BLK_START_PLUG(9)		 Block Devices		     BLK_START_PLUG(9)

NAME
       blk_start_plug - initialize blk_plug and track it inside the
       task_struct

SYNOPSIS
       void blk_start_plug(struct blk_plug * plug);

ARGUMENTS
       plug
	   The struct blk_plug that needs to be initialized

DESCRIPTION
       Tracking blk_plug inside the task_struct will help with auto-flushing
       the pending I/O should the task end up blocking between blk_start_plug
       and blk_finish_plug. This is important from a performance perspective,
       but also ensures that we don't deadlock. For instance, if the task is
       blocking for a memory allocation, memory reclaim could end up wanting
       to free a page belonging to that request that is currently residing in
       our private plug. By flushing the pending I/O when the process goes to
       sleep, we avoid this kind of deadlock.

COPYRIGHT
Kernel Hackers Manual 3.8.	   June 2014		     BLK_START_PLUG(9)

Vote for polarhome