nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

spi: Reorder fields in 'struct spi_message'

Browse source 
Group some variables based on their sizes to reduce hole and avoid padding.
On x86_64, this shrinks the size from 112 to 96 bytes.

This should have no real impact on memory allocation because 'struct
spi_message' is mostly used on stack, but it can save a few cycles
when the structure is initialized with spi_message_init() and co.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Link: https://lore.kernel.org/r/c112aad16eb47808e1ec10abd87b3d273c969a68.1677704283.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Christophe JAILLET 2023-03-01 21:58:52 +01:00 committed by Mark Brown
parent 8c220e6c6d
commit ae2ade4ba5
No known key found for this signature in database
GPG key ID: 24D68B725D5487D0
1 changed files with 4 additions and 4 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

8
include/linux/spi/spi.h
View file

@ -1093,6 +1093,9 @@ struct spi_message {
unsigned is_dma_mapped:1; unsigned is_dma_mapped:1;
/* spi_prepare_message() was called for this message */
bool prepared;
/* REVISIT: we might want a flag affecting the behavior of the /* REVISIT: we might want a flag affecting the behavior of the
* last transfer ... allowing things like "read 16 bit length L" * last transfer ... allowing things like "read 16 bit length L"
* immediately followed by "read L bytes". Basically imposing * immediately followed by "read L bytes". Basically imposing
@ -1105,11 +1108,11 @@ struct spi_message {
*/ */
/* Completion is reported through a callback */ /* Completion is reported through a callback */
int status;
void (*complete)(void *context); void (*complete)(void *context);
void *context; void *context;
unsigned frame_length; unsigned frame_length;
unsigned actual_length; unsigned actual_length;
int status;
/* For optional use by whatever driver currently owns the /* For optional use by whatever driver currently owns the
* spi_message ... between calls to spi_async and then later * spi_message ... between calls to spi_async and then later
@ -1120,9 +1123,6 @@ struct spi_message {
/* List of spi_res reources when the spi message is processed */ /* List of spi_res reources when the spi message is processed */
struct list_head resources; struct list_head resources;
/* spi_prepare_message() was called for this message */
bool prepared;
}; };
static inline void spi_message_init_no_memset(struct spi_message *m) static inline void spi_message_init_no_memset(struct spi_message *m)