target: Shrink struct se_cmd by rearranging fields

On x86-64, these changes reduce the struct size from 528 bytes to 496
bytes.  We save a cacheline and get under 512 bytes for better packing.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Acked-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Roland Dreier 2015-07-21 17:45:33 -07:00 committed by Nicholas Bellinger
parent 9c31820b6a
commit 915270c3ca

View File

@ -439,6 +439,9 @@ struct se_cmd {
u8 scsi_asc;
u8 scsi_ascq;
u16 scsi_sense_length;
unsigned cmd_wait_set:1;
unsigned unknown_data_length:1;
bool state_active:1;
u64 tag; /* SAM command identifier aka task tag */
/* Delay for ALUA Active/NonOptimized state access in milliseconds */
int alua_nonop_delay;
@ -450,8 +453,6 @@ struct se_cmd {
unsigned int map_tag;
/* Transport protocol dependent state, see transport_state_table */
enum transport_state_table t_state;
unsigned cmd_wait_set:1;
unsigned unknown_data_length:1;
/* See se_cmd_flags_table */
u32 se_cmd_flags;
/* Total size in bytes associated with command */
@ -471,7 +472,6 @@ struct se_cmd {
struct se_tmr_req *se_tmr_req;
struct list_head se_cmd_list;
struct completion cmd_wait_comp;
struct kref cmd_kref;
const struct target_core_fabric_ops *se_tfo;
sense_reason_t (*execute_cmd)(struct se_cmd *);
sense_reason_t (*transport_complete_callback)(struct se_cmd *, bool);
@ -491,6 +491,7 @@ struct se_cmd {
#define CMD_T_REQUEST_STOP (1 << 8)
#define CMD_T_BUSY (1 << 9)
spinlock_t t_state_lock;
struct kref cmd_kref;
struct completion t_transport_stop_comp;
struct work_struct work;
@ -503,8 +504,10 @@ struct se_cmd {
struct scatterlist *t_bidi_data_sg;
unsigned int t_bidi_data_nents;
/* Used for lun->lun_ref counting */
int lun_ref_active;
struct list_head state_list;
bool state_active;
/* old task stop completion, consider merging with some of the above */
struct completion task_stop_comp;
@ -512,20 +515,17 @@ struct se_cmd {
/* backend private data */
void *priv;
/* Used for lun->lun_ref counting */
int lun_ref_active;
/* DIF related members */
enum target_prot_op prot_op;
enum target_prot_type prot_type;
u8 prot_checks;
bool prot_pto;
u32 prot_length;
u32 reftag_seed;
struct scatterlist *t_prot_sg;
unsigned int t_prot_nents;
sense_reason_t pi_err;
sector_t bad_sector;
bool prot_pto;
};
struct se_ua {