Commit 9ebb4d70 authored by Ming Lei's avatar Ming Lei Committed by Martin K. Petersen
Browse files

scsi: core: Put hot fields of scsi_host_template in one cacheline 

The following three fields of scsi_host_template are referenced in the SCSI
I/O submission hot path. Put them together in one cacheline:

 - cmd_size

 - queuecommand

 - commit_rqs

Link: https://lore.kernel.org/r/20210122023317.687987-10-ming.lei@redhat.com


Cc: Omar Sandoval <osandov@fb.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Sumanesh Samanta <sumanesh.samanta@broadcom.com>
Cc: Ewan D. Milne <emilne@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Tested-by: default avatarSumanesh Samanta <sumanesh.samanta@broadcom.com>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 2a5a24aa

include/scsi/scsi_host.h

+39 −33
Original line number Diff line number Diff line
@@ -30,40 +30,15 @@ struct scsi_transport_template; 
#define MODE_TARGET 0x02



struct scsi_host_template {

	struct module *module;

	const char *name;



	/*

	 * The info function will return whatever useful information the

	 * developer sees fit.  If not provided, then the name field will

	 * be used instead.

	 *

	 * Status: OPTIONAL

	 * Put fields referenced in IO submission path together in

	 * same cacheline

	 */

	const char *(* info)(struct Scsi_Host *);



	/*

	 * Ioctl interface

	 *

	 * Status: OPTIONAL

	 */

	int (*ioctl)(struct scsi_device *dev, unsigned int cmd,

		     void __user *arg);





#ifdef CONFIG_COMPAT

	/* 

	 * Compat handler. Handle 32bit ABI.

	 * When unknown ioctl is passed return -ENOIOCTLCMD.

	 *

	 * Status: OPTIONAL

	 * Additional per-command data allocated for the driver.

	 */

	int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,

			    void __user *arg);

#endif



	int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);

	int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);

	unsigned int cmd_size;



	/*

	 * The queuecommand function is used to queue up a scsi
@@ -111,6 +86,41 @@ struct scsi_host_template { 
	 */

	void (*commit_rqs)(struct Scsi_Host *, u16);



	struct module *module;

	const char *name;



	/*

	 * The info function will return whatever useful information the

	 * developer sees fit.  If not provided, then the name field will

	 * be used instead.

	 *

	 * Status: OPTIONAL

	 */

	const char *(*info)(struct Scsi_Host *);



	/*

	 * Ioctl interface

	 *

	 * Status: OPTIONAL

	 */

	int (*ioctl)(struct scsi_device *dev, unsigned int cmd,

		     void __user *arg);





#ifdef CONFIG_COMPAT

	/*

	 * Compat handler. Handle 32bit ABI.

	 * When unknown ioctl is passed return -ENOIOCTLCMD.

	 *

	 * Status: OPTIONAL

	 */

	int (*compat_ioctl)(struct scsi_device *dev, unsigned int cmd,

			    void __user *arg);

#endif



	int (*init_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);

	int (*exit_cmd_priv)(struct Scsi_Host *shost, struct scsi_cmnd *cmd);



	/*

	 * This is an error handling strategy routine.  You don't need to

	 * define one of these if you don't want to - there is a default
@@ -484,10 +494,6 @@ struct scsi_host_template { 
	 */

	u64 vendor_id;



	/*

	 * Additional per-command data allocated for the driver.

	 */

	unsigned int cmd_size;

	struct scsi_host_cmd_pool *cmd_pool;



	/* Delay for runtime autosuspend */