Mike Snitzer bfebd1cdb4 dm: add full blk-mq support to request-based DM ... Commit e5863d9ad ("dm: allocate requests in target when stacking on blk-mq devices") served as the first step toward fully utilizing blk-mq in request-based DM -- it enabled stacking an old-style (request_fn) request_queue ontop of the underlying blk-mq device(s). That first step didn't improve performance of DM multipath ontop of fast blk-mq devices (e.g. NVMe) because the top-level old-style request_queue was severely limited by the queue_lock. The second step offered here enables stacking a blk-mq request_queue ontop of the underlying blk-mq device(s). This unlocks significant performance gains on fast blk-mq devices, Keith Busch tested on his NVMe testbed and offered this really positive news: "Just providing a performance update. All my fio tests are getting roughly equal performance whether accessed through the raw block device or the multipath device mapper (~470k IOPS). I could only push ~20% of the raw iops through dm before this conversion, so this latest tree is looking really solid from a performance standpoint." Signed-off-by: Mike Snitzer <snitzer@redhat.com> Tested-by: Keith Busch <keith.busch@intel.com>		2015-04-15 12:10:16 -04:00
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asm-generic	vfs: renumber FMODE_NONOTIFY and add to uniqueness check	2015-01-08 15:10:52 -08:00
drm	Merge tag 'topic/drm-misc-2015-02-06' of git://anongit.freedesktop.org/drm-intel into drm-next	2015-02-11 15:33:02 +10:00
linux	dm: add full blk-mq support to request-based DM	2015-04-15 12:10:16 -04:00
misc	cxl: Add documentation for userspace APIs	2014-10-08 20:16:19 +11:00
mtd
rdma	IB/core: Add on demand paging caps to ib_uverbs_ex_query_device	2015-02-18 08:36:26 -08:00
scsi
sound	ALSA: usx2y: Move UAPI definition into include/uapi/sound/usb_stream.h	2015-01-28 17:33:49 +01:00
video
xen
Kbuild	cxl: Add userspace header file	2014-10-08 20:15:57 +11:00