/*
* Copyright (c) 2003-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
*
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the
+ * License may not be used to create, or enable the creation or
+ * redistribution of, unlawful or unlicensed copies of an Apple operating
+ * system, or to circumvent, violate, or enable the circumvention or
+ * violation of, any terms of an Apple operating system software license
+ * agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
*/
#include <vm/vm_kern.h>
#include <mach/machine.h>
#include <i386/cpuid.h>
#include <i386/machine_cpu.h>
#include <i386/lock.h>
-#include <i386/perfmon.h>
/*
* Kernel parameter determining whether threads are halted unconditionally
*/
int idlehalt = 1;
-
-static boolean_t
-cpu_is_hyperthreaded(void)
-{
- if (cpuid_features() & CPUID_FEATURE_HTT)
- return (cpuid_info()->cpuid_logical_per_package /
- cpuid_info()->cpuid_cores_per_package) > 1;
- else
- return FALSE;
-}
-
-void *
-cpu_thread_alloc(int cpu)
+void
+cpu_thread_init(void)
{
- int core_base_cpu;
+ int my_cpu = get_cpu_number();
+ int my_core_base_cpu;
int ret;
- cpu_core_t *core;
+ cpu_core_t *my_core;
- /*
- * Assume that all cpus have the same features.
- */
- if (cpu_is_hyperthreaded()) {
+ /* Have we initialized already for this cpu? */
+ if (cpu_core())
+ return;
+
+ if (cpuid_features() & CPUID_FEATURE_HTT) {
/*
* Get the cpu number of the base thread in the core.
*/
- core_base_cpu = cpu_to_core_cpu(cpu);
- cpu_datap(cpu)->cpu_threadtype = CPU_THREADTYPE_INTEL_HTT;
+ my_core_base_cpu = cpu_to_core_cpu(my_cpu);
+ current_cpu_datap()->cpu_threadtype = CPU_THREADTYPE_INTEL_HTT;
} else {
- core_base_cpu = cpu;
- cpu_datap(cpu)->cpu_threadtype = CPU_THREADTYPE_NONE;
+ my_core_base_cpu = my_cpu;
+ current_cpu_datap()->cpu_threadtype = CPU_THREADTYPE_NONE;
}
- core = (cpu_core_t *) cpu_to_core(core_base_cpu);
- if (core == NULL) {
+ /*
+ * Allocate the base cpu_core struct if none exists.
+ * Since we could be racing with other threads in the same core,
+ * this needs care without using locks. We allocate a new core
+ * structure and assign it atomically, freeing it if we lost the race.
+ */
+ my_core = (cpu_core_t *) cpu_to_core(my_core_base_cpu);
+ if (my_core == NULL) {
+ cpu_core_t *new_core;
+
ret = kmem_alloc(kernel_map,
- (void *) &core, sizeof(cpu_core_t));
+ (void *) &new_core, sizeof(cpu_core_t));
if (ret != KERN_SUCCESS)
- panic("cpu_thread_alloc() kmem_alloc ret=%d\n", ret);
- bzero((void *) core, sizeof(cpu_core_t));
-
- core->base_cpu = core_base_cpu;
-
- atomic_incl((long *) &machine_info.physical_cpu_max, 1);
-
- /* Allocate performance counter data area (if available) */
- core->pmc = pmc_alloc();
+ panic("cpu_thread_init() kmem_alloc ret=%d\n", ret);
+ bzero((void *) new_core, sizeof(cpu_core_t));
+ new_core->base_cpu = my_core_base_cpu;
+ if (atomic_cmpxchg((uint32_t *) &cpu_to_core(my_core_base_cpu),
+ 0, (uint32_t) new_core)) {
+ atomic_incl((long *) &machine_info.physical_cpu, 1);
+ atomic_incl((long *) &machine_info.physical_cpu_max, 1);
+ } else {
+ kmem_free(kernel_map,
+ (vm_offset_t)new_core, sizeof(cpu_core_t));
+ }
+ my_core = (cpu_core_t *) cpu_to_core(my_core_base_cpu);
}
- atomic_incl((long *) &machine_info.logical_cpu_max, 1);
-
- return (void *) core;
-}
-
-void
-cpu_thread_init(void)
-{
- int my_cpu = get_cpu_number();
- cpu_core_t *my_core;
- /*
- * If we're the boot processor we allocate the core structure here.
- * Otherwise the core has already been allocated (by the boot cpu).
- */
- if (my_cpu == master_cpu)
- cpu_to_core(master_cpu) = cpu_thread_alloc(master_cpu);
-
- my_core = cpu_core();
- if (my_core == NULL)
- panic("cpu_thread_init() no core allocated for cpu %d", my_cpu);
+ cpu_to_core(my_cpu) = (struct cpu_core *) my_core;
atomic_incl((long *) &my_core->active_threads, 1);
- atomic_incl((long *) &machine_info.logical_cpu, 1);
- /* Note: cpus are started serially so this isn't as racey as it looks */
- if (my_core->num_threads == 0)
- atomic_incl((long *) &machine_info.physical_cpu, 1);
atomic_incl((long *) &my_core->num_threads, 1);
+ atomic_incl((long *) &machine_info.logical_cpu, 1);
+ atomic_incl((long *) &machine_info.logical_cpu_max, 1);
+
}
/*
{
cpu_core_t *my_core = cpu_core();
- atomic_decl((long *) &machine_info.logical_cpu, 1);
+ /* Note: don't ever decrement the number of physical processors */
atomic_decl((long *) &my_core->active_threads, 1);
- if (atomic_decl_and_test((long *) &my_core->num_threads, 1))
- atomic_decl((long *) &machine_info.physical_cpu, 1);
+ atomic_decl((long *) &my_core->num_threads, 1);
+ atomic_decl((long *) &machine_info.logical_cpu, 1);
cpu_halt();
}
projects / apple / xnu.git / blobdiff