CVS commit: src/sys/dev/pad

[Nathanial Sloss]

Module Name:    src
Committed By:   nat
Date:           Tue Jun  6 07:29:35 UTC 2017

Modified Files:
        src/sys/dev/pad: pad.c

Log Message:
Simplification of rate limiter.  It now works uni/multiprocessor.


To generate a diff of this commit:
cvs rdiff -u -r1.34 -r1.35 src/sys/dev/pad/pad.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/dev/pad/pad.c
diff -u src/sys/dev/pad/pad.c:1.34 src/sys/dev/pad/pad.c:1.35
--- src/sys/dev/pad/pad.c:1.34	Tue Jun  6 07:27:15 2017
+++ src/sys/dev/pad/pad.c	Tue Jun  6 07:29:35 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: pad.c,v 1.34 2017/06/06 07:27:15 nat Exp $ */
+/* $NetBSD: pad.c,v 1.35 2017/06/06 07:29:35 nat Exp $ */
 
 /*-
  * Copyright (c) 2007 Jared D. McNeill <jmcne...@invisible.ca>
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: pad.c,v 1.34 2017/06/06 07:27:15 nat Exp $");
+__KERNEL_RCSID(0, "$NetBSD: pad.c,v 1.35 2017/06/06 07:29:35 nat Exp $");
 
 #include <sys/types.h>
 #include <sys/param.h>
@@ -370,10 +370,11 @@ pad_read(dev_t dev, struct uio *uio, int
 		nowusec = (now.tv_sec * 1000000) + now.tv_usec;
 		lastusec = (sc->sc_last.tv_sec * 1000000) +
 		     sc->sc_last.tv_usec;
-		if (lastusec + TIMENEXTREAD > nowusec &&
-		     sc->sc_bytes_count >= BYTESTOSLEEP) {
-			sc->sc_remainder +=
-			    ((lastusec + TIMENEXTREAD) - nowusec);
+		if (lastusec + TIMENEXTREAD > nowusec) {
+			if (sc->sc_bytes_count >= BYTESTOSLEEP) {
+				sc->sc_remainder +=
+				    ((lastusec + TIMENEXTREAD) - nowusec);
+			}
 			
 			wait_ticks = (hz * sc->sc_remainder) / 1000000;
 			if (wait_ticks > 0) {
@@ -381,19 +382,14 @@ pad_read(dev_t dev, struct uio *uio, int
 				kpause("padwait", TRUE, wait_ticks,
 				    &sc->sc_lock);
 			}
+		}
 
+		if (sc->sc_bytes_count >= BYTESTOSLEEP)
 			sc->sc_bytes_count -= BYTESTOSLEEP;
-			getmicrotime(&sc->sc_last);
-		} else if (sc->sc_bytes_count >= BYTESTOSLEEP) {
-			sc->sc_bytes_count -= BYTESTOSLEEP;
-			getmicrotime(&sc->sc_last);
-		} else if (lastusec + TIMENEXTREAD <= nowusec) {
-			getmicrotime(&sc->sc_last);
-			sc->sc_remainder = 0;
-		}
 
 		err = pad_get_block(sc, &pb, min(uio->uio_resid, PAD_BLKSIZE));
 		if (!err) {
+			getmicrotime(&sc->sc_last);
 			sc->sc_bytes_count += pb.pb_len;
 			mutex_exit(&sc->sc_lock);
 			err = uiomove(pb.pb_ptr, pb.pb_len, uio);