aboutsummaryrefslogtreecommitdiff
path: root/cpu-exec.c
diff options
context:
space:
mode:
Diffstat (limited to 'cpu-exec.c')
-rw-r--r--cpu-exec.c83
1 files changed, 55 insertions, 28 deletions
diff --git a/cpu-exec.c b/cpu-exec.c
index 7db959c821..d04dd91ebd 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -29,6 +29,7 @@
#include "qemu/rcu.h"
#include "exec/tb-hash.h"
#include "exec/log.h"
+#include "qemu/main-loop.h"
#if defined(TARGET_I386) && !defined(CONFIG_USER_ONLY)
#include "hw/i386/apic.h"
#endif
@@ -221,20 +222,43 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles,
static void cpu_exec_step(CPUState *cpu)
{
+ CPUClass *cc = CPU_GET_CLASS(cpu);
CPUArchState *env = (CPUArchState *)cpu->env_ptr;
TranslationBlock *tb;
target_ulong cs_base, pc;
uint32_t flags;
cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags);
- tb = tb_gen_code(cpu, pc, cs_base, flags,
- 1 | CF_NOCACHE | CF_IGNORE_ICOUNT);
- tb->orig_tb = NULL;
- /* execute the generated code */
- trace_exec_tb_nocache(tb, pc);
- cpu_tb_exec(cpu, tb);
- tb_phys_invalidate(tb, -1);
- tb_free(tb);
+ if (sigsetjmp(cpu->jmp_env, 0) == 0) {
+ mmap_lock();
+ tb_lock();
+ tb = tb_gen_code(cpu, pc, cs_base, flags,
+ 1 | CF_NOCACHE | CF_IGNORE_ICOUNT);
+ tb->orig_tb = NULL;
+ tb_unlock();
+ mmap_unlock();
+
+ cc->cpu_exec_enter(cpu);
+ /* execute the generated code */
+ trace_exec_tb_nocache(tb, pc);
+ cpu_tb_exec(cpu, tb);
+ cc->cpu_exec_exit(cpu);
+
+ tb_lock();
+ tb_phys_invalidate(tb, -1);
+ tb_free(tb);
+ tb_unlock();
+ } else {
+ /* We may have exited due to another problem here, so we need
+ * to reset any tb_locks we may have taken but didn't release.
+ * The mmap_lock is dropped by tb_gen_code if it runs out of
+ * memory.
+ */
+#ifndef CONFIG_SOFTMMU
+ tcg_debug_assert(!have_mmap_lock());
+#endif
+ tb_lock_reset();
+ }
}
void cpu_exec_step_atomic(CPUState *cpu)
@@ -378,12 +402,13 @@ static inline bool cpu_handle_halt(CPUState *cpu)
if ((cpu->interrupt_request & CPU_INTERRUPT_POLL)
&& replay_interrupt()) {
X86CPU *x86_cpu = X86_CPU(cpu);
+ qemu_mutex_lock_iothread();
apic_poll_irq(x86_cpu->apic_state);
cpu_reset_interrupt(cpu, CPU_INTERRUPT_POLL);
+ qemu_mutex_unlock_iothread();
}
#endif
if (!cpu_has_work(cpu)) {
- current_cpu = NULL;
return true;
}
@@ -433,7 +458,9 @@ static inline bool cpu_handle_exception(CPUState *cpu, int *ret)
#else
if (replay_exception()) {
CPUClass *cc = CPU_GET_CLASS(cpu);
+ qemu_mutex_lock_iothread();
cc->do_interrupt(cpu);
+ qemu_mutex_unlock_iothread();
cpu->exception_index = -1;
} else if (!replay_has_interrupt()) {
/* give a chance to iothread in replay mode */
@@ -459,9 +486,11 @@ static inline bool cpu_handle_interrupt(CPUState *cpu,
TranslationBlock **last_tb)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
- int interrupt_request = cpu->interrupt_request;
- if (unlikely(interrupt_request)) {
+ if (unlikely(atomic_read(&cpu->interrupt_request))) {
+ int interrupt_request;
+ qemu_mutex_lock_iothread();
+ interrupt_request = cpu->interrupt_request;
if (unlikely(cpu->singlestep_enabled & SSTEP_NOIRQ)) {
/* Mask out external interrupts for this step. */
interrupt_request &= ~CPU_INTERRUPT_SSTEP_MASK;
@@ -469,6 +498,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu,
if (interrupt_request & CPU_INTERRUPT_DEBUG) {
cpu->interrupt_request &= ~CPU_INTERRUPT_DEBUG;
cpu->exception_index = EXCP_DEBUG;
+ qemu_mutex_unlock_iothread();
return true;
}
if (replay_mode == REPLAY_MODE_PLAY && !replay_has_interrupt()) {
@@ -478,6 +508,7 @@ static inline bool cpu_handle_interrupt(CPUState *cpu,
cpu->interrupt_request &= ~CPU_INTERRUPT_HALT;
cpu->halted = 1;
cpu->exception_index = EXCP_HLT;
+ qemu_mutex_unlock_iothread();
return true;
}
#if defined(TARGET_I386)
@@ -488,12 +519,14 @@ static inline bool cpu_handle_interrupt(CPUState *cpu,
cpu_svm_check_intercept_param(env, SVM_EXIT_INIT, 0, 0);
do_cpu_init(x86_cpu);
cpu->exception_index = EXCP_HALTED;
+ qemu_mutex_unlock_iothread();
return true;
}
#else
else if (interrupt_request & CPU_INTERRUPT_RESET) {
replay_interrupt();
cpu_reset(cpu);
+ qemu_mutex_unlock_iothread();
return true;
}
#endif
@@ -516,6 +549,9 @@ static inline bool cpu_handle_interrupt(CPUState *cpu,
the program flow was changed */
*last_tb = NULL;
}
+
+ /* If we exit via cpu_loop_exit/longjmp it is reset in cpu_exec */
+ qemu_mutex_unlock_iothread();
}
/* Finally, check if we need to exit to the main loop. */
@@ -548,13 +584,11 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb,
insns_left = atomic_read(&cpu->icount_decr.u32);
atomic_set(&cpu->icount_decr.u16.high, 0);
if (insns_left < 0) {
- /* Something asked us to stop executing
- * chained TBs; just continue round the main
- * loop. Whatever requested the exit will also
- * have set something else (eg exit_request or
- * interrupt_request) which we will handle
- * next time around the loop. But we need to
- * ensure the zeroing of tcg_exit_req (see cpu_tb_exec)
+ /* Something asked us to stop executing chained TBs; just
+ * continue round the main loop. Whatever requested the exit
+ * will also have set something else (eg exit_request or
+ * interrupt_request) which we will handle next time around
+ * the loop. But we need to ensure the zeroing of icount_decr
* comes before the next read of cpu->exit_request
* or cpu->interrupt_request.
*/
@@ -597,13 +631,8 @@ int cpu_exec(CPUState *cpu)
return EXCP_HALTED;
}
- atomic_mb_set(&tcg_current_cpu, cpu);
rcu_read_lock();
- if (unlikely(atomic_mb_read(&exit_request))) {
- cpu->exit_request = 1;
- }
-
cc->cpu_exec_enter(cpu);
/* Calculate difference between guest clock and host clock.
@@ -629,6 +658,9 @@ int cpu_exec(CPUState *cpu)
#endif /* buggy compiler */
cpu->can_do_io = 1;
tb_lock_reset();
+ if (qemu_mutex_iothread_locked()) {
+ qemu_mutex_unlock_iothread();
+ }
}
/* if an exception is pending, we execute it here */
@@ -648,10 +680,5 @@ int cpu_exec(CPUState *cpu)
cc->cpu_exec_exit(cpu);
rcu_read_unlock();
- /* fail safe : never use current_cpu outside cpu_exec() */
- current_cpu = NULL;
-
- /* Does not need atomic_mb_set because a spurious wakeup is okay. */
- atomic_set(&tcg_current_cpu, NULL);
return ret;
}