* [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread
@ 2017-05-03 7:28 Fam Zheng
2017-05-03 7:42 ` Fam Zheng
2017-05-04 12:59 ` Paolo Bonzini
0 siblings, 2 replies; 5+ messages in thread
From: Fam Zheng @ 2017-05-03 7:28 UTC (permalink / raw)
To: qemu-devel; +Cc: pbonzini, armbru, peterx
This fixes an assertion failure in the following backtrace:
__GI___assert_fail
memory_region_transaction_commit
memory_region_add_eventfd
virtio_pci_ioeventfd_assign
virtio_bus_set_host_notifier
virtio_blk_data_plane_start
virtio_bus_start_ioeventfd
virtio_vmstate_change
vm_state_notify
vm_prepare_start
vm_start
dump_cleanup
dump_process
dump_thread
start_thread
clone
vm_start need BQL, acquire it if doing cleaning up from main thread.
Signed-off-by: Fam Zheng <famz@redhat.com>
---
dump.c | 7 +++++++
include/sysemu/dump.h | 1 +
2 files changed, 8 insertions(+)
diff --git a/dump.c b/dump.c
index f7b80d8..d9090a2 100644
--- a/dump.c
+++ b/dump.c
@@ -77,7 +77,13 @@ static int dump_cleanup(DumpState *s)
memory_mapping_list_free(&s->list);
close(s->fd);
if (s->resume) {
+ if (s->detached) {
+ qemu_mutex_lock_iothread();
+ }
vm_start();
+ if (s->detached) {
+ qemu_mutex_unlock_iothread();
+ }
}
return 0;
@@ -1804,6 +1810,7 @@ void qmp_dump_guest_memory(bool paging, const char *file,
if (detach_p) {
/* detached dump */
+ s->detached = true;
qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread,
s, QEMU_THREAD_DETACHED);
} else {
diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h
index ef931be..2672a15 100644
--- a/include/sysemu/dump.h
+++ b/include/sysemu/dump.h
@@ -157,6 +157,7 @@ typedef struct DumpState {
uint32_t sh_info;
bool have_section;
bool resume;
+ bool detached;
ssize_t note_size;
hwaddr memory_offset;
int fd;
--
2.9.3
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread
2017-05-03 7:28 [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread Fam Zheng
@ 2017-05-03 7:42 ` Fam Zheng
2017-05-03 8:37 ` Marc-André Lureau
2017-05-04 12:59 ` Paolo Bonzini
1 sibling, 1 reply; 5+ messages in thread
From: Fam Zheng @ 2017-05-03 7:42 UTC (permalink / raw)
To: qemu-devel; +Cc: pbonzini, armbru, peterx
On Wed, 05/03 15:28, Fam Zheng wrote:
> This fixes an assertion failure in the following backtrace:
>
> __GI___assert_fail
> memory_region_transaction_commit
> memory_region_add_eventfd
> virtio_pci_ioeventfd_assign
> virtio_bus_set_host_notifier
> virtio_blk_data_plane_start
> virtio_bus_start_ioeventfd
> virtio_vmstate_change
> vm_state_notify
> vm_prepare_start
> vm_start
> dump_cleanup
> dump_process
> dump_thread
> start_thread
> clone
>
> vm_start need BQL, acquire it if doing cleaning up from main thread.
Oops, s/need/needs and s/main thread/detached thread/.
Fam
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread
2017-05-03 7:42 ` Fam Zheng
@ 2017-05-03 8:37 ` Marc-André Lureau
2017-05-04 12:58 ` Paolo Bonzini
0 siblings, 1 reply; 5+ messages in thread
From: Marc-André Lureau @ 2017-05-03 8:37 UTC (permalink / raw)
To: Fam Zheng, qemu-devel; +Cc: pbonzini, armbru, peterx
Hi
On Wed, May 3, 2017 at 11:42 AM Fam Zheng <famz@redhat.com> wrote:
> On Wed, 05/03 15:28, Fam Zheng wrote:
> > This fixes an assertion failure in the following backtrace:
> >
>
Do you know if it's a regression? Is this a racy case? (I couldn't
reproduce)
> > __GI___assert_fail
> > memory_region_transaction_commit
> > memory_region_add_eventfd
> > virtio_pci_ioeventfd_assign
> > virtio_bus_set_host_notifier
> > virtio_blk_data_plane_start
> > virtio_bus_start_ioeventfd
> > virtio_vmstate_change
> > vm_state_notify
> > vm_prepare_start
> > vm_start
> > dump_cleanup
> > dump_process
> > dump_thread
> > start_thread
> > clone
> >
> > vm_start need BQL, acquire it if doing cleaning up from main thread.
>
> Oops, s/need/needs and s/main thread/detached thread/.
>
With that fixed,
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
--
Marc-André Lureau
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread
2017-05-03 8:37 ` Marc-André Lureau
@ 2017-05-04 12:58 ` Paolo Bonzini
0 siblings, 0 replies; 5+ messages in thread
From: Paolo Bonzini @ 2017-05-04 12:58 UTC (permalink / raw)
To: Marc-André Lureau, Fam Zheng, qemu-devel; +Cc: armbru, peterx
On 03/05/2017 10:37, Marc-André Lureau wrote:
> Hi
>
> On Wed, May 3, 2017 at 11:42 AM Fam Zheng <famz@redhat.com
> <mailto:famz@redhat.com>> wrote:
>
> On Wed, 05/03 15:28, Fam Zheng wrote:
> > This fixes an assertion failure in the following backtrace:
>
> Do you know if it's a regression? Is this a racy case? (I couldn't
> reproduce)
I think it's never worked since separate-thread dump was introduced.
Paolo
>
> > __GI___assert_fail
> > memory_region_transaction_commit
> > memory_region_add_eventfd
> > virtio_pci_ioeventfd_assign
> > virtio_bus_set_host_notifier
> > virtio_blk_data_plane_start
> > virtio_bus_start_ioeventfd
> > virtio_vmstate_change
> > vm_state_notify
> > vm_prepare_start
> > vm_start
> > dump_cleanup
> > dump_process
> > dump_thread
> > start_thread
> > clone
> >
> > vm_start need BQL, acquire it if doing cleaning up from main thread.
>
> Oops, s/need/needs and s/main thread/detached thread/.
>
>
> With that fixed,
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com
> <mailto:marcandre.lureau@redhat.com>>
>
> --
> Marc-André Lureau
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread
2017-05-03 7:28 [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread Fam Zheng
2017-05-03 7:42 ` Fam Zheng
@ 2017-05-04 12:59 ` Paolo Bonzini
1 sibling, 0 replies; 5+ messages in thread
From: Paolo Bonzini @ 2017-05-04 12:59 UTC (permalink / raw)
To: Fam Zheng, qemu-devel; +Cc: armbru, peterx
On 03/05/2017 09:28, Fam Zheng wrote:
> This fixes an assertion failure in the following backtrace:
>
> __GI___assert_fail
> memory_region_transaction_commit
> memory_region_add_eventfd
> virtio_pci_ioeventfd_assign
> virtio_bus_set_host_notifier
> virtio_blk_data_plane_start
> virtio_bus_start_ioeventfd
> virtio_vmstate_change
> vm_state_notify
> vm_prepare_start
> vm_start
> dump_cleanup
> dump_process
> dump_thread
> start_thread
> clone
>
> vm_start need BQL, acquire it if doing cleaning up from main thread.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
> dump.c | 7 +++++++
> include/sysemu/dump.h | 1 +
> 2 files changed, 8 insertions(+)
>
> diff --git a/dump.c b/dump.c
> index f7b80d8..d9090a2 100644
> --- a/dump.c
> +++ b/dump.c
> @@ -77,7 +77,13 @@ static int dump_cleanup(DumpState *s)
> memory_mapping_list_free(&s->list);
> close(s->fd);
> if (s->resume) {
> + if (s->detached) {
> + qemu_mutex_lock_iothread();
> + }
> vm_start();
> + if (s->detached) {
> + qemu_mutex_unlock_iothread();
> + }
> }
>
> return 0;
> @@ -1804,6 +1810,7 @@ void qmp_dump_guest_memory(bool paging, const char *file,
>
> if (detach_p) {
> /* detached dump */
> + s->detached = true;
> qemu_thread_create(&s->dump_thread, "dump_thread", dump_thread,
> s, QEMU_THREAD_DETACHED);
> } else {
> diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h
> index ef931be..2672a15 100644
> --- a/include/sysemu/dump.h
> +++ b/include/sysemu/dump.h
> @@ -157,6 +157,7 @@ typedef struct DumpState {
> uint32_t sh_info;
> bool have_section;
> bool resume;
> + bool detached;
> ssize_t note_size;
> hwaddr memory_offset;
> int fd;
>
Queued, thanks.
Paolo
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2017-05-04 12:59 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-05-03 7:28 [Qemu-devel] [PATCH] dump: Acquire BQL around vm_start() in dump thread Fam Zheng
2017-05-03 7:42 ` Fam Zheng
2017-05-03 8:37 ` Marc-André Lureau
2017-05-04 12:58 ` Paolo Bonzini
2017-05-04 12:59 ` Paolo Bonzini
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).