Commit 225d02cd authored by Edgar E. Iglesias's avatar Edgar E. Iglesias
Browse files

Avoid deadlock whith iothread and icount 



When using the iothread together with icount, make sure the
qemu_icount counter makes forward progress when the vcpu is
idle to avoid deadlocks.

Signed-off-by: default avatarEdgar E. Iglesias <edgar.iglesias@gmail.com>
parent 5d0bb823

qemu-timer.c

+9 −6
Original line number Diff line number Diff line
@@ -110,7 +110,6 @@ static int64_t cpu_get_clock(void) 
    }

}



#ifndef CONFIG_IOTHREAD

static int64_t qemu_icount_delta(void)

{

    if (!use_icount) {
@@ -124,7 +123,6 @@ static int64_t qemu_icount_delta(void) 
        return cpu_get_icount() - cpu_get_clock();

    }

}

#endif



/* enable cpu_get_ticks() */

void cpu_enable_ticks(void)
@@ -1077,9 +1075,17 @@ void quit_timers(void) 


int qemu_calculate_timeout(void)

{

#ifndef CONFIG_IOTHREAD

    int timeout;



#ifdef CONFIG_IOTHREAD

    /* When using icount, making forward progress with qemu_icount when the

       guest CPU is idle is critical. We only use the static io-thread timeout

       for non icount runs.  */

    if (!use_icount) {

        return 1000;

    }

#endif



    if (!vm_running)

        timeout = 5000;

    else {
@@ -1110,8 +1116,5 @@ int qemu_calculate_timeout(void) 
    }



    return timeout;

#else /* CONFIG_IOTHREAD */

    return 1000;

#endif

}