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From 5e18df4d60ba22586ec4f4d80804ee8d4e41372e Mon Sep 17 00:00:00 2001
From: Stefan Hajnoczi <stefanha@redhat.com>
Date: Thu, 23 Oct 2014 10:03:09 +0200
Subject: [PATCH 01/16] trace: add qemu_system_powerdown_request and
 qemu_system_shutdown_request trace events

Message-id: <1414058589-12881-1-git-send-email-stefanha@redhat.com>
Patchwork-id: 61833
O-Subject: [RHEL7.2 qemu-kvm PATCH] trace: add qemu_system_powerdown_request and qemu_system_shutdown_request trace events
Bugzilla: 1155671
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
RH-Acked-by: Amos Kong <akong@redhat.com>
RH-Acked-by: Markus Armbruster <armbru@redhat.com>

From: Yang Zhiyong <yangzy.fnst@cn.fujitsu.com>

Bugzilla: 1155671
Brew: https://brewweb.devel.redhat.com/taskinfo?taskID=8153235
Upstream: merged

We have the experience that the guest doesn't stop successfully
though it was instructed to shut down.

The root cause may be not in QEMU mostly.  However, QEMU is often
suspected at the beginning just because the issue occurred in
virtualization environment.

Therefore, we need to affirm that QEMU received the shutdown
request and raised ACPI irq from "virsh shutdown" command,
virt-manger or stopping QEMU process to the VM .
So that we can affirm the problems was belonged to the Guset OS
rather than the QEMU itself.

When we stop guests by "virsh shutdown" command or virt-manger,
or stopping QEMU process, qemu_system_powerdown_request() or
qemu_system_shutdown_request() is called. Then the below functions
in main_loop_should_exit() of Vl.c are called roughly in the
following order.

	if (qemu_powerdown_requested())
		qemu_system_powerdown()
			monitor_protocol_event(QEVENT_POWERDOWN, NULL)

	OR

	if(qemu_shutdown_requested()}
		monitor_protocol_event(QEVENT_SHUTDOWN, NULL);

The tracepoint of monitor_protocol_event() already exists, but no
tracepoints are defined for qemu_system_powerdown_request() and
qemu_system_shutdown_request(). So this patch adds two tracepoints for
the two functions. We believe that it will become much easier to
isolate the problem mentioned above by these tracepoints.

Signed-off-by: Yang Zhiyong <yangzy.fnst@cn.fujitsu.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
(cherry picked from commit bc78cff9757782501db15d39828e6af4186fe331)
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

Conflicts:
	trace-events

Context conflict, easy to resolve.
---
 trace-events | 2 ++
 vl.c         | 2 ++
 2 files changed, 4 insertions(+)
---
 trace-events | 2 ++
 vl.c         | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/trace-events b/trace-events
index e7bb7e0..b43132c 100644
--- a/trace-events
+++ b/trace-events
@@ -477,6 +477,8 @@ runstate_set(int new_state) "new state %d"
 g_malloc(size_t size, void *ptr) "size %zu ptr %p"
 g_realloc(void *ptr, size_t size, void *newptr) "ptr %p size %zu newptr %p"
 g_free(void *ptr) "ptr %p"
+qemu_system_shutdown_request(void) ""
+qemu_system_powerdown_request(void) ""
 
 # block/qcow2.c
 qcow2_writev_start_req(void *co, int64_t sector, int nb_sectors) "co %p sector %" PRIx64 " nb_sectors %d"
diff --git a/vl.c b/vl.c
index 2932d7c..2b3dc88 100644
--- a/vl.c
+++ b/vl.c
@@ -1894,6 +1894,7 @@ void qemu_system_killed(int signal, pid_t pid)
 
 void qemu_system_shutdown_request(void)
 {
+    trace_qemu_system_shutdown_request();
     shutdown_requested = 1;
     qemu_notify_event();
 }
@@ -1906,6 +1907,7 @@ static void qemu_system_powerdown(void)
 
 void qemu_system_powerdown_request(void)
 {
+    trace_qemu_system_powerdown_request();
     powerdown_requested = 1;
     qemu_notify_event();
 }
-- 
1.8.3.1