diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq_conservative.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq_conservative.c | 91 |
1 files changed, 42 insertions, 49 deletions
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index 3ca3cf06164..7498f2506ad 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -294,31 +294,40 @@ static struct attribute_group dbs_attr_group = { static void dbs_check_cpu(int cpu) { unsigned int idle_ticks, up_idle_ticks, down_idle_ticks; + unsigned int tmp_idle_ticks, total_idle_ticks; unsigned int freq_step; unsigned int freq_down_sampling_rate; - static int down_skip[NR_CPUS]; - static int requested_freq[NR_CPUS]; - static unsigned short init_flag = 0; - struct cpu_dbs_info_s *this_dbs_info; - struct cpu_dbs_info_s *dbs_info; - + static unsigned short down_skip[NR_CPUS]; + static unsigned int requested_freq[NR_CPUS]; + static unsigned int init_flag = NR_CPUS; + struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cpu_dbs_info, cpu); struct cpufreq_policy *policy; - unsigned int j; - this_dbs_info = &per_cpu(cpu_dbs_info, cpu); if (!this_dbs_info->enable) return; - policy = this_dbs_info->cur_policy; - - if ( init_flag == 0 ) { - for_each_online_cpu(j) { - dbs_info = &per_cpu(cpu_dbs_info, j); - requested_freq[j] = dbs_info->cur_policy->cur; + if ( init_flag != 0 ) { + for_each_cpu(init_flag) { + down_skip[init_flag] = 0; + /* I doubt a CPU exists with a freq of 0hz :) */ + requested_freq[init_flag] = 0; } - init_flag = 1; + init_flag = 0; } + /* + * If its a freshly initialised cpu we setup requested_freq. This + * check could be avoided if we did not care about a first time + * stunted increase in CPU speed when there is a load. I feel we + * should be initialising this to something. The removal of a CPU + * is not a problem, after a short time the CPU should settle down + * to a 'natural' frequency. + */ + if (requested_freq[cpu] == 0) + requested_freq[cpu] = this_dbs_info->cur_policy->cur; + + policy = this_dbs_info->cur_policy; + /* * The default safe range is 20% to 80% * Every sampling_rate, we check @@ -335,20 +344,15 @@ static void dbs_check_cpu(int cpu) /* Check for frequency increase */ idle_ticks = UINT_MAX; - for_each_cpu_mask(j, policy->cpus) { - unsigned int tmp_idle_ticks, total_idle_ticks; - struct cpu_dbs_info_s *j_dbs_info; - j_dbs_info = &per_cpu(cpu_dbs_info, j); - /* Check for frequency increase */ - total_idle_ticks = get_cpu_idle_time(j); - tmp_idle_ticks = total_idle_ticks - - j_dbs_info->prev_cpu_idle_up; - j_dbs_info->prev_cpu_idle_up = total_idle_ticks; - - if (tmp_idle_ticks < idle_ticks) - idle_ticks = tmp_idle_ticks; - } + /* Check for frequency increase */ + total_idle_ticks = get_cpu_idle_time(cpu); + tmp_idle_ticks = total_idle_ticks - + this_dbs_info->prev_cpu_idle_up; + this_dbs_info->prev_cpu_idle_up = total_idle_ticks; + + if (tmp_idle_ticks < idle_ticks) + idle_ticks = tmp_idle_ticks; /* Scale idle ticks by 100 and compare with up and down ticks */ idle_ticks *= 100; @@ -357,13 +361,9 @@ static void dbs_check_cpu(int cpu) if (idle_ticks < up_idle_ticks) { down_skip[cpu] = 0; - for_each_cpu_mask(j, policy->cpus) { - struct cpu_dbs_info_s *j_dbs_info; + this_dbs_info->prev_cpu_idle_down = + this_dbs_info->prev_cpu_idle_up; - j_dbs_info = &per_cpu(cpu_dbs_info, j); - j_dbs_info->prev_cpu_idle_down = - j_dbs_info->prev_cpu_idle_up; - } /* if we are already at full speed then break out early */ if (requested_freq[cpu] == policy->max) return; @@ -388,21 +388,14 @@ static void dbs_check_cpu(int cpu) if (down_skip[cpu] < dbs_tuners_ins.sampling_down_factor) return; - idle_ticks = UINT_MAX; - for_each_cpu_mask(j, policy->cpus) { - unsigned int tmp_idle_ticks, total_idle_ticks; - struct cpu_dbs_info_s *j_dbs_info; + /* Check for frequency decrease */ + total_idle_ticks = this_dbs_info->prev_cpu_idle_up; + tmp_idle_ticks = total_idle_ticks - + this_dbs_info->prev_cpu_idle_down; + this_dbs_info->prev_cpu_idle_down = total_idle_ticks; - j_dbs_info = &per_cpu(cpu_dbs_info, j); - /* Check for frequency decrease */ - total_idle_ticks = j_dbs_info->prev_cpu_idle_up; - tmp_idle_ticks = total_idle_ticks - - j_dbs_info->prev_cpu_idle_down; - j_dbs_info->prev_cpu_idle_down = total_idle_ticks; - - if (tmp_idle_ticks < idle_ticks) - idle_ticks = tmp_idle_ticks; - } + if (tmp_idle_ticks < idle_ticks) + idle_ticks = tmp_idle_ticks; /* Scale idle ticks by 100 and compare with up and down ticks */ idle_ticks *= 100; @@ -491,7 +484,7 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy, j_dbs_info = &per_cpu(cpu_dbs_info, j); j_dbs_info->cur_policy = policy; - j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(j); + j_dbs_info->prev_cpu_idle_up = get_cpu_idle_time(cpu); j_dbs_info->prev_cpu_idle_down = j_dbs_info->prev_cpu_idle_up; } |