diff options
| author |   Xiaoguang Chen <chenxg@marvell.com> | 2013-11-07 10:28:50 +0800 |
|---|---|---|
| committer |   Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-11-07 19:36:19 +0100 |
| commit | 3baa976ae644f76f5cdb5be0fb26754c3bfb32cb (patch) | |
| tree | 5c571eb6bfb164a128c18050f310189275061159 /drivers/cpufreq/cpufreq_conservative.c | |
| parent | intel_pstate: skip the driver if ACPI has power mgmt option (diff) | |
| download | linux-dev-3baa976ae644f76f5cdb5be0fb26754c3bfb32cb.tar.xz linux-dev-3baa976ae644f76f5cdb5be0fb26754c3bfb32cb.zip | |
cpufreq: conservative: fix requested_freq reduction issue
When decreasing frequency, requested_freq may be less than
freq_target, So requested_freq minus freq_target may be negative,
But reqested_freq's unit is unsigned int, then the negative result
will be one larger interger which may be even higher than
requested_freq.
This patch is to fix such issue. when result becomes negative,
set requested_freq as the min value of policy.
Signed-off-by: Xiaoguang Chen <chenxg@marvell.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq/cpufreq_conservative.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq_conservative.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index f62d822048e6..218460fcd2e4 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -80,13 +80,18 @@ static void cs_check_cpu(int cpu, unsigned int load) /* Check for frequency decrease */ if (load < cs_tuners->down_threshold) { + unsigned int freq_target; /* * if we cannot reduce the frequency anymore, break out early */ if (policy->cur == policy->min) return; - dbs_info->requested_freq -= get_freq_target(cs_tuners, policy); + freq_target = get_freq_target(cs_tuners, policy); + if (dbs_info->requested_freq > freq_target) + dbs_info->requested_freq -= freq_target; + else + dbs_info->requested_freq = policy->min; __cpufreq_driver_target(policy, dbs_info->requested_freq, CPUFREQ_RELATION_L); |