Commit 8e6b8594 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

USB: usb.h: tweak struct urb to remove wasted space 



By moving one field around in 'struct urb' we reduce the size of the
structure by 8 bytes.

Before the patch on x86_64 the overall size of the structure as reported
by pahole was:
	/* size: 192, cachelines: 3, members: 30 */
	/* sum members: 184, holes: 2, sum holes: 8 */
After the patch we now have:
	/* size: 184, cachelines: 3, members: 30 */
	/* last cacheline: 56 bytes */

Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 9e98c678

include/linux/usb.h

+1 −1
Original line number Diff line number Diff line
@@ -1545,10 +1545,10 @@ typedef void (*usb_complete_t)(struct urb *); 
struct urb {

	/* private: usb core and host controller only fields in the urb */

	struct kref kref;		/* reference count of the URB */

	int unlinked;			/* unlink error code */

	void *hcpriv;			/* private data for host controller */

	atomic_t use_count;		/* concurrent submissions counter */

	atomic_t reject;		/* submissions will fail */

	int unlinked;			/* unlink error code */



	/* public: documented fields in the urb that can be used by drivers */

	struct list_head urb_list;	/* list head for use by the urb's