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		6886b98036
		
	
	
	
	
		
			
			The function cpu_resume_from_signal() is now always called with a NULL puc argument, and is rather misnamed since it is never called from a signal handler. It is essentially forcing an exit to the top level cpu loop but without raising any exception, so rename it to cpu_loop_exit_noexc() and drop the useless unused argument. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org> Acked-by: Eduardo Habkost <ehabkost@redhat.com> Acked-by: Riku Voipio <riku.voipio@linaro.org> Message-id: 1463494687-25947-4-git-send-email-peter.maydell@linaro.org
		
			
				
	
	
		
			80 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  emulator main execution loop
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|  *
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|  *  Copyright (c) 2003-2005 Fabrice Bellard
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|  *
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|  * This library is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2 of the License, or (at your option) any later version.
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|  *
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|  * This library is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
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|  */
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| 
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| #include "qemu/osdep.h"
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| #include "cpu.h"
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| #include "sysemu/cpus.h"
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| #include "exec/exec-all.h"
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| #include "exec/memory-internal.h"
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| 
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| bool exit_request;
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| CPUState *tcg_current_cpu;
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| 
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| /* exit the current TB, but without causing any exception to be raised */
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| void cpu_loop_exit_noexc(CPUState *cpu)
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| {
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|     /* XXX: restore cpu registers saved in host registers */
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| 
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|     cpu->exception_index = -1;
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|     siglongjmp(cpu->jmp_env, 1);
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| }
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| 
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| #if defined(CONFIG_SOFTMMU)
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| void cpu_reloading_memory_map(void)
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| {
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|     if (qemu_in_vcpu_thread()) {
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|         /* The guest can in theory prolong the RCU critical section as long
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|          * as it feels like. The major problem with this is that because it
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|          * can do multiple reconfigurations of the memory map within the
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|          * critical section, we could potentially accumulate an unbounded
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|          * collection of memory data structures awaiting reclamation.
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|          *
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|          * Because the only thing we're currently protecting with RCU is the
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|          * memory data structures, it's sufficient to break the critical section
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|          * in this callback, which we know will get called every time the
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|          * memory map is rearranged.
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|          *
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|          * (If we add anything else in the system that uses RCU to protect
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|          * its data structures, we will need to implement some other mechanism
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|          * to force TCG CPUs to exit the critical section, at which point this
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|          * part of this callback might become unnecessary.)
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|          *
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|          * This pair matches cpu_exec's rcu_read_lock()/rcu_read_unlock(), which
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|          * only protects cpu->as->dispatch. Since we know our caller is about
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|          * to reload it, it's safe to split the critical section.
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|          */
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|         rcu_read_unlock();
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|         rcu_read_lock();
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|     }
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| }
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| #endif
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| 
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| void cpu_loop_exit(CPUState *cpu)
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| {
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|     siglongjmp(cpu->jmp_env, 1);
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| }
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| 
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| void cpu_loop_exit_restore(CPUState *cpu, uintptr_t pc)
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| {
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|     if (pc) {
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|         cpu_restore_state(cpu, pc);
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|     }
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|     siglongjmp(cpu->jmp_env, 1);
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| }
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