On 03/19/2014 08:28 PM, Rafael J. Wysocki wrote:
On Wednesday, March 19, 2014 11:31:31 PM Rafael J. Wysocki wrote:
On Wednesday, March 19, 2014 08:45:53 AM [email protected] wrote:
From: Dirk Brandewie <[email protected]>
This callback allows the driver to do clean up before the CPU is
completely down and its state cannot be modified. This is used
by the intel_pstate driver to reduce the requested P state prior to
the core going away. This is required because the requested P state
of the offline core is used to select the package P state. This
effectively sets the floor package P state to the requested P state on
the offline core.
Signed-off-by: Dirk Brandewie <[email protected]>
To speed up things a bit I changed the name of the new callback to ->stop_cpu
and made it void.
I also modified patch [2/2] accordingly and queued the both of them up for 3.15.
Please check the bleeding-edge branch.
I wouldn't like to need to do anything like that any more in the future, though.
Sorry had appointments yesterday afternoon.
bleeding-edge looks good
---
Documentation/cpu-freq/cpu-drivers.txt | 8 +++++++-
drivers/cpufreq/cpufreq.c | 3 ++-
include/linux/cpufreq.h | 1 +
3 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/Documentation/cpu-freq/cpu-drivers.txt
b/Documentation/cpu-freq/cpu-drivers.txt
index 8b1a445..79def80 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -61,7 +61,13 @@ target_index - See below on the differences.
And optionally
-cpufreq_driver.exit - A pointer to a per-CPU cleanup function.
+cpufreq_driver.exit - A pointer to a per-CPU cleanup
+ function called during CPU_POST_DEAD
+ phase of cpu hotplug process.
+
+cpufreq_driver.stop - A pointer to a per-CPU stop function
+ called during CPU_DOWN_PREPARE phase of
+ cpu hotplug process.
cpufreq_driver.resume - A pointer to a per-CPU resume function
which is called with interrupts disabled
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cf485d9..bb20292 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1336,7 +1336,8 @@ static int __cpufreq_remove_dev_prepare(struct device
*dev,
__func__, new_cpu, cpu);
}
}
- }
+ } else if (cpufreq_driver->stop && cpufreq_driver->setpolicy)
+ cpufreq_driver->stop(policy);
Nit: Why is it an int function if the only caller doesn't check the
return value? It should be void.
return 0;
}
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 4d89e0e..ff8db19 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -224,6 +224,7 @@ struct cpufreq_driver {
int (*bios_limit) (int cpu, unsigned int *limit);
int (*exit) (struct cpufreq_policy *policy);
+ int (*stop) (struct cpufreq_policy *policy);
int (*suspend) (struct cpufreq_policy *policy);
int (*resume) (struct cpufreq_policy *policy);
struct freq_attr **attr;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
