/*- * 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. */ #if 0 #ifndef lint static char sccsid[] = "@(#)proc_compare.c 8.2 (Berkeley) 9/23/93"; #endif /* not lint */ #endif #include <sys/cdefs.h> #ifndef __APPLE__ __FBSDID("$FreeBSD: src/usr.bin/w/proc_compare.c,v 1.9 2004/04/14 09:34:17 bde Exp $"); #endif #include <sys/param.h> #ifdef __APPLE__ #include <sys/time.h> #endif #include <sys/proc.h> #include <sys/time.h> #include <sys/user.h> #include "extern.h" /* * 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 (p_estcpu). 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 (TDF_SINTR == 0). * 4) Further ties are broken by picking the highest pid. * * If you change this, be sure to consider making the change in the kernel * too (^T in kern/tty.c). * * TODO - consider whether pctcpu should be used. */ #if !HAVE_KVM #define ki_estcpu p_estcpu #define ki_pid p_pid #define ki_slptime p_slptime #define ki_stat p_stat #define ki_tdflags p_tdflags #endif #define ISRUN(p) (((p)->ki_stat == SRUN) || ((p)->ki_stat == SIDL)) #define TESTAB(a, b) ((a)<<1 | (b)) #define ONLYA 2 #define ONLYB 1 #define BOTH 3 #if HAVE_KVM int proc_compare(struct kinfo_proc *p1, struct kinfo_proc *p2) { #else int proc_compare(struct kinfo_proc *arg1, struct kinfo_proc *arg2) { struct extern_proc* p1 = &arg1->kp_proc; struct extern_proc* p2 = &arg2->kp_proc; #endif if (p1 == NULL) return (1); /* * 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 (p2->ki_estcpu > p1->ki_estcpu) return (1); if (p1->ki_estcpu > p2->ki_estcpu) return (0); return (p2->ki_pid > p1->ki_pid); /* tie - return highest pid */ } /* * weed out zombies */ switch (TESTAB(p1->ki_stat == SZOMB, p2->ki_stat == SZOMB)) { case ONLYA: return (1); case ONLYB: return (0); case BOTH: return (p2->ki_pid > p1->ki_pid); /* tie - return highest pid */ } /* * pick the one with the smallest sleep time */ if (p2->ki_slptime > p1->ki_slptime) return (0); if (p1->ki_slptime > p2->ki_slptime) return (1); #ifndef __APPLE__ /* * favor one sleeping in a non-interruptible sleep */ if (p1->ki_tdflags & TDF_SINTR && (p2->ki_tdflags & TDF_SINTR) == 0) return (1); if (p2->ki_tdflags & TDF_SINTR && (p1->ki_tdflags & TDF_SINTR) == 0) return (0); #endif return (p2->ki_pid > p1->ki_pid); /* tie - return highest pid */ }