Module Name: src
Committed By: christos
Date: Fri Oct 21 02:09:00 UTC 2011
Modified Files:
src/common/lib/libutil: Makefile.inc
Added Files:
src/common/lib/libutil: proc_compare.c
Log Message:
Add a version of proc_compare that works both for kernel and userland
(and uses the same algorithm!)
To generate a diff of this commit:
cvs rdiff -u -r1.2 -r1.3 src/common/lib/libutil/Makefile.inc
cvs rdiff -u -r0 -r1.1 src/common/lib/libutil/proc_compare.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/common/lib/libutil/Makefile.inc
diff -u src/common/lib/libutil/Makefile.inc:1.2 src/common/lib/libutil/Makefile.inc:1.3
--- src/common/lib/libutil/Makefile.inc:1.2 Tue Aug 16 06:33:17 2011
+++ src/common/lib/libutil/Makefile.inc Thu Oct 20 22:09:00 2011
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile.inc,v 1.2 2011/08/16 10:33:17 christos Exp $
+# $NetBSD: Makefile.inc,v 1.3 2011/10/21 02:09:00 christos Exp $
.PATH.c: ${.PARSEDIR}
-SRCS+= snprintb.c
+SRCS+= snprintb.c proc_compare.c
COPTS.snprintb.c = -Wno-format-nonliteral
Added files:
Index: src/common/lib/libutil/proc_compare.c
diff -u /dev/null src/common/lib/libutil/proc_compare.c:1.1
--- /dev/null Thu Oct 20 22:09:00 2011
+++ src/common/lib/libutil/proc_compare.c Thu Oct 20 22:09:00 2011
@@ -0,0 +1,146 @@
+/* $NetBSD: proc_compare.c,v 1.1 2011/10/21 02:09:00 christos Exp $ */
+
+/*-
+ * Copyright (c) 1990, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+#ifndef _STANDALONE
+# ifndef _KERNEL
+
+# if HAVE_NBTOOL_CONFIG_H
+# include "nbtool_config.h"
+# endif
+
+# include <sys/cdefs.h>
+# if defined(LIBC_SCCS) && !defined(lint)
+__RCSID("$NetBSD: proc_compare.c,v 1.1 2011/10/21 02:09:00 christos Exp $");
+# endif
+
+# include <sys/types.h>
+# include <sys/inttypes.h>
+# include <sys/sysctl.h>
+# include <stdio.h>
+# include <util.h>
+# include <errno.h>
+# define PROC struct kinfo_proc2
+# define LWP struct kinfo_lwp
+# define P_RTIME_SEC p_rtime_sec
+# define P_RTIME_USEC p_rtime_usec
+# else
+# include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: proc_compare.c,v 1.1 2011/10/21 02:09:00 christos Exp $");
+# include <sys/param.h>
+# include <sys/inttypes.h>
+# include <sys/systm.h>
+# include <sys/proc.h>
+# include <sys/lwp.h>
+# include <lib/libkern/libkern.h>
+# define PROC struct proc
+# define LWP struct lwp
+# define P_RTIME_SEC p_rtime.sec
+# define P_RTIME_USEC p_rtime.frac
+# endif
+/*
+ * Returns 1 if p2 is "better" than p1
+ *
+ * The algorithm for picking the "interesting" process is thus:
+ *
+ * 1) Only foreground processes are eligible - implied.
+ * 2) Runnable processes are favored over anything else. The runner
+ * with the highest CPU utilization is picked (l_pctcpu). Ties are
+ * broken by picking the highest pid.
+ * 3) The sleeper with the shortest sleep time is next. With ties,
+ * we pick out just "short-term" sleepers (P_SINTR == 0).
+ * 4) Further ties are broken by picking the one started last.
+ * 5) Finally the one with the biggest pid wins, but that is nonsense
+ * because of pid randomization.
+ */
+#define ISRUN(p) ((p)->p_nrlwps > 0)
+#define TESTAB(a, b) (((a) << 1) | (b))
+#define ONLYA 2
+#define ONLYB 1
+#define BOTH 3
+
+int
+proc_compare(const PROC *p1, const LWP *l1, const PROC *p2, const LWP *l2)
+{
+ /*
+ * see if at least one of them is runnable
+ */
+ switch (TESTAB(ISRUN(p1), ISRUN(p2))) {
+ case ONLYA:
+ return 0;
+ case ONLYB:
+ return 1;
+ case BOTH:
+ /*
+ * tie - favor one with highest recent CPU utilization
+ */
+ if (l2->l_pctcpu > l1->l_pctcpu)
+ return 1;
+ goto out;
+ }
+ /*
+ * weed out zombies
+ */
+ switch (TESTAB(P_ZOMBIE(p1), P_ZOMBIE(p2))) {
+ case ONLYA:
+ return 1;
+ case ONLYB:
+ return 0;
+ case BOTH:
+ goto out;
+ }
+ /*
+ * pick the one with the smallest sleep time
+ */
+ if (l1->l_slptime < l2->l_slptime)
+ return 0;
+ if (l2->l_slptime < l1->l_slptime)
+ return 1;
+
+ /*
+ * favor one sleeping in a non-interruptible sleep
+ */
+ if ((l1->l_flag & LW_SINTR) && (l2->l_flag & LW_SINTR) == 0)
+ return 0;
+ if ((l2->l_flag & LW_SINTR) && (l1->l_flag & LW_SINTR) == 0)
+ return 1;
+out:
+ /* tie, return the one with the smallest realtime */
+ if (p1->P_RTIME_SEC < p2->P_RTIME_SEC)
+ return 0;
+ if (p2->P_RTIME_SEC < p1->P_RTIME_SEC)
+ return 1;
+ if (p1->P_RTIME_USEC < p2->P_RTIME_USEC)
+ return 0;
+ if (p2->P_RTIME_USEC < p1->P_RTIME_USEC)
+ return 1;
+
+ return p2->p_pid > p1->p_pid; /* Nonsense */
+}
+#endif /* STANDALONE */
