* [PATCH 5/5] cpufreq: acpi-cpufreq: Clean up hot plug notifier callback.
@ 2016-03-18 21:26 Richard Cochran
2016-03-23 21:26 ` Rafael J. Wysocki
0 siblings, 1 reply; 2+ messages in thread
From: Richard Cochran @ 2016-03-18 21:26 UTC (permalink / raw)
To: linux-kernel; +Cc: rt, Rafael J. Wysocki, Viresh Kumar, linux-pm
This driver has two issues. First, it tries to fiddle with the hot
plugged CPU's MSR on the UP_PREPARE event, at a time when the CPU is
not yet online. Second, the driver sets the "boost-disable" bit for a
CPU when going down, but does not clear the bit again if the CPU comes
up again due to DOWN_FAILED.
This patch fixes the issues by changing the driver to react to the
ONLINE/DOWN_FAILED events instead of UP_PREPARE. As an added benefit,
the driver also becomes symmetric with respect to the hot plug
mechanism.
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-pm@vger.kernel.org
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
---
drivers/cpufreq/acpi-cpufreq.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 51eef87..7006a43 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -540,8 +540,10 @@ static int boost_notify(struct notifier_block *nb, unsigned long action,
*/
switch (action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
+ case CPU_DOWN_FAILED:
+ case CPU_DOWN_FAILED_FROZEN:
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
break;
--
2.1.4
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH 5/5] cpufreq: acpi-cpufreq: Clean up hot plug notifier callback.
2016-03-18 21:26 [PATCH 5/5] cpufreq: acpi-cpufreq: Clean up hot plug notifier callback Richard Cochran
@ 2016-03-23 21:26 ` Rafael J. Wysocki
0 siblings, 0 replies; 2+ messages in thread
From: Rafael J. Wysocki @ 2016-03-23 21:26 UTC (permalink / raw)
To: Richard Cochran; +Cc: linux-kernel, rt, Viresh Kumar, linux-pm
On Friday, March 18, 2016 10:26:11 PM Richard Cochran wrote:
> This driver has two issues. First, it tries to fiddle with the hot
> plugged CPU's MSR on the UP_PREPARE event, at a time when the CPU is
> not yet online. Second, the driver sets the "boost-disable" bit for a
> CPU when going down, but does not clear the bit again if the CPU comes
> up again due to DOWN_FAILED.
>
> This patch fixes the issues by changing the driver to react to the
> ONLINE/DOWN_FAILED events instead of UP_PREPARE. As an added benefit,
> the driver also becomes symmetric with respect to the hot plug
> mechanism.
>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Viresh Kumar <viresh.kumar@linaro.org>
> Cc: linux-pm@vger.kernel.org
> Signed-off-by: Richard Cochran <rcochran@linutronix.de>
> ---
> drivers/cpufreq/acpi-cpufreq.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
> index 51eef87..7006a43 100644
> --- a/drivers/cpufreq/acpi-cpufreq.c
> +++ b/drivers/cpufreq/acpi-cpufreq.c
> @@ -540,8 +540,10 @@ static int boost_notify(struct notifier_block *nb, unsigned long action,
> */
>
> switch (action) {
> - case CPU_UP_PREPARE:
> - case CPU_UP_PREPARE_FROZEN:
> + case CPU_DOWN_FAILED:
> + case CPU_DOWN_FAILED_FROZEN:
> + case CPU_ONLINE:
> + case CPU_ONLINE_FROZEN:
> boost_set_msrs(acpi_cpufreq_driver.boost_enabled, cpumask);
> break;
Applied, thanks!
^ permalink raw reply [flat|nested] 2+ messages in thread
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