From 7dfbbc613b6b7f2abaf45e2a3fdf32b1e54a1db5 Mon Sep 17 00:00:00 2001 From: Tijl Coosemans Date: Sun, 22 Apr 2018 16:05:29 +0000 Subject: [PATCH] Make bufdaemon and bufspacedaemon use kthread_suspend_check instead of kproc_suspend_check. In r329612 bufspacedaemon was turned into a thread of the bufdaemon process causing both to call kproc_suspend_check with the same proc argument and that function contains the following while loop: while (SIGISMEMBER(p->p_siglist, SIGSTOP)) { wakeup(&p->p_siglist); msleep(&p->p_siglist, &p->p_mtx, PPAUSE, "kpsusp", 0); } So one thread wakes up the other and the other wakes up the first again, locking up UP machines on shutdown. Also register the shutdown handlers with SHUTDOWN_PRI_LAST + 100 so they run after the syncer has shutdown, because the syncer can cause a situation where bufdaemon help is needed to proceed. PR: 227404 Reviewed by: kib Tested by: cy, rmacklem --- sys/kern/vfs_bio.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c index df48efba483..923a45961ca 100644 --- a/sys/kern/vfs_bio.c +++ b/sys/kern/vfs_bio.c @@ -791,9 +791,12 @@ bufspace_daemon(void *arg) { struct bufdomain *bd; + EVENTHANDLER_REGISTER(shutdown_pre_sync, kthread_shutdown, curthread, + SHUTDOWN_PRI_LAST + 100); + bd = arg; for (;;) { - kproc_suspend_check(curproc); + kthread_suspend_check(); /* * Free buffers from the clean queue until we meet our @@ -3357,8 +3360,8 @@ buf_daemon() /* * This process needs to be suspended prior to shutdown sync. */ - EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, bufdaemonproc, - SHUTDOWN_PRI_LAST); + EVENTHANDLER_REGISTER(shutdown_pre_sync, kthread_shutdown, curthread, + SHUTDOWN_PRI_LAST + 100); /* * Start the buf clean daemons as children threads. @@ -3381,7 +3384,7 @@ buf_daemon() bd_request = 0; mtx_unlock(&bdlock); - kproc_suspend_check(bufdaemonproc); + kthread_suspend_check(); /* * Save speedupreq for this pass and reset to capture new