From owner-dev-commits-src-all@freebsd.org Tue Jun 22 01:46:11 2021 Return-Path: Delivered-To: dev-commits-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 9ADE9653C97; Tue, 22 Jun 2021 01:46:11 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4G88Pb3bpcz4TJr; Tue, 22 Jun 2021 01:46:11 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 2E1F327E59; Tue, 22 Jun 2021 01:46:11 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 15M1kBDw066025; Tue, 22 Jun 2021 01:46:11 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 15M1kBjO066024; Tue, 22 Jun 2021 01:46:11 GMT (envelope-from git) Date: Tue, 22 Jun 2021 01:46:11 GMT Message-Id: <202106220146.15M1kBjO066024@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Konstantin Belousov Subject: git: 2ea2987d14d4 - stable/13 - Add a knob to disable dequeueing SIGCHLD on waiting for live process MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: kib X-Git-Repository: src X-Git-Refname: refs/heads/stable/13 X-Git-Reftype: branch X-Git-Commit: 2ea2987d14d4d58fc6afe15e790dc9aa075038cc Auto-Submitted: auto-generated X-BeenThere: dev-commits-src-all@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for all branches of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Jun 2021 01:46:11 -0000 The branch stable/13 has been updated by kib: URL: https://cgit.FreeBSD.org/src/commit/?id=2ea2987d14d4d58fc6afe15e790dc9aa075038cc commit 2ea2987d14d4d58fc6afe15e790dc9aa075038cc Author: Konstantin Belousov AuthorDate: 2021-06-05 18:24:35 +0000 Commit: Konstantin Belousov CommitDate: 2021-06-22 01:45:32 +0000 Add a knob to disable dequeueing SIGCHLD on waiting for live process (cherry picked from commit a12e901a5a65417849c1ccf1e37b8d092fa438da) --- sys/kern/kern_exit.c | 14 +++++++++++--- sys/sys/sysent.h | 1 + 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c index cb5996982a3a..fcd8b39a8ee2 100644 --- a/sys/kern/kern_exit.c +++ b/sys/kern/kern_exit.c @@ -105,6 +105,11 @@ SYSCTL_INT(_kern, OID_AUTO, kill_on_debugger_exit, CTLFLAG_RWTUN, &kern_kill_on_dbg_exit, 0, "Kill ptraced processes when debugger exits"); +static bool kern_wait_dequeue_sigchld = 1; +SYSCTL_BOOL(_kern, OID_AUTO, wait_dequeue_sigchld, CTLFLAG_RWTUN, + &kern_wait_dequeue_sigchld, 0, + "Dequeue SIGCHLD on wait(2) for live process"); + struct proc * proc_realparent(struct proc *child) { @@ -1207,9 +1212,12 @@ report_alive_proc(struct thread *td, struct proc *p, siginfo_t *siginfo, p->p_flag &= ~P_CONTINUED; else p->p_flag |= P_WAITED; - PROC_LOCK(td->td_proc); - sigqueue_take(p->p_ksi); - PROC_UNLOCK(td->td_proc); + if (kern_wait_dequeue_sigchld && + (td->td_proc->p_sysent->sv_flags & SV_SIG_WAITNDQ) == 0) { + PROC_LOCK(td->td_proc); + sigqueue_take(p->p_ksi); + PROC_UNLOCK(td->td_proc); + } } sx_xunlock(&proctree_lock); if (siginfo != NULL) { diff --git a/sys/sys/sysent.h b/sys/sys/sysent.h index 95e9dcb1a335..8b0903f7dcc0 100644 --- a/sys/sys/sysent.h +++ b/sys/sys/sysent.h @@ -162,6 +162,7 @@ struct sysentvec { #define SV_ASLR 0x080000 /* ASLR allowed. */ #define SV_RNG_SEED_VER 0x100000 /* random(4) reseed generation. */ #define SV_SIG_DISCIGN 0x200000 /* Do not discard ignored signals */ +#define SV_SIG_WAITNDQ 0x400000 /* Wait does not dequeue SIGCHLD */ #define SV_ABI_MASK 0xff #define SV_PROC_FLAG(p, x) ((p)->p_sysent->sv_flags & (x))