from tsarna@netbsd.org (sysctl changes to come later):

Death to nfsiod!

It is replaced by kernel threads that do the same thing. The number of
kernel threads used is set with the vfs.nfs.iothreads sysctl.

4 files changed, 78 insertions, 13 deletions

diff --git a/sys/nfs/nfs.h b/sys/nfs/nfs.h
index 06c01af9b99..31e7a5b768b 100644
--- a/sys/nfs/nfs.h
+++ b/sys/nfs/nfs.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nfs.h,v 1.7 1998/05/25 09:12:26 deraadt Exp $	*/
+/*	$OpenBSD: nfs.h,v 1.8 2000/05/19 16:36:03 mickey Exp $	*/
 /*	$NetBSD: nfs.h,v 1.10.4.1 1996/05/27 11:23:56 fvdl Exp $	*/
 
 /*
@@ -237,11 +237,13 @@ struct nfsstats {
 /*
  * fs.nfs sysctl(3) identifiers
  */
-#define NFS_NFSSTATS	1		/* struct: struct nfsstats */
+#define	NFS_NFSSTATS	1	/* struct: struct nfsstats */
+#define	NFS_NIOTHREADS	2	/* number of i/o threads */
 
 #define FS_NFS_NAMES { \
-		       { 0, 0 }, \
-		       { "nfsstats", CTLTYPE_STRUCT }, \
+			{ 0, 0 }, \
+			{ "nfsstats", CTLTYPE_STRUCT }, \
+			{ "niothreads", CTLTYPE_INT } \
 }
 
 /*
@@ -253,6 +255,7 @@ struct nfsstats {
  * by them and break.
  */
 #ifdef _KERNEL
+extern int nfs_niothreads;
 
 struct uio; struct buf; struct vattr; struct nameidata;	/* XXX */
 
@@ -468,5 +471,4 @@ int nfsd_head_flag;
 		sizeof (struct ucred)))
 
 #endif	/* _KERNEL */
-
 #endif /* _NFS_NFS_H */
diff --git a/sys/nfs/nfs_syscalls.c b/sys/nfs/nfs_syscalls.c
index c092d8cb684..4c09245f4fb 100644
--- a/sys/nfs/nfs_syscalls.c
+++ b/sys/nfs/nfs_syscalls.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nfs_syscalls.c,v 1.13 2000/02/07 04:47:53 assar Exp $	*/
+/*	$OpenBSD: nfs_syscalls.c,v 1.14 2000/05/19 16:36:03 mickey Exp $	*/
 /*	$NetBSD: nfs_syscalls.c,v 1.19 1996/02/18 11:53:52 fvdl Exp $	*/
 
 /*
@@ -58,6 +58,8 @@
 #include <sys/namei.h>
 #include <sys/syslog.h>
 #include <sys/filedesc.h>
+#include <sys/signalvar.h>
+#include <sys/kthread.h>
 
 #include <sys/syscallargs.h>
 
@@ -105,7 +107,8 @@ static struct nfsdrt nfsdrt;
 #define	FALSE	0
 
 #ifdef NFSCLIENT
-static int nfs_asyncdaemon[NFS_MAXASYNCDAEMON];
+struct proc *nfs_asyncdaemon[NFS_MAXASYNCDAEMON];
+int nfs_niothreads = -1;
 #endif
 
 #ifdef NFSSERVER
@@ -839,7 +842,7 @@ nfsd_rt(sotype, nd, cacherep)
 
 #ifdef NFSCLIENT
 /*
- * Asynchronous I/O daemons for client nfs.
+ * Asynchronous I/O threads for client nfs.
  * They do read-ahead and write-behind operations on the block I/O cache.
  * Never returns unless it fails or gets killed.
  */
@@ -857,14 +860,15 @@ nfssvc_iod(p)
 	 */
 	myiod = -1;
 	for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
-		if (nfs_asyncdaemon[i] == 0) {
-			nfs_asyncdaemon[i]++;
+		if (nfs_asyncdaemon[i] == NULL) {
 			myiod = i;
 			break;
 		}
 	if (myiod == -1)
 		return (EBUSY);
+	nfs_asyncdaemon[myiod] = p;
 	nfs_numasync++;
+	p->p_holdcnt++;
 	/*
 	 * Just loop around doin our stuff until SIGKILL
 	 */
@@ -912,13 +916,53 @@ nfssvc_iod(p)
 		} while ((bp = nbp) != NULL);
 	    }
 	    if (error) {
-		nfs_asyncdaemon[myiod] = 0;
+		nfs_asyncdaemon[myiod] = NULL;
 		nfs_numasync--;
 		return (error);
 	    }
 	}
 }
 
+void
+start_nfsio(arg)
+	void *arg;
+{
+	nfssvc_iod(curproc);
+	
+	kthread_exit(0);
+}
+
+void
+nfs_getset_niothreads(set)
+	int set;
+{
+	int i, have, start;
+	
+	for (have = 0, i = 0; i < NFS_MAXASYNCDAEMON; i++)
+		if (nfs_asyncdaemon[i] != NULL)
+			have++;
+
+	if (set) {
+		/* clamp to sane range */
+		nfs_niothreads = max(0, min(nfs_niothreads, NFS_MAXASYNCDAEMON));
+
+		start = nfs_niothreads - have;
+
+		while (start > 0) {
+			kthread_create(start_nfsio, NULL, NULL, "nfsio");
+			start--;
+		}
+
+		for (i = 0; (start < 0) && (i < NFS_MAXASYNCDAEMON); i++)
+			if (nfs_asyncdaemon[i] != NULL) {
+				psignal(nfs_asyncdaemon[i], SIGKILL);
+				start++;
+			}
+	} else {
+		if (nfs_niothreads >= 0)
+			nfs_niothreads = have;
+	}
+}
 
 /*
  * Get an authorization string for the uid by having the mount_nfs sitting
diff --git a/sys/nfs/nfs_var.h b/sys/nfs/nfs_var.h
index bd2ae3658e2..51b1bbbfc5d 100644
--- a/sys/nfs/nfs_var.h
+++ b/sys/nfs/nfs_var.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nfs_var.h,v 1.10 2000/02/07 04:48:42 assar Exp $	*/
+/*	$OpenBSD: nfs_var.h,v 1.11 2000/05/19 16:36:03 mickey Exp $	*/
 /*	$NetBSD: nfs_var.h,v 1.3 1996/02/18 11:53:54 fvdl Exp $	*/
 
 /*
@@ -305,6 +305,8 @@ void nfsrv_zapsock __P((struct nfssvc_sock *));
 void nfsrv_slpderef __P((struct nfssvc_sock *));
 void nfsrv_init __P((int));
 int nfssvc_iod __P((struct proc *));
+void start_nfsio __P((void *));
+void nfs_getset_niothreads __P((int));
 int nfs_getauth __P((struct nfsmount *, struct nfsreq *, struct ucred *,
 		     char **, int *, char *, int *, NFSKERBKEY_T));
 int nfs_getnickauth __P((struct nfsmount *, struct ucred *, char **, int *,
diff --git a/sys/nfs/nfs_vfsops.c b/sys/nfs/nfs_vfsops.c
index 4b24082186e..9b4ce097747 100644
--- a/sys/nfs/nfs_vfsops.c
+++ b/sys/nfs/nfs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: nfs_vfsops.c,v 1.30 2000/02/07 04:57:17 assar Exp $	*/
+/*	$OpenBSD: nfs_vfsops.c,v 1.31 2000/05/19 16:36:04 mickey Exp $	*/
 /*	$NetBSD: nfs_vfsops.c,v 1.46.4.1 1996/05/25 22:40:35 fvdl Exp $	*/
 
 /*
@@ -53,6 +53,7 @@
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/systm.h>
+#include <sys/sysctl.h>
 
 #include <net/if.h>
 #include <net/route.h>
@@ -628,6 +629,12 @@ nfs_mount(mp, path, data, ndp, p)
 		return (EPROGMISMATCH);
 	if (error)
 		return (error);
+
+	if (nfs_niothreads < 0) {
+		nfs_niothreads = 4;
+		nfs_getset_niothreads(TRUE);
+	}
+
 	if (mp->mnt_flag & MNT_UPDATE) {
 		register struct nfsmount *nmp = VFSTONFS(mp);
 
@@ -960,6 +967,15 @@ nfs_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
 		}
 		return 0;
 
+	case NFS_NIOTHREADS:
+		nfs_getset_niothreads(0);
+
+		rv = sysctl_int(oldp, oldlenp, newp, newlen, &nfs_niothreads);
+		if (newp)
+			nfs_getset_niothreads(1);
+
+		return rv;
+
 	default:
 		return EOPNOTSUPP;
 	}
@@ -1036,3 +1052,4 @@ nfs_checkexp(mp, nam, exflagsp, credanonp)
 {
 	return (EOPNOTSUPP);
 }
+