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regmap: Reorder fields in 'struct regmap_config' to save some memory

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On x86_64 and allmodconfig, this shrinks the size of 'struct regmap_config'
from 328 to 312 bytes.

This is usually a win, because this structure is used as a static global
variable.

When moving the kerneldoc fields, I've tried to keep the layout as
consistent as possible, which is not really easy!

Before:
	/* size: 328, cachelines: 6, members: 55 */
	/* sum members: 296, holes: 6, sum holes: 25 */
	/* padding: 7 */
	/* last cacheline: 8 bytes */

After:
	/* size: 312, cachelines: 5, members: 55 */
	/* sum members: 296, holes: 5, sum holes: 16 */
	/* last cacheline: 56 bytes */

For the records, this is also widely used:
	$git grep static.*regmap_config | wc -l
	1327

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/5e039cd8fe415dd7ab3169948c08a5311db9fb9a.1715024007.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Christophe JAILLET 2024-05-06 21:33:33 +02:00 committed by Mark Brown
parent 991b5e2aad
commit 9b1fe05104
No known key found for this signature in database
GPG Key ID: 24D68B725D5487D0
1 changed files with 31 additions and 31 deletions
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62
include/linux/regmap.h
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@ -297,15 +297,6 @@ typedef void (*regmap_unlock)(void *);
* performed on such table (a register is no increment
* readable if it belongs to one of the ranges specified
* by rd_noinc_table).
* @disable_locking: This regmap is either protected by external means or
* is guaranteed not to be accessed from multiple threads.
* Don't use any locking mechanisms.
* @lock: Optional lock callback (overrides regmap's default lock
* function, based on spinlock or mutex).
* @unlock: As above for unlocking.
* @lock_arg: this field is passed as the only argument of lock/unlock
* functions (ignored in case regular lock/unlock functions
* are not overridden).
* @reg_read: Optional callback that if filled will be used to perform
* all the reads from the registers. Should only be provided for
* devices whose read operation cannot be represented as a simple
@ -323,6 +314,7 @@ typedef void (*regmap_unlock)(void *);
* @write: Same as above for writing.
* @max_raw_read: Max raw read size that can be used on the device.
* @max_raw_write: Max raw write size that can be used on the device.
* @can_sleep: Optional, specifies whether regmap operations can sleep.
* @fast_io: Register IO is fast. Use a spinlock instead of a mutex
* to perform locking. This field is ignored if custom lock/unlock
* functions are used (see fields lock/unlock of struct regmap_config).
@ -331,6 +323,15 @@ typedef void (*regmap_unlock)(void *);
* Use it only for "no-bus" cases.
* @io_port: Support IO port accessors. Makes sense only when MMIO vs. IO port
* access can be distinguished.
* @disable_locking: This regmap is either protected by external means or
* is guaranteed not to be accessed from multiple threads.
* Don't use any locking mechanisms.
* @lock: Optional lock callback (overrides regmap's default lock
* function, based on spinlock or mutex).
* @unlock: As above for unlocking.
* @lock_arg: This field is passed as the only argument of lock/unlock
* functions (ignored in case regular lock/unlock functions
* are not overridden).
* @max_register: Optional, specifies the maximum valid register address.
* @max_register_is_0: Optional, specifies that zero value in @max_register
* should be taken into account. This is a workaround to
@ -373,21 +374,20 @@ typedef void (*regmap_unlock)(void *);
* @reg_defaults_raw: Power on reset values for registers (for use with
* register cache support).
* @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
* @reg_format_endian: Endianness for formatted register addresses. If this is
* DEFAULT, the @reg_format_endian_default value from the
* regmap bus is used.
* @val_format_endian: Endianness for formatted register values. If this is
* DEFAULT, the @reg_format_endian_default value from the
* regmap bus is used.
*
* @ranges: Array of configuration entries for virtual address ranges.
* @num_ranges: Number of range configuration entries.
* @use_hwlock: Indicate if a hardware spinlock should be used.
* @use_raw_spinlock: Indicate if a raw spinlock should be used.
* @hwlock_id: Specify the hardware spinlock id.
* @hwlock_mode: The hardware spinlock mode, should be HWLOCK_IRQSTATE,
* HWLOCK_IRQ or 0.
* @can_sleep: Optional, specifies whether regmap operations can sleep.
* @reg_format_endian: Endianness for formatted register addresses. If this is
* DEFAULT, the @reg_format_endian_default value from the
* regmap bus is used.
* @val_format_endian: Endianness for formatted register values. If this is
* DEFAULT, the @reg_format_endian_default value from the
* regmap bus is used.
*
* @ranges: Array of configuration entries for virtual address ranges.
* @num_ranges: Number of range configuration entries.
*/
struct regmap_config {
const char *name;
@ -406,11 +406,6 @@ struct regmap_config {
bool (*writeable_noinc_reg)(struct device *dev, unsigned int reg);
bool (*readable_noinc_reg)(struct device *dev, unsigned int reg);
bool disable_locking;
regmap_lock lock;
regmap_unlock unlock;
void *lock_arg;
int (*reg_read)(void *context, unsigned int reg, unsigned int *val);
int (*reg_write)(void *context, unsigned int reg, unsigned int val);
int (*reg_update_bits)(void *context, unsigned int reg,
@ -422,9 +417,16 @@ struct regmap_config {
size_t max_raw_read;
size_t max_raw_write;
bool can_sleep;
bool fast_io;
bool io_port;
bool disable_locking;
regmap_lock lock;
regmap_unlock unlock;
void *lock_arg;
unsigned int max_register;
bool max_register_is_0;
const struct regmap_access_table *wr_table;
@ -448,18 +450,16 @@ struct regmap_config {
bool use_relaxed_mmio;
bool can_multi_write;
enum regmap_endian reg_format_endian;
enum regmap_endian val_format_endian;
const struct regmap_range_cfg *ranges;
unsigned int num_ranges;
bool use_hwlock;
bool use_raw_spinlock;
unsigned int hwlock_id;
unsigned int hwlock_mode;
bool can_sleep;
enum regmap_endian reg_format_endian;
enum regmap_endian val_format_endian;
const struct regmap_range_cfg *ranges;
unsigned int num_ranges;
};
/**