From nobody Fri Feb 13 17:34:09 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 995C8E7D0A4 for ; Thu, 21 Sep 2023 19:02:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230013AbjIUTCY (ORCPT ); Thu, 21 Sep 2023 15:02:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42682 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229905AbjIUTCH (ORCPT ); Thu, 21 Sep 2023 15:02:07 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36DCE7E4CC; Thu, 21 Sep 2023 10:36:02 -0700 (PDT) Date: Thu, 21 Sep 2023 17:35:59 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1695317760; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uC12/rilTZVClOtuhAIBo3hgsDJyZhHceNPIIAVhvMs=; b=TLGGKmWQdrpCpBwXnOw62mkudakedMYR2qcrCWAu+OGos/uWgTpShnrn+ChpaM8lbOxOsV aJG6mQ6nvsAK65jrVqpJHX+3+z/06U8RREUzJuIjsYWZnVd3y1hLOEjTRcFaXBtDVFTiXB Rd4vhjyAK7d5wcR+w8Zs4jOgcgW6FirTmJvHTVUkyB3L83c9T8uQ+tkMHSWgaALY6q2rAh GWSscZu2kYYLEm9lUvr2a/zVmQXlFJ5RC8zqjpzR52b5CbkedWGsz4YI6xsI5nlVPXFsNm bEF/DjBxGzfEg2Y4x/aXYpkKj7i3zayC2I22KvxVj/oPSasybgn7JAvVwd7g0w== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1695317760; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uC12/rilTZVClOtuhAIBo3hgsDJyZhHceNPIIAVhvMs=; b=/OmIrzLu3YzgwhdjS6LKTMTA1B+t9rs7QttWq8JGg25EmQZ0rrHfnRQPGRoNq+uKgf6Q+b OWMmakvh0gq/+FBw== From: "tip-bot2 for peterz@infradead.org" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: locking/core] futex: Add sys_futex_requeue() Cc: "Peter Zijlstra (Intel)" , Thomas Gleixner , Geert Uytterhoeven , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20230921105248.511860556@noisy.programming.kicks-ass.net> References: <20230921105248.511860556@noisy.programming.kicks-ass.net> MIME-Version: 1.0 Message-ID: <169531775974.27769.6116959399118400043.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the locking/core branch of tip: Commit-ID: 0f4b5f972216782a4acb1ae00dcb55173847c2ff Gitweb: https://git.kernel.org/tip/0f4b5f972216782a4acb1ae00dcb55173= 847c2ff Author: peterz@infradead.org AuthorDate: Thu, 21 Sep 2023 12:45:15 +02:00 Committer: Peter Zijlstra CommitterDate: Thu, 21 Sep 2023 19:22:10 +02:00 futex: Add sys_futex_requeue() Finish off the 'simple' futex2 syscall group by adding sys_futex_requeue(). Unlike sys_futex_{wait,wake}() its arguments are too numerous to fit into a regular syscall. As such, use struct futex_waitv to pass the 'source' and 'destination' futexes to the syscall. This syscall implements what was previously known as FUTEX_CMP_REQUEUE and uses {val, uaddr, flags} for source and {uaddr, flags} for destination. This design explicitly allows requeueing between different types of futex by having a different flags word per uaddr. Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Thomas Gleixner Acked-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20230921105248.511860556@noisy.programming.= kicks-ass.net --- arch/alpha/kernel/syscalls/syscall.tbl | 1 +- arch/arm/tools/syscall.tbl | 1 +- arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 2 +- arch/ia64/kernel/syscalls/syscall.tbl | 1 +- arch/m68k/kernel/syscalls/syscall.tbl | 1 +- arch/microblaze/kernel/syscalls/syscall.tbl | 1 +- arch/mips/kernel/syscalls/syscall_n32.tbl | 1 +- arch/mips/kernel/syscalls/syscall_n64.tbl | 1 +- arch/mips/kernel/syscalls/syscall_o32.tbl | 1 +- arch/parisc/kernel/syscalls/syscall.tbl | 1 +- arch/powerpc/kernel/syscalls/syscall.tbl | 1 +- arch/s390/kernel/syscalls/syscall.tbl | 1 +- arch/sh/kernel/syscalls/syscall.tbl | 1 +- arch/sparc/kernel/syscalls/syscall.tbl | 1 +- arch/x86/entry/syscalls/syscall_32.tbl | 1 +- arch/x86/entry/syscalls/syscall_64.tbl | 1 +- arch/xtensa/kernel/syscalls/syscall.tbl | 1 +- include/linux/syscalls.h | 3 ++- include/uapi/asm-generic/unistd.h | 4 +- kernel/futex/syscalls.c | 38 ++++++++++++++++++++- kernel/sys_ni.c | 1 +- 22 files changed, 64 insertions(+), 2 deletions(-) diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/sys= calls/syscall.tbl index c49f12f..b1865f9 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -494,3 +494,4 @@ 562 common fchmodat2 sys_fchmodat2 563 common futex_wake sys_futex_wake 564 common futex_wait sys_futex_wait +565 common futex_requeue sys_futex_requeue diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index a6cf562..93d0d46 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -468,3 +468,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unist= d.h index f33190f..531effc 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -39,7 +39,7 @@ #define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5) #define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800) =20 -#define __NR_compat_syscalls 456 +#define __NR_compat_syscalls 457 #endif =20 #define __ARCH_WANT_SYS_CLONE diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/uni= std32.h index 6e7d372..c453291 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -915,6 +915,8 @@ __SYSCALL(__NR_fchmodat2, sys_fchmodat2) __SYSCALL(__NR_futex_wake, sys_futex_wake) #define __NR_futex_wait 455 __SYSCALL(__NR_futex_wait, sys_futex_wait) +#define __NR_futex_requeue 456 +__SYSCALL(__NR_futex_requeue, sys_futex_requeue) =20 /* * Please add new compat syscalls above this comment and update diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/sysca= lls/syscall.tbl index 4043f0c..81375ea 100644 --- a/arch/ia64/kernel/syscalls/syscall.tbl +++ b/arch/ia64/kernel/syscalls/syscall.tbl @@ -375,3 +375,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/sysca= lls/syscall.tbl index 2484167..f7f997a 100644 --- a/arch/m68k/kernel/syscalls/syscall.tbl +++ b/arch/m68k/kernel/syscalls/syscall.tbl @@ -454,3 +454,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/= kernel/syscalls/syscall.tbl index f03927a..2967ec2 100644 --- a/arch/microblaze/kernel/syscalls/syscall.tbl +++ b/arch/microblaze/kernel/syscalls/syscall.tbl @@ -460,3 +460,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/s= yscalls/syscall_n32.tbl index dbb5edf..383abb1 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -393,3 +393,4 @@ 452 n32 fchmodat2 sys_fchmodat2 454 n32 futex_wake sys_futex_wake 455 n32 futex_wait sys_futex_wait +456 n32 futex_requeue sys_futex_requeue diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/s= yscalls/syscall_n64.tbl index faff8df..c9bd09b 100644 --- a/arch/mips/kernel/syscalls/syscall_n64.tbl +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl @@ -369,3 +369,4 @@ 452 n64 fchmodat2 sys_fchmodat2 454 n64 futex_wake sys_futex_wake 455 n64 futex_wait sys_futex_wait +456 n64 futex_requeue sys_futex_requeue diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/s= yscalls/syscall_o32.tbl index 542f756..ba5ef6c 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -442,3 +442,4 @@ 452 o32 fchmodat2 sys_fchmodat2 454 o32 futex_wake sys_futex_wake 455 o32 futex_wait sys_futex_wait +456 o32 futex_requeue sys_futex_requeue diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/s= yscalls/syscall.tbl index 8e50e89..9f0f6df 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -453,3 +453,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel= /syscalls/syscall.tbl index ad33a99..26fc419 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -541,3 +541,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/sysca= lls/syscall.tbl index 418853f..31be90b 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -457,3 +457,4 @@ 452 common fchmodat2 sys_fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue sys_futex_requeue diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/= syscall.tbl index 8ef9557..4bc5d48 100644 --- a/arch/sh/kernel/syscalls/syscall.tbl +++ b/arch/sh/kernel/syscalls/syscall.tbl @@ -457,3 +457,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/sys= calls/syscall.tbl index df59a9d..8404c8e 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -500,3 +500,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscal= ls/syscall_32.tbl index 0f66168..31c48bc 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -459,3 +459,4 @@ 452 i386 fchmodat2 sys_fchmodat2 454 i386 futex_wake sys_futex_wake 455 i386 futex_wait sys_futex_wait +456 i386 futex_requeue sys_futex_requeue diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscal= ls/syscall_64.tbl index ddf6288..a577bb2 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -377,6 +377,7 @@ 453 64 map_shadow_stack sys_map_shadow_stack 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue =20 # # Due to a historical design error, certain syscalls are numbered differen= tly diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/s= yscalls/syscall.tbl index ac278db..dd71ecc 100644 --- a/arch/xtensa/kernel/syscalls/syscall.tbl +++ b/arch/xtensa/kernel/syscalls/syscall.tbl @@ -425,3 +425,4 @@ 452 common fchmodat2 sys_fchmodat2 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait +456 common futex_requeue sys_futex_requeue diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 11f3fdd..0901af6 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -556,6 +556,9 @@ asmlinkage long sys_futex_wait(void __user *uaddr, unsi= gned long val, unsigned l unsigned int flags, struct __kernel_timespec __user *timespec, clockid_t clockid); =20 +asmlinkage long sys_futex_requeue(struct futex_waitv __user *waiters, + unsigned int flags, int nr_wake, int nr_requeue); + asmlinkage long sys_nanosleep(struct __kernel_timespec __user *rqtp, struct __kernel_timespec __user *rmtp); asmlinkage long sys_nanosleep_time32(struct old_timespec32 __user *rqtp, diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/u= nistd.h index f6553bd..d9e9cd1 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -826,9 +826,11 @@ __SYSCALL(__NR_fchmodat2, sys_fchmodat2) __SYSCALL(__NR_futex_wake, sys_futex_wake) #define __NR_futex_wait 455 __SYSCALL(__NR_futex_wait, sys_futex_wait) +#define __NR_futex_requeue 456 +__SYSCALL(__NR_futex_requeue, sys_futex_requeue) =20 #undef __NR_syscalls -#define __NR_syscalls 456 +#define __NR_syscalls 457 =20 /* * 32 bit systems traditionally used different diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index dde9b74..8200d86 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -396,6 +396,44 @@ SYSCALL_DEFINE6(futex_wait, return ret; } =20 +/* + * sys_futex_requeue - Requeue a waiter from one futex to another + * @waiters: array describing the source and destination futex + * @flags: unused + * @nr_wake: number of futexes to wake + * @nr_requeue: number of futexes to requeue + * + * Identical to the traditional FUTEX_CMP_REQUEUE op, except it is part of= the + * futex2 family of calls. + */ + +SYSCALL_DEFINE4(futex_requeue, + struct futex_waitv __user *, waiters, + unsigned int, flags, + int, nr_wake, + int, nr_requeue) +{ + struct futex_vector futexes[2]; + u32 cmpval; + int ret; + + if (flags) + return -EINVAL; + + if (!waiters) + return -EINVAL; + + ret =3D futex_parse_waitv(futexes, waiters, 2); + if (ret) + return ret; + + cmpval =3D futexes[0].w.val; + + return futex_requeue(u64_to_user_ptr(futexes[0].w.uaddr), futexes[0].w.fl= ags, + u64_to_user_ptr(futexes[1].w.uaddr), futexes[1].w.flags, + nr_wake, nr_requeue, &cmpval, 0); +} + #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(set_robust_list, struct compat_robust_list_head __user *, head, diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 13df391..9db51ea 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -89,6 +89,7 @@ COND_SYSCALL_COMPAT(get_robust_list); COND_SYSCALL(futex_waitv); COND_SYSCALL(futex_wake); COND_SYSCALL(futex_wait); +COND_SYSCALL(futex_requeue); COND_SYSCALL(kexec_load); COND_SYSCALL_COMPAT(kexec_load); COND_SYSCALL(init_module);