Servers may send a callback array that is the same size as
the FID array, or an empty array. If the callback count is
0, the code would attempt to read (fid_count * 12) bytes of
data, which would fail and result in an unmarshalling error.
This would lead to stale data for remotely modified files
or directories.
Store the callback array size in the internal afs_call
structure and use that to determine the amount of data to
read.
Signed-off-by: Marc Dionne <[email protected]>
Mode bits for an afs file should not be enforced in the usual
way.
For files, the absence of user bits can restrict file access
with respect to what is granted by the server.
These bits apply regardless of the owner or the current uid; the
rest of the mode bits (group, other) are ignored.
Signed-off-by: Marc Dionne <[email protected]>
Signed-off-by: David Howells <[email protected]>
The group was hard coded to GLOBAL_ROOT_GID; use the group
ID that was received from the server.
Signed-off-by: Marc Dionne <[email protected]>
Signed-off-by: David Howells <[email protected]>
afs_fill_page() loads the page it wants to fill into the afs_read request
without incrementing its refcount - but then calls afs_put_read() to clean
up afterwards, which then releases a ref on the page.
Fix this by getting a ref on the page before calling
afs_vnode_fetch_data().
This causes sync after a write to hang in afs_writepages_region() because
find_get_pages_tag() gets confused and doesn't return.
Fixes: 196ee9cd2d ("afs: Make afs_fs_fetch_data() take a list of pages")
Reported-by: Marc Dionne <[email protected]>
Signed-off-by: David Howells <[email protected]>
Tested-by: Marc Dionne <[email protected]>
In afs_writepages_region(), inside the loop where we find dirty pages to
deal with, one of the if-statements is missing a put_page().
Signed-off-by: David Howells <[email protected]>
GVTg has introduced the context status notifier to schedule the GVTg
workload. At that time, the notifier is bound to GVTg context only,
so GVTg is not aware of host workloads.
Now we are going to improve GVTg's guest workload scheduler policy,
and add Guc emulation support for new Gen graphics. Both these two
features require acknowledgment for all contexts running on hardware.
(But will not alter host workload.) So here try to make some change.
The change is simple:
1. Move the context status notifier head from i915_gem_context to
intel_engine_cs. Which means there is a notifier head per engine
instead of per context. Execlist driver still call notifier for
each context sched-in/out events of current engine.
2. At GVTg side, it binds a notifier_block for each physical engine
at GVTg initialization period. Then GVTg can hear all context
status events.
In this patch, GVTg do nothing for host context event, but later
will add a function there. But in any case, the notifier callback is
a noop if this is no active vGPU.
Since intel_gvt_init() is called at early initialization stage and
require the status notifier head has been initiated, I initiate it in
intel_engine_setup().
v2: remove a redundant newline. (chris)
Fixes: 3c7ba6359d ("drm/i915: Introduce execlist context status change notification")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100232
Signed-off-by: Changbin Du <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Cc: Zhi Wang <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
Acked-by: Zhenyu Wang <[email protected]>
Signed-off-by: Chris Wilson <[email protected]>
This emulates execlists on top of the GuC in order to defer submission of
requests to the hardware. This deferral allows time for high priority
requests to gazump their way to the head of the queue, however it nerfs
the GuC by converting it back into a simple execlist (where the CPU has
to wake up after every request to feed new commands into the GuC).
v2: Drop hack status - though iirc there is still a lockdep inversion
between fence and engine->timeline->lock (which is impossible as the
nesting only occurs on different fences - hopefully just requires some
judicious lockdep annotation)
v3: Apply lockdep nesting to enabling signaling on the request, using
the pattern we already have in __i915_gem_request_submit();
v4: Replaying requests after a hang also now needs the timeline
spinlock, to disable the interrupts at least
v5: Hold wq lock for completeness, and emit a tracepoint for enabling signal
v6: Reorder interrupt checking for a happier gcc.
v7: Only signal the tasklet after a user-interrupt if using guc scheduling
v8: Restore lost update of rq through the i915_guc_irq_handler (Tvrtko)
v9: Avoid re-initialising the engine->irq_tasklet from inside a reset
v10: Hook up the execlists-style tracepoints
v11: Clear the execlists irq_posted bit after taking over the interrupt/tasklet
Signed-off-by: Chris Wilson <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Reviewed-by: Tvrtko Ursulin <[email protected]>
Reviewed-by: Joonas Lahtinen <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
Reviewed-by: Michał Winiarski <[email protected]>
While going through the event inheritance code Oleg got confused.
Add some comments to better explain the silent dissapearance of
orphaned events.
So what happens is that at perf_event_release_kernel() time; when an
event looses its connection to userspace (and ceases to exist from the
user's perspective) we can still have an arbitrary amount of inherited
copies of the event. We want to synchronously find and remove all
these child events.
Since that requires a bit of lock juggling, there is the possibility
that concurrent clone()s will create new child events. Therefore we
first mark the parent event as DEAD, which marks all the extant child
events as orphaned.
We then avoid copying orphaned events; in order to avoid getting more
of them.
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Dmitry Vyukov <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
We have used cz timestamp register to gain a reference time wrt
to residency calculations. The residency counts are in cz clk ticks
(333Mhz clock) but for some reason the cz timestamp register gives
100us units. Perhaps for some other usage, the base-ten based values
are easier, but in residency calculations raw units would have been
the easiest.
As there is not much advantage of using base-ten clock through
a more costly punit access, take our reference times directly from
kernel clock.
v2: use ktime (Chris, Ville)
Cc: Chris Wilson <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Signed-off-by: Mika Kuoppala <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Use intel_rc6_residency to get benefit for increased resolution
in byt/chv.
v2: output raw and time (Chris)
Signed-off-by: Mika Kuoppala <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Vlv and chv residency counters are 40 bits in width.
With a control bit, we can choose between upper or lower
32 bit window into this counter.
Lets toggle this bit on and off on and read both parts.
As a result we can push the wrap from 13 seconds to 54
minutes.
v2: commit msg, loop readability, goto elimination (Chris)
v3: bug ref, divide outside runtime pm lock (Chris)
References: https://bugs.freedesktop.org/show_bug.cgi?id=94852
Reported-by: Len Brown <[email protected]>
Cc: Chris Wilson <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Signed-off-by: Mika Kuoppala <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Change the granularity from milliseconds to microseconds
when returning rc6 residencies. This is in preparation
for increased resolution on some platforms.
v2: use 64bit div macro (Chris)
Cc: Chris Wilson <[email protected]>
Signed-off-by: Mika Kuoppala <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Plan is to make generic residency calculation utility
function for usage outside of sysfs. As a first step
move residency calculation into intel_pm.c
Signed-off-by: Mika Kuoppala <[email protected]>
Reviewed-by: Chris Wilson <[email protected]>
Test runs on a ppc64 BE guest succeeded. linux/samples/statx/test-statx
program was executed on the following file types,
1. Regular file
2. Directory
3. device file
4. symlink
5. Named pipe
The test run also included invoking test-statx with the runtime options
provided in the main() function of test-statx.c
Signed-off-by: Chandan Rajendra <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
No one is using the structure imx_drm_component, so let's remove the
definition to save several lines.
Signed-off-by: Liu Ying <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
Allow the planes to use the PRG/PRE units as linear prefetchers when
possible. This improves DRAM efficiency a bit and reduces the chance
for display underflow when the memory subsystem is under load.
This does not yet support scanning out tiled buffers directly, as this
needs more work, but it already wires up the basic interaction between
imx-drm, the IPUv3 driver and the PRG and PRE drivers.
Signed-off-by: Lucas Stach <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
On i.MX6 QuadPlus the PRG needs to be clocked in order to pass
through the data access requests from the IDMAC. This call is a
no-op for other all other SoCs.
Signed-off-by: Lucas Stach <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
Using non-zero AXI IDs for anything other than the display channels
collides with the PRG AXI snooping, so only do this if there is no
PRG present.
Signed-off-by: Lucas Stach <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
The i.MX6 QuadPlus IPU needs to PRG unit to gain access to the
data bus. Make sure it is present and available to be used.
Signed-off-by: Lucas Stach <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
Document the valid compatible strings for the IPUv3.
On i.MX6 QuadPlus the IPU needs to know which PRG has to be
used for this IPU instance. Add a "fsl,prg" property containing
a phandle pointing to the correct PRG device.
Signed-off-by: Lucas Stach <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
This adds support for the i.MX6 QUadPlus PRG unit. It glues together the
IPU and the PRE units.
Signed-off-by: Lucas Stach <[email protected]>
Signed-off-by: Philipp Zabel <[email protected]>
---
v4: add missing ipu_soc->prg_priv
On vblank instant-off systems, we can get into a situation where the cost
of enabling and disabling the vblank IRQ around a drmWaitVblank query
dominates. And with the advent of even deeper hardware sleep state,
touching registers becomes ever more expensive. However, we know that if
the user wants the current vblank counter, they are also very likely to
immediately queue a vblank wait and so we can keep the interrupt around
and only turn it off if we have no further vblank requests queued within
the interrupt interval.
After vblank event delivery, this patch adds a shadow of one vblank where
the interrupt is kept alive for the user to query and queue another vblank
event. Similarly, if the user is using blocking drmWaitVblanks, the
interrupt will be disabled on the IRQ following the wait completion.
However, if the user is simply querying the current vblank counter and
timestamp, the interrupt will be disabled after every IRQ and the user
will enabled it again on the first query following the IRQ.
v2: Mario Kleiner -
After testing this, one more thing that would make sense is to move
the disable block at the end of drm_handle_vblank() instead of at the
top.
Turns out that if high precision timestaming is disabled or doesn't
work for some reason (as can be simulated by echo 0 >
/sys/module/drm/parameters/timestamp_precision_usec), then with your
delayed disable code at its current place, the vblank counter won't
increment anymore at all for instant queries, ie. with your other
"instant query" patches. Clients which repeatedly query the counter
and wait for it to progress will simply hang, spinning in an endless
query loop. There's that comment in vblank_disable_and_save:
"* Skip this step if there isn't any high precision timestamp
* available. In that case we can't account for this and just
* hope for the best.
*/
With the disable happening after leading edge of vblank (== hw counter
increment already happened) but before the vblank counter/timestamp
handling in drm_handle_vblank, that step is needed to keep the counter
progressing, so skipping it is bad.
Now without high precision timestamping support, a kms driver must not
set dev->vblank_disable_immediate = true, as this would cause problems
for clients, so this shouldn't matter, but it would be good to still
make this robust against a future kms driver which might have
unreliable high precision timestamping, e.g., high precision
timestamping that intermittently doesn't work.
v3: Patch before coffee needs extra coffee.
Testcase: igt/kms_vblank
Signed-off-by: Chris Wilson <[email protected]>
Cc: Ville Syrjälä <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Michel Dänzer <[email protected]>
Cc: Laurent Pinchart <[email protected]>
Cc: Dave Airlie <[email protected]>,
Cc: Mario Kleiner <[email protected]>
Reviewed-by: Ville Syrjälä <[email protected]>
Signed-off-by: Daniel Vetter <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
I was testing Daniel's changes with his test case, and tweaked it a
little. Instead of having the runtime equal to the deadline, I
increased the deadline ten fold.
Daniel's test case had:
attr.sched_runtime = 2 * 1000 * 1000; /* 2 ms */
attr.sched_deadline = 2 * 1000 * 1000; /* 2 ms */
attr.sched_period = 2 * 1000 * 1000 * 1000; /* 2 s */
To make it more interesting, I changed it to:
attr.sched_runtime = 2 * 1000 * 1000; /* 2 ms */
attr.sched_deadline = 20 * 1000 * 1000; /* 20 ms */
attr.sched_period = 2 * 1000 * 1000 * 1000; /* 2 s */
The results were rather surprising. The behavior that Daniel's patch
was fixing came back. The task started using much more than .1% of the
CPU. More like 20%.
Looking into this I found that it was due to the dl_entity_overflow()
constantly returning true. That's because it uses the relative period
against relative runtime vs the absolute deadline against absolute
runtime.
runtime / (deadline - t) > dl_runtime / dl_period
There's even a comment mentioning this, and saying that when relative
deadline equals relative period, that the equation is the same as using
deadline instead of period. That comment is backwards! What we really
want is:
runtime / (deadline - t) > dl_runtime / dl_deadline
We care about if the runtime can make its deadline, not its period. And
then we can say "when the deadline equals the period, the equation is
the same as using dl_period instead of dl_deadline".
After correcting this, now when the task gets enqueued, it can throttle
correctly, and Daniel's fix to the throttling of sleeping deadline
tasks works even when the runtime and deadline are not the same.
Signed-off-by: Steven Rostedt (VMware) <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Daniel Bristot de Oliveira <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Luca Abeni <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Romulo Silva de Oliveira <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tommaso Cucinotta <[email protected]>
Link: http://lkml.kernel.org/r/02135a27f1ae3fe5fd032568a5a2f370e190e8d7.1488392936.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <[email protected]>
During the activation, CBS checks if it can reuse the current task's
runtime and period. If the deadline of the task is in the past, CBS
cannot use the runtime, and so it replenishes the task. This rule
works fine for implicit deadline tasks (deadline == period), and the
CBS was designed for implicit deadline tasks. However, a task with
constrained deadline (deadine < period) might be awakened after the
deadline, but before the next period. In this case, replenishing the
task would allow it to run for runtime / deadline. As in this case
deadline < period, CBS enables a task to run for more than the
runtime / period. In a very loaded system, this can cause a domino
effect, making other tasks miss their deadlines.
To avoid this problem, in the activation of a constrained deadline
task after the deadline but before the next period, throttle the
task and set the replenishing timer to the begin of the next period,
unless it is boosted.
Reproducer:
--------------- %< ---------------
int main (int argc, char **argv)
{
int ret;
int flags = 0;
unsigned long l = 0;
struct timespec ts;
struct sched_attr attr;
memset(&attr, 0, sizeof(attr));
attr.size = sizeof(attr);
attr.sched_policy = SCHED_DEADLINE;
attr.sched_runtime = 2 * 1000 * 1000; /* 2 ms */
attr.sched_deadline = 2 * 1000 * 1000; /* 2 ms */
attr.sched_period = 2 * 1000 * 1000 * 1000; /* 2 s */
ts.tv_sec = 0;
ts.tv_nsec = 2000 * 1000; /* 2 ms */
ret = sched_setattr(0, &attr, flags);
if (ret < 0) {
perror("sched_setattr");
exit(-1);
}
for(;;) {
/* XXX: you may need to adjust the loop */
for (l = 0; l < 150000; l++);
/*
* The ideia is to go to sleep right before the deadline
* and then wake up before the next period to receive
* a new replenishment.
*/
nanosleep(&ts, NULL);
}
exit(0);
}
--------------- >% ---------------
On my box, this reproducer uses almost 50% of the CPU time, which is
obviously wrong for a task with 2/2000 reservation.
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Luca Abeni <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Romulo Silva de Oliveira <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tommaso Cucinotta <[email protected]>
Link: http://lkml.kernel.org/r/edf58354e01db46bf42df8d2dd32418833f68c89.1488392936.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <[email protected]>
Currently, the replenishment timer is set to fire at the deadline
of a task. Although that works for implicit deadline tasks because the
deadline is equals to the begin of the next period, that is not correct
for constrained deadline tasks (deadline < period).
For instance:
f.c:
--------------- %< ---------------
int main (void)
{
for(;;);
}
--------------- >% ---------------
# gcc -o f f.c
# trace-cmd record -e sched:sched_switch \
-e syscalls:sys_exit_sched_setattr \
chrt -d --sched-runtime 490000000 \
--sched-deadline 500000000 \
--sched-period 1000000000 0 ./f
# trace-cmd report | grep "{pid of ./f}"
After setting parameters, the task is replenished and continue running
until being throttled:
f-11295 [003] 13322.113776: sys_exit_sched_setattr: 0x0
The task is throttled after running 492318 ms, as expected:
f-11295 [003] 13322.606094: sched_switch: f:11295 [-1] R ==> watchdog/3:32 [0]
But then, the task is replenished 500719 ms after the first
replenishment:
<idle>-0 [003] 13322.614495: sched_switch: swapper/3:0 [120] R ==> f:11295 [-1]
Running for 490277 ms:
f-11295 [003] 13323.104772: sched_switch: f:11295 [-1] R ==> swapper/3:0 [120]
Hence, in the first period, the task runs 2 * runtime, and that is a bug.
During the first replenishment, the next deadline is set one period away.
So the runtime / period starts to be respected. However, as the second
replenishment took place in the wrong instant, the next replenishment
will also be held in a wrong instant of time. Rather than occurring in
the nth period away from the first activation, it is taking place
in the (nth period - relative deadline).
Signed-off-by: Daniel Bristot de Oliveira <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Luca Abeni <[email protected]>
Reviewed-by: Steven Rostedt (VMware) <[email protected]>
Reviewed-by: Juri Lelli <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Romulo Silva de Oliveira <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Tommaso Cucinotta <[email protected]>
Link: http://lkml.kernel.org/r/ac50d89887c25285b47465638354b63362f8adff.1488392936.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <[email protected]>
We hang if SIGKILL has been sent, but the task is stuck in down_read()
(after do_exit()), even though no task is doing down_write() on the
rwsem in question:
INFO: task libupnp:21868 blocked for more than 120 seconds.
libupnp D 0 21868 1 0x08100008
...
Call Trace:
__schedule()
schedule()
__down_read()
do_exit()
do_group_exit()
__wake_up_parent()
This bug has already been fixed for CONFIG_RWSEM_XCHGADD_ALGORITHM=y in
the following commit:
04cafed7fc ("locking/rwsem: Fix down_write_killable()")
... however, this bug also exists for CONFIG_RWSEM_GENERIC_SPINLOCK=y.
Signed-off-by: Niklas Cassel <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: <[email protected]>
Cc: <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Niklas Cassel <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Fixes: d47996082f ("locking/rwsem: Introduce basis for down_write_killable()")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
'calc_load_update' is accessed without any kind of locking and there's
a clear assumption in the code that only a single value is read or
written.
Make this explicit by using READ_ONCE() and WRITE_ONCE(), and avoid
unintentionally seeing multiple values, or having the load/stores
split.
Technically the loads in calc_global_*() don't require this since
those are the only functions that update 'calc_load_update', but I've
added the READ_ONCE() for consistency.
Suggested-by: Peter Zijlstra <[email protected]>
Signed-off-by: Matt Fleming <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Morten Rasmussen <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vincent Guittot <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
If we crossed a sample window while in NO_HZ we will add LOAD_FREQ to
the pending sample window time on exit, setting the next update not
one window into the future, but two.
This situation on exiting NO_HZ is described by:
this_rq->calc_load_update < jiffies < calc_load_update
In this scenario, what we should be doing is:
this_rq->calc_load_update = calc_load_update [ next window ]
But what we actually do is:
this_rq->calc_load_update = calc_load_update + LOAD_FREQ [ next+1 window ]
This has the effect of delaying load average updates for potentially
up to ~9seconds.
This can result in huge spikes in the load average values due to
per-cpu uninterruptible task counts being out of sync when accumulated
across all CPUs.
It's safe to update the per-cpu active count if we wake between sample
windows because any load that we left in 'calc_load_idle' will have
been zero'd when the idle load was folded in calc_global_load().
This issue is easy to reproduce before,
commit 9d89c257df ("sched/fair: Rewrite runnable load and utilization average tracking")
just by forking short-lived process pipelines built from ps(1) and
grep(1) in a loop. I'm unable to reproduce the spikes after that
commit, but the bug still seems to be present from code review.
Signed-off-by: Matt Fleming <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Morten Rasmussen <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vincent Guittot <[email protected]>
Fixes: commit 5167e8d ("sched/nohz: Rewrite and fix load-avg computation -- again")
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
The following warning can be triggered by hot-unplugging the CPU
on which an active SCHED_DEADLINE task is running on:
------------[ cut here ]------------
WARNING: CPU: 7 PID: 0 at kernel/sched/sched.h:833 replenish_dl_entity+0x71e/0xc40
rq->clock_update_flags < RQCF_ACT_SKIP
CPU: 7 PID: 0 Comm: swapper/7 Tainted: G B 4.11.0-rc1+ #24
Hardware name: LENOVO ThinkCentre M8500t-N000/SHARKBAY, BIOS FBKTC1AUS 02/16/2016
Call Trace:
<IRQ>
dump_stack+0x85/0xc4
__warn+0x172/0x1b0
warn_slowpath_fmt+0xb4/0xf0
? __warn+0x1b0/0x1b0
? debug_check_no_locks_freed+0x2c0/0x2c0
? cpudl_set+0x3d/0x2b0
replenish_dl_entity+0x71e/0xc40
enqueue_task_dl+0x2ea/0x12e0
? dl_task_timer+0x777/0x990
? __hrtimer_run_queues+0x270/0xa50
dl_task_timer+0x316/0x990
? enqueue_task_dl+0x12e0/0x12e0
? enqueue_task_dl+0x12e0/0x12e0
__hrtimer_run_queues+0x270/0xa50
? hrtimer_cancel+0x20/0x20
? hrtimer_interrupt+0x119/0x600
hrtimer_interrupt+0x19c/0x600
? trace_hardirqs_off+0xd/0x10
local_apic_timer_interrupt+0x74/0xe0
smp_apic_timer_interrupt+0x76/0xa0
apic_timer_interrupt+0x93/0xa0
The DL task will be migrated to a suitable later deadline rq once the DL
timer fires and currnet rq is offline. The rq clock of the new rq should
be updated. This patch fixes it by updating the rq clock after holding
the new rq's rq lock.
Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Matt Fleming <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
A few amd fixes.
* 'drm-fixes-4.11' of git://people.freedesktop.org/~agd5f/linux:
drm/amd/amdgpu: Fix debugfs reg read/write address width
drm/amdgpu/si: add dpm quirk for Oland
drm/radeon/si: add dpm quirk for Oland
drm: amd: remove broken include path
drm/amd/powerplay: fix copy error in smu7_clockpoweragting.c
drm/amdgpu: fix parser init error path to avoid crash in parser fini
drm/amd/amdgpu: Disable GFX_PG on Carrizo until compute issues solved
Pull block fixes from Jens Axboe:
"Four small fixes for this cycle:
- followup fix from Neil for a fix that went in before -rc2, ensuring
that we always see the full per-task bio_list.
- fix for blk-mq-sched from me that ensures that we retain similar
direct-to-issue behavior on running the queue.
- fix from Sagi fixing a potential NULL pointer dereference in blk-mq
on spurious CPU unplug.
- a memory leak fix in writeback from Tahsin, fixing a case where
device removal of a mounted device can leak a struct
wb_writeback_work"
* 'for-linus' of git://git.kernel.dk/linux-block:
blk-mq-sched: don't run the queue async from blk_mq_try_issue_directly()
writeback: fix memory leak in wb_queue_work()
blk-mq: Fix tagset reinit in the presence of cpu hot-unplug
blk: Ensure users for current->bio_list can see the full list.
There is a missing newline in show_cpuinfo_cur_freq(), so add it,
but while at it clean that function up somewhat too.
Signed-off-by: Rafael J. Wysocki <[email protected]>
Acked-by: Viresh Kumar <[email protected]>
Cc: All applicable <[email protected]>
Check that request has not been signaled before acquiring a reference to
the request for signaling later in the interrupt handler.
The loading of the cacheline (for request->fence.flags) should be "free"
when followed by the locked increment of the request->fence.refcount
(which then sets the cacheline to exclusive mode), i.e. the cost of
test_bit prior to an atomic_inc should be negligible. This should
benefit us when we have a pile of bare breadcrumbs (interrupted execbuf)
where we may get interrupts faster than we can get rid of the
intel_wait, or if the device is too slow to run the bottom-half between
interrupts.
Signed-off-by: Chris Wilson <[email protected]>
Cc: Mika Kuoppala <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Reviewed-by: Tvrtko Ursulin <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
We need to ensure that we always serialize updates to the bottom-half
using the breadcrumbs.irq_lock so that we don't race with a concurrent
interrupt handler. This is most important just prior to leaving the
waiter (when the intel_wait will be overwritten), so make sure we are
not the current bottom-half when skipping the irq locks.
Signed-off-by: Chris Wilson <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Reviewed-by: Tvrtko Ursulin <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
Before walking the rbtree of waiters (marking them as complete and waking
them), decouple the interrupt handler. This prevents a race between the
missed waiter waking up and removing its intel_wait (which skips
checking the lock) and the interrupt handler dereferencing the
intel_wait. (Though we do not expect to encounter waiters during idle!)
Fixes: e1c0c91bda ("drm/i915: Wake up all waiters before idling")
Signed-off-by: Chris Wilson <[email protected]>
Cc: Mika Kuoppala <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Reviewed-by: Tvrtko Ursulin <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
When adding a new request to the breadcrumb rbtree, we mark all those
requests inside the rbtree that are already completed as complete. This
wakes those waiters up and allows them to skip the spinlock before
returning to userspace. If one of those is the current bottom-half and
allocated its intel_wait on the stack, it may then overwrite the
b->irq_wait upon exiting i915_wait_request() just as the interrupt handler
dereferences it.
Fixes: 56299fb7d9 ("drm/i915: Signal first fence from irq handler if complete")
Signed-off-by: Chris Wilson <[email protected]>
Cc: Tvrtko Ursulin <[email protected]>
Cc: Mika Kuoppala <[email protected]>
Reviewed-by: Tvrtko Ursulin <[email protected]>
Link: http://patchwork.freedesktop.org/patch/msgid/[email protected]
Commit 09b871ffd4 (parisc: Define access_ok() as macro) missed to mark uaddr
as used, which then gives compiler warnings about unused variables.
Fix it by comparing uaddr to uaddr which then gets optimized away by the
compiler.
Signed-off-by: Helge Deller <[email protected]>
Fixes: 09b871ffd4 ("parisc: Define access_ok() as macro")
