svn commit: r207548 - in head/sys: kern net

[Alan Cox]

Author: alc
Date: Mon May  3 05:41:50 2010
New Revision: 207548
URL: http://svn.freebsd.org/changeset/base/207548

Log:
  This is the first step in transitioning responsibility for synchronizing
  access to the page's wire_count from the page queues lock to the page lock.
  
  Submitted by:	kmacy

Modified:
  head/sys/kern/uipc_cow.c
  head/sys/kern/uipc_syscalls.c
  head/sys/net/bpf_zerocopy.c

Modified: head/sys/kern/uipc_cow.c
==============================================================================
--- head/sys/kern/uipc_cow.c	Mon May  3 01:13:37 2010	(r207547)
+++ head/sys/kern/uipc_cow.c	Mon May  3 05:41:50 2010	(r207548)
@@ -80,6 +80,7 @@ socow_iodone(void *addr, void *args)
 	pp = sf_buf_page(sf);
 	sf_buf_free(sf);
 	/* remove COW mapping  */
+	vm_page_lock(pp);
 	vm_page_lock_queues();
 	vm_page_cowclear(pp);
 	vm_page_unwire(pp, 0);
@@ -91,6 +92,7 @@ socow_iodone(void *addr, void *args)
 	if (pp->wire_count == 0 && pp->object == NULL)
 		vm_page_free(pp);
 	vm_page_unlock_queues();
+	vm_page_unlock(pp);
 	socow_stats.iodone++;
 }
 
@@ -149,6 +151,7 @@ socow_setup(struct mbuf *m0, struct uio 
 	 */
 	sf = sf_buf_alloc(pp, SFB_CATCH);
 	if (!sf) {
+		vm_page_lock(pp);
 		vm_page_lock_queues();
 		vm_page_cowclear(pp);
 		vm_page_unwire(pp, 0);
@@ -160,6 +163,7 @@ socow_setup(struct mbuf *m0, struct uio 
 		if (pp->wire_count == 0 && pp->object == NULL)
 			vm_page_free(pp);
 		vm_page_unlock_queues();
+		vm_page_unlock(pp);
 		socow_stats.fail_sf_buf++;
 		return(0);
 	}

Modified: head/sys/kern/uipc_syscalls.c
==============================================================================
--- head/sys/kern/uipc_syscalls.c	Mon May  3 01:13:37 2010	(r207547)
+++ head/sys/kern/uipc_syscalls.c	Mon May  3 05:41:50 2010	(r207548)
@@ -1715,6 +1715,7 @@ sf_buf_mext(void *addr, void *args)
 
 	m = sf_buf_page(args);
 	sf_buf_free(args);
+	vm_page_lock(m);
 	vm_page_lock_queues();
 	vm_page_unwire(m, 0);
 	/*
@@ -1725,6 +1726,7 @@ sf_buf_mext(void *addr, void *args)
 	if (m->wire_count == 0 && m->object == NULL)
 		vm_page_free(m);
 	vm_page_unlock_queues();
+	vm_page_unlock(m);
 	if (addr == NULL)
 		return;
 	sfs = addr;
@@ -2136,6 +2138,7 @@ retry_space:
 			if ((sf = sf_buf_alloc(pg,
 			    (mnw ? SFB_NOWAIT : SFB_CATCH))) == NULL) {
 				mbstat.sf_allocfail++;
+				vm_page_lock(pg);
 				vm_page_lock_queues();
 				vm_page_unwire(pg, 0);
 				/*
@@ -2144,6 +2147,7 @@ retry_space:
 				if (pg->wire_count == 0 && pg->object == NULL)
 					vm_page_free(pg);
 				vm_page_unlock_queues();
+				vm_page_unlock(pg);
 				error = (mnw ? EAGAIN : EINTR);
 				break;
 			}

Modified: head/sys/net/bpf_zerocopy.c
==============================================================================
--- head/sys/net/bpf_zerocopy.c	Mon May  3 01:13:37 2010	(r207547)
+++ head/sys/net/bpf_zerocopy.c	Mon May  3 05:41:50 2010	(r207548)
@@ -112,11 +112,13 @@ static void
 zbuf_page_free(vm_page_t pp)
 {
 
+	vm_page_lock(pp);
 	vm_page_lock_queues();
 	vm_page_unwire(pp, 0);
 	if (pp->wire_count == 0 && pp->object == NULL)
 		vm_page_free(pp);
 	vm_page_unlock_queues();
+	vm_page_unlock(pp);
 }
 
 /*