From d936d6d9be7bab125a42add7b5c3e4fbaa4a35d0 Mon Sep 17 00:00:00 2001 From: jhb Date: Wed, 7 Mar 2001 02:36:47 +0000 Subject: - Use _PHOLD and move it before a PROC_UNLOCK to reduce the number of mutex operations in kthread_create(). - Lock a kthread's proc before changing its parent via proc_reparent(). - Test P_KTHREAD not P_SYSTEM in kthread_suspend() and kthread_resume(). P_SYSTEM just means that the process shouldn't be swapped and is used for vinum's daemon for example. - Lock all the signal state used for suspending and resuming kthreads with the proc lock. --- sys/kern/kern_kthread.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) (limited to 'sys/kern/kern_kthread.c') diff --git a/sys/kern/kern_kthread.c b/sys/kern/kern_kthread.c index b322bc1..8dd9cd4 100644 --- a/sys/kern/kern_kthread.c +++ b/sys/kern/kern_kthread.c @@ -91,8 +91,8 @@ kthread_create(void (*func)(void *), void *arg, PROC_LOCK(p2); p2->p_flag |= P_SYSTEM | P_KTHREAD; p2->p_procsig->ps_flag |= PS_NOCLDWAIT; + _PHOLD(p2); PROC_UNLOCK(p2); - PHOLD(p2); /* set up arg0 for 'ps', et al */ va_start(ap, fmt); @@ -119,7 +119,9 @@ kthread_exit(int ecode) { PROCTREE_LOCK(PT_EXCLUSIVE); + PROC_LOCK(curproc); proc_reparent(curproc, initproc); + PROC_UNLOCK(curproc); PROCTREE_LOCK(PT_RELEASE); exit1(curproc, W_EXITCODE(ecode, 0)); } @@ -135,10 +137,13 @@ kthread_suspend(struct proc *p, int timo) * Make sure this is indeed a system process and we can safely * use the p_siglist field. */ - if ((p->p_flag & P_SYSTEM) == 0) + PROC_LOCK(p); + if ((p->p_flag & P_KTHREAD) == 0) { + PROC_UNLOCK(p); return (EINVAL); + } SIGADDSET(p->p_siglist, SIGSTOP); - return tsleep((caddr_t)&p->p_siglist, PPAUSE, "suspkt", timo); + return msleep(&p->p_siglist, &p->p_mtx, PPAUSE | PDROP, "suspkt", timo); } int @@ -148,18 +153,24 @@ kthread_resume(struct proc *p) * Make sure this is indeed a system process and we can safely * use the p_siglist field. */ - if ((p->p_flag & P_SYSTEM) == 0) + PROC_LOCK(p); + if ((p->p_flag & P_KTHREAD) == 0) { + PROC_UNLOCK(p); return (EINVAL); + } SIGDELSET(p->p_siglist, SIGSTOP); - wakeup((caddr_t)&p->p_siglist); + PROC_UNLOCK(p); + wakeup(&p->p_siglist); return (0); } void kthread_suspend_check(struct proc *p) { + PROC_LOCK(p); while (SIGISMEMBER(p->p_siglist, SIGSTOP)) { - wakeup((caddr_t)&p->p_siglist); - tsleep((caddr_t)&p->p_siglist, PPAUSE, "ktsusp", 0); + wakeup(&p->p_siglist); + msleep(&p->p_siglist, &p->p_mtx, PPAUSE, "ktsusp", 0); } + PROC_UNLOCK(p); } -- cgit v1.1