It isn't necessary any more and the suballocator seems to perform
even better.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Directly use the suballocator to get small chunks of memory.
It's equally fast and doesn't crash when we encounter a GPU reset.
v2: rebased on new SA interface.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
A startover with a new idea for a multiple ring allocator.
Should perform as well as a normal ring allocator as long
as only one ring does somthing, but falls back to a more
complex algorithm if more complex things start to happen.
We store the last allocated bo in last, we always try to allocate
after the last allocated bo. Principle is that in a linear GPU ring
progression was is after last is the oldest bo we allocated and thus
the first one that should no longer be in use by the GPU.
If it's not the case we skip over the bo after last to the closest
done bo if such one exist. If none exist and we are not asked to
block we report failure to allocate.
If we are asked to block we wait on all the oldest fence of all
rings. We just wait for any of those fence to complete.
v2: We need to be able to let hole point to the list_head, otherwise
try free will never free the first allocation of the list. Also
stop calling radeon_fence_signalled more than necessary.
v3: Don't free allocations without considering them as a hole,
otherwise we might lose holes. Also return ENOMEM instead of ENOENT
when running out of fences to wait for. Limit the number of holes
we try for each ring to 3.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Use one wait queue for all rings. When one ring progress, other
likely does to and we are not expecting to have a lot of waiter
anyway.
Also add a fence_wait_any that will wait until the first fence
in the fence array (one fence per ring) is signaled. This allow
to wait on all rings.
v2: some minor cleanups and improvements.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Define the interface without modifying the allocation
algorithm in any way.
v2: rebase on top of fence new uint64 patch
v3: add ring to debugfs output
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Instead of offset + size keep start and end offset directly.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Make the suballocator self containing to locking.
v2: split the bugfix into a seperate patch.
v3: remove some unreleated changes.
Sig-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Instead of hacking the calculation multiple times.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Some callers illegal called fence_wait_next/empty
while holding the ring emission mutex. So don't
relock the mutex in that cases, and move the actual
locking into the fence code.
v2: Don't try to unlock the mutex if it isn't locked.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Using 64bits fence sequence we can directly compare sequence
number to know if a fence is signaled or not. Thus the fence
list became useless, so does the fence lock that mainly
protected the fence list.
Things like ring.ready are no longer behind a lock, this should
be ok as ring.ready is initialized once and will only change
when facing lockup. Worst case is that we return an -EBUSY just
after a successfull GPU reset, or we go into wait state instead
of returning -EBUSY (thus delaying reporting -EBUSY to fence
wait caller).
v2: Remove left over comment, force using writeback on cayman and
newer, thus not having to suffer from possibly scratch reg
exhaustion
v3: Rebase on top of change to uint64 fence patch
v4: Change DCE5 test to force write back on cayman and newer but
also any APU such as PALM or SUMO family
v5: Rebase on top of new uint64 fence patch
v6: Just break if seq doesn't change any more. Use radeon_fence
prefix for all function names. Even if it's now highly optimized,
try avoiding polling to often.
v7: We should never poll the last_seq from the hardware without
waking the sleeping threads, otherwise we might lose events.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This convert fence to use uint64_t sequence number intention is
to use the fact that uin64_t is big enough that we don't need to
care about wrap around.
Tested with and without writeback using 0xFFFFF000 as initial
fence sequence and thus allowing to test the wrap around from
32bits to 64bits.
v2: Add comment about possible race btw CPU & GPU, add comment
stressing that we need 2 dword aligned for R600_WB_EVENT_OFFSET
Read fence sequenc in reverse order of GPU write them so we
mitigate the race btw CPU and GPU.
v3: Drop the need for ring to emit the 64bits fence, and just have
each ring emit the lower 32bits of the fence sequence. We
handle the wrap over 32bits in fence_process.
v4: Just a small optimization: Don't reread the last_seq value
if loop restarts, since we already know its value anyway.
Also start at zero not one for seq value and use pre instead
of post increment in emmit, otherwise wait_empty will deadlock.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
A single global mutex for ring submissions seems sufficient.
Signed-off-by: Christian König <deathsimple@vodafone.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>
We need to sync with the GFX ring as ttm might have schedule bo move
on it and new command scheduled for other ring need to wait for bo
data to be in place.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Reviewed by: Christian König <christian.koenig@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
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Merge tag 'v3.4-rc6' into drm-intel-next
Conflicts:
drivers/gpu/drm/i915/intel_display.c
Ok, this is a fun story of git totally messing things up. There
/shouldn't/ be any conflict in here, because the fixes in -rc6 do only
touch functions that have not been changed in -next.
The offending commits in drm-next are 14415745b2..1fa611065 which
simply move a few functions from intel_display.c to intel_pm.c. The
problem seems to be that git diff gets completely confused:
$ git diff 14415745b2..1fa611065
is a nice mess in intel_display.c, and the diff leaks into totally
unrelated functions, whereas
$git diff --minimal 14415745b2..1fa611065
is exactly what we want.
Unfortunately there seems to be no way to teach similar smarts to the
merge diff and conflict generation code, because with the minimal diff
there really shouldn't be any conflicts. For added hilarity, every
time something in that area changes the + and - lines in the diff move
around like crazy, again resulting in new conflicts. So I fear this
mess will stay with us for a little longer (and might result in
another backmerge down the road).
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
cc1: warning: include/drm: No such file or directory [enabled by default]
It's reproducible if you build with O=/some/obj/dir and W=1.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This was mostly already fixed but this one change is needed to match Kirill's
original submission
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Add the opregion support and bring us in line with the opregion functionality in the
reference driver code. We can't share this with i915 currently because there are
hardcoded assumptions about dev_priv etc in both versions.
[airlied: include opregion.h fix]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Pull x86 fixes form Peter Anvin
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
intel_mid_powerbtn: mark irq as IRQF_NO_SUSPEND
arch/x86/platform/geode/net5501.c: change active_low to 0 for LED driver
x86, relocs: Remove an unused variable
asm-generic: Use __BITS_PER_LONG in statfs.h
x86/amd: Re-enable CPU topology extensions in case BIOS has disabled it
Pull btrfs fixes from Chris Mason:
"The big ones here are a memory leak we introduced in rc1, and a
scheduling while atomic if the transid on disk doesn't match the
transid we expected. This happens for corrupt blocks, or out of date
disks.
It also fixes up the ioctl definition for our ioctl to resolve logical
inode numbers. The __u32 was a merging error and doesn't match what
we ship in the progs."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: avoid sleeping in verify_parent_transid while atomic
Btrfs: fix crash in scrub repair code when device is missing
btrfs: Fix mismatching struct members in ioctl.h
Btrfs: fix page leak when allocing extent buffers
Btrfs: Add properly locking around add_root_to_dirty_list
Setting TIF_IA32 in load_aout_binary() used to be enough; these days
TASK_SIZE is controlled by TIF_ADDR32 and that one doesn't get set
there. Switch to use of set_personality_ia32()...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
verify_parent_transid needs to lock the extent range to make
sure no IO is underway, and so it can safely clear the
uptodate bits if our checks fail.
But, a few callers are using it with spinlocks held. Most
of the time, the generation numbers are going to match, and
we don't want to switch to a blocking lock just for the error
case. This adds an atomic flag to verify_parent_transid,
and changes it to return EAGAIN if it needs to block to
properly verifiy things.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Pull alpha fixes from Matt Turner:
"My alpha tree is back up (after taking quite some time to get my GPG
key signed). It contains just some simple fixes."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha:
alpha: silence 'const' warning in sys_marvel.c
alpha: include module.h to fix modpost on Tsunami
alpha: properly define get/set_rtc_time on Marvel/SMP
alpha: VGA_HOSE depends on VGA_CONSOLE
The test in pdc_console_tty_close '!tty->count' was always wrong
because tty->count is decremented after tty->ops->close is called and
thus can never be zero. Hence the 'then' branch was never executed and
the timer never deleted.
This did not matter until commit 5dd5bc40f3 ("TTY: pdc_cons, use
tty_port"). There we needed to set TTY in tty_port to NULL, but this
never happened due to the bug above.
So change the test to really trigger at the last close by changing the
condition to 'tty->count == 1'.
Well, the driver should not touch tty->count at all. It should use
tty_port->count and count open count there itself.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-and-tested-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As good as nothing exciting here; just a few trivial fixes for
various ASoC stuff.
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Merge tag 'sound-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound sound fixes from Takashi Iwai:
"As good as nothing exciting here; just a few trivial fixes for various
ASoC stuff."
* tag 'sound-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ASoC: omap-pcm: Free dma buffers in case of error.
ASoC: s3c2412-i2s: Fix dai registration
ASoC: wm8350: Don't use locally allocated codec struct
ASoC: tlv312aic23: unbreak resume
ASoC: bf5xx-ssm2602: Set DAI format
ASoC: core: check of_property_count_strings failure
ASoC: dt: sgtl5000.txt: Add description for 'reg' field
ASoC: wm_hubs: Make sure we don't disable differential line outputs
Pull an ACPI patch from Len Brown:
"It fixes a D3 issue new in 3.4-rc1."
By Lin Ming via Len Brown:
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
ACPI: Fix D3hot v D3cold confusion
Currently, we'll try mounting any device who's major device number is
UNNAMED_MAJOR as NFS root. This would happen for non-NFS devices as
well (such as 9p devices) but it wouldn't cause any issues since
mounting the device as NFS would fail quickly and the code proceeded to
doing the proper mount:
[ 101.522716] VFS: Unable to mount root fs via NFS, trying floppy.
[ 101.534499] VFS: Mounted root (9p filesystem) on device 0:18.
Commit 6829a048102a ("NFS: Retry mounting NFSROOT") introduced retries
when mounting NFS root, which means that now we don't immediately fail
and instead it takes an additional 90+ seconds until we stop retrying,
which has revealed the issue this patch fixes.
This meant that it would take an additional 90 seconds to boot when
we're not using a device type which gets detected in order before NFS.
This patch modifies the NFS type check to require device type to be
'Root_NFS' instead of requiring the device to have an UNNAMED_MAJOR
major. This makes boot process cleaner since we now won't go through
the NFS mounting code at all when the device isn't an NFS root
("/dev/nfs").
Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nothing terribly exciting here, a bunch of small and simple fixes
scattered around the place.
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Merge tag 'asoc-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for 3.4
Nothing terribly exciting here, a bunch of small and simple fixes
scattered around the place.
Before this patch, ACPI_STATE_D3 incorrectly referenced D3hot
in some places, but D3cold in other places.
After this patch, ACPI_STATE_D3 always means ACPI_STATE_D3_COLD;
and all references to D3hot use ACPI_STATE_D3_HOT.
ACPI's _PR3 method is used to enter both D3hot and D3cold states.
What distinguishes D3hot from D3cold is the presence _PR3
(Power Resources for D3hot) If these resources are all ON,
then the state is D3hot. If _PR3 is not present,
or all _PR0 resources for the devices are OFF,
then the state is D3cold.
This patch applies after Linux-3.4-rc1.
A future syntax cleanup may remove ACPI_STATE_D3
to emphasize that it always means ACPI_STATE_D3_COLD.
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Aaron Lu <aaron.lu@amd.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Commit ec81aecb29 ("hfs: fix a potential buffer overflow") fixed a few
potential buffer overflows in the hfs filesystem. But as Timo Warns
pointed out, these changes also need to be made on the hfsplus
filesystem as well.
Reported-by: Timo Warns <warns@pre-sense.de>
Acked-by: WANG Cong <amwang@redhat.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Sage Weil <sage@newdream.net>
Cc: Eugene Teo <eteo@redhat.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Dave Anderson <anderson@redhat.com>
Cc: stable <stable@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull timer fix from Thomas Gleixner.
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rtc: Fix possible null pointer dereference in rtc-mpc5121.c
Pull CIFS fixes from Steve French.
* git://git.samba.org/sfrench/cifs-2.6:
fs/cifs: fix parsing of dfs referrals
cifs: make sure we ignore the credentials= and cred= options
[CIFS] Update cifs version to 1.78
cifs - check S_AUTOMOUNT in revalidate
cifs: add missing initialization of server->req_lock
cifs: don't cap ra_pages at the same level as default_backing_dev_info
CIFS: Fix indentation in cifs_show_options
Remove myself as cpufreq maintainer.
x86 driver changes can go through the regular x86/ACPI trees.
ARM driver changes through the ARM trees.
cpufreq core changes are rare these days, and can just go to lkml/direct.
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The normal read_seqcount_begin() function will wait for any current
writers to exit their critical region by looping until the sequence
count is even.
That "wait for sequence count to stabilize" is the right thing to do if
the read-locker will just retry the whole operation on contention: no
point in doing a potentially expensive reader sequence if we know at the
beginning that we'll just end up re-doing it all.
HOWEVER. Some users don't actually retry the operation, but instead
will abort and do the operation with proper locking. So the sequence
count case may be the optimistic quick case, but in the presense of
writers you may want to do full locking in order to guarantee forward
progress. The prime example of this would be the RCU name lookup.
And in that case, you may well be better off without the "retry early",
and are in a rush to instead get to the failure handling. Thus this
"raw" interface that just returns the sequence number without testing it
- it just forces the low bit to zero so that read_seqcount_retry() will
always fail such a "active concurrent writer" scenario.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We really need to use a ACCESS_ONCE() on the sequence value read in
__read_seqcount_begin(), because otherwise the compiler might end up
reloading the value in between the test and the return of it. As a
result, it might end up returning an odd value (which means that a write
is in progress).
If the reader is then fast enough that that odd value is still the
current one when the read_seqcount_retry() is done, we might end up with
a "successful" read sequence, even despite the concurrent write being
active.
In practice this probably never really happens - there just isn't
anything else going on around the read of the sequence count, and the
common case is that we end up having a read barrier immediately
afterwards.
So the code sequence in which gcc might decide to reaload from memory is
small, and there's no reason to believe it would ever actually do the
reload. But if the compiler ever were to decide to do so, it would be
incredibly annoying to debug. Let's just make sure.
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
