From a42cf3f3f266a97ceb13e8b99bc7b13f7bf4192a Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 27 Jan 2017 11:01:00 +0100 Subject: [PATCH] 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 --- cpu-exec.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/cpu-exec.c b/cpu-exec.c index ed2fbc6ed2..865015cd53 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -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