Kill the horrible hack of storing the pid in struct selinfo.

Instead, keep the proc pointer in it and put the selinfo on a list
in struct proc in selrecord. Then clean up the list when leaving
sys_select and sys_poll.

miod@ ok, testing by many, including Bobs spamd boxes.

8 files changed, 55 insertions, 40 deletions

diff --git a/sys/dev/pci/bktr/bktr_core.c b/sys/dev/pci/bktr/bktr_core.c
index c6eaa5bf9dc..23c4f680ebf 100644
--- a/sys/dev/pci/bktr/bktr_core.c
+++ b/sys/dev/pci/bktr/bktr_core.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bktr_core.c,v 1.21 2007/02/11 20:29:22 miod Exp $	*/
+/*	$OpenBSD: bktr_core.c,v 1.22 2007/03/24 16:01:21 art Exp $	*/
 /* $FreeBSD: src/sys/dev/bktr/bktr_core.c,v 1.114 2000/10/31 13:09:56 roger Exp $ */
 
 /*
@@ -810,13 +810,7 @@ common_bktr_intr( void *arg )
 		}
 
 		/* If someone has a select() on /dev/vbi, inform them */
-#ifndef __OpenBSD__
-		if (bktr->vbi_select.si_pid) {
-#else
-		if (bktr->vbi_select.si_selpid) {
-#endif
-			selwakeup(&bktr->vbi_select);
-		}
+		selwakeup(&bktr->vbi_select);
 	}
 
 
diff --git a/sys/dev/wscons/wsdisplay.c b/sys/dev/wscons/wsdisplay.c
index 8b78a22f0a0..68a3e0fc352 100644
--- a/sys/dev/wscons/wsdisplay.c
+++ b/sys/dev/wscons/wsdisplay.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: wsdisplay.c,v 1.77 2007/03/07 06:23:04 miod Exp $ */
+/* $OpenBSD: wsdisplay.c,v 1.78 2007/03/24 16:01:22 art Exp $ */
 /* $NetBSD: wsdisplay.c,v 1.82 2005/02/27 00:27:52 perry Exp $ */
 
 /*
@@ -1402,7 +1402,7 @@ wsdisplaystart(struct tty *tp)
 		splx(s);
 		return;
 	}
-	if (tp->t_outq.c_cc == 0 && tp->t_wsel.si_selpid == 0)
+	if (tp->t_outq.c_cc == 0 && tp->t_wsel.si_selproc == NULL)
 		goto low;
 
 	if ((scr = sc->sc_scr[WSDISPLAYSCREEN(tp->t_dev)]) == NULL) {
diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index e41810455d8..291aa2e5a6a 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: init_main.c,v 1.136 2007/03/19 14:33:28 dlg Exp $	*/
+/*	$OpenBSD: init_main.c,v 1.137 2007/03/24 16:01:22 art Exp $	*/
 /*	$NetBSD: init_main.c,v 1.84.4.1 1996/06/02 09:08:06 mrg Exp $	*/
 
 /*
@@ -296,6 +296,8 @@ main(void *framep)
 	/* Create the file descriptor table. */
 	p->p_fd = fdinit(NULL);
 
+	TAILQ_INIT(&p->p_selects);
+
 	/* Create the limits structures. */
 	p->p_limit = &limit0;
 	for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++)
diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index d19608d9cbc..da8d0df31c4 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_fork.c,v 1.87 2007/03/15 10:22:30 art Exp $	*/
+/*	$OpenBSD: kern_fork.c,v 1.88 2007/03/24 16:01:22 art Exp $	*/
 /*	$NetBSD: kern_fork.c,v 1.29 1996/02/09 18:59:34 christos Exp $	*/
 
 /*
@@ -246,6 +246,8 @@ fork1(struct proc *p1, int exitsig, int flags, void *stack, size_t stacksize,
 	p2->p_cred->p_refcnt = 1;
 	crhold(p1->p_ucred);
 
+	TAILQ_INIT(&p2->p_selects);
+
 	/* bump references to the text vnode (for procfs) */
 	p2->p_textvp = p1->p_textvp;
 	if (p2->p_textvp)
diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
index 31cbafefff7..a79c121c00c 100644
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sys_generic.c,v 1.55 2007/03/15 10:22:30 art Exp $	*/
+/*	$OpenBSD: sys_generic.c,v 1.56 2007/03/24 16:01:22 art Exp $	*/
 /*	$NetBSD: sys_generic.c,v 1.24 1996/03/29 00:25:32 cgd Exp $	*/
 
 /*
@@ -66,6 +66,8 @@ int selscan(struct proc *, fd_set *, fd_set *, int, int, register_t *);
 int seltrue(dev_t, int, struct proc *);
 void pollscan(struct proc *, struct pollfd *, u_int, register_t *);
 
+void sel_clean_proclist(struct proc *);
+
 /*
  * Read system call.
  */
@@ -708,6 +710,7 @@ retry:
 	if (error == 0)
 		goto retry;
 done:
+	sel_clean_proclist(p);
 	atomic_clearbits_int(&p->p_flag, P_SELECT);
 	/* select is not restarted after signals... */
 	if (error == ERESTART)
@@ -781,17 +784,12 @@ seltrue(dev_t dev, int events, struct proc *p)
 void
 selrecord(struct proc *selector, struct selinfo *sip)
 {
-	struct proc *p;
-	pid_t mypid;
-
-	mypid = selector->p_pid;
-	if (sip->si_selpid == mypid)
-		return;
-	if (sip->si_selpid && (p = pfind(sip->si_selpid)) &&
-	    p->p_wchan == (caddr_t)&selwait)
+	if (sip->si_selproc == NULL) {
+		sip->si_selproc = selector;
+		TAILQ_INSERT_TAIL(&selector->p_selects, sip, si_list);
+	} else if (sip->si_selproc != selector) {
 		sip->si_flags |= SI_COLL;
-	else
-		sip->si_selpid = mypid;
+	}
 }
 
 /*
@@ -803,25 +801,42 @@ selwakeup(struct selinfo *sip)
 	struct proc *p;
 	int s;
 
-	if (sip->si_selpid == 0)
-		return;
 	if (sip->si_flags & SI_COLL) {
 		nselcoll++;
 		sip->si_flags &= ~SI_COLL;
 		wakeup(&selwait);
 	}
-	p = pfind(sip->si_selpid);
-	sip->si_selpid = 0;
-	if (p != NULL) {
-		SCHED_LOCK(s);
-		if (p->p_wchan == (caddr_t)&selwait) {
+
+	/*
+	 * We check the process once before locking.
+	 * Then we wake the process and clean up its
+	 * selects list.
+	 */
+	if (sip->si_selproc == NULL)
+		return;
+
+	SCHED_LOCK(s);
+	if ((p = sip->si_selproc) != NULL) {
+		if (p->p_wchan != NULL) {
 			if (p->p_stat == SSLEEP)
 				setrunnable(p);
 			else
 				unsleep(p);
-		} else if (p->p_flag & P_SELECT)
+		} else {
 			atomic_clearbits_int(&p->p_flag, P_SELECT);
-		SCHED_UNLOCK(s);
+		}
+	}
+	SCHED_UNLOCK(s);
+}
+
+void
+sel_clean_proclist(struct proc *p)
+{
+	struct selinfo *sip;
+
+	while ((sip = TAILQ_FIRST(&p->p_selects)) != NULL) {
+		sip->si_selproc = NULL;
+		TAILQ_REMOVE(&p->p_selects, sip, si_list);
 	}
 }
 
@@ -932,6 +947,7 @@ retry:
 		goto retry;
 
 done:
+	sel_clean_proclist(p);
 	atomic_clearbits_int(&p->p_flag, P_SELECT);
 	/*
 	 * NOTE: poll(2) is not restarted after a signal and EWOULDBLOCK is
diff --git a/sys/net/bpf.c b/sys/net/bpf.c
index 4c18bec6b24..0b3e79cd67e 100644
--- a/sys/net/bpf.c
+++ b/sys/net/bpf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: bpf.c,v 1.64 2007/03/04 23:36:34 canacar Exp $	*/
+/*	$OpenBSD: bpf.c,v 1.65 2007/03/24 16:01:22 art Exp $	*/
 /*	$NetBSD: bpf.c,v 1.33 1997/02/21 23:59:35 thorpej Exp $	*/
 
 /*
@@ -496,8 +496,6 @@ bpf_wakeup(struct bpf_d *d)
 		    d->bd_siguid, d->bd_sigeuid);
 
 	selwakeup(&d->bd_sel);
-	/* XXX */
-	d->bd_sel.si_selpid = 0;
 	KNOTE(&d->bd_sel.si_note, 0);
 }
 
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index 7fb12a40c21..f956d2be875 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: proc.h,v 1.91 2007/03/21 09:09:52 art Exp $	*/
+/*	$OpenBSD: proc.h,v 1.92 2007/03/24 16:01:22 art Exp $	*/
 /*	$NetBSD: proc.h,v 1.44 1996/04/22 01:23:21 christos Exp $	*/
 
 /*-
@@ -211,6 +211,8 @@ struct	proc {
 
 	sigset_t p_sigdivert;		/* Signals to be diverted to thread. */
 
+	TAILQ_HEAD(,selinfo) p_selects;	/* selinfos we're selecting on */
+
 /* End area that is zeroed on creation. */
 #define	p_endzero	p_startcopy
 
diff --git a/sys/sys/selinfo.h b/sys/sys/selinfo.h
index 497c2da9d19..535b48deb42 100644
--- a/sys/sys/selinfo.h
+++ b/sys/sys/selinfo.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: selinfo.h,v 1.1 2005/11/21 18:16:46 millert Exp $	*/
+/*	$OpenBSD: selinfo.h,v 1.2 2007/03/24 16:01:22 art Exp $	*/
 
 /*-
  * Copyright (c) 1992, 1993
@@ -41,9 +41,10 @@
  * notified when I/O becomes possible.
  */
 struct selinfo {
-	pid_t	si_selpid;	/* process to be notified */
-	struct	klist si_note;	/* kernel note list */
-	short	si_flags;	/* see below */
+	struct proc *si_selproc;
+	TAILQ_ENTRY(selinfo) si_list;	/* list of selinfo for a process */
+	struct	klist si_note;		/* kernel note list */
+	short	si_flags;		/* see below */
 };
 #define	SI_COLL	0x0001		/* collision occurred */