From 64ed3658d2abe3829f0619e8243c60edcc1d3815 Mon Sep 17 00:00:00 2001
From: cinap_lenrek <cinap_lenrek@felloff.net>
Date: Mon, 15 Jun 2015 17:40:47 +0200
Subject: [PATCH] kernel: add pagechaindone() to wakeup processes waiting for
 memory

we keep the details about palloc in page.c, providing pagechaindone()
for mmu code to be called after a series of pagechainhead() calls.
---
 sys/src/9/alphapc/mmu.c  |  4 ++--
 sys/src/9/bcm/mmu.c      |  6 +++---
 sys/src/9/bitsy/mmu.c    |  6 +++---
 sys/src/9/kw/mmu.c       |  4 ++--
 sys/src/9/pc/mmu.c       |  4 ++--
 sys/src/9/port/page.c    | 15 ++++++++++-----
 sys/src/9/port/portfns.h |  1 +
 sys/src/9/teg2/mmu.c     |  4 ++--
 sys/src/9/xen/mmu.c      |  4 ++--
 sys/src/9/zynq/mmu.c     |  4 ++--
 10 files changed, 29 insertions(+), 23 deletions(-)

diff --git a/sys/src/9/alphapc/mmu.c b/sys/src/9/alphapc/mmu.c
index 0e1e0bb64..21e1b74d7 100644
--- a/sys/src/9/alphapc/mmu.c
+++ b/sys/src/9/alphapc/mmu.c
@@ -110,8 +110,8 @@ mmurelease(Proc *proc)
 			panic("mmurelease: page->ref %d\n", page->ref);
 		pagechainhead(page);
 	}
-	if(proc->mmufree && palloc.r.p)
-		wakeup(&palloc.r);
+	if(proc->mmufree)
+		pagechaindone();
 	proc->mmufree = 0;
 }
 
diff --git a/sys/src/9/bcm/mmu.c b/sys/src/9/bcm/mmu.c
index f068b387c..3ccf38ffc 100644
--- a/sys/src/9/bcm/mmu.c
+++ b/sys/src/9/bcm/mmu.c
@@ -183,11 +183,11 @@ mmurelease(Proc* proc)
 	for(page = proc->mmul2cache; page != nil; page = next){
 		next = page->next;
 		if(--page->ref)
-			panic("mmurelease: page->ref %d", page->ref);
+			panic("mmurelease: page->ref %lud", page->ref);
 		pagechainhead(page);
 	}
-	if(proc->mmul2cache && palloc.r.p)
-		wakeup(&palloc.r);
+	if(proc->mmul2cache != nil)
+		pagechaindone();
 	proc->mmul2cache = nil;
 
 	mmul1empty();
diff --git a/sys/src/9/bitsy/mmu.c b/sys/src/9/bitsy/mmu.c
index ca7df136a..8b7624eaa 100644
--- a/sys/src/9/bitsy/mmu.c
+++ b/sys/src/9/bitsy/mmu.c
@@ -447,14 +447,14 @@ mmurelease(Proc* p)
 
 	mmuptefree(p);
 
-	for(pg = p->mmufree; pg; pg = next){
+	for(pg = p->mmufree; pg != nil; pg = next){
 		next = pg->next;
 		if(--pg->ref)
 			panic("mmurelease: pg->ref %d\n", pg->ref);
 		pagechainhead(pg);
 	}
-	if(p->mmufree && palloc.r.p)
-		wakeup(&palloc.r);
+	if(p->mmufree != nil)
+		pagechaindone();
 	p->mmufree = nil;
 
 	memset(l1table, 0, sizeof(p->l1table));
diff --git a/sys/src/9/kw/mmu.c b/sys/src/9/kw/mmu.c
index 377b1a596..cd633d992 100644
--- a/sys/src/9/kw/mmu.c
+++ b/sys/src/9/kw/mmu.c
@@ -264,8 +264,8 @@ mmurelease(Proc* proc)
 			panic("mmurelease: page->ref %lud", page->ref);
 		pagechainhead(page);
 	}
-	if(proc->mmul2cache && palloc.r.p)
-		wakeup(&palloc.r);
+	if(proc->mmul2cache != nil)
+		pagechaindone();
 	proc->mmul2cache = nil;
 
 	mmul1empty();
diff --git a/sys/src/9/pc/mmu.c b/sys/src/9/pc/mmu.c
index 0994d7be2..cfcdf8793 100644
--- a/sys/src/9/pc/mmu.c
+++ b/sys/src/9/pc/mmu.c
@@ -365,8 +365,8 @@ mmurelease(Proc* proc)
 			panic("mmurelease: page->ref %ld", page->ref);
 		pagechainhead(page);
 	}
-	if(proc->mmufree != nil && palloc.r.p != nil)
-		wakeup(&palloc.r);
+	if(proc->mmufree != nil)
+		pagechaindone();
 	proc->mmufree = nil;
 	if(proc->ldt != nil){
 		free(proc->ldt);
diff --git a/sys/src/9/port/page.c b/sys/src/9/port/page.c
index 9da07b071..c16044512 100644
--- a/sys/src/9/port/page.c
+++ b/sys/src/9/port/page.c
@@ -71,6 +71,15 @@ pagechainhead(Page *p)
 	palloc.freecount++;
 }
 
+void
+pagechaindone(void)
+{
+	if(palloc.pwait[0].p != nil && wakeup(&palloc.pwait[0]) != nil)
+		return;
+	if(palloc.pwait[1].p != nil)
+		wakeup(&palloc.pwait[1]);
+}
+
 static void
 freepages(Page *head, Page *tail, int n)
 {
@@ -79,11 +88,7 @@ freepages(Page *head, Page *tail, int n)
 	palloc.head = head;
 	palloc.freecount += n;
 	unlock(&palloc);
-
-	if(palloc.pwait[0].p != nil && wakeup(&palloc.pwait[0]) != nil)
-		return;
-	if(palloc.pwait[1].p != nil)
-		wakeup(&palloc.pwait[1]);
+	pagechaindone();
 }
 
 int
diff --git a/sys/src/9/port/portfns.h b/sys/src/9/port/portfns.h
index e3b379e00..5fbcf1305 100644
--- a/sys/src/9/port/portfns.h
+++ b/sys/src/9/port/portfns.h
@@ -201,6 +201,7 @@ int		okaddr(uintptr, ulong, int);
 int		openmode(ulong);
 Block*		packblock(Block*);
 Block*		padblock(Block*, int);
+void		pagechaindone(void);
 void		pagechainhead(Page*);
 void		pageinit(void);
 ulong	pagenumber(Page*);
diff --git a/sys/src/9/teg2/mmu.c b/sys/src/9/teg2/mmu.c
index de6c819b8..fc7760eab 100644
--- a/sys/src/9/teg2/mmu.c
+++ b/sys/src/9/teg2/mmu.c
@@ -487,8 +487,8 @@ mmurelease(Proc* proc)
 			panic("mmurelease: page->ref %d", page->ref);
 		pagechainhead(page);
 	}
-	if(proc->mmul2cache && palloc.r.p)
-		wakeup(&palloc.r);
+	if(proc->mmul2cache != nil)
+		pagechaindone();
 	proc->mmul2cache = nil;
 
 	mmul1empty();
diff --git a/sys/src/9/xen/mmu.c b/sys/src/9/xen/mmu.c
index 9adc9cfea..c293fdaeb 100644
--- a/sys/src/9/xen/mmu.c
+++ b/sys/src/9/xen/mmu.c
@@ -288,8 +288,8 @@ mmurelease(Proc* proc)
 			panic("mmurelease: page->ref %ld\n", page->ref);
 		pagechainhead(page);
 	}
-	if(proc->mmufree && palloc.r.p)
-		wakeup(&palloc.r);
+	if(proc->mmufree)
+		pagechaindone();
 	proc->mmufree = 0;
 }
 
diff --git a/sys/src/9/zynq/mmu.c b/sys/src/9/zynq/mmu.c
index d9d9e7cc1..4c561ae70 100644
--- a/sys/src/9/zynq/mmu.c
+++ b/sys/src/9/zynq/mmu.c
@@ -237,8 +237,8 @@ mmurelease(Proc *proc)
 			panic("mmurelease: p->ref %ld", p->ref);
 		pagechainhead(p);
 	}
-	if(proc->mmufree != nil && palloc.r.p != nil)
-		wakeup(&palloc.r);
+	if(proc->mmufree != nil)
+		pagechaindone();
 	proc->mmufree = nil;
 }