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-rw-r--r--src/cpu-exec-common.c82
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diff --git a/src/cpu-exec-common.c b/src/cpu-exec-common.c
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+/*
+ * emulator main execution loop
+ *
+ * Copyright (c) 2003-2005 Fabrice Bellard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+#include "cpu.h"
+#include "sysemu/cpus.h"
+#include "exec/memory-internal.h"
+
+bool exit_request;
+CPUState *tcg_current_cpu;
+
+/* exit the current TB from a signal handler. The host registers are
+ restored in a state compatible with the CPU emulator
+ */
+#if defined(CONFIG_SOFTMMU)
+void cpu_resume_from_signal(CPUState *cpu, void *puc)
+{
+ /* XXX: restore cpu registers saved in host registers */
+
+ cpu->exception_index = -1;
+ siglongjmp(cpu->jmp_env, 1);
+}
+
+void cpu_reloading_memory_map(void)
+{
+ if (qemu_in_vcpu_thread()) {
+ /* The guest can in theory prolong the RCU critical section as long
+ * as it feels like. The major problem with this is that because it
+ * can do multiple reconfigurations of the memory map within the
+ * critical section, we could potentially accumulate an unbounded
+ * collection of memory data structures awaiting reclamation.
+ *
+ * Because the only thing we're currently protecting with RCU is the
+ * memory data structures, it's sufficient to break the critical section
+ * in this callback, which we know will get called every time the
+ * memory map is rearranged.
+ *
+ * (If we add anything else in the system that uses RCU to protect
+ * its data structures, we will need to implement some other mechanism
+ * to force TCG CPUs to exit the critical section, at which point this
+ * part of this callback might become unnecessary.)
+ *
+ * This pair matches cpu_exec's rcu_read_lock()/rcu_read_unlock(), which
+ * only protects cpu->as->dispatch. Since we know our caller is about
+ * to reload it, it's safe to split the critical section.
+ */
+ rcu_read_unlock();
+ rcu_read_lock();
+ }
+}
+#endif
+
+void cpu_loop_exit(CPUState *cpu)
+{
+ cpu->current_tb = NULL;
+ siglongjmp(cpu->jmp_env, 1);
+}
+
+void cpu_loop_exit_restore(CPUState *cpu, uintptr_t pc)
+{
+ if (pc) {
+ cpu_restore_state(cpu, pc);
+ }
+ cpu->current_tb = NULL;
+ siglongjmp(cpu->jmp_env, 1);
+}
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