Commit d00106bb authored by Anna-Maria Behnsen's avatar Anna-Maria Behnsen Committed by Thomas Gleixner
Browse files

vdso: Add comment about reason for vdso struct ordering 



struct vdso_data is optimized for fast access to the often required struct
members. The optimization is not documented in the struct description but
it should be kept in mind, when working with the vdso_data struct.
                                                                                                                                                                                                                                             
Add a comment to the struct description.

Signed-off-by: default avatarAnna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarVincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20240701-vdso-cleanup-v1-2-36eb64e7ece2@linutronix.de
parent f48955e0

include/vdso/datapage.h

+4 −0
Original line number Diff line number Diff line
@@ -77,6 +77,10 @@ struct vdso_timestamp { 
 * vdso_data will be accessed by 64 bit and compat code at the same time

 * so we should be careful before modifying this structure.

 *

 * The ordering of the struct members is optimized to have fast access to the

 * often required struct members which are related to CLOCK_REALTIME and

 * CLOCK_MONOTONIC. This information is stored in the first cache lines.

 *

 * @basetime is used to store the base time for the system wide time getter

 * VVAR page.

 *