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In the near future cpuset_t objects in struct pcpu will be axed out, but

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as long as this does not happen, we need to fix interfaces to userland
in order to not break run-time accesses to the structure.

Reviwed by:	kib
Tested by:	pluknet
This commit is contained in:
Attilio Rao 2011-05-27 15:50:14 +00:00
parent 7fcdc9a26f
commit d5880f9cdf
2 changed files with 41 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

31
lib/libkvm/kvm_pcpu.c
View File

@ -39,11 +39,13 @@
__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"
@ -118,6 +120,9 @@ _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) {
@ -125,6 +130,10 @@ 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);
@ -137,8 +146,26 @@ kvm_getpcpu(kvm_t *kd, int cpu)
_kvm_err(kd, kd->program, "out of memory");
return ((void *)-1);
}
if (kvm_read(kd, (uintptr_t)pcpu_data[cpu], buf, sizeof(struct pcpu)) !=
sizeof(struct pcpu)) {
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) {
_kvm_err(kd, kd->program, "unable to read per-CPU data");
free(buf);
return ((void *)-1);

14
sys/sys/pcpu.h
View File

@ -163,8 +163,6 @@ struct pcpu {
uint64_t pc_switchtime; /* cpu_ticks() at last csw */
int pc_switchticks; /* `ticks' at last csw */
u_int pc_cpuid; /* This cpu number */
cpuset_t pc_cpumask; /* This cpu mask */
cpuset_t pc_other_cpus; /* Mask of all other cpus */
SLIST_ENTRY(pcpu) pc_allcpu;
struct lock_list_entry *pc_spinlocks;
#ifdef KTR
@ -198,6 +196,18 @@ struct pcpu {
* if only to make kernel debugging easier.
*/
PCPU_MD_FIELDS;
/*
* XXX
* For the time being, keep the cpuset_t objects as the very last
* members of the structure.
* They are actually tagged to be removed soon, but as long as this
* does not happen, it is necessary to find a way to implement
* easilly interfaces to userland and leaving them last makes that
* possible.
*/
cpuset_t pc_cpumask; /* This cpu mask */
cpuset_t pc_other_cpus; /* Mask of all other cpus */
} __aligned(CACHE_LINE_SIZE);
#ifdef _KERNEL