From: mpi <mpi@openbsd.org>
Date: Mon, 1 Aug 2022 14:15:46 +0000 (+0000)
Subject: Introduce and use uvm_pagewait() where PG_WANTED is set.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=5b4619ea1bd10245593be657f96db18a630d6689;p=openbsd

Introduce and use uvm_pagewait() where PG_WANTED is set.

No change in behavior.

ok kn@, semarie@, kettenis@
---

diff --git a/sys/uvm/uvm_amap.c b/sys/uvm/uvm_amap.c
index 39c58fde83a..d2154808797 100644
--- a/sys/uvm/uvm_amap.c
+++ b/sys/uvm/uvm_amap.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_amap.c,v 1.90 2021/08/30 16:59:17 mpi Exp $	*/
+/*	$OpenBSD: uvm_amap.c,v 1.91 2022/08/01 14:15:46 mpi Exp $	*/
 /*	$NetBSD: uvm_amap.c,v 1.27 2000/11/25 06:27:59 chs Exp $	*/
 
 /*
@@ -781,9 +781,7 @@ ReStart:
 			 * it and then restart.
 			 */
 			if (pg->pg_flags & PG_BUSY) {
-				atomic_setbits_int(&pg->pg_flags, PG_WANTED);
-				rwsleep_nsec(pg, amap->am_lock, PVM | PNORELOCK,
-				    "cownow", INFSLP);
+				uvm_pagewait(pg, amap->am_lock, "cownow");
 				goto ReStart;
 			}
 
diff --git a/sys/uvm/uvm_aobj.c b/sys/uvm/uvm_aobj.c
index 1c85448f0e8..5e7098adbb2 100644
--- a/sys/uvm/uvm_aobj.c
+++ b/sys/uvm/uvm_aobj.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_aobj.c,v 1.105 2022/07/24 11:00:22 mpi Exp $	*/
+/*	$OpenBSD: uvm_aobj.c,v 1.106 2022/08/01 14:15:46 mpi Exp $	*/
 /*	$NetBSD: uvm_aobj.c,v 1.39 2001/02/18 21:19:08 chs Exp $	*/
 
 /*
@@ -835,9 +835,8 @@ uao_detach(struct uvm_object *uobj)
 	while ((pg = RBT_ROOT(uvm_objtree, &uobj->memt)) != NULL) {
 		pmap_page_protect(pg, PROT_NONE);
 		if (pg->pg_flags & PG_BUSY) {
-			atomic_setbits_int(&pg->pg_flags, PG_WANTED);
-			rwsleep_nsec(pg, uobj->vmobjlock, PVM, "uao_det",
-			    INFSLP);
+			uvm_pagewait(pg, uobj->vmobjlock, "uao_det");
+			rw_enter(uobj->vmobjlock, RW_WRITE);
 			continue;
 		}
 		uao_dropswap(&aobj->u_obj, pg->offset >> PAGE_SHIFT);
@@ -909,9 +908,8 @@ uao_flush(struct uvm_object *uobj, voff_t start, voff_t stop, int flags)
 
 		/* Make sure page is unbusy, else wait for it. */
 		if (pg->pg_flags & PG_BUSY) {
-			atomic_setbits_int(&pg->pg_flags, PG_WANTED);
-			rwsleep_nsec(pg, uobj->vmobjlock, PVM, "uaoflsh",
-			    INFSLP);
+			uvm_pagewait(pg, uobj->vmobjlock, "uaoflsh");
+			rw_enter(uobj->vmobjlock, RW_WRITE);
 			curoff -= PAGE_SIZE;
 			continue;
 		}
@@ -1147,9 +1145,8 @@ uao_get(struct uvm_object *uobj, voff_t offset, struct vm_page **pps,
 
 			/* page is there, see if we need to wait on it */
 			if ((ptmp->pg_flags & PG_BUSY) != 0) {
-				atomic_setbits_int(&ptmp->pg_flags, PG_WANTED);
-				rwsleep_nsec(ptmp, uobj->vmobjlock, PVM,
-				    "uao_get", INFSLP);
+				uvm_pagewait(ptmp, uobj->vmobjlock, "uao_get");
+				rw_enter(uobj->vmobjlock, RW_WRITE);
 				continue;	/* goto top of pps while loop */
 			}
 
diff --git a/sys/uvm/uvm_km.c b/sys/uvm/uvm_km.c
index 1f1396e33d8..d5dcc878466 100644
--- a/sys/uvm/uvm_km.c
+++ b/sys/uvm/uvm_km.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_km.c,v 1.150 2022/06/07 12:07:45 kettenis Exp $	*/
+/*	$OpenBSD: uvm_km.c,v 1.151 2022/08/01 14:15:46 mpi Exp $	*/
 /*	$NetBSD: uvm_km.c,v 1.42 2001/01/14 02:10:01 thorpej Exp $	*/
 
 /* 
@@ -255,9 +255,8 @@ uvm_km_pgremove(struct uvm_object *uobj, vaddr_t startva, vaddr_t endva)
 	for (curoff = start ; curoff < end ; curoff += PAGE_SIZE) {
 		pp = uvm_pagelookup(uobj, curoff);
 		if (pp && pp->pg_flags & PG_BUSY) {
-			atomic_setbits_int(&pp->pg_flags, PG_WANTED);
-			rwsleep_nsec(pp, uobj->vmobjlock, PVM, "km_pgrm",
-			    INFSLP);
+			uvm_pagewait(pp, uobj->vmobjlock, "km_pgrm");
+			rw_enter(uobj->vmobjlock, RW_WRITE);
 			curoff -= PAGE_SIZE; /* loop back to us */
 			continue;
 		}
diff --git a/sys/uvm/uvm_page.c b/sys/uvm/uvm_page.c
index f4ad82de86b..4af64e2d4ca 100644
--- a/sys/uvm/uvm_page.c
+++ b/sys/uvm/uvm_page.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page.c,v 1.168 2022/07/24 11:00:22 mpi Exp $	*/
+/*	$OpenBSD: uvm_page.c,v 1.169 2022/08/01 14:15:46 mpi Exp $	*/
 /*	$NetBSD: uvm_page.c,v 1.44 2000/11/27 08:40:04 chs Exp $	*/
 
 /*
@@ -1087,6 +1087,23 @@ uvm_page_unbusy(struct vm_page **pgs, int npgs)
 	}
 }
 
+/*
+ * uvm_pagewait: wait for a busy page
+ *
+ * => page must be known PG_BUSY
+ * => object must be locked
+ * => object will be unlocked on return
+ */
+void
+uvm_pagewait(struct vm_page *pg, struct rwlock *lock, const char *wmesg)
+{
+	KASSERT(rw_lock_held(lock));
+	KASSERT((pg->pg_flags & PG_BUSY) != 0);
+
+	atomic_setbits_int(&pg->pg_flags, PG_WANTED);
+	rwsleep_nsec(pg, lock, PVM | PNORELOCK, wmesg, INFSLP);
+}
+
 #if defined(UVM_PAGE_TRKOWN)
 /*
  * uvm_page_own: set or release page ownership
diff --git a/sys/uvm/uvm_page.h b/sys/uvm/uvm_page.h
index eab5cc4c6af..b70ec7d3bfb 100644
--- a/sys/uvm/uvm_page.h
+++ b/sys/uvm/uvm_page.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page.h,v 1.68 2022/05/12 12:48:36 mpi Exp $	*/
+/*	$OpenBSD: uvm_page.h,v 1.69 2022/08/01 14:15:46 mpi Exp $	*/
 /*	$NetBSD: uvm_page.h,v 1.19 2000/12/28 08:24:55 chs Exp $	*/
 
 /* 
@@ -233,7 +233,7 @@ void		uvm_pagefree(struct vm_page *);
 void		uvm_page_unbusy(struct vm_page **, int);
 struct vm_page	*uvm_pagelookup(struct uvm_object *, voff_t);
 void		uvm_pageunwire(struct vm_page *);
-void		uvm_pagewait(struct vm_page *, int);
+void		uvm_pagewait(struct vm_page *, struct rwlock *, const char *);
 void		uvm_pagewake(struct vm_page *);
 void		uvm_pagewire(struct vm_page *);
 void		uvm_pagezero(struct vm_page *);
diff --git a/sys/uvm/uvm_vnode.c b/sys/uvm/uvm_vnode.c
index b35e864670c..8c1657cbe86 100644
--- a/sys/uvm/uvm_vnode.c
+++ b/sys/uvm/uvm_vnode.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_vnode.c,v 1.125 2022/07/07 13:52:20 mpi Exp $	*/
+/*	$OpenBSD: uvm_vnode.c,v 1.126 2022/08/01 14:15:46 mpi Exp $	*/
 /*	$NetBSD: uvm_vnode.c,v 1.36 2000/11/24 20:34:01 chs Exp $	*/
 
 /*
@@ -684,11 +684,10 @@ uvn_flush(struct uvm_object *uobj, voff_t start, voff_t stop, int flags)
 				}
 			} else if (flags & PGO_FREE) {
 				if (pp->pg_flags & PG_BUSY) {
-					atomic_setbits_int(&pp->pg_flags,
-					    PG_WANTED);
 					uvm_unlock_pageq();
-					rwsleep_nsec(pp, uobj->vmobjlock, PVM,
-					    "uvn_flsh", INFSLP);
+					uvm_pagewait(pp, uobj->vmobjlock,
+					    "uvn_flsh");
+					rw_enter(uobj->vmobjlock, RW_WRITE);
 					uvm_lock_pageq();
 					curoff -= PAGE_SIZE;
 					continue;
@@ -1054,9 +1053,8 @@ uvn_get(struct uvm_object *uobj, voff_t offset, struct vm_page **pps,
 
 			/* page is there, see if we need to wait on it */
 			if ((ptmp->pg_flags & PG_BUSY) != 0) {
-				atomic_setbits_int(&ptmp->pg_flags, PG_WANTED);
-				rwsleep_nsec(ptmp, uobj->vmobjlock, PVM,
-				    "uvn_get", INFSLP);
+				uvm_pagewait(ptmp, uobj->vmobjlock, "uvn_get");
+				rw_enter(uobj->vmobjlock, RW_WRITE);
 				continue;	/* goto top of pps while loop */
 			}