From: Matthew Dillon <dillon@apollo.backplane.com>
Date: Sat, 8 Dec 2012 05:21:55 +0000 (-0800)
Subject: kernel - Adjust NFS server for new allocvnode() code
X-Git-Tag: v3.2.2~8
X-Git-Url: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff_plain/9106bf2234026fe6086d343402bec0fb5a896be5

kernel - Adjust NFS server for new allocvnode() code

* Adjust the NFS server to check for LWP_MP_VNLRU garbage collection
  requests and act on them.

  This prevents excessive allocation of vnodes by the nfsd's.
---

diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index 3dea3c09a8..7346f16854 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -872,6 +872,25 @@ lwpuserret(struct lwp *lp)
 	}
 }
 
+/*
+ * Kernel threads run from user processes can also accumulate deferred
+ * actions which need to be acted upon.  Callers include:
+ *
+ * nfsd		- Can allocate lots of vnodes
+ */
+void
+lwpkthreaddeferred(void)
+{
+	struct lwp *lp = curthread->td_lwp;
+
+	if (lp) {
+		if (lp->lwp_mpflags & LWP_MP_VNLRU) {
+			atomic_clear_int(&lp->lwp_mpflags, LWP_MP_VNLRU);
+			allocvnode_gc();
+		}
+	}
+}
+
 /*
  * Scan all processes on the allproc list.  The process is automatically
  * held for the callback.  A return value of -1 terminates the loop.
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index ed18513678..971e44ba3d 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -570,6 +570,7 @@ int	pholdzomb (struct proc *);
 void	prelezomb (struct proc *);
 void	pstall (struct proc *, const char *, int);
 void	lwpuserret(struct lwp *);
+void	lwpkthreaddeferred(void);
 
 u_int32_t	procrunnable (void);
 
diff --git a/sys/vfs/nfs/nfs_syscalls.c b/sys/vfs/nfs/nfs_syscalls.c
index c3d5c8a364..dce5f8cf06 100644
--- a/sys/vfs/nfs/nfs_syscalls.c
+++ b/sys/vfs/nfs/nfs_syscalls.c
@@ -661,6 +661,7 @@ nfssvc_nfsd(struct nfsd_srvargs *nsd, caddr_t argp, struct thread *td)
 			    error = (*(nfsrv3_procs[nd->nd_procnum]))(nd,
 						slp, nfsd->nfsd_td, &mreq);
 			    /* NOT YET lwkt_gettoken(&slp->ns_token); */
+			    lwpkthreaddeferred();	/* vnlru issues */
 			}
 			if (mreq == NULL)
 				break;