2014-04-10 22:01:58

by Stratos Karafotis

[permalink] [raw]
Subject: [RFC PATCH] cpufreq: Introduce macros for cpufreq_frequency_table iteration

This patch intoduces 2 macros which can be used for iteration
over cpufreq_frequency_table:

- cpufreq_for_each_entry: iterate over each entry of the table
- cpufreq_for_each_valid_entry: iterate over each entry of the
table that contains a valid frequency.

It should have no functional changes.

Signed-off-by: Stratos Karafotis <[email protected]>
---

I found about 20 occurrences in various drivers that these macros
can be used. I will proceed with the necessary changes if you
approve something like this.

Thanks in advance for your time,
Stratos Karafotis.
---

drivers/cpufreq/freq_table.c | 54 ++++++++++++++++++++------------------------
include/linux/cpufreq.h | 29 ++++++++++++++++++++++++
2 files changed, 53 insertions(+), 30 deletions(-)

diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index 08e7bbc..19bf0c4 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -21,22 +21,18 @@
int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table)
{
+ struct cpufreq_frequency_table *pos;
unsigned int min_freq = ~0;
unsigned int max_freq = 0;
- unsigned int i;

- for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
- unsigned int freq = table[i].frequency;
- if (freq == CPUFREQ_ENTRY_INVALID) {
- pr_debug("table entry %u is invalid, skipping\n", i);
+ cpufreq_for_each_valid_entry(pos, table) {
+ unsigned int freq = pos->frequency;

- continue;
- }
if (!cpufreq_boost_enabled()
- && (table[i].flags & CPUFREQ_BOOST_FREQ))
+ && (pos->flags & CPUFREQ_BOOST_FREQ))
continue;

- pr_debug("table entry %u: %u kHz\n", i, freq);
+ pr_debug("table entry %lu: %u kHz\n", pos - table, freq);
if (freq < min_freq)
min_freq = freq;
if (freq > max_freq)
@@ -57,7 +53,8 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table)
{
- unsigned int next_larger = ~0, freq, i = 0;
+ struct cpufreq_frequency_table *pos;
+ unsigned int next_larger = ~0, freq;
bool found = false;

pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
@@ -65,9 +62,9 @@ int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,

cpufreq_verify_within_cpu_limits(policy);

- for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
- if (freq == CPUFREQ_ENTRY_INVALID)
- continue;
+ cpufreq_for_each_valid_entry(pos, table) {
+ freq = pos->frequency;
+
if ((freq >= policy->min) && (freq <= policy->max)) {
found = true;
break;
@@ -118,7 +115,8 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
.driver_data = ~0,
.frequency = 0,
};
- unsigned int i;
+ struct cpufreq_frequency_table *pos;
+ unsigned int i = 0;

pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
target_freq, relation, policy->cpu);
@@ -132,10 +130,10 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
break;
}

- for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
- unsigned int freq = table[i].frequency;
- if (freq == CPUFREQ_ENTRY_INVALID)
- continue;
+ cpufreq_for_each_valid_entry(pos, table) {
+ unsigned int freq = pos->frequency;
+
+ i = pos - table;
if ((freq < policy->min) || (freq > policy->max))
continue;
switch (relation) {
@@ -184,8 +182,7 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
unsigned int freq)
{
- struct cpufreq_frequency_table *table;
- int i;
+ struct cpufreq_frequency_table *pos, *table;

table = cpufreq_frequency_get_table(policy->cpu);
if (unlikely(!table)) {
@@ -193,9 +190,9 @@ int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
return -ENOENT;
}

- for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
- if (table[i].frequency == freq)
- return i;
+ cpufreq_for_each_entry(pos, table) {
+ if (pos->frequency == freq)
+ return pos - table;
}

return -EINVAL;
@@ -208,16 +205,13 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
bool show_boost)
{
- unsigned int i = 0;
ssize_t count = 0;
- struct cpufreq_frequency_table *table = policy->freq_table;
+ struct cpufreq_frequency_table *pos, *table = policy->freq_table;

if (!table)
return -ENODEV;

- for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
- if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
- continue;
+ cpufreq_for_each_valid_entry(pos, table) {
/*
* show_boost = true and driver_data = BOOST freq
* display BOOST freqs
@@ -229,10 +223,10 @@ static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
* show_boost = false and driver_data != BOOST freq
* display NON BOOST freqs
*/
- if (show_boost ^ (table[i].flags & CPUFREQ_BOOST_FREQ))
+ if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
continue;

- count += sprintf(&buf[count], "%d ", table[i].frequency);
+ count += sprintf(&buf[count], "%d ", pos->frequency);
}
count += sprintf(&buf[count], "\n");

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 5ae5100..1c221c8 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -468,6 +468,35 @@ struct cpufreq_frequency_table {
* order */
};

+static inline bool validate_entry(struct cpufreq_frequency_table *pos)
+{
+ while (pos->frequency != CPUFREQ_TABLE_END)
+ if (pos->frequency == CPUFREQ_ENTRY_INVALID)
+ pos++;
+ else
+ return true;
+ return false;
+}
+
+/*
+ * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table
+ * @pos: the cpufreq_frequency_table * to use as a loop cursor.
+ * @table: the cpufreq_frequency_table * to iterate over.
+ */
+
+#define cpufreq_for_each_entry(pos, table) \
+ for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)
+
+/*
+ * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table
+ * exluding CPUFREQ_ENTRY_INVALID frequencies.
+ * @pos: the cpufreq_frequency_table * to use as a loop cursor.
+ * @table: the cpufreq_frequency_table * to iterate over.
+ */
+
+#define cpufreq_for_each_valid_entry(pos, table) \
+ for (pos = table; validate_entry(pos); pos++)
+
int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table);

--
1.9.0


2014-04-11 04:24:23

by Viresh Kumar

[permalink] [raw]
Subject: Re: [RFC PATCH] cpufreq: Introduce macros for cpufreq_frequency_table iteration

On 11 April 2014 03:31, Stratos Karafotis <[email protected]> wrote:
> This patch intoduces 2 macros which can be used for iteration
> over cpufreq_frequency_table:
>
> - cpufreq_for_each_entry: iterate over each entry of the table
> - cpufreq_for_each_valid_entry: iterate over each entry of the
> table that contains a valid frequency.
>
> It should have no functional changes.
>
> Signed-off-by: Stratos Karafotis <[email protected]>
> ---
>
> I found about 20 occurrences in various drivers that these macros
> can be used. I will proceed with the necessary changes if you
> approve something like this.
>
> Thanks in advance for your time,

Thanks for your time and I find it useful enough. So its a yes from
me :)

But, have you tested this yet?

> Stratos Karafotis.
> ---
>
> drivers/cpufreq/freq_table.c | 54 ++++++++++++++++++++------------------------
> include/linux/cpufreq.h | 29 ++++++++++++++++++++++++
> 2 files changed, 53 insertions(+), 30 deletions(-)
>
> diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
> index 08e7bbc..19bf0c4 100644
> --- a/drivers/cpufreq/freq_table.c
> +++ b/drivers/cpufreq/freq_table.c
> @@ -21,22 +21,18 @@
> int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
> struct cpufreq_frequency_table *table)
> {
> + struct cpufreq_frequency_table *pos;
> unsigned int min_freq = ~0;
> unsigned int max_freq = 0;
> - unsigned int i;
>
> - for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
> - unsigned int freq = table[i].frequency;
> - if (freq == CPUFREQ_ENTRY_INVALID) {
> - pr_debug("table entry %u is invalid, skipping\n", i);
> + cpufreq_for_each_valid_entry(pos, table) {
> + unsigned int freq = pos->frequency;

move the definition part to the top of this routine, we don't need
to create freq for every iteration here. It was bad earlier as well :)

>
> - continue;
> - }
> if (!cpufreq_boost_enabled()
> - && (table[i].flags & CPUFREQ_BOOST_FREQ))
> + && (pos->flags & CPUFREQ_BOOST_FREQ))
> continue;
>
> - pr_debug("table entry %u: %u kHz\n", i, freq);
> + pr_debug("table entry %lu: %u kHz\n", pos - table, freq);
> if (freq < min_freq)
> min_freq = freq;
> if (freq > max_freq)
> @@ -57,7 +53,8 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
> int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
> struct cpufreq_frequency_table *table)
> {
> - unsigned int next_larger = ~0, freq, i = 0;
> + struct cpufreq_frequency_table *pos;
> + unsigned int next_larger = ~0, freq;
> bool found = false;
>
> pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
> @@ -65,9 +62,9 @@ int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
>
> cpufreq_verify_within_cpu_limits(policy);
>
> - for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
> - if (freq == CPUFREQ_ENTRY_INVALID)
> - continue;
> + cpufreq_for_each_valid_entry(pos, table) {
> + freq = pos->frequency;
> +
> if ((freq >= policy->min) && (freq <= policy->max)) {
> found = true;
> break;
> @@ -118,7 +115,8 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
> .driver_data = ~0,
> .frequency = 0,
> };
> - unsigned int i;
> + struct cpufreq_frequency_table *pos;
> + unsigned int i = 0;
>
> pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
> target_freq, relation, policy->cpu);
> @@ -132,10 +130,10 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
> break;
> }
>
> - for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
> - unsigned int freq = table[i].frequency;
> - if (freq == CPUFREQ_ENTRY_INVALID)
> - continue;
> + cpufreq_for_each_valid_entry(pos, table) {
> + unsigned int freq = pos->frequency;

same here.

> +
> + i = pos - table;
> if ((freq < policy->min) || (freq > policy->max))
> continue;
> switch (relation) {
> @@ -184,8 +182,7 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
> int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
> unsigned int freq)
> {
> - struct cpufreq_frequency_table *table;
> - int i;
> + struct cpufreq_frequency_table *pos, *table;
>
> table = cpufreq_frequency_get_table(policy->cpu);
> if (unlikely(!table)) {
> @@ -193,9 +190,9 @@ int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
> return -ENOENT;
> }
>
> - for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
> - if (table[i].frequency == freq)
> - return i;
> + cpufreq_for_each_entry(pos, table) {

use cpufreq_for_each_valid_entry() here as well.

> + if (pos->frequency == freq)
> + return pos - table;
> }
>
> return -EINVAL;
> @@ -208,16 +205,13 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
> static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
> bool show_boost)
> {
> - unsigned int i = 0;
> ssize_t count = 0;
> - struct cpufreq_frequency_table *table = policy->freq_table;
> + struct cpufreq_frequency_table *pos, *table = policy->freq_table;
>
> if (!table)
> return -ENODEV;
>
> - for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
> - if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
> - continue;
> + cpufreq_for_each_valid_entry(pos, table) {
> /*
> * show_boost = true and driver_data = BOOST freq
> * display BOOST freqs
> @@ -229,10 +223,10 @@ static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
> * show_boost = false and driver_data != BOOST freq
> * display NON BOOST freqs
> */
> - if (show_boost ^ (table[i].flags & CPUFREQ_BOOST_FREQ))
> + if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
> continue;
>
> - count += sprintf(&buf[count], "%d ", table[i].frequency);
> + count += sprintf(&buf[count], "%d ", pos->frequency);
> }
> count += sprintf(&buf[count], "\n");
>
> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
> index 5ae5100..1c221c8 100644
> --- a/include/linux/cpufreq.h
> +++ b/include/linux/cpufreq.h
> @@ -468,6 +468,35 @@ struct cpufreq_frequency_table {
> * order */
> };
>
> +static inline bool validate_entry(struct cpufreq_frequency_table *pos)
> +{
> + while (pos->frequency != CPUFREQ_TABLE_END)
> + if (pos->frequency == CPUFREQ_ENTRY_INVALID)
> + pos++;

This is why I asked you if you have tested it or not.

pos is a local variable here and so pos++ wouldn't reflect in the parent
function. But your code will still work as we will check again for the next
INVALID frequency.

Another important thing: This routine is going to be used from a Macro
and so making it inline is very *inefficient*. We are going to use it from
Atleast 20-25 places (as you mentioned) and we definitely aren't looking
to have so many copies of this one :)

So, you should move this to cpufreq.c

> + else
> + return true;
> + return false;
> +}
> +
> +/*
> + * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table
> + * @pos: the cpufreq_frequency_table * to use as a loop cursor.
> + * @table: the cpufreq_frequency_table * to iterate over.
> + */
> +
> +#define cpufreq_for_each_entry(pos, table) \
> + for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)
> +
> +/*
> + * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table
> + * exluding CPUFREQ_ENTRY_INVALID frequencies.
> + * @pos: the cpufreq_frequency_table * to use as a loop cursor.
> + * @table: the cpufreq_frequency_table * to iterate over.
> + */
> +
> +#define cpufreq_for_each_valid_entry(pos, table) \
> + for (pos = table; validate_entry(pos); pos++)
> +
> int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
> struct cpufreq_frequency_table *table);

Otherwise looks fine. Please update all drivers as well :)

2014-04-11 16:31:47

by Stratos Karafotis

[permalink] [raw]
Subject: Re: [RFC PATCH] cpufreq: Introduce macros for cpufreq_frequency_table iteration

On 11/04/2014 07:24 πμ, Viresh Kumar wrote:
> On 11 April 2014 03:31, Stratos Karafotis <[email protected]> wrote:
>> This patch intoduces 2 macros which can be used for iteration
>> over cpufreq_frequency_table:
>>
>> - cpufreq_for_each_entry: iterate over each entry of the table
>> - cpufreq_for_each_valid_entry: iterate over each entry of the
>> table that contains a valid frequency.
>>
>> It should have no functional changes.
>>
>> Signed-off-by: Stratos Karafotis <[email protected]>
>> ---
>>
>> I found about 20 occurrences in various drivers that these macros
>> can be used. I will proceed with the necessary changes if you
>> approve something like this.
>>
>> Thanks in advance for your time,
>
> Thanks for your time and I find it useful enough. So its a yes from
> me :)
>
> But, have you tested this yet?
>
>> Stratos Karafotis.
>> ---
>>
>> drivers/cpufreq/freq_table.c | 54 ++++++++++++++++++++------------------------
>> include/linux/cpufreq.h | 29 ++++++++++++++++++++++++
>> 2 files changed, 53 insertions(+), 30 deletions(-)
>>
>> diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
>> index 08e7bbc..19bf0c4 100644
>> --- a/drivers/cpufreq/freq_table.c
>> +++ b/drivers/cpufreq/freq_table.c
>> @@ -21,22 +21,18 @@
>> int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
>> struct cpufreq_frequency_table *table)
>> {
>> + struct cpufreq_frequency_table *pos;
>> unsigned int min_freq = ~0;
>> unsigned int max_freq = 0;
>> - unsigned int i;
>>
>> - for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
>> - unsigned int freq = table[i].frequency;
>> - if (freq == CPUFREQ_ENTRY_INVALID) {
>> - pr_debug("table entry %u is invalid, skipping\n", i);
>> + cpufreq_for_each_valid_entry(pos, table) {
>> + unsigned int freq = pos->frequency;
>
> move the definition part to the top of this routine, we don't need
> to create freq for every iteration here. It was bad earlier as well :)
>
>>
>> - continue;
>> - }
>> if (!cpufreq_boost_enabled()
>> - && (table[i].flags & CPUFREQ_BOOST_FREQ))
>> + && (pos->flags & CPUFREQ_BOOST_FREQ))
>> continue;
>>
>> - pr_debug("table entry %u: %u kHz\n", i, freq);
>> + pr_debug("table entry %lu: %u kHz\n", pos - table, freq);
>> if (freq < min_freq)
>> min_freq = freq;
>> if (freq > max_freq)
>> @@ -57,7 +53,8 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
>> int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
>> struct cpufreq_frequency_table *table)
>> {
>> - unsigned int next_larger = ~0, freq, i = 0;
>> + struct cpufreq_frequency_table *pos;
>> + unsigned int next_larger = ~0, freq;
>> bool found = false;
>>
>> pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
>> @@ -65,9 +62,9 @@ int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
>>
>> cpufreq_verify_within_cpu_limits(policy);
>>
>> - for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
>> - if (freq == CPUFREQ_ENTRY_INVALID)
>> - continue;
>> + cpufreq_for_each_valid_entry(pos, table) {
>> + freq = pos->frequency;
>> +
>> if ((freq >= policy->min) && (freq <= policy->max)) {
>> found = true;
>> break;
>> @@ -118,7 +115,8 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
>> .driver_data = ~0,
>> .frequency = 0,
>> };
>> - unsigned int i;
>> + struct cpufreq_frequency_table *pos;
>> + unsigned int i = 0;
>>
>> pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
>> target_freq, relation, policy->cpu);
>> @@ -132,10 +130,10 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
>> break;
>> }
>>
>> - for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
>> - unsigned int freq = table[i].frequency;
>> - if (freq == CPUFREQ_ENTRY_INVALID)
>> - continue;
>> + cpufreq_for_each_valid_entry(pos, table) {
>> + unsigned int freq = pos->frequency;
>
> same here.
>
>> +
>> + i = pos - table;
>> if ((freq < policy->min) || (freq > policy->max))
>> continue;
>> switch (relation) {
>> @@ -184,8 +182,7 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
>> int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
>> unsigned int freq)
>> {
>> - struct cpufreq_frequency_table *table;
>> - int i;
>> + struct cpufreq_frequency_table *pos, *table;
>>
>> table = cpufreq_frequency_get_table(policy->cpu);
>> if (unlikely(!table)) {
>> @@ -193,9 +190,9 @@ int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
>> return -ENOENT;
>> }
>>
>> - for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
>> - if (table[i].frequency == freq)
>> - return i;
>> + cpufreq_for_each_entry(pos, table) {
>
> use cpufreq_for_each_valid_entry() here as well.
>
>> + if (pos->frequency == freq)
>> + return pos - table;
>> }
>>
>> return -EINVAL;
>> @@ -208,16 +205,13 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
>> static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
>> bool show_boost)
>> {
>> - unsigned int i = 0;
>> ssize_t count = 0;
>> - struct cpufreq_frequency_table *table = policy->freq_table;
>> + struct cpufreq_frequency_table *pos, *table = policy->freq_table;
>>
>> if (!table)
>> return -ENODEV;
>>
>> - for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
>> - if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
>> - continue;
>> + cpufreq_for_each_valid_entry(pos, table) {
>> /*
>> * show_boost = true and driver_data = BOOST freq
>> * display BOOST freqs
>> @@ -229,10 +223,10 @@ static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
>> * show_boost = false and driver_data != BOOST freq
>> * display NON BOOST freqs
>> */
>> - if (show_boost ^ (table[i].flags & CPUFREQ_BOOST_FREQ))
>> + if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
>> continue;
>>
>> - count += sprintf(&buf[count], "%d ", table[i].frequency);
>> + count += sprintf(&buf[count], "%d ", pos->frequency);
>> }
>> count += sprintf(&buf[count], "\n");
>>
>> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
>> index 5ae5100..1c221c8 100644
>> --- a/include/linux/cpufreq.h
>> +++ b/include/linux/cpufreq.h
>> @@ -468,6 +468,35 @@ struct cpufreq_frequency_table {
>> * order */
>> };
>>
>> +static inline bool validate_entry(struct cpufreq_frequency_table *pos)
>> +{
>> + while (pos->frequency != CPUFREQ_TABLE_END)
>> + if (pos->frequency == CPUFREQ_ENTRY_INVALID)
>> + pos++;
>
> This is why I asked you if you have tested it or not.
> pos is a local variable here and so pos++ wouldn't reflect in the parent
> function. But your code will still work as we will check again for the next
> INVALID frequency.

Of course, you are right!
Yes, I partially tested it. But my frequency table didn't contain an
invalid entry. I will fix it.

> Another important thing: This routine is going to be used from a Macro
> and so making it inline is very *inefficient*. We are going to use it from
> Atleast 20-25 places (as you mentioned) and we definitely aren't looking
> to have so many copies of this one :)
>
> So, you should move this to cpufreq.c

OK, I will do it. I was thinking about performance but as you mentioned
20 copies are too much. :)

>> + else
>> + return true;
>> + return false;
>> +}
>> +
>> +/*
>> + * cpufreq_for_each_entry - iterate over a cpufreq_frequency_table
>> + * @pos: the cpufreq_frequency_table * to use as a loop cursor.
>> + * @table: the cpufreq_frequency_table * to iterate over.
>> + */
>> +
>> +#define cpufreq_for_each_entry(pos, table) \
>> + for (pos = table; pos->frequency != CPUFREQ_TABLE_END; pos++)
>> +
>> +/*
>> + * cpufreq_for_each_valid_entry - iterate over a cpufreq_frequency_table
>> + * exluding CPUFREQ_ENTRY_INVALID frequencies.
>> + * @pos: the cpufreq_frequency_table * to use as a loop cursor.
>> + * @table: the cpufreq_frequency_table * to iterate over.
>> + */
>> +
>> +#define cpufreq_for_each_valid_entry(pos, table) \
>> + for (pos = table; validate_entry(pos); pos++)
>> +
>> int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
>> struct cpufreq_frequency_table *table);
>
> Otherwise looks fine. Please update all drivers as well :)
>

I will prepare the patches with your suggestions.
Thank you very much for your review!


Stratos