FUTEX_KEY_INIT, - .bitset = FUTEX_BITSET_MATCH_ANY, - .requeue_state = ATOMIC_INIT(Q_REQUEUE_PI_NONE), -}; /* * Hash buckets are shared by all the futex_keys that hash to the same @@ -453,7 +337,7 @@ enum futex_access { * Return: Initialized hrtimer_sleeper structure or NULL if no timeout * value given */ -static inline struct hrtimer_sleeper * +inline struct hrtimer_sleeper * futex_setup_timer(ktime_t *time, struct hrtimer_sleeper *timeout, int flags, u64 range_ns) { @@ -4005,20 +3889,6 @@ static __always_inline bool futex_cmd_has_timeout(u32 cmd) return false; } -static __always_inline int -futex_init_timeout(u32 cmd, u32 op, struct timespec64 *ts, ktime_t *t) -{ - if (!timespec64_valid(ts)) - return -EINVAL; - - *t = timespec64_to_ktime(*ts); - if (cmd == FUTEX_WAIT) - *t = ktime_add_safe(ktime_get(), *t); - else if (cmd != FUTEX_LOCK_PI && !(op & FUTEX_CLOCK_REALTIME)) - *t = timens_ktime_to_host(CLOCK_MONOTONIC, *t); - return 0; -} - SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, const struct __kernel_timespec __user *, utime, u32 __user *, uaddr2, u32, val3) diff --git a/kernel/futex.h b/kernel/futex.h new file mode 100644 index 000000000000..c914e0080cf1 --- /dev/null +++ b/kernel/futex.h @@ -0,0 +1,140 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _FUTEX_H +#define _FUTEX_H + +#include + +#include +#include + +/* + * Futex flags used to encode options to functions and preserve them across + * restarts. + */ +#ifdef CONFIG_MMU +# define FLAGS_SHARED 0x01 +#else +/* + * NOMMU does not have per process address space. Let the compiler optimize + * code away. + */ +# define FLAGS_SHARED 0x00 +#endif +#define FLAGS_CLOCKRT 0x02 +#define FLAGS_HAS_TIMEOUT 0x04 + +/** + * struct futex_q - The hashed futex queue entry, one per waiting task + * @list: priority-sorted list of tasks waiting on this futex + * @task: the task waiting on the futex + * @lock_ptr: the hash bucket lock + * @key: the key the futex is hashed on + * @pi_state: optional priority inheritance 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 + * + * 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). + * + * A futex_q has a woken state, just like tasks have TASK_RUNNING. + * It is considered woken when plist_node_empty(&q->list) || q->lock_ptr == 0. + * The order of wakeup is always to make the first condition true, then + * the second. + * + * PI futexes are typically woken before they are removed from the hash list via + * the rt_mutex code. See unqueue_me_pi(). + */ +struct futex_q { + struct plist_node list; + + struct task_struct *task; + spinlock_t *lock_ptr; + union futex_key key; + struct futex_pi_state *pi_state; + struct rt_mutex_waiter *rt_waiter; + union futex_key *requeue_pi_key; + u32 bitset; + atomic_t requeue_state; +#ifdef CONFIG_PREEMPT_RT + struct rcuwait requeue_wait; +#endif +} __randomize_layout; + +/* + * On PREEMPT_RT, the hash bucket lock is a 'sleeping' spinlock with an + * underlying rtmutex. The task which is about to be requeued could have + * just woken up (timeout, signal). After the wake up the task has to + * acquire hash bucket lock, which is held by the requeue code. As a task + * can only be blocked on _ONE_ rtmutex at a time, the proxy lock blocking + * and the hash bucket lock blocking would collide and corrupt state. + * + * On !PREEMPT_RT this is not a problem and everything could be serialized + * on hash bucket lock, but aside of having the benefit of common code, + * this allows to avoid doing the requeue when the task is already on the + * way out and taking the hash bucket lock of the original uaddr1 when the + * requeue has been completed. + * + * The following state transitions are valid: + * + * On the waiter side: + * Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_IGNORE + * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_WAIT + * + * On the requeue side: + * Q_REQUEUE_PI_NONE -> Q_REQUEUE_PI_INPROGRESS + * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_DONE/LOCKED + * Q_REQUEUE_PI_IN_PROGRESS -> Q_REQUEUE_PI_NONE (requeue failed) + * Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_DONE/LOCKED + * Q_REQUEUE_PI_WAIT -> Q_REQUEUE_PI_IGNORE (requeue failed) + * + * The requeue side ignores a waiter with state Q_REQUEUE_PI_IGNORE as this + * signals that the waiter is already on the way out. It also means that + * the waiter is still on the 'wait' futex, i.e. uaddr1. + * + * The waiter side signals early wakeup to the requeue side either through + * setting state to Q_REQUEUE_PI_IGNORE or to Q_REQUEUE_PI_WAIT depending + * on the current state. In case of Q_REQUEUE_PI_IGNORE it can immediately + * proceed to take the hash bucket lock of uaddr1. If it set state to WAIT, + * which means the wakeup is interleaving with a requeue in progress it has + * to wait for the requeue side to change the state. Either to DONE/LOCKED + * or to IGNORE. DONE/LOCKED means the waiter q is now on the uaddr2 futex + * and either blocked (DONE) or has acquired it (LOCKED). IGNORE is set by + * the requeue side when the requeue attempt failed via deadlock detection + * and therefore the waiter q is still on the uaddr1 futex. + */ +enum { + Q_REQUEUE_PI_NONE = 0, + Q_REQUEUE_PI_IGNORE, + Q_REQUEUE_PI_IN_PROGRESS, + Q_REQUEUE_PI_WAIT, + Q_REQUEUE_PI_DONE, + Q_REQUEUE_PI_LOCKED, +}; + +static const struct futex_q futex_q_init = { + /* list gets initialized in queue_me()*/ + .key = FUTEX_KEY_INIT, + .bitset = FUTEX_BITSET_MATCH_ANY, + .requeue_state = ATOMIC_INIT(Q_REQUEUE_PI_NONE), +}; + +inline struct hrtimer_sleeper * +futex_setup_timer(ktime_t *time, struct hrtimer_sleeper *timeout, + int flags, u64 range_ns); + +static __always_inline int +futex_init_timeout(u32 cmd, u32 op, struct timespec64 *ts, ktime_t *t) +{ + if (!timespec64_valid(ts)) + return -EINVAL; + + *t = timespec64_to_ktime(*ts); + if (cmd == FUTEX_WAIT) + *t = ktime_add_safe(ktime_get(), *t); + else if (cmd != FUTEX_LOCK_PI && !(op & FUTEX_CLOCK_REALTIME)) + *t = timens_ktime_to_host(CLOCK_MONOTONIC, *t); + return 0; +} + +#endif From patchwork Mon Sep 13 17:52:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Andr=C3=A9_Almeida?= X-Patchwork-Id: 44955 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 52EB23857C47 for ; Mon, 13 Sep 2021 17:55:35 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 52EB23857C47 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1631555735; bh=jYFlWPd8mBHr7ldYqZLj6CISEBVUdCiTPsAKe/zmkT4=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=b5XMfa/TYC9PQkpS9NNaOyBGZUfZf9nMGyzZXoAMXcyNrXCMC0M4Y7wN0uCgui00p JwOpTkrXTBOuFdDUGKcXt1YytX5V3Rx/DpBmLrwOyt9vX+5q0j+8puzT+e/IX0f6oA bq/n3cG88blGQovu/m8pWbiGO3aU3/6CMJHj9lJU= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by sourceware.org (Postfix) with ESMTPS id 310C3385801D for ; Mon, 13 Sep 2021 17:53:14 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 310C3385801D Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: tonyk) with ESMTPSA id 40B871F42D0C To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart , linux-kernel@vger.kernel.org, Steven Rostedt , Sebastian Andrzej Siewior Subject: [PATCH v3 2/6] futex2: Implement vectorized wait Date: Mon, 13 Sep 2021 14:52:45 -0300 Message-Id: <20210913175249.81074-3-andrealmeid@collabora.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210913175249.81074-1-andrealmeid@collabora.com> References: <20210913175249.81074-1-andrealmeid@collabora.com> MIME-Version: 1.0 X-Spam-Status: No, score=-12.1 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_MANYTO, SPF_HELO_PASS, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: =?utf-8?q?Andr=C3=A9_Almeida_via_Libc-alpha?= From: =?utf-8?q?Andr=C3=A9_Almeida?= Reply-To: =?utf-8?q?Andr=C3=A9_Almeida?= Cc: Davidlohr Bueso , libc-alpha@sourceware.org, linux-api@vger.kernel.org, mtk.manpages@gmail.com, =?utf-8?q?Andr=C3=A9_Alm?= =?utf-8?q?eida?= , kernel@collabora.com, krisman@collabora.com Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Add support to wait on multiple futexes. This is the interface implemented by this syscall: futex_waitv(struct futex_waitv *waiters, unsigned int nr_futexes, unsigned int flags, struct timespec *timo) struct futex_waitv { __u64 val; __u64 uaddr; __u32 flags; __u32 __reserved; }; Given an array of struct futex_waitv, wait on each uaddr. The thread wakes if a futex_wake() is performed at any uaddr. The syscall returns immediately if any waiter has *uaddr != val. *timo is an optional absolute timeout value for the operation. This syscall supports only 64bit sized timeout structs. The flags argument of the syscall should be used solely for specifying the timeout clock as realtime, if needed. Flags for shared futexes, sizes, etc. should be used on the individual flags of each waiter. __reserved is used for explicit padding and should be 0, but it might be used for future extensions. If the userspace uses 32-bit pointers, it should make sure to explicitly cast it when assigning to waitv::uaddr. Returns the array index of one of the awakened futexes. There’s no given information of how many were awakened, or any particular attribute of it (if it’s the first awakened, if it is of the smaller index...). Signed-off-by: André Almeida --- MAINTAINERS | 3 +- include/linux/syscalls.h | 6 + include/uapi/asm-generic/unistd.h | 5 +- include/uapi/linux/futex.h | 25 ++++ init/Kconfig | 7 ++ kernel/Makefile | 1 + kernel/futex.c | 201 ++++++++++++++++++++++++++++++ kernel/futex.h | 15 +++ kernel/futex2.c | 117 +++++++++++++++++ kernel/sys_ni.c | 3 + 10 files changed, 381 insertions(+), 2 deletions(-) create mode 100644 kernel/futex2.c diff --git a/MAINTAINERS b/MAINTAINERS index eeb4c70b3d5b..7b756d96f09f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7718,6 +7718,7 @@ M: Ingo Molnar R: Peter Zijlstra R: Darren Hart R: Davidlohr Bueso +R: André Almeida L: linux-kernel@vger.kernel.org S: Maintained T: git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking/core @@ -7725,7 +7726,7 @@ F: Documentation/locking/*futex* F: include/asm-generic/futex.h F: include/linux/futex.h F: include/uapi/linux/futex.h -F: kernel/futex.c +F: kernel/futex* F: tools/perf/bench/futex* F: tools/testing/selftests/futex/ diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 252243c7783d..a30083ec4bd5 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -58,6 +58,7 @@ struct mq_attr; struct compat_stat; struct old_timeval32; struct robust_list_head; +struct futex_waitv; struct getcpu_cache; struct old_linux_dirent; struct perf_event_attr; @@ -623,6 +624,11 @@ asmlinkage long sys_get_robust_list(int pid, asmlinkage long sys_set_robust_list(struct robust_list_head __user *head, size_t len); +/* kernel/futex2.c */ +asmlinkage long sys_futex_waitv(struct futex_waitv *waiters, + unsigned int nr_futexes, unsigned int flags, + struct __kernel_timespec __user *timo); + /* kernel/hrtimer.c */ asmlinkage long sys_nanosleep(struct __kernel_timespec __user *rqtp, struct __kernel_timespec __user *rmtp); diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 1c5fb86d455a..ebafbb27cc41 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -880,8 +880,11 @@ __SYSCALL(__NR_memfd_secret, sys_memfd_secret) #define __NR_process_mrelease 448 __SYSCALL(__NR_process_mrelease, sys_process_mrelease) +#define __NR_futex_waitv 449 +__SC_COMP(__NR_futex_waitv, sys_futex_waitv) + #undef __NR_syscalls -#define __NR_syscalls 449 +#define __NR_syscalls 450 /* * 32 bit systems traditionally used different diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h index 235e5b2facaa..71a5df8d2689 100644 --- a/include/uapi/linux/futex.h +++ b/include/uapi/linux/futex.h @@ -43,6 +43,31 @@ #define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \ FUTEX_PRIVATE_FLAG) +/* + * Flags to specify the bit length of the futex word for futex2 syscalls. + * Currently, only 32 is supported. + */ +#define FUTEX_32 2 + +/* + * Max numbers of elements in a futex_waitv array + */ +#define FUTEX_WAITV_MAX 128 + +/** + * struct futex_waitv - A waiter for vectorized wait + * @val: Expected value at uaddr + * @uaddr: User address to wait on + * @flags: Flags for this waiter + * @__reserved: Reserved member to preserve data alignment. Should be 0. + */ +struct futex_waitv { + __u64 val; + __u64 uaddr; + __u32 flags; + __u32 __reserved; +}; + /* * Support for robust futexes: the kernel cleans up held futexes at * thread exit time. diff --git a/init/Kconfig b/init/Kconfig index 11f8a845f259..a5c9300f9000 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1581,6 +1581,13 @@ config FUTEX support for "fast userspace mutexes". The resulting kernel may not run glibc-based applications correctly. +config FUTEX2 + bool "Enable futex2 support" if EXPERT + depends on FUTEX + default y + help + Support for futex2 interface. + config FUTEX_PI bool depends on FUTEX && RT_MUTEXES diff --git a/kernel/Makefile b/kernel/Makefile index 4df609be42d0..1eaf2af50283 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -60,6 +60,7 @@ obj-$(CONFIG_PROFILING) += profile.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-y += time/ obj-$(CONFIG_FUTEX) += futex.o +obj-$(CONFIG_FUTEX2) += futex2.o obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o obj-$(CONFIG_SMP) += smp.o ifneq ($(CONFIG_SMP),y) diff --git a/kernel/futex.c b/kernel/futex.c index 32c91f9d7385..858465f97d9b 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2739,6 +2739,207 @@ static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q, __set_current_state(TASK_RUNNING); } +/** + * unqueue_multiple - Remove various futexes from their hash bucket + * @v: 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 - No futex was awoken + */ +static int unqueue_multiple(struct futex_vector *v, int count) +{ + int ret = -1, i; + + for (i = 0; i < count; i++) { + if (!unqueue_me(&v[i].q)) + ret = i; + } + + return ret; +} + +/** + * futex_wait_multiple_setup - Prepare to wait and enqueue multiple futexes + * @vs: The futex list to wait on + * @count: The size of the list + * @awaken: Index of the last awoken futex, if any. Used to notify the + * caller that it can return this index to userspace (return parameter) + * + * 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_vector *vs, int count, int *awaken) +{ + struct futex_hash_bucket *hb; + bool retry = false; + 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. + * + * Private futexes doesn't need to recalculate hash in retry, so skip + * get_futex_key() when retrying. + */ +retry: + for (i = 0; i < count; i++) { + if ((vs[i].w.flags & FUTEX_PRIVATE_FLAG) && retry) + continue; + + ret = get_futex_key(u64_to_user_ptr(vs[i].w.uaddr), + !(vs[i].w.flags & FUTEX_PRIVATE_FLAG), + &vs[i].q.key, FUTEX_READ); + + if (unlikely(ret)) + return ret; + } + + set_current_state(TASK_INTERRUPTIBLE); + + for (i = 0; i < count; i++) { + u32 __user *uaddr = (u32 __user *)vs[i].w.uaddr; + struct futex_q *q = &vs[i].q; + u32 val = (u32)vs[i].w.val; + + hb = queue_lock(q); + ret = get_futex_value_locked(&uval, uaddr); + + if (!ret && uval == val) { + /* + * 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(q, hb); + continue; + } + + queue_unlock(hb); + __set_current_state(TASK_RUNNING); + + /* + * Even if something went wrong, if we find out that a futex + * was awaken, we don't return error and return this index to + * userspace + */ + *awaken = unqueue_multiple(vs, i); + if (*awaken >= 0) + return 1; + + if (uval != val) + return -EWOULDBLOCK; + + if (ret) { + /* + * If we need to handle a page fault, we need to do so + * without any lock and any enqueued futex (otherwise + * we could lose some wakeup). So we do it here, after + * undoing all the work done so far. In success, we + * retry all the work. + */ + if (get_user(uval, uaddr)) + return -EFAULT; + + retry = true; + goto retry; + } + } + + return 0; +} + +/** + * futex_sleep_multiple - Check sleeping conditions and sleep + * @vs: List of futexes to wait for + * @count: Length of vs + * @to: Timeout + * + * Sleep if and only if the timeout hasn't expired and no futex on the list has + * been awaken. + */ +static void futex_sleep_multiple(struct futex_vector *vs, unsigned int count, + struct hrtimer_sleeper *to) +{ + if (to && !to->task) + return; + + for (; count; count--, vs++) { + if (!READ_ONCE(vs->q.lock_ptr)) + return; + } + + freezable_schedule(); +} + +/** + * futex_wait_multiple - Prepare to wait on and enqueue several futexes + * @vs: The list of futexes to wait on + * @count: The number of objects + * @to: 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 is + * wake, or after the timeout has elapsed. + * + * Return: + * - >=0 - Hint to the futex that was awoken + * - <0 - On error + */ +int futex_wait_multiple(struct futex_vector *vs, unsigned int count, + struct hrtimer_sleeper *to) +{ + int ret, hint = 0; + + if (to) + hrtimer_sleeper_start_expires(to, HRTIMER_MODE_ABS); + + while (1) { + ret = futex_wait_multiple_setup(vs, count, &hint); + if (ret) { + if (ret > 0) { + /* A futex was awaken during setup */ + ret = hint; + } + return ret; + } + + futex_sleep_multiple(vs, count, to); + + __set_current_state(TASK_RUNNING); + + ret = unqueue_multiple(vs, count); + if (ret >= 0) + return ret; + + if (to && !to->task) + return -ETIMEDOUT; + else if (signal_pending(current)) + return -ERESTARTSYS; + /* + * The final case is a spurious wakeup, for + * which just retry. + */ + } +} + /** * futex_wait_setup() - Prepare to wait on a futex * @uaddr: the futex userspace address diff --git a/kernel/futex.h b/kernel/futex.h index c914e0080cf1..bcd0142c3f6e 100644 --- a/kernel/futex.h +++ b/kernel/futex.h @@ -137,4 +137,19 @@ futex_init_timeout(u32 cmd, u32 op, struct timespec64 *ts, ktime_t *t) return 0; } +/** + * struct futex_vector - Auxiliary struct for futex_waitv() + * @w: Userspace provided data + * @q: Kernel side data + * + * Struct used to build an array with all data need for futex_waitv() + */ +struct futex_vector { + struct futex_waitv w; + struct futex_q q; +}; + +int futex_wait_multiple(struct futex_vector *vs, unsigned int count, + struct hrtimer_sleeper *to); + #endif diff --git a/kernel/futex2.c b/kernel/futex2.c new file mode 100644 index 000000000000..f724ecf40f3e --- /dev/null +++ b/kernel/futex2.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * futex2 interface system calls + * + * futex_waitv by André Almeida + * + * Copyright 2021 Collabora Ltd. + */ + +#include "futex.h" + +/* Mask of available flags for each futex in futex_waitv list */ +#define FUTEXV_WAITER_MASK (FUTEX_32 | FUTEX_PRIVATE_FLAG) + +/* Mask of available flags for sys_futex_waitv flag */ +#define FUTEXV_MASK (FUTEX_CLOCK_REALTIME) + +/** + * futex_parse_waitv - Parse a waitv array from userspace + * @futexv: Kernel side list of waiters to be filled + * @uwaitv: Userspace list to be parsed + * @nr_futexes: Length of futexv + * + * Return: Error code on failure, 0 on success + */ +static int futex_parse_waitv(struct futex_vector *futexv, + struct futex_waitv __user *uwaitv, + unsigned int nr_futexes) +{ + struct futex_waitv aux; + unsigned int i; + + for (i = 0; i < nr_futexes; i++) { + if (copy_from_user(&aux, &uwaitv[i], sizeof(aux))) + return -EFAULT; + + if ((aux.flags & ~FUTEXV_WAITER_MASK) || aux.__reserved) + return -EINVAL; + + futexv[i].w.flags = aux.flags; + futexv[i].w.val = aux.val; + futexv[i].w.uaddr = aux.uaddr; + futexv[i].q = futex_q_init; + } + + return 0; +} + +/** + * sys_futex_waitv - Wait on a list of futexes + * @waiters: List of futexes to wait on + * @nr_futexes: Length of futexv + * @flags: Flag for timeout (monotonic/realtime) + * @timo: Optional absolute timeout. + * + * Given an array of `struct futex_waitv`, wait on each uaddr. The thread wakes + * if a futex_wake() is performed at any uaddr. The syscall returns immediately + * if any waiter has *uaddr != val. *timo is an optional timeout value for the + * operation. Each waiter has individual flags. The `flags` argument for the + * syscall should be used solely for specifying the timeout as realtime, if + * needed. Flags for shared futexes, sizes, etc. should be used on the + * individual flags of each waiter. + * + * Returns the array index of one of the awaken futexes. There's no given + * information of how many were awakened, or any particular attribute of it (if + * it's the first awakened, if it is of the smaller index...). + */ + +SYSCALL_DEFINE4(futex_waitv, struct futex_waitv __user *, waiters, + unsigned int, nr_futexes, unsigned int, flags, + struct __kernel_timespec __user *, timo) +{ + struct hrtimer_sleeper to; + struct futex_vector *futexv; + struct timespec64 ts; + ktime_t time; + int ret; + + if (flags & ~FUTEXV_MASK) + return -EINVAL; + + if (!nr_futexes || nr_futexes > FUTEX_WAITV_MAX || !waiters) + return -EINVAL; + + if (timo) { + int flag_clkid = (flags & FUTEX_CLOCK_REALTIME) ? FLAGS_CLOCKRT : 0; + + if (get_timespec64(&ts, timo)) + return -EFAULT; + + /* + * Since there's no opcode for futex_waitv, use + * FUTEX_WAIT_BITSET that uses absolute timeout as well + */ + ret = futex_init_timeout(FUTEX_WAIT_BITSET, flags, &ts, &time); + if (ret) + return ret; + + futex_setup_timer(&time, &to, flag_clkid, 0); + } + + futexv = kcalloc(nr_futexes, sizeof(*futexv), GFP_KERNEL); + if (!futexv) + return -ENOMEM; + + ret = futex_parse_waitv(futexv, waiters, nr_futexes); + if (!ret) + ret = futex_wait_multiple(futexv, nr_futexes, timo ? &to : NULL); + + if (timo) { + hrtimer_cancel(&to.timer); + destroy_hrtimer_on_stack(&to.timer); + } + + kfree(futexv); + return ret; +} diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index f43d89d92860..3d0b94f6b88d 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -151,6 +151,9 @@ COND_SYSCALL_COMPAT(set_robust_list); COND_SYSCALL(get_robust_list); COND_SYSCALL_COMPAT(get_robust_list); +/* kernel/futex2.c */ +COND_SYSCALL(futex_waitv); + /* kernel/hrtimer.c */ /* kernel/itimer.c */ From patchwork Mon Sep 13 17:52:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Andr=C3=A9_Almeida?= X-Patchwork-Id: 44956 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 6308D385843B for ; Mon, 13 Sep 2021 17:56:17 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 6308D385843B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1631555777; bh=AQmKgfH3qEqOtDyuCan45GTszTZszAW9eky6Y41uuFc=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=bVauukyclBiqMMIdHHzeE/RrQSAs2VvR4VXJqWQDNfL7c61kSOTuWBmAHo5qk8CKh jl6FFoqwj+8UCsp77TpmirUsoUgMwINwHlNvZGKCGoXt1add4V+we/pfGnfzlPk7ki FLc7ZMimuF27CCnNo7CrYPuCzxZ+cGGUq7GGw6ls= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by sourceware.org (Postfix) with ESMTPS id 851E33858026 for ; Mon, 13 Sep 2021 17:53:18 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 851E33858026 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: tonyk) with ESMTPSA id DA46C1F42D19 To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart , linux-kernel@vger.kernel.org, Steven Rostedt , Sebastian Andrzej Siewior Subject: [PATCH v3 3/6] futex2: wire up syscall for x86 Date: Mon, 13 Sep 2021 14:52:46 -0300 Message-Id: <20210913175249.81074-4-andrealmeid@collabora.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210913175249.81074-1-andrealmeid@collabora.com> References: <20210913175249.81074-1-andrealmeid@collabora.com> MIME-Version: 1.0 X-Spam-Status: No, score=-11.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_MANYTO, KAM_NUMSUBJECT, SPF_HELO_PASS, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: =?utf-8?q?Andr=C3=A9_Almeida_via_Libc-alpha?= From: =?utf-8?q?Andr=C3=A9_Almeida?= Reply-To: =?utf-8?q?Andr=C3=A9_Almeida?= Cc: Davidlohr Bueso , libc-alpha@sourceware.org, linux-api@vger.kernel.org, mtk.manpages@gmail.com, =?utf-8?q?Andr=C3=A9_Alm?= =?utf-8?q?eida?= , kernel@collabora.com, krisman@collabora.com Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Wire up syscall entry point for x86 arch, for both i386 and x86_64. Signed-off-by: André Almeida --- arch/x86/entry/syscalls/syscall_32.tbl | 1 + arch/x86/entry/syscalls/syscall_64.tbl | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index 960a021d543e..7e25543693de 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -453,3 +453,4 @@ 446 i386 landlock_restrict_self sys_landlock_restrict_self 447 i386 memfd_secret sys_memfd_secret 448 i386 process_mrelease sys_process_mrelease +449 i386 futex_waitv sys_futex_waitv diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 18b5500ea8bf..fe8f8dd157b4 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -370,6 +370,7 @@ 446 common landlock_restrict_self sys_landlock_restrict_self 447 common memfd_secret sys_memfd_secret 448 common process_mrelease sys_process_mrelease +449 common futex_waitv sys_futex_waitv # # Due to a historical design error, certain syscalls are numbered differently From patchwork Mon Sep 13 17:52:47 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Andr=C3=A9_Almeida?= X-Patchwork-Id: 44957 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 6146F3858026 for ; Mon, 13 Sep 2021 17:57:56 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 6146F3858026 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1631555876; bh=TcUgeK1f7MYUTxeE4wkOszpYbkRNjGhnupZq43vQbJI=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=HSPNJx0Z4FphZ7rl/35JclgG9p6AKUZ54sySxAfKvbAj6Gx6LNx5aJgnqrHEQNVX2 BAESvhnpiBxfB2uS6wtjznNWBqqcGAIhn6+UgaKNXKxqO6HI/yk7gmJQQbXCCNiowj 1j+RyV/3c9lCv1EXVrxlMn/0ieFGyGrnGUmFBkVQ= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by sourceware.org (Postfix) with ESMTPS id AF4B7385842C for ; Mon, 13 Sep 2021 17:53:22 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org AF4B7385842C Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: tonyk) with ESMTPSA id 3B8AE1F42D21 To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart , linux-kernel@vger.kernel.org, Steven Rostedt , Sebastian Andrzej Siewior Subject: [PATCH v3 4/6] futex2: wire up syscall for ARM Date: Mon, 13 Sep 2021 14:52:47 -0300 Message-Id: <20210913175249.81074-5-andrealmeid@collabora.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210913175249.81074-1-andrealmeid@collabora.com> References: <20210913175249.81074-1-andrealmeid@collabora.com> MIME-Version: 1.0 X-Spam-Status: No, score=-12.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_MANYTO, SPF_HELO_PASS, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: =?utf-8?q?Andr=C3=A9_Almeida_via_Libc-alpha?= From: =?utf-8?q?Andr=C3=A9_Almeida?= Reply-To: =?utf-8?q?Andr=C3=A9_Almeida?= Cc: Davidlohr Bueso , libc-alpha@sourceware.org, linux-api@vger.kernel.org, mtk.manpages@gmail.com, =?utf-8?q?Andr=C3=A9_Alm?= =?utf-8?q?eida?= , kernel@collabora.com, krisman@collabora.com Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Wire up syscall entry point for ARM architectures, for both 32 and 64-bit. Signed-off-by: André Almeida --- arch/arm/tools/syscall.tbl | 1 + arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 2 ++ 3 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index e842209e135d..543100151f2b 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -462,3 +462,4 @@ 446 common landlock_restrict_self sys_landlock_restrict_self # 447 reserved for memfd_secret 448 common process_mrelease sys_process_mrelease +449 common futex_waitv sys_futex_waitv diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h index 3cb206aea3db..6bdb5f5db438 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -38,7 +38,7 @@ #define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5) #define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800) -#define __NR_compat_syscalls 449 +#define __NR_compat_syscalls 450 #endif #define __ARCH_WANT_SYS_CLONE diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h index 844f6ae58662..41ea1195e44b 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -903,6 +903,8 @@ __SYSCALL(__NR_landlock_add_rule, sys_landlock_add_rule) __SYSCALL(__NR_landlock_restrict_self, sys_landlock_restrict_self) #define __NR_process_mrelease 448 __SYSCALL(__NR_process_mrelease, sys_process_mrelease) +#define __NR_futex_waitv 449 +__SYSCALL(__NR_futex_waitv, sys_futex_waitv) /* * Please add new compat syscalls above this comment and update From patchwork Mon Sep 13 17:52:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Andr=C3=A9_Almeida?= X-Patchwork-Id: 44958 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 8737C385801D for ; Mon, 13 Sep 2021 17:58:38 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 8737C385801D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1631555918; bh=X702utzC/Jz5tYVNNsk6XSXgQwncmG5+qNFNFp9SZ6Q=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=xaaa/mwO+Ykmm3EmSwfLWgU806VBtke8U+nXNYuFr5B9/YPqYHPFZEBsdcoQHvThD GFPbSvmjR1wixAvLeCD5Psy9b0oX5nwv/6aKJz+SwHjYClsjzQGblPXG/lo4RoqhUK sAvnX0xBw8ns1tno1aOYUBrr0AwNqy5BX8VELRRo= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by sourceware.org (Postfix) with ESMTPS id E7D133857C47 for ; Mon, 13 Sep 2021 17:53:26 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org E7D133857C47 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: tonyk) with ESMTPSA id 7300A1F42D0A To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart , linux-kernel@vger.kernel.org, Steven Rostedt , Sebastian Andrzej Siewior Subject: [PATCH v3 5/6] selftests: futex2: Add waitv test Date: Mon, 13 Sep 2021 14:52:48 -0300 Message-Id: <20210913175249.81074-6-andrealmeid@collabora.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210913175249.81074-1-andrealmeid@collabora.com> References: <20210913175249.81074-1-andrealmeid@collabora.com> MIME-Version: 1.0 X-Spam-Status: No, score=-12.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_MANYTO, SPF_HELO_PASS, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: =?utf-8?q?Andr=C3=A9_Almeida_via_Libc-alpha?= From: =?utf-8?q?Andr=C3=A9_Almeida?= Reply-To: =?utf-8?q?Andr=C3=A9_Almeida?= Cc: Davidlohr Bueso , libc-alpha@sourceware.org, linux-api@vger.kernel.org, mtk.manpages@gmail.com, =?utf-8?q?Andr=C3=A9_Alm?= =?utf-8?q?eida?= , kernel@collabora.com, krisman@collabora.com Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Create a new file to test the waitv mechanism. Test both private and shared futexes. Wake the last futex in the array, and check if the return value from futex_waitv() is the right index. Signed-off-by: André Almeida --- .../selftests/futex/functional/.gitignore | 1 + .../selftests/futex/functional/Makefile | 3 +- .../selftests/futex/functional/futex_waitv.c | 158 ++++++++++++++++++ .../testing/selftests/futex/functional/run.sh | 3 + .../selftests/futex/include/futex2test.h | 31 ++++ 5 files changed, 195 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/futex/functional/futex_waitv.c create mode 100644 tools/testing/selftests/futex/include/futex2test.h diff --git a/tools/testing/selftests/futex/functional/.gitignore b/tools/testing/selftests/futex/functional/.gitignore index 0e78b49d0f2f..fbcbdb6963b3 100644 --- a/tools/testing/selftests/futex/functional/.gitignore +++ b/tools/testing/selftests/futex/functional/.gitignore @@ -8,3 +8,4 @@ futex_wait_uninitialized_heap futex_wait_wouldblock futex_wait futex_requeue +futex_waitv diff --git a/tools/testing/selftests/futex/functional/Makefile b/tools/testing/selftests/futex/functional/Makefile index bd1fec59e010..5cc38de9d8ea 100644 --- a/tools/testing/selftests/futex/functional/Makefile +++ b/tools/testing/selftests/futex/functional/Makefile @@ -17,7 +17,8 @@ TEST_GEN_FILES := \ futex_wait_uninitialized_heap \ futex_wait_private_mapped_file \ futex_wait \ - futex_requeue + futex_requeue \ + futex_waitv TEST_PROGS := run.sh diff --git a/tools/testing/selftests/futex/functional/futex_waitv.c b/tools/testing/selftests/futex/functional/futex_waitv.c new file mode 100644 index 000000000000..567667dfa7cf --- /dev/null +++ b/tools/testing/selftests/futex/functional/futex_waitv.c @@ -0,0 +1,158 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/****************************************************************************** + * + * Copyright Collabora Ltd., 2021 + * + * DESCRIPTION + * Test waitv/wake mechanism of futex2, using 32bit sized futexes. + * + * AUTHOR + * André Almeida + * + * HISTORY + * 2021-Feb-5: Initial version by André + * + *****************************************************************************/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "futextest.h" +#include "futex2test.h" +#include "logging.h" + +#define TEST_NAME "futex-wait" +#define WAKE_WAIT_US 10000 +#define NR_FUTEXES 30 +static struct futex_waitv waitv[NR_FUTEXES]; +u_int32_t futexes[NR_FUTEXES] = {0}; + +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 *waiterfn(void *arg) +{ + struct timespec to; + int res; + + /* setting absolute timeout for futex2 */ + if (clock_gettime(CLOCK_MONOTONIC, &to)) + error("gettime64 failed\n", errno); + + to.tv_sec++; + + res = futex_waitv(waitv, NR_FUTEXES, 0, &to); + if (res < 0) { + ksft_test_result_fail("futex_waitv returned: %d %s\n", + errno, strerror(errno)); + } else if (res != NR_FUTEXES - 1) { + ksft_test_result_fail("futex_waitv returned: %d, expecting %d\n", + res, NR_FUTEXES - 1); + } + + return NULL; +} + +int main(int argc, char *argv[]) +{ + pthread_t waiter; + int res, ret = RET_PASS; + int c, i; + + 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); + } + } + + ksft_print_header(); + ksft_set_plan(2); + ksft_print_msg("%s: Test FUTEX_WAITV\n", + basename(argv[0])); + + for (i = 0; i < NR_FUTEXES; i++) { + waitv[i].uaddr = (uintptr_t)&futexes[i]; + waitv[i].flags = FUTEX_32 | FUTEX_PRIVATE_FLAG; + waitv[i].val = 0; + waitv[i].__reserved = 0; + } + + /* Private waitv */ + if (pthread_create(&waiter, NULL, waiterfn, NULL)) + error("pthread_create failed\n", errno); + + usleep(WAKE_WAIT_US); + + res = futex_wake(u64_to_ptr(waitv[NR_FUTEXES - 1].uaddr), 1, FUTEX_PRIVATE_FLAG); + if (res != 1) { + ksft_test_result_fail("futex_wake private returned: %d %s\n", + res ? errno : res, + res ? strerror(errno) : ""); + ret = RET_FAIL; + } else { + ksft_test_result_pass("futex_waitv private\n"); + } + + /* Shared waitv */ + for (i = 0; i < NR_FUTEXES; i++) { + int shm_id = shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666); + + if (shm_id < 0) { + perror("shmget"); + exit(1); + } + + unsigned int *shared_data = shmat(shm_id, NULL, 0); + + *shared_data = 0; + waitv[i].uaddr = (uintptr_t)shared_data; + waitv[i].flags = FUTEX_32; + waitv[i].val = 0; + waitv[i].__reserved = 0; + } + + if (pthread_create(&waiter, NULL, waiterfn, NULL)) + error("pthread_create failed\n", errno); + + usleep(WAKE_WAIT_US); + + res = futex_wake(u64_to_ptr(waitv[NR_FUTEXES - 1].uaddr), 1, 0); + if (res != 1) { + ksft_test_result_fail("futex_wake shared returned: %d %s\n", + res ? errno : res, + res ? strerror(errno) : ""); + ret = RET_FAIL; + } else { + ksft_test_result_pass("futex_waitv shared\n"); + } + + for (i = 0; i < NR_FUTEXES; i++) + shmdt(u64_to_ptr(waitv[i].uaddr)); + + ksft_print_cnts(); + return ret; +} diff --git a/tools/testing/selftests/futex/functional/run.sh b/tools/testing/selftests/futex/functional/run.sh index 11a9d62290f5..5ccd599da6c3 100755 --- a/tools/testing/selftests/futex/functional/run.sh +++ b/tools/testing/selftests/futex/functional/run.sh @@ -79,3 +79,6 @@ echo echo ./futex_requeue $COLOR + +echo +./futex_waitv $COLOR diff --git a/tools/testing/selftests/futex/include/futex2test.h b/tools/testing/selftests/futex/include/futex2test.h new file mode 100644 index 000000000000..51a3b9356c9b --- /dev/null +++ b/tools/testing/selftests/futex/include/futex2test.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/****************************************************************************** + * + * Copyright Collabora Ltd., 2021 + * + * DESCRIPTION + * Futex2 library addons for futex tests + * + * AUTHOR + * André Almeida + * + * HISTORY + * 2021-Feb-5: Initial version by André + * + *****************************************************************************/ +#include + +#define u64_to_ptr(x) ((void *)(uintptr_t)(x)) + +/** + * futex_waitv - Wait at multiple futexes, wake on any + * @waiters: Array of waiters + * @nr_waiters: Length of waiters array + * @flags: Operation flags + * @timo: Optional timeout for operation + */ +static inline int futex_waitv(volatile struct futex_waitv *waiters, unsigned long nr_waiters, + unsigned long flags, struct timespec *timo) +{ + return syscall(__NR_futex_waitv, waiters, nr_waiters, flags, timo); +} From patchwork Mon Sep 13 17:52:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Andr=C3=A9_Almeida?= X-Patchwork-Id: 44959 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 319BC3858039 for ; Mon, 13 Sep 2021 17:59:28 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 319BC3858039 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1631555968; bh=YbEz7hbR0vUTJcANoy2TUU8aIBHuxfll14EJQRAOdbQ=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=MFj9W9KAGjuVHim1YnA2OBIzIOOprInL5yYbyzQ5ZkILX9u0/ypASjV8t9dzddWX/ HAFj7sE2D9cSoPy265VPQp7SHPJhgKAALFgX0dRIZIWHQNe3xK2t8B91rn+8fn+3rN iwTTSEs5yD8oglqJmj81nFycNzSqu5UqLnXGB0Rk= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by sourceware.org (Postfix) with ESMTPS id 2E8CD385802D for ; Mon, 13 Sep 2021 17:53:31 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 2E8CD385802D Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: tonyk) with ESMTPSA id AF3991F42D02 To: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart , linux-kernel@vger.kernel.org, Steven Rostedt , Sebastian Andrzej Siewior Subject: [PATCH v3 6/6] selftests: futex2: Test futex_waitv timeout Date: Mon, 13 Sep 2021 14:52:49 -0300 Message-Id: <20210913175249.81074-7-andrealmeid@collabora.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210913175249.81074-1-andrealmeid@collabora.com> References: <20210913175249.81074-1-andrealmeid@collabora.com> MIME-Version: 1.0 X-Spam-Status: No, score=-12.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, KAM_MANYTO, SPF_HELO_PASS, SPF_PASS, TXREP, UNPARSEABLE_RELAY autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: =?utf-8?q?Andr=C3=A9_Almeida_via_Libc-alpha?= From: =?utf-8?q?Andr=C3=A9_Almeida?= Reply-To: =?utf-8?q?Andr=C3=A9_Almeida?= Cc: Davidlohr Bueso , libc-alpha@sourceware.org, linux-api@vger.kernel.org, mtk.manpages@gmail.com, =?utf-8?q?Andr=C3=A9_Alm?= =?utf-8?q?eida?= , kernel@collabora.com, krisman@collabora.com Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" Test if the futex_waitv timeout is working as expected, using the supported clockid options. Signed-off-by: André Almeida --- .../futex/functional/futex_wait_timeout.c | 21 ++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/futex/functional/futex_wait_timeout.c b/tools/testing/selftests/futex/functional/futex_wait_timeout.c index 1f8f6daaf1e7..4cdada0fcb81 100644 --- a/tools/testing/selftests/futex/functional/futex_wait_timeout.c +++ b/tools/testing/selftests/futex/functional/futex_wait_timeout.c @@ -17,6 +17,7 @@ #include #include "futextest.h" +#include "futex2test.h" #include "logging.h" #define TEST_NAME "futex-wait-timeout" @@ -96,6 +97,12 @@ int main(int argc, char *argv[]) struct timespec to; pthread_t thread; int c; + struct futex_waitv waitv = { + .uaddr = (uintptr_t)&f1, + .val = f1, + .flags = FUTEX_32, + .__reserved = 0 + }; while ((c = getopt(argc, argv, "cht:v:")) != -1) { switch (c) { @@ -118,7 +125,7 @@ int main(int argc, char *argv[]) } ksft_print_header(); - ksft_set_plan(7); + ksft_set_plan(9); 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); @@ -175,6 +182,18 @@ int main(int argc, char *argv[]) res = futex_lock_pi(&futex_pi, NULL, 0, FUTEX_CLOCK_REALTIME); test_timeout(res, &ret, "futex_lock_pi invalid timeout flag", ENOSYS); + /* futex_waitv with CLOCK_MONOTONIC */ + if (futex_get_abs_timeout(CLOCK_MONOTONIC, &to, timeout_ns)) + return RET_FAIL; + res = futex_waitv(&waitv, 1, 0, &to); + test_timeout(res, &ret, "futex_waitv monotonic", ETIMEDOUT); + + /* futex_waitv with CLOCK_REALTIME */ + if (futex_get_abs_timeout(CLOCK_REALTIME, &to, timeout_ns)) + return RET_FAIL; + res = futex_waitv(&waitv, 1, FUTEX_CLOCK_REALTIME, &to); + test_timeout(res, &ret, "futex_waitv realtime", ETIMEDOUT); + ksft_print_cnts(); return ret; }