From 364d0522f778b206262efce0932d6cea821879c6 Mon Sep 17 00:00:00 2001
From: attilio <attilio@FreeBSD.org>
Date: Mon, 4 Jul 2011 12:04:52 +0000
Subject: With retirement of cpumask_t and usage of cpuset_t for representing a
 mask of CPUs, pc_other_cpus and pc_cpumask become highly inefficient.

Remove them and replace their usage with custom pc_cpuid magic (as,
atm, pc_cpumask can be easilly represented by (1 << pc_cpuid) and
pc_other_cpus by (all_cpus & ~(1 << pc_cpuid))).

This change is not targeted for MFC because of struct pcpu members
removal and dependency by cpumask_t retirement.

MD review by:	marcel, marius, alc
Tested by:	pluknet
MD testing by:	marcel, marius, gonzo, andreast
---
 lib/libkvm/kvm_pcpu.c | 31 ++-----------------------------
 1 file changed, 2 insertions(+), 29 deletions(-)

(limited to 'lib')

diff --git a/lib/libkvm/kvm_pcpu.c b/lib/libkvm/kvm_pcpu.c
index bc73baf..d7108b4 100644
--- a/lib/libkvm/kvm_pcpu.c
+++ b/lib/libkvm/kvm_pcpu.c
@@ -39,13 +39,11 @@
 __FBSDID("$FreeBSD$");
 
 #include <sys/param.h>
-#include <sys/cpuset.h>
 #include <sys/pcpu.h>
 #include <sys/sysctl.h>
 #include <kvm.h>
 #include <limits.h>
 #include <stdlib.h>
-#include <unistd.h>
 
 #include "kvm_private.h"
 
@@ -120,9 +118,6 @@ _kvm_pcpu_clear(void)
 void *
 kvm_getpcpu(kvm_t *kd, int cpu)
 {
-	long kcpusetsize;
-	ssize_t nbytes;
-	uintptr_t readptr;
 	char *buf;
 
 	if (kd == NULL) {
@@ -130,10 +125,6 @@ kvm_getpcpu(kvm_t *kd, int cpu)
 		return (NULL);
 	}
 
-	kcpusetsize = sysconf(_SC_CPUSET_SIZE);
-	if (kcpusetsize == -1 || (u_long)kcpusetsize > sizeof(cpuset_t))
-		return ((void *)-1);
-
 	if (maxcpu == 0)
 		if (_kvm_pcpu_init(kd) < 0)
 			return ((void *)-1);
@@ -146,26 +137,8 @@ kvm_getpcpu(kvm_t *kd, int cpu)
 		_kvm_err(kd, kd->program, "out of memory");
 		return ((void *)-1);
 	}
-	nbytes = sizeof(struct pcpu) - 2 * kcpusetsize;
-	readptr = (uintptr_t)pcpu_data[cpu];
-	if (kvm_read(kd, readptr, buf, nbytes) != nbytes) {
-		_kvm_err(kd, kd->program, "unable to read per-CPU data");
-		free(buf);
-		return ((void *)-1);
-	}
-
-	/* Fetch the valid cpuset_t objects. */
-	CPU_ZERO((cpuset_t *)(buf + nbytes));
-	CPU_ZERO((cpuset_t *)(buf + nbytes + sizeof(cpuset_t)));
-	readptr += nbytes;
-	if (kvm_read(kd, readptr, buf + nbytes, kcpusetsize) != kcpusetsize) {
-		_kvm_err(kd, kd->program, "unable to read per-CPU data");
-		free(buf);
-		return ((void *)-1);
-	}
-	readptr += kcpusetsize;
-	if (kvm_read(kd, readptr, buf + nbytes + sizeof(cpuset_t),
-	    kcpusetsize) != kcpusetsize) {
+	if (kvm_read(kd, (uintptr_t)pcpu_data[cpu], buf,
+	    sizeof(struct pcpu)) != sizeof(struct pcpu)) {
 		_kvm_err(kd, kd->program, "unable to read per-CPU data");
 		free(buf);
 		return ((void *)-1);
-- 
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