linux/include
Marek Olšák dfadbbdb57 drm/ttm: add a way to bo_wait for either the last read or last write
Sometimes we want to know whether a buffer is busy and wait for it (bo_wait).
However, sometimes it would be more useful to be able to query whether
a buffer is busy and being either read or written, and wait until it's stopped
being either read or written. The point of this is to be able to avoid
unnecessary waiting, e.g. if a GPU has written something to a buffer and is now
reading that buffer, and a CPU wants to map that buffer for read, it needs to
only wait for the last write. If there were no write, there wouldn't be any
waiting needed.

This, or course, requires user space drivers to send read/write flags
with each relocation (like we have read/write domains in radeon, so we can
actually use those for something useful now).

Now how this patch works:

The read/write flags should passed to ttm_validate_buffer. TTM maintains
separate sync objects of the last read and write for each buffer, in addition
to the sync object of the last use of a buffer. ttm_bo_wait then operates
with one the sync objects.

Signed-off-by: Marek Olšák <maraeo@gmail.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-08-31 19:25:35 +01:00
..
acpi Merge branch 'apei-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2011-08-03 21:53:27 -10:00
asm-generic All Arch: remove linkage for sys_nfsservctl system call 2011-08-26 15:09:58 -07:00
crypto
drm drm/ttm: add a way to bo_wait for either the last read or last write 2011-08-31 19:25:35 +01:00
keys
linux All Arch: remove linkage for sys_nfsservctl system call 2011-08-26 15:09:58 -07:00
math-emu
media [media] V4L: initial driver for ov5642 CMOS sensor 2011-07-27 17:56:09 -03:00
mtd
net ipv4: route non-local sources for raw socket 2011-08-07 22:52:32 -07:00
pcmcia Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2011-07-31 06:23:08 -10:00
rdma atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
rxrpc atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
scsi Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd 2011-08-06 22:56:03 -07:00
sound ASoC: omap: Update e-mail address of Jarkko Nikula 2011-08-12 11:45:10 +09:00
target target: Make standard INQUIRY return 'not connected' for tpg_virt_lun0 2011-08-22 19:25:35 +00:00
trace Merge branch 'for-linus' of git://git.kernel.dk/linux-block 2011-08-19 10:47:07 -07:00
video OMAP: DSS2: Remove unused opt_clock_available 2011-07-25 10:22:05 +03:00
xen xen/balloon: memory hotplug support for Xen balloon driver 2011-07-25 20:57:08 -07:00
Kbuild