qemu-patch-raspberry4/stubs/iothread-lock.c

#include "qemu-common.h"
#include "qemu/main-loop.h"

bool qemu_mutex_iothread_locked(void)
{
    return true;
}

void qemu_mutex_lock_iothread(void)
{
}

void qemu_mutex_unlock_iothread(void)
{
}
stubs: fully replace qemu-tool.c and qemu-user.c Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> 2012-11-26 15:36:40 +01:00			`#include "qemu-common.h"`
			`#include "qemu/main-loop.h"`

main-loop: introduce qemu_mutex_iothread_locked This function will be used to avoid recursive locking of the iothread lock whenever address_space_rw/ld/st are called with the BQL held, which is almost always the case. Tracking whether the iothread is owned is very cheap (just use a TLS variable) but requires some care because now the lock must always be taken with qemu_mutex_lock_iothread(). Previously this wasn't the case. Outside TCG mode this is not a problem. In TCG mode, we need to be careful and avoid the "prod out of compiled code" step if already in a VCPU thread. This is easily done with a check on current_cpu, i.e. qemu_in_vcpu_thread(). Hopefully, multithreaded TCG will get rid of the whole logic to kick VCPUs whenever an I/O event occurs! Cc: Frederic Konrad <fred.konrad@greensocs.com> Message-Id: <1434646046-27150-3-git-send-email-pbonzini@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> 2015-06-18 18:47:19 +02:00			`bool qemu_mutex_iothread_locked(void)`
			`{`
			`return true;`
			`}`

stubs: fully replace qemu-tool.c and qemu-user.c Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> 2012-11-26 15:36:40 +01:00			`void qemu_mutex_lock_iothread(void)`
			`{`
			`}`

			`void qemu_mutex_unlock_iothread(void)`
			`{`
			`}`