lkml.org 
[lkml]   [2018]   [May]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.9 236/329] cpufreq: CPPC: Initialize shared perf capabilities of CPUs
Date
4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Shunyong Yang <shunyong.yang@hxt-semitech.com>

[ Upstream commit 8913315e9459b146e5888ab5138e10daa061b885 ]

When multiple CPUs are related in one cpufreq policy, the first online
CPU will be chosen by default to handle cpufreq operations. Let's take
cpu0 and cpu1 as an example.

When cpu0 is offline, policy->cpu will be shifted to cpu1. cpu1's perf
capabilities should be initialized. Otherwise, perf capabilities are 0s
and speed change can not take effect.

This patch copies perf capabilities of the first online CPU to other
shared CPUs when policy shared type is CPUFREQ_SHARED_TYPE_ANY.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Shunyong Yang <shunyong.yang@hxt-semitech.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/cpufreq/cppc_cpufreq.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -151,9 +151,19 @@ static int cppc_cpufreq_cpu_init(struct
policy->cpuinfo.transition_latency = cppc_get_transition_latency(cpu_num);
policy->shared_type = cpu->shared_type;

- if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY)
+ if (policy->shared_type == CPUFREQ_SHARED_TYPE_ANY) {
+ int i;
+
cpumask_copy(policy->cpus, cpu->shared_cpu_map);
- else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) {
+
+ for_each_cpu(i, policy->cpus) {
+ if (unlikely(i == policy->cpu))
+ continue;
+
+ memcpy(&all_cpu_data[i]->perf_caps, &cpu->perf_caps,
+ sizeof(cpu->perf_caps));
+ }
+ } else if (policy->shared_type == CPUFREQ_SHARED_TYPE_ALL) {
/* Support only SW_ANY for now. */
pr_debug("Unsupported CPU co-ord type\n");
return -EFAULT;

\
 
 \ /
  Last update: 2018-05-28 16:15    [W:0.613 / U:0.044 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site