It's either "GNU *Library* General Public version 2" or "GNU Lesser General Public version *2.1*", but there was no "version 2.0" of the "Lesser" library. So assume that version 2.1 is meant here. Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <1548252536-6242-5-git-send-email-thuth@redhat.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
		
			
				
	
	
		
			84 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			84 lines
		
	
	
		
			2.8 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 2.1 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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#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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bool tcg_allowed;
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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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    cpu->exception_index = -1;
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    cpu_loop_exit(cpu);
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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() && current_cpu->running) {
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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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void cpu_loop_exit(CPUState *cpu)
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{
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    /* Undo the setting in cpu_tb_exec.  */
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    cpu->can_do_io = 1;
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    siglongjmp(cpu->jmp_env, 1);
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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, true);
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    }
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    cpu_loop_exit(cpu);
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}
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void cpu_loop_exit_atomic(CPUState *cpu, uintptr_t pc)
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{
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    cpu->exception_index = EXCP_ATOMIC;
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    cpu_loop_exit_restore(cpu, pc);
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}
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