Improves cacheline transfer flow of available ring header.
Virtqueues are implemented as a pair of rings, one producer->consumer
avail ring and one consumer->producer used ring; preceding the
avail ring in memory are two contiguous u16 fields -- avail->flags
and avail->idx. A producer posts work by writing to avail->idx and
a consumer reads avail->idx.
The flags and idx fields only need to be written by a producer CPU
and only read by a consumer CPU; when the producer and consumer are
running on different CPUs and the virtio_ring code is structured to
only have source writes/sink reads, we can continuously transfer the
avail header cacheline between 'M' states between cores. This flow
optimizes core -> core bandwidth on certain CPUs.
(see: "Software Optimization Guide for AMD Family 15h Processors",
Section 11.6; similar language appears in the 10h guide and should
apply to CPUs w/ exclusive caches, using LLC as a transfer cache)
Unfortunately the existing virtio_ring code issued reads to the
avail->idx and read-modify-writes to avail->flags on the producer.
This change shadows the flags and index fields in producer memory;
the vring code now reads from the shadows and only ever writes to
avail->flags and avail->idx, allowing the cacheline to transfer
core -> core optimally.
In a concurrent version of vring_bench, the time required for
10,000,000 buffer checkout/returns was reduced by ~2% (average
across many runs) on an AMD Piledriver (15h) CPU:
(w/o shadowing):
Performance counter stats for './vring_bench':
5,451,082,016 L1-dcache-loads
...
2.221477739 seconds time elapsed
(w/ shadowing):
Performance counter stats for './vring_bench':
5,405,701,361 L1-dcache-loads
...
2.168405376 seconds time elapsed
The further away (in a NUMA sense) virtio producers and consumers are
from each other, the more we expect to benefit. Physical implementations
of virtio devices and implementations of virtio where the consumer polls
vring avail indexes (vhost) should also benefit.
Signed-off-by: Venkatesh Srinivas <venkateshs@google.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
b92b1b89a3 ("virtio: force vring descriptors to be allocated from
lowmem") tried to exclude highmem pages for descriptors so it cleared
__GFP_HIGHMEM from a given gfp mask. The patch also cleared __GFP_HIGH
which doesn't make much sense for this fix because __GFP_HIGH only
controls access to memory reserves and it doesn't have any influence
on the zone selection. Some of the call paths use GFP_ATOMIC and
dropping __GFP_HIGH will reduce their changes for success because the
lack of access to memory reserves.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Mel Gorman <mgorman@techsingularity.net>
commit cf561f0d2e ("virtio: introduce
virtio_is_little_endian() helper") changed byteswap logic to
skip feature bit checks for LE platforms, but didn't
update tools/virtio, so vring_bench started failing.
Update the copy under tools/virtio/ (TODO: find a way to avoid this code
duplication).
Cc: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The virtio core uses a static ida named virtio_index_ida for
assigning index numbers to virtio devices during registration.
The ida core may allocate some internal idr cache layers and
an ida bitmap upon any ida allocation, and all these layers are
truely freed only upon the ida destruction. The virtio_index_ida
is not destroyed at present, leading to a memory leak when using
the virtio core as a module and atleast one virtio device is
registered and unregistered.
Fix this by invoking ida_destroy() in the virtio core module
exit.
Cc: stable@vger.kernel.org
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
commit 5d9a07b0de ("vhost: relax used
address alignment") fixed the alignment for the used virtual address,
but not for the physical address used for logging.
That's a mistake: alignment should clearly be the same for virtual and
physical addresses,
Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Once virtio starts using the DMA API, we won't be able to safely DMA
from the stack. virtio-net does a couple of config DMA requests
from small stack buffers -- switch to using dynamically-allocated
memory.
This should have no effect on any performance-critical code paths.
Reported-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Andy Lutomirski <luto@kernel.org>
The ioctl IOC_LIBCFS_PING_TEST has not been used in ages. The recent
nidstring changes which moved all the nidstring operations from libcfs
to the LNet layer but this ioctl code was still using an nidstring
operation that was causing a circular dependency loop between libcfs and
LNet.
Signed-off-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs fixes from Al Viro:
"A couple of fixes (-stable fodder) + dead code removal after the
overlayfs fix.
I agree that it's better to separate from the fix part to make
backporting easier, but IMO it's not worth delaying said dead code
removal until the next window"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
Don't reset ->total_link_count on nested calls of vfs_path_lookup()
ovl: get rid of the dead code left from broken (and disabled) optimizations
ovl: fix permission checking for setattr
we already zero it on outermost set_nameidata(), so initialization in
path_init() is pointless and wrong. The same DoS exists on pre-4.2
kernels, but there a slightly different fix will be needed.
Cc: stable@vger.kernel.org # v4.2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[Al Viro] The bug is in being too enthusiastic about optimizing ->setattr()
away - instead of "copy verbatim with metadata" + "chmod/chown/utimes"
(with the former being always safe and the latter failing in case of
insufficient permissions) it tries to combine these two. Note that copyup
itself will have to do ->setattr() anyway; _that_ is where the elevated
capabilities are right. Having these two ->setattr() (one to set verbatim
copy of metadata, another to do what overlayfs ->setattr() had been asked
to do in the first place) combined is where it breaks.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull scheduler fixes from Thomas Gleixner:
"This updates contains the following changes:
- Fix a signal handling regression in the bit wait functions.
- Avoid false positive warnings in the wakeup path.
- Initialize the scheduler root domain properly.
- Handle gtime calculations in proc/$PID/stat proper.
- Add more documentation for the barriers in try_to_wake_up().
- Fix a subtle race in try_to_wake_up() which might cause a task to
be scheduled on two cpus
- Compile static helper function only when it is used"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Fix an SMP ordering race in try_to_wake_up() vs. schedule()
sched/core: Better document the try_to_wake_up() barriers
sched/cputime: Fix invalid gtime in proc
sched/core: Clear the root_domain cpumasks in init_rootdomain()
sched/core: Remove false-positive warning from wake_up_process()
sched/wait: Fix signal handling in bit wait helpers
sched/rt: Hide the push_irq_work_func() declaration
Pull x86 fixes from Thoma Gleixner:
"Another round of fixes for x86:
- Move the initialization of the microcode driver to late_initcall to
make sure everything that init function needs is available.
- Make sure that lockdep knows about interrupts being off in the
entry code before calling into c-code.
- Undo the cpu hotplug init delay regression.
- Use the proper conditionals in the mpx instruction decoder.
- Fixup restart_syscall for x32 tasks.
- Fix the hugepage regression on PAE kernels which was introduced
with the latest PAT changes"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/signal: Fix restart_syscall number for x32 tasks
x86/mpx: Fix instruction decoder condition
x86/mm: Fix regression with huge pages on PAE
x86 smpboot: Re-enable init_udelay=0 by default on modern CPUs
x86/entry/64: Fix irqflag tracing wrt context tracking
x86/microcode: Initialize the driver late when facilities are up
This is quite a bumper crop of fixes: Three from Arnd correcting various build
issues in some configurations, a lock recursion in qla2xxx. Two potentially
exploitable issues in hpsa and mvsas, a potential null deref in st, A revert
of a bdi registration fix that turned out to cause even more problems, a set
of fixes to allow people who only defined MPT2SAS to still work after the
mpt2/mpt3sas merger and a couple of fixes for issues turned up by the hyper-v
storvsc driver.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
iQEcBAABAgAGBQJWY8fDAAoJEDeqqVYsXL0MPhwH/Rs05LUU2vnlaZDdDpH5zY56
YQgKh5duF+ZH+Y4NxX5kkLLo05wpE6xD5xp2yzzmnjTA0Uf/yLVHNdb5D6tRZgSo
mZjAX+/wGDb/ErwvwTk/K2mhEvB0iZJJVMyWcG3F9dKgciRCF/p1Gn5EarGmc+vM
w/9xrs1j24Pw7ipHgBj9zU13w+SPMI7LunR0oYL9CJg24jgXG9sAbrwLkox5kHLo
FFBCrZhev1mzFKa1C+Ln3s0iSf0yEQMd4khzPJAUElkw812PZ7I6r4bCP0ZPKDed
JR8zex9jo77RyWZwA7fIathA0/ujv0AeIRXgvzb0/io1Yk577r98vt+S3koQVK8=
=ptgb
-----END PGP SIGNATURE-----
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is quite a bumper crop of fixes: three from Arnd correcting
various build issues in some configurations, a lock recursion in
qla2xxx. Two potentially exploitable issues in hpsa and mvsas, a
potential null deref in st, a revert of a bdi registration fix that
turned out to cause even more problems, a set of fixes to allow people
who only defined MPT2SAS to still work after the mpt2/mpt3sas merger
and a couple of fixes for issues turned up by the hyper-v storvsc
driver"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
mpt3sas: fix Kconfig dependency problem for mpt2sas back compatibility
Revert "scsi: Fix a bdi reregistration race"
mpt3sas: Add dummy Kconfig option for backwards compatibility
Fix a memory leak in scsi_host_dev_release()
block/sd: Fix device-imposed transfer length limits
scsi_debug: fix prevent_allow+verify regressions
MAINTAINERS: Add myself as co-maintainer of the SCSI subsystem.
sd: Make discard granularity match logical block size when LBPRZ=1
scsi: hpsa: select CONFIG_SCSI_SAS_ATTR
scsi: advansys needs ISA dma api for ISA support
scsi_sysfs: protect against double execution of __scsi_remove_device()
st: fix potential null pointer dereference.
scsi: report 'INQUIRY result too short' once per host
advansys: fix big-endian builds
qla2xxx: Fix rwlock recursion
hpsa: logical vs bitwise AND typo
mvsas: don't allow negative timeouts
mpt3sas: Fix use sas_is_tlr_enabled API before enabling MPI2_SCSIIO_CONTROL_TLR_ON flag
Pull drm fixes from Dave Airlie:
"A bunch of change across the board, the main things are some vblank
fallout in radeon and nouveau required some work, but I think this
should fix it all. There is also one drm fix for an oops in vmwgfx
with how we pass the drm master around.
The rest is just some amdgpu, i915, imx and rockchip fixes.
Probably more than I'd like at this point, but hopefully things settle
down now"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (40 commits)
drm/amdgpu: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v3)
drm/radeon: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v2)
drm/radeon: Retry DDC probing on DVI on failure if we got an HPD interrupt
drm/amdgpu: add spin lock to protect freed list in vm (v2)
drm/amdgpu: partially revert "drm/amdgpu: fix VM_CONTEXT*_PAGE_TABLE_END_ADDR" v2
drm/amdgpu: take a BO reference for the user fence
drm/amdgpu: take a BO reference in the display code
drm/amdgpu: set snooped flags only on system addresses v2
drm/nouveau: Fix pre-nv50 pageflip events (v4)
drm: Fix an unwanted master inheritance v2
drm/amdgpu: fix race condition in amd_sched_entity_push_job
drm/amdgpu: add err check for pin userptr
drm/i915: take a power domain reference while checking the HDMI live status
drm/i915: add MISSING_CASE to a few port/aux power domain helpers
drm/i915/ddi: fix intel_display_port_aux_power_domain() after HDMI detect
drm/i915: Introduce a gmbus power domain
drm/i915: Clean up AUX power domain handling
drm/rockchip: Use CRTC vblank event interface
drm/rockchip: Fix module autoload for OF platform driver
drm/rockchip: vop: fix window origin calculation
...
Pull crypto fixes from Herbert Xu:
"This fixes a couple of crypto drivers that were using memcmp to verify
authentication tags. They now use crypto_memneq instead"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: talitos - Fix timing leak in ESP ICV verification
crypto: nx - Fix timing leak in GCM and CCM decryption
When restarting a syscall with regs->ax == -ERESTART_RESTARTBLOCK,
regs->ax is assigned to a restart_syscall number. For x32 tasks, this
syscall number must have __X32_SYSCALL_BIT set, otherwise it will be
an x86_64 syscall number instead of a valid x32 syscall number. This
issue has been there since the introduction of x32.
Reported-by: strace/tests/restart_syscall.test
Reported-and-tested-by: Elvira Khabirova <lineprinter0@gmail.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Cc: Elvira Khabirova <lineprinter0@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20151130215436.GA25996@altlinux.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
MPX decodes instructions in order to tell which bounds register
was violated. Part of this decoding involves looking at the "REX
prefix" which is a special instrucion prefix used to retrofit
support for new registers in to old instructions.
The X86_REX_*() macros are defined to return actual bit values:
#define X86_REX_R(rex) ((rex) & 4)
*not* boolean values. However, the MPX code was checking for
them like they were booleans. This might have led to us
mis-decoding the "REX prefix" and giving false information out to
userspace about bounds violations. X86_REX_B() actually is bit 1,
so this is really only broken for the X86_REX_X() case.
Fix the conditionals up to tolerate the non-boolean values.
Fixes: fcc7ffd679 "x86, mpx: Decode MPX instruction to get bound violation information"
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: Dave Hansen <dave@sr71.net>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20151201003113.D800C1E0@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
A few more last minute fixes for 4.4 on top of my pull request from
earlier this week. The big change here is a vblank regression fix due to
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many vblanks
were missed". Beyond that, a hotplug fix and a few VM fixes.
* 'drm-fixes-4.4' of git://people.freedesktop.org/~agd5f/linux:
drm/amdgpu: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v3)
drm/radeon: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v2)
drm/radeon: Retry DDC probing on DVI on failure if we got an HPD interrupt
drm/amdgpu: add spin lock to protect freed list in vm (v2)
drm/amdgpu: partially revert "drm/amdgpu: fix VM_CONTEXT*_PAGE_TABLE_END_ADDR" v2
drm/amdgpu: take a BO reference for the user fence
drm/amdgpu: take a BO reference in the display code
drm/amdgpu: set snooped flags only on system addresses v2
drm/amdgpu: fix race condition in amd_sched_entity_push_job
drm/amdgpu: add err check for pin userptr
add blacklist for thinkpad T40p
drm/amdgpu: fix VM page table reference counting
drm/amdgpu: fix userptr flags check
Pull Ceph fix from Sage Weil:
"This addresses a refcounting bug that leads to a use-after-free"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
rbd: don't put snap_context twice in rbd_queue_workfn()
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many
vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core
more fragile to drivers which don't update hw vblank counters and
vblank timestamps in sync with firing of the vblank irq and
essentially at leading edge of vblank.
This exposed a problem with radeon-kms/amdgpu-kms which do not
satisfy above requirements:
The vblank irq fires a few scanlines before start of vblank, but
programmed pageflips complete at start of vblank and
vblank timestamps update at start of vblank, whereas the
hw vblank counter increments only later, at start of vsync.
This leads to problems like off by one errors for vblank counter
updates, vblank counters apparently going backwards or vblank
timestamps apparently having time going backwards. The net result
is stuttering of graphics in games, or little hangs, as well as
total failure of timing sensitive applications.
See bug #93147 for an example of the regression on Linux 4.4-rc:
https://bugs.freedesktop.org/show_bug.cgi?id=93147
This patch tries to align all above events better from the
viewpoint of the drm core / of external callers to fix the problem:
1. The apparent start of vblank is shifted a few scanlines earlier,
so the vblank irq now always happens after start of this extended
vblank interval and thereby drm_update_vblank_count() always samples
the updated vblank count and timestamp of the new vblank interval.
To achieve this, the reporting of scanout positions by
radeon_get_crtc_scanoutpos() now operates as if the vblank starts
radeon_crtc->lb_vblank_lead_lines before the real start of the hw
vblank interval. This means that the vblank timestamps which are based
on these scanout positions will now update at this earlier start of
vblank.
2. The driver->get_vblank_counter() function will bump the returned
vblank count as read from the hw by +1 if the query happens after
the shifted earlier start of the vblank, but before the real hw increment
at start of vsync, so the counter appears to increment at start of vblank
in sync with the timestamp update.
3. Calls from vblank irq-context and regular non-irq calls are now
treated identical, always simulating the shifted vblank start, to
avoid inconsistent results for queries happening from vblank irq vs.
happening from drm_vblank_enable() or vblank_disable_fn().
4. The radeon_flip_work_func will delay mmio programming a pageflip until
the start of the real vblank iff it happens to execute inside the shifted
earlier start of the vblank, so pageflips now also appear to execute at
start of the shifted vblank, in sync with vblank counter and timestamp
updates. This to avoid some races between updates of vblank count and
timestamps that are used for swap scheduling and pageflip execution which
could cause pageflips to execute before the scheduled target vblank.
The lb_vblank_lead_lines "fudge" value is calculated as the size of
the display controllers line buffer in scanlines for the given video
mode: Vblank irq's are triggered by the line buffer logic when the line
buffer refill for a video frame ends, ie. when the line buffer source read
position enters the hw vblank. This means that a vblank irq could fire at
most as many scanlines before the current reported scanout position of the
crtc timing generator as the number of scanlines the line buffer can
maximally hold for a given video mode.
This patch has been successfully tested on a RV730 card with DCE-3 display
engine and on a evergreen card with DCE-4 display engine, in single-display
and dual-display configuration, with different video modes.
A similar patch is needed for amdgpu-kms to fix the same problem.
Limitations:
- Maybe replace the udelay() in the flip_work_func() by a suitable
usleep_range() for a bit better efficiency? Will try that.
- Line buffer sizes in pixels are hard-coded on < DCE-4 to a value
i just guessed to be high enough to work ok, lacking info on the true
sizes atm.
Probably fixes: fdo#93147
Port of Mario's radeon fix to amdgpu.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
(v2) Refine amdgpu_flip_work_func() for better efficiency.
In amdgpu_flip_work_func, replace the busy waiting udelay(5)
with event lock held by a more performance and energy efficient
usleep_range() until at least predicted true start of hw vblank,
with some slack for scheduler happiness. Release the event lock
during waits to not delay other outputs in doing their stuff, as
the waiting can last up to 200 usecs in some cases.
Also small fix to code comment and formatting in that function.
(v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
(v3) Fix crash in crtc disabled case
Pull libnvdimm fixes from Dan Williams:
- NFIT parsing regression fixes from Linda. The nvdimm hot-add
implementation merged in 4.4-rc1 interpreted the specification in a
way that breaks actual HPE platforms. We are also closing the loop
with the ACPI Working Group to get this clarification added to the
spec.
- Andy pointed out that his laptop without nvdimm resources is loading
the e820-nvdimm module by default, fix that up to only load the
module when an e820-type-12 range is present.
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
nfit: Adjust for different _FIT and NFIT headers
nfit: Fix the check for a successful NFIT merge
nfit: Account for table size length variation
libnvdimm, e820: skip module loading when no type-12
- A series of fixes to deal with the aliasing between the sp and xzr register
- A fix for the cache flush fix that went in -rc3
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJWYc+rAAoJEL/70l94x66DlH4H/j7K4mDoruS8knO3WM7kZko5
McsWq17GQCpPoDEsciOFLe1hESgQG5e9Dp4aZPotivExovFFstfRGGXAfNC1E1kx
IskeJ6jxyYXtp6BDo5i9+lxCh3wSgO6IfphuXgiVJab8IdUxlDWkBPJrNPL7507l
UGNkCMBJ2v0gswMl4uJkFGpkC2vV13a8KmDCXKpLpElA6SoIFLIkBPfhu5JrORjz
Nn/Ky6wvc72AKDOpTbBPCE5Oz4+dRIiQdpjrXMqQA196DlgiDrGG/LcHm2/NxWI2
9Z8WepIc1FScPX8UCs9NzMkiydCv7oWL9ymHw5leVZj4rdd4bWV0Z9Ng1qRkU0Y=
=II4Q
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull ARM KVM fixes from Paolo Bonzini:
- a series of fixes to deal with the aliasing between the sp and xzr
register
- a fix for the cache flush fix that went in -rc3
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
ARM/arm64: KVM: correct PTE uncachedness check
arm64: KVM: Get rid of old vcpu_reg()
arm64: KVM: Correctly handle zero register in system register accesses
arm64: KVM: Remove const from struct sys_reg_params
arm64: KVM: Correctly handle zero register during MMIO
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many
vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core
more fragile to drivers which don't update hw vblank counters and
vblank timestamps in sync with firing of the vblank irq and
essentially at leading edge of vblank.
This exposed a problem with radeon-kms/amdgpu-kms which do not
satisfy above requirements:
The vblank irq fires a few scanlines before start of vblank, but
programmed pageflips complete at start of vblank and
vblank timestamps update at start of vblank, whereas the
hw vblank counter increments only later, at start of vsync.
This leads to problems like off by one errors for vblank counter
updates, vblank counters apparently going backwards or vblank
timestamps apparently having time going backwards. The net result
is stuttering of graphics in games, or little hangs, as well as
total failure of timing sensitive applications.
See bug #93147 for an example of the regression on Linux 4.4-rc:
https://bugs.freedesktop.org/show_bug.cgi?id=93147
This patch tries to align all above events better from the
viewpoint of the drm core / of external callers to fix the problem:
1. The apparent start of vblank is shifted a few scanlines earlier,
so the vblank irq now always happens after start of this extended
vblank interval and thereby drm_update_vblank_count() always samples
the updated vblank count and timestamp of the new vblank interval.
To achieve this, the reporting of scanout positions by
radeon_get_crtc_scanoutpos() now operates as if the vblank starts
radeon_crtc->lb_vblank_lead_lines before the real start of the hw
vblank interval. This means that the vblank timestamps which are based
on these scanout positions will now update at this earlier start of
vblank.
2. The driver->get_vblank_counter() function will bump the returned
vblank count as read from the hw by +1 if the query happens after
the shifted earlier start of the vblank, but before the real hw increment
at start of vsync, so the counter appears to increment at start of vblank
in sync with the timestamp update.
3. Calls from vblank irq-context and regular non-irq calls are now
treated identical, always simulating the shifted vblank start, to
avoid inconsistent results for queries happening from vblank irq vs.
happening from drm_vblank_enable() or vblank_disable_fn().
4. The radeon_flip_work_func will delay mmio programming a pageflip until
the start of the real vblank iff it happens to execute inside the shifted
earlier start of the vblank, so pageflips now also appear to execute at
start of the shifted vblank, in sync with vblank counter and timestamp
updates. This to avoid some races between updates of vblank count and
timestamps that are used for swap scheduling and pageflip execution which
could cause pageflips to execute before the scheduled target vblank.
The lb_vblank_lead_lines "fudge" value is calculated as the size of
the display controllers line buffer in scanlines for the given video
mode: Vblank irq's are triggered by the line buffer logic when the line
buffer refill for a video frame ends, ie. when the line buffer source read
position enters the hw vblank. This means that a vblank irq could fire at
most as many scanlines before the current reported scanout position of the
crtc timing generator as the number of scanlines the line buffer can
maximally hold for a given video mode.
This patch has been successfully tested on a RV730 card with DCE-3 display
engine and on a evergreen card with DCE-4 display engine, in single-display
and dual-display configuration, with different video modes.
A similar patch is needed for amdgpu-kms to fix the same problem.
Limitations:
- Line buffer sizes in pixels are hard-coded on < DCE-4 to a value
i just guessed to be high enough to work ok, lacking info on the true
sizes atm.
Fixes: fdo#93147
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Michel Dänzer <michel.daenzer@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
(v1) Tested-by: Dave Witbrodt <dawitbro@sbcglobal.net>
(v2) Refine radeon_flip_work_func() for better efficiency:
In radeon_flip_work_func, replace the busy waiting udelay(5)
with event lock held by a more performance and energy efficient
usleep_range() until at least predicted true start of hw vblank,
with some slack for scheduler happiness. Release the event lock
during waits to not delay other outputs in doing their stuff, as
the waiting can last up to 200 usecs in some cases.
Retested on DCE-3 and DCE-4 to verify it still works nicely.
(v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
HPD signals on DVI ports can be fired off before the pins required for
DDC probing actually make contact, due to the pins for HPD making
contact first. This results in a HPD signal being asserted but DDC
probing failing, resulting in hotplugging occasionally failing.
This is somewhat rare on most cards (depending on what angle you plug
the DVI connector in), but on some cards it happens constantly. The
Radeon R5 on the machine used for testing this patch for instance, runs
into this issue just about every time I try to hotplug a DVI monitor and
as a result hotplugging almost never works.
Rescheduling the hotplug work for a second when we run into an HPD
signal with a failing DDC probe usually gives enough time for the rest
of the connector's pins to make contact, and fixes this issue.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Lyude <cpaul@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
there is a protection fault about freed list when OCL test.
add a spin lock to protect it.
v2: drop changes in vm_fini
Signed-off-by: JimQu <jim.qu@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
The gtt_end is already inclusive, we don't need to subtract one here.
v2 (chk): keep the fix for the VM code, cause here it really applies.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Anatoli Antonovitch <anatoli.antonovitch@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
No need for a GEM reference here.
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
No need for the GEM reference here.
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
- A series of fixes to deal with the aliasing between the sp and xzr register
- A fix for the cache flush fix that went in -rc3
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=6wxm
-----END PGP SIGNATURE-----
Merge tag 'kvm-arm-for-v4.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master
KVM/ARM fixes for v4.4-rc4
- A series of fixes to deal with the aliasing between the sp and xzr register
- A fix for the cache flush fix that went in -rc3
Not necessary for VRAM.
v2: no need to check if ttm is NULL.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This time we've got a larger number of updates, mainly from ASoC
world. The only significant LOCs found here are for Realtek codecs,
where most of changes are quite systematic replacements.
There are also a few fixes in ASoC core side: one is the PM call order
fix to ensure the DPAM resume working properly. Another is the proper
cleanup call after freeing DAPM widgets, and the correction of the
wrong callback set in topology API.
The rest are a wide range of driver-specific small fixes, including
HD-audio.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=QKNa
-----END PGP SIGNATURE-----
Merge tag 'sound-4.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"This time we've got a larger number of updates, mainly from ASoC
world. The only significant LOCs found here are for Realtek codecs,
where most of changes are quite systematic replacements.
There are also a few fixes in ASoC core side: one is the PM call order
fix to ensure the DPAM resume working properly. Another is the proper
cleanup call after freeing DAPM widgets, and the correction of the
wrong callback set in topology API.
The rest are a wide range of driver-specific small fixes, including
HD-audio"
* tag 'sound-4.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (35 commits)
ALSA: hda - Add Conexant CX8200 (14f1:2008) codec entry
ALSA: hda - Correct codec names for 14f1:50f1 and 14f1:50f3
ALSA: hda - Skip ELD notification during system suspend
ASoC: core: Change power state before rechecking endpoint
ASoC: fix kernel-doc warnings in sound/soc/soc-ops.c
ASoC: rt5645: Add dmi_system_id "Google Terra"
ASoC: rockchip: Fix incorrect VDW value for 24 bit
ASoC: fsl: clarify ac97 dependency
ASoC: Intel: Skylake: fix memory leak
ASoC: davinci-mcasp: Fix master capture only mode
ASoC: es8328: Fix shifts for mixer switches
ASoC: rt5645: Add dmi_system_id "Google Wizpig"
ASoC: sti: set player private data
ASoC: sti: rename ST proprietary DT properties
ASoC: sti: remove wrong error message
ASoC: Intel: Skylake: Add I2C depends for SKL machine
ASoC: topology: fix info callback for TLV byte control
ASoC: rt5670: fix wrong bit def for pll src
ASoC: nau8825: add pm function
ASoC: rt5645: Add struct dmi_system_id "Google Edgar" for Chrome OS
...
- Fix a regression in the ACPI PCI host bridge initialization code
introduced by the recent consolidation of the host bridge handling
on x86 and ia64 that forgot to take one special piece of code
related to NUMA on x86 into account (Liu Jiang).
- Improve the Kconfig help description of the new ACPI AML debugger
support option to avoid possible confusion (Peter Zijlstra).
- Remove a piece of code in the generic power domains framework
that should have been removed by one of the recent commits
modifying that code (Ulf Hansson).
- Reduce the log level of a PCI PM message that generates a lot
of false-positive log noise for some drivers and improve the
message itself while at it (Imre Deak).
- Fix the OF-based domain lookup code in the generic power domains
framework to make it drop references to DT nodes correctly (Eric
Anholt).
- Prevent the cpufreq core from setting the policy back to the
default after a CPU offline/online cycle for cpufreq drivers
providing the ->setpolicy callback (Srinivas Pandruvada).
- Fix a build problem for CONFIG_ACPI unset in the device
properties framework (Hanjun Guo).
- Fix a stale file path in the ACPI backlight driver entry in
MAINTAINERS (Dan Carpenter).
/
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=HrEI
-----END PGP SIGNATURE-----
Merge tag 'pm+acpi-4.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management and ACPI fixes from Rafael Wysocki:
"These fix a recent regression in the ACPI PCI host bridge
initialization code, clean up some recent changes (generic power
domains framework, ACPI AML debugger support), fix three older but
annoying bugs (PCI power management. generic power domains framework,
cpufreq) and a build problem (device properties framework), and update
a stale MAINTAINERS entry (ACPI backlight driver).
Specifics:
- Fix a regression in the ACPI PCI host bridge initialization code
introduced by the recent consolidation of the host bridge handling
on x86 and ia64 that forgot to take one special piece of code
related to NUMA on x86 into account (Liu Jiang).
- Improve the Kconfig help description of the new ACPI AML debugger
support option to avoid possible confusion (Peter Zijlstra).
- Remove a piece of code in the generic power domains framework that
should have been removed by one of the recent commits modifying
that code (Ulf Hansson).
- Reduce the log level of a PCI PM message that generates a lot of
false-positive log noise for some drivers and improve the message
itself while at it (Imre Deak).
- Fix the OF-based domain lookup code in the generic power domains
framework to make it drop references to DT nodes correctly (Eric
Anholt).
- Prevent the cpufreq core from setting the policy back to the
default after a CPU offline/online cycle for cpufreq drivers
providing the ->setpolicy callback (Srinivas Pandruvada).
- Fix a build problem for CONFIG_ACPI unset in the device properties
framework (Hanjun Guo).
- Fix a stale file path in the ACPI backlight driver entry in
MAINTAINERS (Dan Carpenter)"
* tag 'pm+acpi-4.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / Domains: Fix bad of_node_put() in failure paths of genpd_dev_pm_attach()
cpufreq: use last policy after online for drivers with ->setpolicy
PCI / PM: Tune down retryable runtime suspend error messages
PM / Domains: Validate cases of a non-bound driver in genpd governor
MAINTAINERS: ACPI / video: update a file name in drivers/acpi/
ACPI / property: fix compile error for acpi_node_get_property_reference() when CONFIG_ACPI=n
x86/PCI/ACPI: Fix regression caused by commit 4d6b4e69a2
ACPI: Better describe ACPI_DEBUGGER
Commit e6fab54423 ("ARM/arm64: KVM: test properly for a PTE's
uncachedness") modified the logic to test whether a HYP or stage-2
mapping needs flushing, from [incorrectly] interpreting the page table
attributes to [incorrectly] checking whether the PFN that backs the
mapping is covered by host system RAM. The PFN number is part of the
output of the translation, not the input, so we have to use pte_pfn()
on the contents of the PTE, not __phys_to_pfn() on the HYP virtual
address or stage-2 intermediate physical address.
Fixes: e6fab54423 ("ARM/arm64: KVM: test properly for a PTE's uncachedness")
Cc: stable@vger.kernel.org
Tested-by: Pavel Fedin <p.fedin@samsung.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Using oldstyle vcpu_reg() accessor is proven to be inappropriate and
unsafe on ARM64. This patch converts the rest of use cases to new
accessors and completely removes vcpu_reg() on ARM64.
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
System register accesses also use zero register for Rt == 31, and
therefore using it will also result in getting SP value instead. This
patch makes them also using new accessors, introduced by the previous
patch. Since register value is no longer directly associated with storage
inside vCPU context structure, we introduce a dedicated storage for it in
struct sys_reg_params.
This refactor also gets rid of "massive hack" in kvm_handle_cp_64().
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Further rework is going to introduce a dedicated storage for transfer
register value in struct sys_reg_params. Before doing this we have to
remove 'const' modifiers from it in all accessor functions and their
callers.
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
On ARM64 register index of 31 corresponds to both zero register and SP.
However, all memory access instructions, use ZR as transfer register. SP
is used only as a base register in indirect memory addressing, or by
register-register arithmetics, which cannot be trapped here.
Correct emulation is achieved by introducing new register accessor
functions, which can do special handling for reg_num == 31. These new
accessors intentionally do not rely on old vcpu_reg() on ARM64, because
it is to be removed. Since the affected code is shared by both ARM
flavours, implementations of these accessors are also added to ARM32 code.
This patch fixes setting MMIO register to a random value (actually SP)
instead of zero by something like:
*((volatile int *)reg) = 0;
compilers tend to generate "str wzr, [xx]" here
[Marc: Fixed 32bit splat]
Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Commit 4e752f0ab0 ("rbd: access snapshot context and mapping size
safely") moved ceph_get_snap_context() out of rbd_img_request_create()
and into rbd_queue_workfn(), adding a ceph_put_snap_context() to the
error path in rbd_queue_workfn(). However, rbd_img_request_create()
consumes a ref on snapc, so calling ceph_put_snap_context() after
a successful rbd_img_request_create() leads to an extra put. Fix it.
Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Josh Durgin <jdurgin@redhat.com>
* pm-domains:
PM / Domains: Fix bad of_node_put() in failure paths of genpd_dev_pm_attach()
PM / Domains: Validate cases of a non-bound driver in genpd governor
* pm-cpufreq:
cpufreq: use last policy after online for drivers with ->setpolicy
Oleg noticed that its possible to falsely observe p->on_cpu == 0 such
that we'll prematurely continue with the wakeup and effectively run p on
two CPUs at the same time.
Even though the overlap is very limited; the task is in the middle of
being scheduled out; it could still result in corruption of the
scheduler data structures.
CPU0 CPU1
set_current_state(...)
<preempt_schedule>
context_switch(X, Y)
prepare_lock_switch(Y)
Y->on_cpu = 1;
finish_lock_switch(X)
store_release(X->on_cpu, 0);
try_to_wake_up(X)
LOCK(p->pi_lock);
t = X->on_cpu; // 0
context_switch(Y, X)
prepare_lock_switch(X)
X->on_cpu = 1;
finish_lock_switch(Y)
store_release(Y->on_cpu, 0);
</preempt_schedule>
schedule();
deactivate_task(X);
X->on_rq = 0;
if (X->on_rq) // false
if (t) while (X->on_cpu)
cpu_relax();
context_switch(X, ..)
finish_lock_switch(X)
store_release(X->on_cpu, 0);
Avoid the load of X->on_cpu being hoisted over the X->on_rq load.
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Explain how the control dependency and smp_rmb() end up providing
ACQUIRE semantics and pair with smp_store_release() in
finish_lock_switch().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
/proc/stats shows invalid gtime when the thread is running in guest.
When vtime accounting is not enabled, we cannot get a valid delta.
The delta is calculated with now - tsk->vtime_snap, but tsk->vtime_snap
is only updated when vtime accounting is runtime enabled.
This patch makes task_gtime() just return gtime without computing the
buggy non-existing tickless delta when vtime accounting is not enabled.
Use context_tracking_is_enabled() to check if vtime is accounting on
some cpu, in which case only we need to check the tickless delta. This
way we fix the gtime value regression on machines not running nohz full.
The kernel config contains CONFIG_VIRT_CPU_ACCOUNTING_GEN=y and
CONFIG_NO_HZ_FULL_ALL=n and boot without nohz_full.
I ran and stop a busy loop in VM and see the gtime in host.
Dump the 43rd field which shows the gtime in every second:
# while :; do awk '{print $3" "$43}' /proc/3955/task/4014/stat; sleep 1; done
S 4348
R 7064566
R 7064766
R 7064967
R 7065168
S 4759
S 4759
During running busy loop, it returns large value.
After applying this patch, we can see right gtime.
# while :; do awk '{print $3" "$43}' /proc/10913/task/10956/stat; sleep 1; done
S 5338
R 5365
R 5465
R 5566
R 5666
S 5726
S 5726
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1447948054-28668-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
root_domain::rto_mask allocated through alloc_cpumask_var()
contains garbage data, this may cause problems. For instance,
When doing pull_rt_task(), it may do useless iterations if
rto_mask retains some extra garbage bits. Worse still, this
violates the isolated domain rule for clustered scheduling
using cpuset, because the tasks(with all the cpus allowed)
belongs to one root domain can be pulled away into another
root domain.
The patch cleans the garbage by using zalloc_cpumask_var()
instead of alloc_cpumask_var() for root_domain::rto_mask
allocation, thereby addressing the issues.
Do the same thing for root_domain's other cpumask memembers:
dlo_mask, span, and online.
Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1449057179-29321-1-git-send-email-xlpang@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Because wakeups can (fundamentally) be late, a task might not be in
the expected state. Therefore testing against a task's state is racy,
and can yield false positives.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: oleg@redhat.com
Fixes: 9067ac85d5 ("wake_up_process() should be never used to wakeup a TASK_STOPPED/TRACED task")
Link: http://lkml.kernel.org/r/1448933660-23082-1-git-send-email-sasha.levin@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Venkatesh Srinivas