[tip: timers/core] clocksource: Cleanup struct clocksource and documentation

From: tip-bot2 for Thomas Gleixner
Date: Mon Feb 17 2020 - 10:12:06 EST


The following commit has been merged into the timers/core branch of tip:

Commit-ID: 3bd142a46b561a12408e8db78cc6d62eb1c6b84e
Gitweb: https://git.kernel.org/tip/3bd142a46b561a12408e8db78cc6d62eb1c6b84e
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate: Fri, 07 Feb 2020 13:38:53 +01:00
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Mon, 17 Feb 2020 14:40:22 +01:00

clocksource: Cleanup struct clocksource and documentation

Reformat the struct definition, add missing member documentation.
No functional change.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Link: https://lkml.kernel.org/r/20200207124402.825471920@xxxxxxxxxxxxx


---
include/linux/clocksource.h | 87 +++++++++++++++++++-----------------
1 file changed, 47 insertions(+), 40 deletions(-)

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index b21db53..2c4574b 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -32,9 +32,19 @@ struct module;
* Provides mostly state-free accessors to the underlying hardware.
* This is the structure used for system time.
*
- * @name: ptr to clocksource name
- * @list: list head for registration
- * @rating: rating value for selection (higher is better)
+ * @read: Returns a cycle value, passes clocksource as argument
+ * @mask: Bitmask for two's complement
+ * subtraction of non 64 bit counters
+ * @mult: Cycle to nanosecond multiplier
+ * @shift: Cycle to nanosecond divisor (power of two)
+ * @max_idle_ns: Maximum idle time permitted by the clocksource (nsecs)
+ * @maxadj: Maximum adjustment value to mult (~11%)
+ * @archdata: Optional arch-specific data
+ * @max_cycles: Maximum safe cycle value which won't overflow on
+ * multiplication
+ * @name: Pointer to clocksource name
+ * @list: List head for registration (internal)
+ * @rating: Rating value for selection (higher is better)
* To avoid rating inflation the following
* list should give you a guide as to how
* to assign your clocksource a rating
@@ -49,27 +59,23 @@ struct module;
* 400-499: Perfect
* The ideal clocksource. A must-use where
* available.
- * @read: returns a cycle value, passes clocksource as argument
- * @enable: optional function to enable the clocksource
- * @disable: optional function to disable the clocksource
- * @mask: bitmask for two's complement
- * subtraction of non 64 bit counters
- * @mult: cycle to nanosecond multiplier
- * @shift: cycle to nanosecond divisor (power of two)
- * @max_idle_ns: max idle time permitted by the clocksource (nsecs)
- * @maxadj: maximum adjustment value to mult (~11%)
- * @max_cycles: maximum safe cycle value which won't overflow on multiplication
- * @flags: flags describing special properties
- * @archdata: arch-specific data
- * @suspend: suspend function for the clocksource, if necessary
- * @resume: resume function for the clocksource, if necessary
+ * @flags: Flags describing special properties
+ * @enable: Optional function to enable the clocksource
+ * @disable: Optional function to disable the clocksource
+ * @suspend: Optional suspend function for the clocksource
+ * @resume: Optional resume function for the clocksource
* @mark_unstable: Optional function to inform the clocksource driver that
* the watchdog marked the clocksource unstable
- * @owner: module reference, must be set by clocksource in modules
+ * @tick_stable: Optional function called periodically from the watchdog
+ * code to provide stable syncrhonization points
+ * @wd_list: List head to enqueue into the watchdog list (internal)
+ * @cs_last: Last clocksource value for clocksource watchdog
+ * @wd_last: Last watchdog value corresponding to @cs_last
+ * @owner: Module reference, must be set by clocksource in modules
*
* Note: This struct is not used in hotpathes of the timekeeping code
* because the timekeeper caches the hot path fields in its own data
- * structure, so no line cache alignment is required,
+ * structure, so no cache line alignment is required,
*
* The pointer to the clocksource itself is handed to the read
* callback. If you need extra information there you can wrap struct
@@ -78,35 +84,36 @@ struct module;
* structure.
*/
struct clocksource {
- u64 (*read)(struct clocksource *cs);
- u64 mask;
- u32 mult;
- u32 shift;
- u64 max_idle_ns;
- u32 maxadj;
+ u64 (*read)(struct clocksource *cs);
+ u64 mask;
+ u32 mult;
+ u32 shift;
+ u64 max_idle_ns;
+ u32 maxadj;
#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
struct arch_clocksource_data archdata;
#endif
- u64 max_cycles;
- const char *name;
- struct list_head list;
- int rating;
- int (*enable)(struct clocksource *cs);
- void (*disable)(struct clocksource *cs);
- unsigned long flags;
- void (*suspend)(struct clocksource *cs);
- void (*resume)(struct clocksource *cs);
- void (*mark_unstable)(struct clocksource *cs);
- void (*tick_stable)(struct clocksource *cs);
+ u64 max_cycles;
+ const char *name;
+ struct list_head list;
+ int rating;
+ unsigned long flags;
+
+ int (*enable)(struct clocksource *cs);
+ void (*disable)(struct clocksource *cs);
+ void (*suspend)(struct clocksource *cs);
+ void (*resume)(struct clocksource *cs);
+ void (*mark_unstable)(struct clocksource *cs);
+ void (*tick_stable)(struct clocksource *cs);

/* private: */
#ifdef CONFIG_CLOCKSOURCE_WATCHDOG
/* Watchdog related data, used by the framework */
- struct list_head wd_list;
- u64 cs_last;
- u64 wd_last;
+ struct list_head wd_list;
+ u64 cs_last;
+ u64 wd_last;
#endif
- struct module *owner;
+ struct module *owner;
};

/*