Re: [PATCH v2 1/8] cpufreq: Introduce macros for cpufreq_frequency_table iteration

From: Randy Dunlap
Date: Tue Apr 15 2014 - 19:47:42 EST


On 04/15/2014 03:25 PM, Stratos Karafotis wrote:
> Many cpufreq drivers need to iterate over the cpufreq_frequency_table
> for various tasks.
>
> This patch introduces two macros which can be used for iteration over
> cpufreq_frequency_table keeping a common coding style across drivers:
>
> - cpufreq_for_each_entry: iterate over each entry of the table
> - cpufreq_for_each_valid_entry: iterate over each entry that contains
> a valid frequency.
>
> It should have no functional changes.
>
> Signed-off-by: Stratos Karafotis <stratosk@xxxxxxxxxxxx>
> ---
> Documentation/cpu-freq/cpu-drivers.txt | 16 ++++++++++++++++
> drivers/cpufreq/cpufreq.c | 11 +++++++++++
> include/linux/cpufreq.h | 21 +++++++++++++++++++++
> 3 files changed, 48 insertions(+)
>
> diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt
> index 48da5fd..2c9156a 100644
> --- a/Documentation/cpu-freq/cpu-drivers.txt
> +++ b/Documentation/cpu-freq/cpu-drivers.txt
> @@ -228,3 +228,19 @@ is the corresponding frequency table helper for the ->target
> stage. Just pass the values to this function, and the unsigned int
> index returns the number of the frequency table entry which contains
> the frequency the CPU shall be set to.
> +
> +The following macros can be used as iterators over cpufreq_frequency_table:

<insert blank line>

> +cpufreq_for_each_entry(pos, table) - iterates over all entries of frequency
> +table.

<insert blank line>

> +cpufreq-for_each_valid_entry(pos, table) - iterates over all entries,
> +excluding CPUFREQ_ENTRY_INVALID frequencies.
> +Use arguments "pos" - a cpufreq_frequency_table * as a loop cursor and
> +"table" - the cpufreq_frequency_table * you want to iterate over.

<insert blank line>

> +For example:
> +
> + struct cpufreq_frequency_table *pos, *driver_freq_table;
> +
> + cpufreq_for_each_entry(pos, driver_freq_table) {
> + /* Do something with pos */
> + pos->frequency = ...
> + }

> diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
> index 5ae5100..4f913b5 100644
> --- a/include/linux/cpufreq.h
> +++ b/include/linux/cpufreq.h
> @@ -468,6 +468,27 @@ struct cpufreq_frequency_table {
> * order */
> };
>
> +bool cpufreq_next_valid(struct cpufreq_frequency_table **pos);
> +
> +/*
> + * 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.

excluding

> + * @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; cpufreq_next_valid(&pos); pos++)
> +
> int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
> struct cpufreq_frequency_table *table);
>
>


--
~Randy
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/