/*
* Copyright (c) 2003-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
*
- * 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. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
+ * 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
+ *
+ * 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_HEADER_END@
+ *
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
*/
#include <mach/std_types.h>
#include <i386/cpuid.h>
#include <i386/lock.h>
#include <vm/vm_kern.h>
+#include <kern/task.h>
-#ifdef DEBUG
+#if DEBUG
#define DBG(x...) kprintf(x)
#else
#define DBG(x...)
#endif
+decl_simple_lock_data(,pmc_lock)
+static task_t pmc_owner = TASK_NULL;
+static int pmc_thread_count = 0;
+
+/* PMC Facility Owner:
+ * TASK_NULL - no one owns it
+ * kernel_task - owned by pmc
+ * other task - owned by another task
+ */
+
/*
* Table of ESCRs and addresses associated with performance counters/CCCRs.
* See Intel SDM Vol 3, Table 15-4 (section 15.9):
(*pmc_table->ovf_func[id])(id, state);
}
-int
-pmc_init(void)
+void *
+pmc_alloc(void)
{
int ret;
- cpu_core_t *my_core;
pmc_table_t *pmc_table;
pmc_machine_t pmc_type;
- my_core = cpu_core();
- assert(my_core);
-
pmc_type = _pmc_machine_type();
if (pmc_type == pmc_none) {
- return KERN_FAILURE;
+ return NULL;
}
- pmc_table = (pmc_table_t *) my_core->pmc;
- if (pmc_table == NULL) {
ret = kmem_alloc(kernel_map,
(void *) &pmc_table, sizeof(pmc_table_t));
if (ret != KERN_SUCCESS)
default:
break;
}
- if (!atomic_cmpxchg((uint32_t *) &my_core->pmc,
- 0, (uint32_t) pmc_table)) {
- kmem_free(kernel_map,
- (vm_offset_t) pmc_table, sizeof(pmc_table_t));
- }
- }
- DBG("pmc_init() done for cpu %d my_core->pmc=0x%x type=%d\n",
- cpu_number(), my_core->pmc, pmc_type);
-
- return KERN_SUCCESS;
+ return (void *) pmc_table;
}
+
static inline pmc_table_t *
pmc_table_valid(pmc_id_t id)
{
return KERN_SUCCESS;
}
+
+int
+pmc_acquire(task_t task)
+{
+ kern_return_t retval = KERN_SUCCESS;
+
+ simple_lock(&pmc_lock);
+
+ if(pmc_owner == task) {
+ DBG("pmc_acquire - "
+ "ACQUIRED: already owner\n");
+ retval = KERN_SUCCESS;
+ /* already own it */
+ } else if(pmc_owner == TASK_NULL) { /* no one owns it */
+ pmc_owner = task;
+ pmc_thread_count = 0;
+ DBG("pmc_acquire - "
+ "ACQUIRED: no current owner - made new owner\n");
+ retval = KERN_SUCCESS;
+ } else { /* someone already owns it */
+ if(pmc_owner == kernel_task) {
+ if(pmc_thread_count == 0) {
+ /* kernel owns it but no threads using it */
+ pmc_owner = task;
+ pmc_thread_count = 0;
+ DBG("pmc_acquire - "
+ "ACQUIRED: owned by kernel, no threads\n");
+ retval = KERN_SUCCESS;
+ } else {
+ DBG("pmc_acquire - "
+ "DENIED: owned by kernel, in use\n");
+ retval = KERN_RESOURCE_SHORTAGE;
+ }
+ } else { /* non-kernel owner */
+ DBG("pmc_acquire - "
+ "DENIED: owned by another task\n");
+ retval = KERN_RESOURCE_SHORTAGE;
+ }
+ }
+
+ simple_unlock(&pmc_lock);
+ return retval;
+}
+
+int
+pmc_release(task_t task)
+{
+ kern_return_t retval = KERN_SUCCESS;
+ task_t old_pmc_owner = pmc_owner;
+
+ simple_lock(&pmc_lock);
+
+ if(task != pmc_owner) {
+ retval = KERN_NO_ACCESS;
+ } else {
+ if(old_pmc_owner == kernel_task) {
+ if(pmc_thread_count>0) {
+ DBG("pmc_release - "
+ "NOT RELEASED: owned by kernel, in use\n");
+ retval = KERN_NO_ACCESS;
+ } else {
+ DBG("pmc_release - "
+ "RELEASED: was owned by kernel\n");
+ pmc_owner = TASK_NULL;
+ retval = KERN_SUCCESS;
+ }
+ } else {
+ DBG("pmc_release - "
+ "RELEASED: was owned by user\n");
+ pmc_owner = TASK_NULL;
+ retval = KERN_SUCCESS;
+ }
+ }
+
+ simple_unlock(&pmc_lock);
+ return retval;
+}
+
projects / apple / xnu.git / blobdiff