* [PATCH v3 2/5] xen: use freeze/restore/thaw PM events for suspend/resume/chkpt
@ 2011-03-12 5:07 Shriram Rajagopalan
2011-03-16 17:19 ` [PATCH v4 " Shriram Rajagopalan
0 siblings, 1 reply; 4+ messages in thread
From: Shriram Rajagopalan @ 2011-03-12 5:07 UTC (permalink / raw)
To: xen-devel; +Cc: rjw, Shriram Rajagopalan, linux-pm
Use PM_FREEZE, PM_THAW and PM_RESTORE power events for
suspend/resume/checkpoint functionality, instead of PM_SUSPEND
and PM_RESUME. Use of these pm events fixes the Xen Guest hangup
when taking checkpoints. When a suspend event is cancelled
(while taking checkpoints once/continuously), we use PM_THAW
instead of PM_RESUME. PM_RESTORE is used when suspend is not
cancelled. See Documentation/power/devices.txt and linux/pm.h
for more info about freeze, thaw and restore. The sequence of
pm events in a suspend-resume scenario is shown below.
dpm_suspend_start(PMSG_FREEZE);
dpm_suspend_noirq(PMSG_FREEZE);
sysdev_suspend(PMSG_FREEZE);
cancelled = suspend_hypercall()
sysdev_resume();
dpm_resume_noirq(cancelled ? PMSG_THAW : PMSG_RESTORE);
dpm_resume_end(cancelled ? PMSG_THAW : PMSG_RESTORE);
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
---
drivers/xen/manage.c | 16 ++++++++--------
drivers/xen/xenbus/xenbus_probe_frontend.c | 8 +++++---
2 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index ebb2928..e9903f1 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -61,7 +61,7 @@ static void xen_post_suspend(int cancelled)
xen_mm_unpin_all();
}
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_XEN_SAVE_RESTORE
static int xen_suspend(void *data)
{
struct suspend_info *si = data;
@@ -69,7 +69,7 @@ static int xen_suspend(void *data)
BUG_ON(!irqs_disabled());
- err = sysdev_suspend(PMSG_SUSPEND);
+ err = sysdev_suspend(PMSG_FREEZE);
if (err) {
printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n",
err);
@@ -118,7 +118,7 @@ static void do_suspend(void)
}
#endif
- err = dpm_suspend_start(PMSG_SUSPEND);
+ err = dpm_suspend_start(PMSG_FREEZE);
if (err) {
printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err);
goto out_thaw;
@@ -127,7 +127,7 @@ static void do_suspend(void)
printk(KERN_DEBUG "suspending xenstore...\n");
xs_suspend();
- err = dpm_suspend_noirq(PMSG_SUSPEND);
+ err = dpm_suspend_noirq(PMSG_FREEZE);
if (err) {
printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);
goto out_resume;
@@ -147,7 +147,7 @@ static void do_suspend(void)
err = stop_machine(xen_suspend, &si, cpumask_of(0));
- dpm_resume_noirq(PMSG_RESUME);
+ dpm_resume_noirq(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
if (err) {
printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
@@ -161,7 +161,7 @@ out_resume:
} else
xs_suspend_cancel();
- dpm_resume_end(PMSG_RESUME);
+ dpm_resume_end(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
/* Make sure timer events get retriggered on all CPUs */
clock_was_set();
@@ -173,7 +173,7 @@ out:
#endif
shutting_down = SHUTDOWN_INVALID;
}
-#endif /* CONFIG_PM_SLEEP */
+#endif /* CONFIG_XEN_SAVE_RESTORE */
struct shutdown_handler {
const char *command;
@@ -202,7 +202,7 @@ static void shutdown_handler(struct xenbus_watch *watch,
{ "poweroff", do_poweroff },
{ "halt", do_poweroff },
{ "reboot", do_reboot },
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_XEN_SAVE_RESTORE
{ "suspend", do_suspend },
#endif
{NULL, NULL},
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index ea83999..b6a2690 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -86,9 +86,11 @@ static struct device_attribute xenbus_frontend_dev_attrs[] = {
};
static const struct dev_pm_ops xenbus_pm_ops = {
- .suspend = xenbus_dev_suspend,
- .resume = xenbus_dev_resume,
- .thaw = xenbus_dev_cancel,
+ .suspend = xenbus_dev_suspend,
+ .resume = xenbus_dev_resume,
+ .freeze = xenbus_dev_suspend,
+ .thaw = xenbus_dev_cancel,
+ .restore = xenbus_dev_resume,
};
static struct xen_bus_type xenbus_frontend = {
--
1.7.0.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v4 2/5] xen: use freeze/restore/thaw PM events for suspend/resume/chkpt
2011-03-12 5:07 [PATCH v3 2/5] xen: use freeze/restore/thaw PM events for suspend/resume/chkpt Shriram Rajagopalan
@ 2011-03-16 17:19 ` Shriram Rajagopalan
2011-03-16 17:41 ` Ian Campbell
0 siblings, 1 reply; 4+ messages in thread
From: Shriram Rajagopalan @ 2011-03-16 17:19 UTC (permalink / raw)
To: xen-devel; +Cc: rjw, Shriram Rajagopalan, konrad.wilk
Use PM_FREEZE, PM_THAW and PM_RESTORE power events for
suspend/resume/checkpoint functionality, instead of PM_SUSPEND
and PM_RESUME. Use of these pm events fixes the Xen Guest hangup
when taking checkpoints. When a suspend event is cancelled
(while taking checkpoints once/continuously), we use PM_THAW
instead of PM_RESUME. PM_RESTORE is used when suspend is not
cancelled. See Documentation/power/devices.txt and linux/pm.h
for more info about freeze, thaw and restore. The sequence of
pm events in a suspend-resume scenario is shown below.
dpm_suspend_start(PMSG_FREEZE);
dpm_suspend_noirq(PMSG_FREEZE);
sysdev_suspend(PMSG_FREEZE);
cancelled = suspend_hypercall()
sysdev_resume();
dpm_resume_noirq(cancelled ? PMSG_THAW : PMSG_RESTORE);
dpm_resume_end(cancelled ? PMSG_THAW : PMSG_RESTORE);
Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
---
drivers/xen/manage.c | 16 ++++++++--------
drivers/xen/xenbus/xenbus_probe_frontend.c | 8 +++++---
2 files changed, 13 insertions(+), 11 deletions(-)
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index ebb2928..95143dd 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -61,7 +61,7 @@ static void xen_post_suspend(int cancelled)
xen_mm_unpin_all();
}
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_HIBERNATION
static int xen_suspend(void *data)
{
struct suspend_info *si = data;
@@ -69,7 +69,7 @@ static int xen_suspend(void *data)
BUG_ON(!irqs_disabled());
- err = sysdev_suspend(PMSG_SUSPEND);
+ err = sysdev_suspend(PMSG_FREEZE);
if (err) {
printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n",
err);
@@ -118,7 +118,7 @@ static void do_suspend(void)
}
#endif
- err = dpm_suspend_start(PMSG_SUSPEND);
+ err = dpm_suspend_start(PMSG_FREEZE);
if (err) {
printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err);
goto out_thaw;
@@ -127,7 +127,7 @@ static void do_suspend(void)
printk(KERN_DEBUG "suspending xenstore...\n");
xs_suspend();
- err = dpm_suspend_noirq(PMSG_SUSPEND);
+ err = dpm_suspend_noirq(PMSG_FREEZE);
if (err) {
printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);
goto out_resume;
@@ -147,7 +147,7 @@ static void do_suspend(void)
err = stop_machine(xen_suspend, &si, cpumask_of(0));
- dpm_resume_noirq(PMSG_RESUME);
+ dpm_resume_noirq(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
if (err) {
printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
@@ -161,7 +161,7 @@ out_resume:
} else
xs_suspend_cancel();
- dpm_resume_end(PMSG_RESUME);
+ dpm_resume_end(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
/* Make sure timer events get retriggered on all CPUs */
clock_was_set();
@@ -173,7 +173,7 @@ out:
#endif
shutting_down = SHUTDOWN_INVALID;
}
-#endif /* CONFIG_PM_SLEEP */
+#endif /* CONFIG_HIBERNATION */
struct shutdown_handler {
const char *command;
@@ -202,7 +202,7 @@ static void shutdown_handler(struct xenbus_watch *watch,
{ "poweroff", do_poweroff },
{ "halt", do_poweroff },
{ "reboot", do_reboot },
-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_HIBERNATION
{ "suspend", do_suspend },
#endif
{NULL, NULL},
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index ea83999..b6a2690 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -86,9 +86,11 @@ static struct device_attribute xenbus_frontend_dev_attrs[] = {
};
static const struct dev_pm_ops xenbus_pm_ops = {
- .suspend = xenbus_dev_suspend,
- .resume = xenbus_dev_resume,
- .thaw = xenbus_dev_cancel,
+ .suspend = xenbus_dev_suspend,
+ .resume = xenbus_dev_resume,
+ .freeze = xenbus_dev_suspend,
+ .thaw = xenbus_dev_cancel,
+ .restore = xenbus_dev_resume,
};
static struct xen_bus_type xenbus_frontend = {
--
1.7.0.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v4 2/5] xen: use freeze/restore/thaw PM events for suspend/resume/chkpt
2011-03-16 17:19 ` [PATCH v4 " Shriram Rajagopalan
@ 2011-03-16 17:41 ` Ian Campbell
2011-03-17 0:05 ` Shriram Rajagopalan
0 siblings, 1 reply; 4+ messages in thread
From: Ian Campbell @ 2011-03-16 17:41 UTC (permalink / raw)
To: Shriram Rajagopalan
Cc: rjw@sisk.pl, xen-devel@lists.xensource.com,
konrad.wilk@oracle.com
On Wed, 2011-03-16 at 17:19 +0000, Shriram Rajagopalan wrote:
> Use PM_FREEZE, PM_THAW and PM_RESTORE power events for
> suspend/resume/checkpoint functionality, instead of PM_SUSPEND
> and PM_RESUME. Use of these pm events fixes the Xen Guest hangup
> when taking checkpoints. When a suspend event is cancelled
> (while taking checkpoints once/continuously), we use PM_THAW
> instead of PM_RESUME. PM_RESTORE is used when suspend is not
> cancelled. See Documentation/power/devices.txt and linux/pm.h
> for more info about freeze, thaw and restore. The sequence of
> pm events in a suspend-resume scenario is shown below.
>
> dpm_suspend_start(PMSG_FREEZE);
>
> dpm_suspend_noirq(PMSG_FREEZE);
>
> sysdev_suspend(PMSG_FREEZE);
> cancelled = suspend_hypercall()
> sysdev_resume();
>
> dpm_resume_noirq(cancelled ? PMSG_THAW : PMSG_RESTORE);
>
> dpm_resume_end(cancelled ? PMSG_THAW : PMSG_RESTORE);
>
> Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Looks good, thanks Shriram.
Acked-by: Ian Campbell <ian.campbell@citrix.com>
> ---
> drivers/xen/manage.c | 16 ++++++++--------
> drivers/xen/xenbus/xenbus_probe_frontend.c | 8 +++++---
> 2 files changed, 13 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
> index ebb2928..95143dd 100644
> --- a/drivers/xen/manage.c
> +++ b/drivers/xen/manage.c
> @@ -61,7 +61,7 @@ static void xen_post_suspend(int cancelled)
> xen_mm_unpin_all();
> }
>
> -#ifdef CONFIG_PM_SLEEP
> +#ifdef CONFIG_HIBERNATION
> static int xen_suspend(void *data)
> {
> struct suspend_info *si = data;
> @@ -69,7 +69,7 @@ static int xen_suspend(void *data)
>
> BUG_ON(!irqs_disabled());
>
> - err = sysdev_suspend(PMSG_SUSPEND);
> + err = sysdev_suspend(PMSG_FREEZE);
> if (err) {
> printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n",
> err);
> @@ -118,7 +118,7 @@ static void do_suspend(void)
> }
> #endif
>
> - err = dpm_suspend_start(PMSG_SUSPEND);
> + err = dpm_suspend_start(PMSG_FREEZE);
> if (err) {
> printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err);
> goto out_thaw;
> @@ -127,7 +127,7 @@ static void do_suspend(void)
> printk(KERN_DEBUG "suspending xenstore...\n");
> xs_suspend();
>
> - err = dpm_suspend_noirq(PMSG_SUSPEND);
> + err = dpm_suspend_noirq(PMSG_FREEZE);
> if (err) {
> printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);
> goto out_resume;
> @@ -147,7 +147,7 @@ static void do_suspend(void)
>
> err = stop_machine(xen_suspend, &si, cpumask_of(0));
>
> - dpm_resume_noirq(PMSG_RESUME);
> + dpm_resume_noirq(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
>
> if (err) {
> printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
> @@ -161,7 +161,7 @@ out_resume:
> } else
> xs_suspend_cancel();
>
> - dpm_resume_end(PMSG_RESUME);
> + dpm_resume_end(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
>
> /* Make sure timer events get retriggered on all CPUs */
> clock_was_set();
> @@ -173,7 +173,7 @@ out:
> #endif
> shutting_down = SHUTDOWN_INVALID;
> }
> -#endif /* CONFIG_PM_SLEEP */
> +#endif /* CONFIG_HIBERNATION */
>
> struct shutdown_handler {
> const char *command;
> @@ -202,7 +202,7 @@ static void shutdown_handler(struct xenbus_watch *watch,
> { "poweroff", do_poweroff },
> { "halt", do_poweroff },
> { "reboot", do_reboot },
> -#ifdef CONFIG_PM_SLEEP
> +#ifdef CONFIG_HIBERNATION
> { "suspend", do_suspend },
> #endif
> {NULL, NULL},
> diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
> index ea83999..b6a2690 100644
> --- a/drivers/xen/xenbus/xenbus_probe_frontend.c
> +++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
> @@ -86,9 +86,11 @@ static struct device_attribute xenbus_frontend_dev_attrs[] = {
> };
>
> static const struct dev_pm_ops xenbus_pm_ops = {
> - .suspend = xenbus_dev_suspend,
> - .resume = xenbus_dev_resume,
> - .thaw = xenbus_dev_cancel,
> + .suspend = xenbus_dev_suspend,
> + .resume = xenbus_dev_resume,
> + .freeze = xenbus_dev_suspend,
> + .thaw = xenbus_dev_cancel,
> + .restore = xenbus_dev_resume,
> };
>
> static struct xen_bus_type xenbus_frontend = {
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v4 2/5] xen: use freeze/restore/thaw PM events for suspend/resume/chkpt
2011-03-16 17:41 ` Ian Campbell
@ 2011-03-17 0:05 ` Shriram Rajagopalan
0 siblings, 0 replies; 4+ messages in thread
From: Shriram Rajagopalan @ 2011-03-17 0:05 UTC (permalink / raw)
To: Ian Campbell; +Cc: xen-devel@lists.xensource.com, konrad.wilk@oracle.com
On Wed, Mar 16, 2011 at 10:41 AM, Ian Campbell <Ian.Campbell@citrix.com> wrote:
> On Wed, 2011-03-16 at 17:19 +0000, Shriram Rajagopalan wrote:
>> Use PM_FREEZE, PM_THAW and PM_RESTORE power events for
>> suspend/resume/checkpoint functionality, instead of PM_SUSPEND
>> and PM_RESUME. Use of these pm events fixes the Xen Guest hangup
>> when taking checkpoints. When a suspend event is cancelled
>> (while taking checkpoints once/continuously), we use PM_THAW
>> instead of PM_RESUME. PM_RESTORE is used when suspend is not
>> cancelled. See Documentation/power/devices.txt and linux/pm.h
>> for more info about freeze, thaw and restore. The sequence of
>> pm events in a suspend-resume scenario is shown below.
>>
>> dpm_suspend_start(PMSG_FREEZE);
>>
>> dpm_suspend_noirq(PMSG_FREEZE);
>>
>> sysdev_suspend(PMSG_FREEZE);
>> cancelled = suspend_hypercall()
>> sysdev_resume();
>>
>> dpm_resume_noirq(cancelled ? PMSG_THAW : PMSG_RESTORE);
>>
>> dpm_resume_end(cancelled ? PMSG_THAW : PMSG_RESTORE);
>>
>> Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
>
> Looks good, thanks Shriram.
>
> Acked-by: Ian Campbell <ian.campbell@citrix.com>
>
>> ---
>> drivers/xen/manage.c | 16 ++++++++--------
>> drivers/xen/xenbus/xenbus_probe_frontend.c | 8 +++++---
>> 2 files changed, 13 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
>> index ebb2928..95143dd 100644
>> --- a/drivers/xen/manage.c
>> +++ b/drivers/xen/manage.c
>> @@ -61,7 +61,7 @@ static void xen_post_suspend(int cancelled)
>> xen_mm_unpin_all();
>> }
>>
>> -#ifdef CONFIG_PM_SLEEP
>> +#ifdef CONFIG_HIBERNATION
>> static int xen_suspend(void *data)
>> {
>> struct suspend_info *si = data;
>> @@ -69,7 +69,7 @@ static int xen_suspend(void *data)
>>
>> BUG_ON(!irqs_disabled());
>>
>> - err = sysdev_suspend(PMSG_SUSPEND);
>> + err = sysdev_suspend(PMSG_FREEZE);
>> if (err) {
>> printk(KERN_ERR "xen_suspend: sysdev_suspend failed: %d\n",
>> err);
>> @@ -118,7 +118,7 @@ static void do_suspend(void)
>> }
>> #endif
>>
>> - err = dpm_suspend_start(PMSG_SUSPEND);
>> + err = dpm_suspend_start(PMSG_FREEZE);
>> if (err) {
>> printk(KERN_ERR "xen suspend: dpm_suspend_start %d\n", err);
>> goto out_thaw;
>> @@ -127,7 +127,7 @@ static void do_suspend(void)
>> printk(KERN_DEBUG "suspending xenstore...\n");
>> xs_suspend();
>>
>> - err = dpm_suspend_noirq(PMSG_SUSPEND);
>> + err = dpm_suspend_noirq(PMSG_FREEZE);
>> if (err) {
>> printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);
>> goto out_resume;
>> @@ -147,7 +147,7 @@ static void do_suspend(void)
>>
>> err = stop_machine(xen_suspend, &si, cpumask_of(0));
>>
>> - dpm_resume_noirq(PMSG_RESUME);
>> + dpm_resume_noirq(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
>>
>> if (err) {
>> printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
>> @@ -161,7 +161,7 @@ out_resume:
>> } else
>> xs_suspend_cancel();
>>
>> - dpm_resume_end(PMSG_RESUME);
>> + dpm_resume_end(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
>>
>> /* Make sure timer events get retriggered on all CPUs */
>> clock_was_set();
>> @@ -173,7 +173,7 @@ out:
>> #endif
>> shutting_down = SHUTDOWN_INVALID;
>> }
>> -#endif /* CONFIG_PM_SLEEP */
>> +#endif /* CONFIG_HIBERNATION */
>>
>> struct shutdown_handler {
>> const char *command;
>> @@ -202,7 +202,7 @@ static void shutdown_handler(struct xenbus_watch *watch,
>> { "poweroff", do_poweroff },
>> { "halt", do_poweroff },
>> { "reboot", do_reboot },
>> -#ifdef CONFIG_PM_SLEEP
>> +#ifdef CONFIG_HIBERNATION
>> { "suspend", do_suspend },
>> #endif
>> {NULL, NULL},
>> diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
>> index ea83999..b6a2690 100644
>> --- a/drivers/xen/xenbus/xenbus_probe_frontend.c
>> +++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
>> @@ -86,9 +86,11 @@ static struct device_attribute xenbus_frontend_dev_attrs[] = {
>> };
>>
>> static const struct dev_pm_ops xenbus_pm_ops = {
>> - .suspend = xenbus_dev_suspend,
>> - .resume = xenbus_dev_resume,
>> - .thaw = xenbus_dev_cancel,
>> + .suspend = xenbus_dev_suspend,
>> + .resume = xenbus_dev_resume,
>> + .freeze = xenbus_dev_suspend,
>> + .thaw = xenbus_dev_cancel,
>> + .restore = xenbus_dev_resume,
>> };
>>
>> static struct xen_bus_type xenbus_frontend = {
>
>
>
How do I go about getting 1/5 and 2/5 patches into xen/next-2.6.32.x ?
It is in konrad's linux-next now.
shriram
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2011-03-17 0:05 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2011-03-12 5:07 [PATCH v3 2/5] xen: use freeze/restore/thaw PM events for suspend/resume/chkpt Shriram Rajagopalan
2011-03-16 17:19 ` [PATCH v4 " Shriram Rajagopalan
2011-03-16 17:41 ` Ian Campbell
2011-03-17 0:05 ` Shriram Rajagopalan
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