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Date: Mon, 27 Jun 2016 16:04:07 +0530
From: Viresh Kumar <viresh.kumar@...aro.org>
To: Rafael Wysocki <rjw@...ysocki.net>,
Viresh Kumar <viresh.kumar@...aro.org>
Cc: linaro-kernel@...ts.linaro.org, linux-pm@...r.kernel.org,
linux-kernel@...r.kernel.org, steve.muckle@...aro.org,
francescolavra.fl@...il.com
Subject: [PATCH V6 1/2] cpufreq: Handle sorted frequency tables more efficiently
cpufreq drivers aren't required to provide a sorted frequency table
today, and even the ones which provide a sorted table aren't handled
efficiently by cpufreq core.
This patch adds infrastructure to verify if the freq-table provided by
the drivers is sorted or not, and use efficient helpers if they are
sorted.
Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
Thanks to Francesco for spotting few wrong comments and a statement in
V5. They are fixed now.
drivers/cpufreq/freq_table.c | 73 ++++++++++++--
include/linux/cpufreq.h | 234 ++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 296 insertions(+), 11 deletions(-)
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index eac8bcbdaad1..3bbbf9e6960c 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -113,9 +113,9 @@ int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
}
EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
-int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
- unsigned int target_freq,
- unsigned int relation)
+int cpufreq_table_index_unsorted(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
{
struct cpufreq_frequency_table optimal = {
.driver_data = ~0,
@@ -205,7 +205,7 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
table[index].frequency);
return index;
}
-EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
+EXPORT_SYMBOL_GPL(cpufreq_table_index_unsorted);
int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
unsigned int freq)
@@ -297,15 +297,72 @@ struct freq_attr *cpufreq_generic_attr[] = {
};
EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
+static int set_freq_table_sorted(struct cpufreq_policy *policy)
+{
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;
+ struct cpufreq_frequency_table *prev = NULL;
+ int ascending = 0;
+
+ policy->freq_table_sorted = CPUFREQ_TABLE_UNSORTED;
+
+ cpufreq_for_each_valid_entry(pos, table) {
+ if (!prev) {
+ prev = pos;
+ continue;
+ }
+
+ if (pos->frequency == prev->frequency) {
+ pr_warn("Duplicate freq-table entries: %u\n",
+ pos->frequency);
+ return -EINVAL;
+ }
+
+ /* Frequency increased from prev to pos */
+ if (pos->frequency > prev->frequency) {
+ /* But frequency was decreasing earlier */
+ if (ascending < 0) {
+ pr_debug("Freq table is unsorted\n");
+ return 0;
+ }
+
+ ascending++;
+ } else {
+ /* Frequency decreased from prev to pos */
+
+ /* But frequency was increasing earlier */
+ if (ascending > 0) {
+ pr_debug("Freq table is unsorted\n");
+ return 0;
+ }
+
+ ascending--;
+ }
+
+ prev = pos;
+ }
+
+ if (ascending > 0)
+ policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_ASCENDING;
+ else
+ policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_DESCENDING;
+
+ pr_debug("Freq table is sorted in %s order\n",
+ ascending > 0 ? "ascending" : "descending");
+
+ return 0;
+}
+
int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table)
{
- int ret = cpufreq_frequency_table_cpuinfo(policy, table);
+ int ret;
- if (!ret)
- policy->freq_table = table;
+ ret = cpufreq_frequency_table_cpuinfo(policy, table);
+ if (ret)
+ return ret;
- return ret;
+ policy->freq_table = table;
+ return set_freq_table_sorted(policy);
}
EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index c378776628b4..c6410b1b2490 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -36,6 +36,12 @@
struct cpufreq_governor;
+enum cpufreq_table_sorting {
+ CPUFREQ_TABLE_UNSORTED,
+ CPUFREQ_TABLE_SORTED_ASCENDING,
+ CPUFREQ_TABLE_SORTED_DESCENDING
+};
+
struct cpufreq_freqs {
unsigned int cpu; /* cpu nr */
unsigned int old;
@@ -87,6 +93,7 @@ struct cpufreq_policy {
struct cpufreq_user_policy user_policy;
struct cpufreq_frequency_table *freq_table;
+ enum cpufreq_table_sorting freq_table_sorted;
struct list_head policy_list;
struct kobject kobj;
@@ -597,9 +604,9 @@ int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table);
int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy);
-int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
- unsigned int target_freq,
- unsigned int relation);
+int cpufreq_table_index_unsorted(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation);
int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
unsigned int freq);
@@ -610,6 +617,227 @@ int cpufreq_boost_trigger_state(int state);
int cpufreq_boost_enabled(void);
int cpufreq_enable_boost_support(void);
bool policy_has_boost_freq(struct cpufreq_policy *policy);
+
+/* Find lowest freq at or above target in a table in ascending order */
+static inline int cpufreq_table_find_index_al(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ struct cpufreq_frequency_table *table = policy->freq_table;
+ unsigned int freq;
+ int i, best = -1;
+
+ for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
+ freq = table[i].frequency;
+
+ if (freq >= target_freq)
+ return i;
+
+ best = i;
+ }
+
+ return best;
+}
+
+/* Find lowest freq at or above target in a table in descending order */
+static inline int cpufreq_table_find_index_dl(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ struct cpufreq_frequency_table *table = policy->freq_table;
+ unsigned int freq;
+ int i, best = -1;
+
+ for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
+ freq = table[i].frequency;
+
+ if (freq == target_freq)
+ return i;
+
+ if (freq > target_freq) {
+ best = i;
+ continue;
+ }
+
+ /* No freq found above target_freq */
+ if (best == -1)
+ return i;
+
+ return best;
+ }
+
+ return best;
+}
+
+/* Works only on sorted freq-tables */
+static inline int cpufreq_table_find_index_l(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ target_freq = clamp_val(target_freq, policy->min, policy->max);
+
+ if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING)
+ return cpufreq_table_find_index_al(policy, target_freq);
+ else
+ return cpufreq_table_find_index_dl(policy, target_freq);
+}
+
+/* Find highest freq at or below target in a table in ascending order */
+static inline int cpufreq_table_find_index_ah(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ struct cpufreq_frequency_table *table = policy->freq_table;
+ unsigned int freq;
+ int i, best = -1;
+
+ for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
+ freq = table[i].frequency;
+
+ if (freq == target_freq)
+ return i;
+
+ if (freq < target_freq) {
+ best = i;
+ continue;
+ }
+
+ /* No freq found below target_freq */
+ if (best == -1)
+ return i;
+
+ return best;
+ }
+
+ return best;
+}
+
+/* Find highest freq at or below target in a table in descending order */
+static inline int cpufreq_table_find_index_dh(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ struct cpufreq_frequency_table *table = policy->freq_table;
+ unsigned int freq;
+ int i, best = -1;
+
+ for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
+ freq = table[i].frequency;
+
+ if (freq <= target_freq)
+ return i;
+
+ best = i;
+ }
+
+ return best;
+}
+
+/* Works only on sorted freq-tables */
+static inline int cpufreq_table_find_index_h(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ target_freq = clamp_val(target_freq, policy->min, policy->max);
+
+ if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING)
+ return cpufreq_table_find_index_ah(policy, target_freq);
+ else
+ return cpufreq_table_find_index_dh(policy, target_freq);
+}
+
+/* Find closest freq to target in a table in ascending order */
+static inline int cpufreq_table_find_index_ac(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ struct cpufreq_frequency_table *table = policy->freq_table;
+ unsigned int freq;
+ int i, best = -1;
+
+ for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
+ freq = table[i].frequency;
+
+ if (freq == target_freq)
+ return i;
+
+ if (freq < target_freq) {
+ best = i;
+ continue;
+ }
+
+ /* No freq found below target_freq */
+ if (best == -1)
+ return i;
+
+ /* Choose the closest freq */
+ if (target_freq - table[best].frequency > freq - target_freq)
+ return i;
+
+ return best;
+ }
+
+ return best;
+}
+
+/* Find closest freq to target in a table in descending order */
+static inline int cpufreq_table_find_index_dc(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ struct cpufreq_frequency_table *table = policy->freq_table;
+ unsigned int freq;
+ int i, best = -1;
+
+ for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
+ freq = table[i].frequency;
+
+ if (freq == target_freq)
+ return i;
+
+ if (freq > target_freq) {
+ best = i;
+ continue;
+ }
+
+ /* No freq found above target_freq */
+ if (best == -1)
+ return i;
+
+ /* Choose the closest freq */
+ if (table[best].frequency - target_freq > target_freq - freq)
+ return i;
+
+ return best;
+ }
+
+ return best;
+}
+
+/* Works only on sorted freq-tables */
+static inline int cpufreq_table_find_index_c(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ target_freq = clamp_val(target_freq, policy->min, policy->max);
+
+ if (policy->freq_table_sorted == CPUFREQ_TABLE_SORTED_ASCENDING)
+ return cpufreq_table_find_index_ac(policy, target_freq);
+ else
+ return cpufreq_table_find_index_dc(policy, target_freq);
+}
+
+static inline int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ if (unlikely(policy->freq_table_sorted == CPUFREQ_TABLE_UNSORTED))
+ return cpufreq_table_index_unsorted(policy, target_freq,
+ relation);
+
+ switch (relation) {
+ case CPUFREQ_RELATION_L:
+ return cpufreq_table_find_index_l(policy, target_freq);
+ case CPUFREQ_RELATION_H:
+ return cpufreq_table_find_index_h(policy, target_freq);
+ case CPUFREQ_RELATION_C:
+ return cpufreq_table_find_index_c(policy, target_freq);
+ default:
+ pr_err("%s: Invalid relation: %d\n", __func__, relation);
+ return -EINVAL;
+ }
+}
#else
static inline int cpufreq_boost_trigger_state(int state)
{
--
2.7.4
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