From: Dexuan Cui <decui@microsoft.com>
To: "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
Stephen Hemminger <sthemmin@microsoft.com>,
Sasha Levin <Alexander.Levin@microsoft.com>,
"sashal@kernel.org" <sashal@kernel.org>,
Haiyang Zhang <haiyangz@microsoft.com>,
KY Srinivasan <kys@microsoft.com>,
Michael Kelley <mikelley@microsoft.com>,
"tglx@linutronix.de" <tglx@linutronix.de>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Dexuan Cui <decui@microsoft.com>
Subject: [PATCH v3 05/12] Drivers: hv: vmbus: Suspend/resume the synic for hibernation
Date: Tue, 20 Aug 2019 01:52:02 +0000 [thread overview]
Message-ID: <1566265863-21252-6-git-send-email-decui@microsoft.com> (raw)
In-Reply-To: <1566265863-21252-1-git-send-email-decui@microsoft.com>
This is needed when we resume the old kernel from the "current" kernel.
Note: when hv_synic_suspend() and hv_synic_resume() run, all the
non-boot CPUs have been offlined, and interrupts are disabled on CPU0.
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
---
drivers/hv/vmbus_drv.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index ebd35fc..2ef375c 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -30,6 +30,7 @@
#include <linux/kdebug.h>
#include <linux/efi.h>
#include <linux/random.h>
+#include <linux/syscore_ops.h>
#include <clocksource/hyperv_timer.h>
#include "hyperv_vmbus.h"
@@ -2086,6 +2087,47 @@ static void hv_crash_handler(struct pt_regs *regs)
hyperv_cleanup();
};
+static int hv_synic_suspend(void)
+{
+ /*
+ * When we reach here, all the non-boot CPUs have been offlined, and
+ * the stimers on them have been unbound in hv_synic_cleanup() ->
+ * hv_stimer_cleanup() -> clockevents_unbind_device().
+ *
+ * hv_synic_suspend() only runs on CPU0 with interrupts disabled. Here
+ * we do not unbind the stimer on CPU0 because: 1) it's unnecessary
+ * because the interrupts remain disabled between syscore_suspend()
+ * and syscore_resume(): see create_image() and resume_target_kernel();
+ * 2) the stimer on CPU0 is automatically disabled later by
+ * syscore_suspend() -> timekeeping_suspend() -> tick_suspend() -> ...
+ * -> clockevents_shutdown() -> ... -> hv_ce_shutdown(); 3) a warning
+ * would be triggered if we call clockevents_unbind_device(), which
+ * may sleep, in an interrupts-disabled context. So, we intentionally
+ * don't call hv_stimer_cleanup(0) here.
+ */
+
+ hv_synic_disable_regs(0);
+
+ return 0;
+}
+
+static void hv_synic_resume(void)
+{
+ hv_synic_enable_regs(0);
+
+ /*
+ * Note: we don't need to call hv_stimer_init(0), because the timer
+ * on CPU0 is not unbound in hv_synic_suspend(), and the timer is
+ * automatically re-enabled in timekeeping_resume().
+ */
+}
+
+/* The callbacks run only on CPU0, with irqs_disabled. */
+static struct syscore_ops hv_synic_syscore_ops = {
+ .suspend = hv_synic_suspend,
+ .resume = hv_synic_resume,
+};
+
static int __init hv_acpi_init(void)
{
int ret, t;
@@ -2116,6 +2158,8 @@ static int __init hv_acpi_init(void)
hv_setup_kexec_handler(hv_kexec_handler);
hv_setup_crash_handler(hv_crash_handler);
+ register_syscore_ops(&hv_synic_syscore_ops);
+
return 0;
cleanup:
@@ -2128,6 +2172,8 @@ static void __exit vmbus_exit(void)
{
int cpu;
+ unregister_syscore_ops(&hv_synic_syscore_ops);
+
hv_remove_kexec_handler();
hv_remove_crash_handler();
vmbus_connection.conn_state = DISCONNECTED;
--
1.8.3.1
next prev parent reply other threads:[~2019-08-20 1:52 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-20 1:51 [PATCH v3 00/12] Enhance the hv_vmbus driver to support hibernation Dexuan Cui
2019-08-20 1:51 ` [PATCH v3 01/12] x86/hyper-v: Suspend/resume the hypercall page for hibernation Dexuan Cui
2019-08-20 1:51 ` [PATCH v3 02/12] x86/hyper-v: Implement hv_is_hibernation_supported() Dexuan Cui
2019-08-23 19:50 ` Michael Kelley
2019-08-30 23:37 ` Dexuan Cui
2019-08-20 1:52 ` [PATCH v3 03/12] clocksource/drivers: Suspend/resume Hyper-V clocksource for hibernation Dexuan Cui
2019-08-20 1:52 ` [PATCH v3 04/12] Drivers: hv: vmbus: Break out synic enable and disable operations Dexuan Cui
2019-08-20 1:52 ` Dexuan Cui [this message]
2019-08-20 1:52 ` [PATCH v3 06/12] Drivers: hv: vmbus: Add a helper function is_sub_channel() Dexuan Cui
2019-08-23 19:51 ` Michael Kelley
2019-08-20 1:52 ` [PATCH v3 07/12] Drivers: hv: vmbus: Implement suspend/resume for VSC drivers for hibernation Dexuan Cui
2019-08-20 1:52 ` [PATCH v3 08/12] Drivers: hv: vmbus: Ignore the offers when resuming from hibernation Dexuan Cui
2019-08-23 19:56 ` Michael Kelley
2019-08-31 0:23 ` Dexuan Cui
2019-08-20 1:52 ` [PATCH v3 09/12] Drivers: hv: vmbus: Suspend/resume the vmbus itself for hibernation Dexuan Cui
2019-08-20 1:52 ` [PATCH v3 10/12] Drivers: hv: vmbus: Clean up hv_sock channels by force upon suspend Dexuan Cui
2019-08-23 20:02 ` Michael Kelley
2019-08-31 2:00 ` Dexuan Cui
2019-08-20 1:52 ` [PATCH v3 11/12] Drivers: hv: vmbus: Suspend after cleaning up hv_sock and sub channels Dexuan Cui
2019-08-23 20:16 ` Michael Kelley
2019-08-31 2:54 ` Dexuan Cui
2019-08-20 1:52 ` [PATCH v3 12/12] Drivers: hv: vmbus: Resume after fixing up old primary channels Dexuan Cui
2019-08-23 20:25 ` Michael Kelley
2019-08-31 4:37 ` Dexuan Cui
2019-08-31 5:08 ` Dexuan Cui
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1566265863-21252-6-git-send-email-decui@microsoft.com \
--to=decui@microsoft.com \
--cc=Alexander.Levin@microsoft.com \
--cc=gregkh@linuxfoundation.org \
--cc=haiyangz@microsoft.com \
--cc=kys@microsoft.com \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mikelley@microsoft.com \
--cc=sashal@kernel.org \
--cc=sthemmin@microsoft.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).