PERFORCE change 145362 for review

[Ed Schouten]

http://perforce.freebsd.org/chv.cgi?CH=145362

Change 145362 by ed at ed_dull on 2008/07/17 13:30:21

	Revert the changes to pgfind(). We should fix this somewhere in
	the far future, if we would decompose proctree_lock.

Affected files ...

.. //depot/projects/mpsafetty/share/man/man9/Makefile#2 edit
.. //depot/projects/mpsafetty/share/man/man9/pgfind.9#2 edit
.. //depot/projects/mpsafetty/sys/kern/kern_proc.c#2 edit
.. //depot/projects/mpsafetty/sys/kern/tty.c#3 edit

Differences ...

==== //depot/projects/mpsafetty/share/man/man9/Makefile#2 (text+ko) ====

@@ -884,7 +884,6 @@
 	pfil.9 pfil_hook_get.9 \
 	pfil.9 pfil_remove_hook.9
 MLINKS+=pfind.9 zpfind.9
-MLINKS+=pgfind.9 pgfind_unlocked.9
 MLINKS+=pmap_clear_modify.9 pmap_clear_reference.9
 MLINKS+=pmap_copy.9 pmap_copy_page.9
 MLINKS+=pmap_extract.9 pmap_extract_and_hold.9

==== //depot/projects/mpsafetty/share/man/man9/pgfind.9#2 (text+ko) ====

@@ -35,8 +35,6 @@
 .In sys/proc.h
 .Ft "struct pgrp *"
 .Fn pgfind "pid_t pgid"
-.Ft "struct pgrp *"
-.Fn pgfind_unlocked "pid_t pgid"
 .Sh DESCRIPTION
 The
 .Fn pgfind
@@ -51,9 +49,7 @@
 .Fn pgfind
 locks the
 .Vt pgrp
-structure that is returned, while
-.Fn pgfind_unlocked
-does not.
+structure that is returned.
 .Sh RETURN VALUES
 The
 .Fn pgfind

==== //depot/projects/mpsafetty/sys/kern/kern_proc.c#2 (text+ko) ====

@@ -301,7 +301,7 @@
  * The caller must hold proctree_lock.
  */
 struct pgrp *
-pgfind_unlocked(pgid)
+pgfind(pgid)
 	register pid_t pgid;
 {
 	register struct pgrp *pgrp;
@@ -309,30 +309,15 @@
 	sx_assert(&proctree_lock, SX_LOCKED);
 
 	LIST_FOREACH(pgrp, PGRPHASH(pgid), pg_hash) {
-		if (pgrp->pg_id == pgid)
+		if (pgrp->pg_id == pgid) {
+			PGRP_LOCK(pgrp);
 			return (pgrp);
+		}
 	}
 	return (NULL);
 }
 
 /*
- * Same as pgfind_unlocked(), but acquires the lock on the process
- * group.
- */
-struct pgrp *
-pgfind(pgid)
-	register pid_t pgid;
-{
-	register struct pgrp *pgrp;
-
-	pgrp = pgfind_unlocked(pgid);
-	if (pgrp != NULL)
-		PGRP_LOCK(pgrp);
-
-	return (pgrp);
-}
-
-/*
  * Create a new process group.
  * pgid must be equal to the pid of p.
  * Begin a new session if required.

==== //depot/projects/mpsafetty/sys/kern/tty.c#3 (text+ko) ====

@@ -1438,12 +1438,15 @@
 		struct pgrp *pg;
 
 		/*
-		 * Temporarily unlock the TTY to locate the process
-		 * group.
+		 * XXX: Temporarily unlock the TTY to locate the process
+		 * group. This code would be lot nicer if we would ever
+		 * decompose proctree_lock.
 		 */
 		tty_unlock(tp);
 		sx_slock(&proctree_lock);
-		pg = pgfind_unlocked(*(int *)data);
+		pg = pgfind(*(int *)data);
+		if (pg != NULL)
+			PGRP_UNLOCK(pg);
 		if (pg == NULL || pg->pg_session != td->td_proc->p_session) {
 			sx_sunlock(&proctree_lock);
 			tty_lock(tp);