soundwire: optimize sdw_stream_runtime memory layout
authorPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Thu, 3 Oct 2024 07:06:38 +0000 (15:06 +0800)
committerVinod Koul <vkoul@kernel.org>
Thu, 3 Oct 2024 07:58:50 +0000 (13:28 +0530)
commit444d6824a4feca142b0a57095a2f1f1bda98e2ab
treea726e5d7a7ef15f76719ba298acaa490ad04eaa7
parent093227bc53a023991ba04315f42839a22b613113
soundwire: optimize sdw_stream_runtime memory layout

pahole suggestion: swap position of 'm_rt_count'

before: pahole -C sdw_stream_runtime drivers/soundwire/soundwire-bus.ko
struct sdw_stream_runtime {
const char  *              name;                 /*     0     8 */
struct sdw_stream_params   params;               /*     8    12 */
enum sdw_stream_state      state;                /*    20     4 */
enum sdw_stream_type       type;                 /*    24     4 */

/* XXX 4 bytes hole, try to pack */

struct list_head           master_list;          /*    32    16 */
int                        m_rt_count;           /*    48     4 */

/* size: 56, cachelines: 1, members: 6 */
/* sum members: 48, holes: 1, sum holes: 4 */
/* padding: 4 */
/* last cacheline: 56 bytes */
};

after: pahole --reorganize -C sdw_stream_runtime drivers/soundwire/soundwire-bus.ko
struct sdw_stream_runtime {
const char  *              name;                 /*     0     8 */
struct sdw_stream_params   params;               /*     8    12 */
enum sdw_stream_state      state;                /*    20     4 */
enum sdw_stream_type       type;                 /*    24     4 */
int                        m_rt_count;           /*    28     4 */
struct list_head           master_list;          /*    32    16 */

/* size: 48, cachelines: 1, members: 6 */
/* last cacheline: 48 bytes */
};   /* saved 8 bytes! */

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20241003070650.62787-3-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
include/linux/soundwire/sdw.h