Date: Thu, 22 Mar 2018 20:47:25 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r331375 - head/sys/kern Message-ID: <201803222047.w2MKlPrQ003999@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: kib Date: Thu Mar 22 20:47:25 2018 New Revision: 331375 URL: https://svnweb.freebsd.org/changeset/base/331375 Log: Do not send signals to init directly from shutdown_nice(9), do it from the task context. shutdown_nice() is used from the fast interrupt handlers, mostly for console drivers, where we cannot lock blockable locks. Schedule the task in the fast queue to send the signal from the proper context. Reviewed by: imp Discussed with: bde Sponsored by: The FreeBSD Foundation MFC after: 1 week Modified: head/sys/kern/kern_shutdown.c Modified: head/sys/kern/kern_shutdown.c ============================================================================== --- head/sys/kern/kern_shutdown.c Thu Mar 22 20:44:27 2018 (r331374) +++ head/sys/kern/kern_shutdown.c Thu Mar 22 20:47:25 2018 (r331375) @@ -72,6 +72,7 @@ __FBSDID("$FreeBSD$"); #include <sys/smp.h> #include <sys/sysctl.h> #include <sys/sysproto.h> +#include <sys/taskqueue.h> #include <sys/vnode.h> #include <sys/watchdog.h> @@ -276,6 +277,28 @@ sys_reboot(struct thread *td, struct reboot_args *uap) return (error); } +static void +shutdown_nice_task_fn(void *arg, int pending __unused) +{ + int howto; + + howto = (uintptr_t)arg; + /* Send a signal to init(8) and have it shutdown the world. */ + PROC_LOCK(initproc); + if (howto & RB_POWEROFF) + kern_psignal(initproc, SIGUSR2); + else if (howto & RB_POWERCYCLE) + kern_psignal(initproc, SIGWINCH); + else if (howto & RB_HALT) + kern_psignal(initproc, SIGUSR1); + else + kern_psignal(initproc, SIGINT); + PROC_UNLOCK(initproc); +} + +static struct task shutdown_nice_task = TASK_INITIALIZER(0, + &shutdown_nice_task_fn, NULL); + /* * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC */ @@ -283,20 +306,14 @@ void shutdown_nice(int howto) { - if (initproc != NULL) { - /* Send a signal to init(8) and have it shutdown the world. */ - PROC_LOCK(initproc); - if (howto & RB_POWEROFF) - kern_psignal(initproc, SIGUSR2); - else if (howto & RB_POWERCYCLE) - kern_psignal(initproc, SIGWINCH); - else if (howto & RB_HALT) - kern_psignal(initproc, SIGUSR1); - else - kern_psignal(initproc, SIGINT); - PROC_UNLOCK(initproc); + if (initproc != NULL && !SCHEDULER_STOPPED()) { + shutdown_nice_task.ta_context = (void *)(uintptr_t)howto; + taskqueue_enqueue(taskqueue_fast, &shutdown_nice_task); } else { - /* No init(8) running, so simply reboot. */ + /* + * No init(8) running, or scheduler would not allow it + * to run, so simply reboot. + */ kern_reboot(howto | RB_NOSYNC); } }
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201803222047.w2MKlPrQ003999>