svn commit: r285633 - in head/sys: kern sys

[Mateusz Guzik]

Author: mjg
Date: Thu Jul 16 14:30:11 2015
New Revision: 285633
URL: https://svnweb.freebsd.org/changeset/base/285633

Log:
  Get rid of lim_update_thread and cred_update_thread.
  
  Their primary use was in thread_cow_update to free up old resources.
  Freeing had to be done with proc lock held and _cow_ funcs already knew
  how to free old structs.

Modified:
  head/sys/kern/init_main.c
  head/sys/kern/kern_prot.c
  head/sys/kern/kern_resource.c
  head/sys/kern/kern_thread.c
  head/sys/sys/resourcevar.h
  head/sys/sys/ucred.h

Modified: head/sys/kern/init_main.c
==============================================================================
--- head/sys/kern/init_main.c	Thu Jul 16 13:57:05 2015	(r285632)
+++ head/sys/kern/init_main.c	Thu Jul 16 14:30:11 2015	(r285633)
@@ -827,6 +827,7 @@ static void
 create_init(const void *udata __unused)
 {
 	struct ucred *newcred, *oldcred;
+	struct thread *td;
 	int error;
 
 	error = fork1(&thread0, RFFDG | RFPROC | RFSTOPPED, 0, &initproc,
@@ -850,7 +851,9 @@ create_init(const void *udata __unused)
 	audit_cred_proc1(newcred);
 #endif
 	proc_set_cred(initproc, newcred);
-	cred_update_thread(FIRST_THREAD_IN_PROC(initproc));
+	td = FIRST_THREAD_IN_PROC(initproc);
+	crfree(td->td_ucred);
+	td->td_ucred = crhold(initproc->p_ucred);
 	PROC_UNLOCK(initproc);
 	sx_xunlock(&proctree_lock);
 	crfree(oldcred);

Modified: head/sys/kern/kern_prot.c
==============================================================================
--- head/sys/kern/kern_prot.c	Thu Jul 16 13:57:05 2015	(r285632)
+++ head/sys/kern/kern_prot.c	Thu Jul 16 14:30:11 2015	(r285633)
@@ -1935,24 +1935,6 @@ cru2x(struct ucred *cr, struct xucred *x
 }
 
 /*
- * small routine to swap a thread's current ucred for the correct one taken
- * from the process.
- */
-void
-cred_update_thread(struct thread *td)
-{
-	struct proc *p;
-	struct ucred *cred;
-
-	p = td->td_proc;
-	cred = td->td_ucred;
-	PROC_LOCK_ASSERT(p, MA_OWNED);
-	td->td_ucred = crhold(p->p_ucred);
-	if (cred != NULL)
-		crfree(cred);
-}
-
-/*
  * Set initial process credentials.
  * Callers are responsible for providing the reference for provided credentials.
  */

Modified: head/sys/kern/kern_resource.c
==============================================================================
--- head/sys/kern/kern_resource.c	Thu Jul 16 13:57:05 2015	(r285632)
+++ head/sys/kern/kern_resource.c	Thu Jul 16 14:30:11 2015	(r285633)
@@ -1436,17 +1436,3 @@ chgkqcnt(struct uidinfo *uip, int diff, 
 
 	return (chglimit(uip, &uip->ui_kqcnt, diff, max, "kqcnt"));
 }
-
-void
-lim_update_thread(struct thread *td)
-{
-	struct proc *p;
-	struct plimit *lim;
-
-	p = td->td_proc;
-	lim = td->td_limit;
-	PROC_LOCK_ASSERT(p, MA_OWNED);
-	td->td_limit = lim_hold(p->p_limit);
-	if (lim != NULL)
-		lim_free(lim);
-}

Modified: head/sys/kern/kern_thread.c
==============================================================================
--- head/sys/kern/kern_thread.c	Thu Jul 16 13:57:05 2015	(r285632)
+++ head/sys/kern/kern_thread.c	Thu Jul 16 14:30:11 2015	(r285633)
@@ -409,9 +409,9 @@ void
 thread_cow_free(struct thread *td)
 {
 
-	if (td->td_ucred)
+	if (td->td_ucred != NULL)
 		crfree(td->td_ucred);
-	if (td->td_limit)
+	if (td->td_limit != NULL)
 		lim_free(td->td_limit);
 }
 
@@ -419,15 +419,27 @@ void
 thread_cow_update(struct thread *td)
 {
 	struct proc *p;
+	struct ucred *oldcred;
+	struct plimit *oldlimit;
 
 	p = td->td_proc;
+	oldcred = NULL;
+	oldlimit = NULL;
 	PROC_LOCK(p);
-	if (td->td_ucred != p->p_ucred)
-		cred_update_thread(td);
-	if (td->td_limit != p->p_limit)
-		lim_update_thread(td);
+	if (td->td_ucred != p->p_ucred) {
+		oldcred = td->td_ucred;
+		td->td_ucred = crhold(p->p_ucred);
+	}
+	if (td->td_limit != p->p_limit) {
+		oldlimit = td->td_limit;
+		td->td_limit = lim_hold(p->p_limit);
+	}
 	td->td_cowgen = p->p_cowgen;
 	PROC_UNLOCK(p);
+	if (oldcred != NULL)
+		crfree(oldcred);
+	if (oldlimit != NULL)
+		lim_free(oldlimit);
 }
 
 /*

Modified: head/sys/sys/resourcevar.h
==============================================================================
--- head/sys/sys/resourcevar.h	Thu Jul 16 13:57:05 2015	(r285632)
+++ head/sys/sys/resourcevar.h	Thu Jul 16 14:30:11 2015	(r285633)
@@ -159,7 +159,5 @@ void	 ui_racct_foreach(void (*callback)(
 	    void *arg2, void *arg3), void *arg2, void *arg3);
 #endif
 
-void	lim_update_thread(struct thread *td);
-
 #endif /* _KERNEL */
 #endif /* !_SYS_RESOURCEVAR_H_ */

Modified: head/sys/sys/ucred.h
==============================================================================
--- head/sys/sys/ucred.h	Thu Jul 16 13:57:05 2015	(r285632)
+++ head/sys/sys/ucred.h	Thu Jul 16 14:30:11 2015	(r285633)
@@ -105,7 +105,6 @@ void	change_svuid(struct ucred *newcred,
 void	crcopy(struct ucred *dest, struct ucred *src);
 struct ucred	*crcopysafe(struct proc *p, struct ucred *cr);
 struct ucred	*crdup(struct ucred *cr);
-void	cred_update_thread(struct thread *td);
 void	proc_set_cred_init(struct proc *p, struct ucred *cr);
 struct ucred	*proc_set_cred(struct proc *p, struct ucred *cr);
 void	crfree(struct ucred *cr);