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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_OSREFERENCE_LICENSE_HEADER_END@ */ /* * @OSF_COPYRIGHT@ */ /* * Mach Operating System * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University * All Rights Reserved. * * Permission to use, copy, modify and distribute this software and its * documentation is hereby granted, provided that both the copyright * notice and this permission notice appear in all copies of the * software, derivative works or modified versions, and any portions * thereof, and that both notices appear in supporting documentation. * * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. * * Carnegie Mellon requests users of this software to return to * * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU * School of Computer Science * Carnegie Mellon University * Pittsburgh PA 15213-3890 * * any improvements or extensions that they make and grant Carnegie Mellon * the rights to redistribute these changes. */ /* */ /* * * This file contains routines to check whether an ast is needed. * * ast_check() - check whether ast is needed for interrupt or context * switch. Usually called by clock interrupt handler. * */ #include <cputypes.h> #include <platforms.h> #include <kern/ast.h> #include <kern/counters.h> #include <kern/cpu_number.h> #include <kern/misc_protos.h> #include <kern/queue.h> #include <kern/sched_prim.h> #include <kern/thread.h> #include <kern/processor.h> #include <kern/spl.h> #include <kern/wait_queue.h> #include <kern/ledger.h> #include <mach/policy.h> #include <machine/trap.h> // for CHUD AST hook #include <machine/pal_routines.h> #include <security/mac_mach_internal.h> // for MACF AST hook volatile perfASTCallback perfASTHook; void ast_init(void) { } extern void chudxnu_thread_ast(thread_t); // XXX this should probably be in a header... /* * Called at splsched. */ void ast_taken( ast_t reasons, boolean_t enable ) { boolean_t preempt_trap = (reasons == AST_PREEMPTION); ast_t *myast = ast_pending(); thread_t thread = current_thread(); perfASTCallback perf_hook = perfASTHook; /* * CHUD hook - all threads including idle processor threads */ if (perf_hook) { if (*myast & AST_CHUD_ALL) { (*perf_hook)(reasons, myast); if (*myast == AST_NONE) return; } } else *myast &= ~AST_CHUD_ALL; reasons &= *myast; *myast &= ~reasons; /* * Handle ASTs for all threads * except idle processor threads. */ if (!(thread->state & TH_IDLE)) { /* * Check for urgent preemption. */ if ( (reasons & AST_URGENT) && wait_queue_assert_possible(thread) ) { if (reasons & AST_PREEMPT) { counter(c_ast_taken_block++); thread_block_reason(THREAD_CONTINUE_NULL, NULL, AST_PREEMPT | AST_URGENT); } reasons &= ~AST_PREEMPTION; } /* * The kernel preempt traps * skip all other ASTs. */ if (!preempt_trap) { ml_set_interrupts_enabled(enable); #ifdef MACH_BSD /* * Handle BSD hook. */ if (reasons & AST_BSD) { thread_ast_clear(thread, AST_BSD); bsd_ast(thread); } #endif #if CONFIG_MACF /* * Handle MACF hook. */ if (reasons & AST_MACF) { thread_ast_clear(thread, AST_MACF); mac_thread_userret(thread); } #endif /* * Thread APC hook. */ if (reasons & AST_APC) act_execute_returnhandlers(); if (reasons & AST_LEDGER) { thread_ast_clear(thread, AST_LEDGER); ledger_ast(thread); } /* * Kernel Profiling Hook */ if (reasons & AST_KPERF) { thread_ast_clear(thread, AST_KPERF); chudxnu_thread_ast(thread); } ml_set_interrupts_enabled(FALSE); /* * Check for preemption. */ if (reasons & AST_PREEMPT) reasons = csw_check(current_processor()); if ( (reasons & AST_PREEMPT) && wait_queue_assert_possible(thread) ) { counter(c_ast_taken_block++); thread_block_reason((thread_continue_t)thread_exception_return, NULL, AST_PREEMPT); } } } ml_set_interrupts_enabled(enable); } /* * Called at splsched. */ void ast_check( processor_t processor) { thread_t thread = processor->active_thread; processor->current_pri = thread->sched_pri; processor->current_thmode = thread->sched_mode; if ( processor->state == PROCESSOR_RUNNING || processor->state == PROCESSOR_SHUTDOWN ) { ast_t preempt; /* * Propagate thread ast to processor. */ pal_ast_check(thread); ast_propagate(thread->ast); /* * Context switch check. */ if ((preempt = csw_check(processor)) != AST_NONE) ast_on(preempt); } }