cpu-exec: avoid repeated sigsetjmp on interrupts

The sigsetjmp only needs to be prepared once for the whole execution
of cpu_exec.  This patch takes care of the "== 0" side, using a
nested loop so that cpu_handle_interrupt goes straight back to
cpu_handle_exception without doing another sigsetjmp.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2017-01-27 11:01:00 +01:00
parent 209b71b60e
commit a42cf3f3f2
1 changed files with 12 additions and 12 deletions

View File

@ -627,21 +627,21 @@ int cpu_exec(CPUState *cpu)
for(;;) {
/* prepare setjmp context for exception handling */
if (sigsetjmp(cpu->jmp_env, 0) == 0) {
TranslationBlock *last_tb = NULL;
int tb_exit = 0;
/* if an exception is pending, we execute it here */
if (cpu_handle_exception(cpu, &ret)) {
break;
}
while (!cpu_handle_exception(cpu, &ret)) {
TranslationBlock *last_tb = NULL;
int tb_exit = 0;
while (!cpu_handle_interrupt(cpu, &last_tb)) {
TranslationBlock *tb = tb_find(cpu, last_tb, tb_exit);
cpu_loop_exec_tb(cpu, tb, &last_tb, &tb_exit, &sc);
/* Try to align the host and virtual clocks
if the guest is in advance */
align_clocks(&sc, cpu);
while (!cpu_handle_interrupt(cpu, &last_tb)) {
TranslationBlock *tb = tb_find(cpu, last_tb, tb_exit);
cpu_loop_exec_tb(cpu, tb, &last_tb, &tb_exit, &sc);
/* Try to align the host and virtual clocks
if the guest is in advance */
align_clocks(&sc, cpu);
}
}
break;
} else {
#if defined(__clang__) || !QEMU_GNUC_PREREQ(4, 6)
/* Some compilers wrongly smash all local variables after