From: Matthew Dillon <dillon@apollo.backplane.com>
Date: Mon, 13 Jul 2009 14:40:48 +0000 (-0700)
Subject: pipe - fix UP build error.
X-Git-Tag: v2.3.2~7
X-Git-Url: https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff_plain/39055880da33b32fe3a60097cfa0d27b58560250

pipe - fix UP build error.

Reported-by: Hasso Tepper <hasso@estpak.ee>
---

diff --git a/sys/kern/sys_pipe.c b/sys/kern/sys_pipe.c
index 21ee2c0033..c98825bec1 100644
--- a/sys/kern/sys_pipe.c
+++ b/sys/kern/sys_pipe.c
@@ -789,20 +789,22 @@ pipe_write(struct file *fp, struct uio *uio, struct ucred *cred, int fflags)
 			if (segsize > space)
 				segsize = space;
 
+#ifdef SMP
 			/*
 			 * If this is the first loop and the reader is
 			 * blocked, do a preemptive wakeup of the reader.
 			 *
-			 * This works for both SMP and UP.  On SMP the IPI
-			 * latency plus the wlock interlock on the reader
-			 * side is the fastest way to get the reader going.
-			 * (The scheduler will hard loop on lock tokens).
+			 * On SMP the IPI latency plus the wlock interlock
+			 * on the reader side is the fastest way to get the
+			 * reader going.  (The scheduler will hard loop on
+			 * lock tokens).
 			 *
 			 * NOTE: We can't clear WANTR here without acquiring
 			 * the rlock, which we don't want to do here!
 			 */
 			if ((wpipe->pipe_state & PIPE_WANTR) && pipe_mpsafe > 1)
 				wakeup(wpipe);
+#endif
 
 			/*
 			 * Transfer segment, which may include a wrap-around.