Our global struct with params is named exactly the same way
as new preferred name for the drm_i915_private function parameter.
To avoid such name reuse lets use different name for the global.

v5: pure rename
v6: fix

Credits-to: Coccinelle

@@
identifier n;
@@
(
-	i915.n
+	i915_modparams.n
)
Signed-off-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Ville Syrjala <ville.syrjala@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170919193846.38060-1-michal.wajdeczko@intel.com

Since we make call i915_gem_context_mark_guilty() concurrently when
resetting different engines in parallel, we need to make sure that our
updates are safe for the unlocked access.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170721123238.16428-12-chris@chris-wilson.co.ukSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Driver maintains count of how many times a given engine is reset, useful to
capture this in error state also. It gives an idea of how engine is coping
up with the workloads it is executing before this error state.

A follow-up patch will provide this information in debugfs.

v2: s/engine_reset/reset_engine/ (Chris)
    Define count as unsigned int (Tvrtko)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170615201828.23144-7-michel.thierry@intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170620095751.13127-7-chris@chris-wilson.co.uk

add/remove: 1/1 grow/shrink: 5/4 up/down: 391/-578 (-187)
function                                     old     new   delta
execlists_submit_ports                       262     471    +209
port_assign.isra                               -     136    +136
capture                                     6344    6359     +15
reset_common_ring                            438     452     +14
execlists_submit_request                     228     238     +10
gen8_init_common_ring                        334     341      +7
intel_engine_is_idle                         106     105      -1
i915_engine_info                            2314    2290     -24
__i915_gem_set_wedged_BKL                    485     411     -74
intel_lrc_irq_handler                       1789    1604    -185
execlists_update_context                     294       -    -294

The most important change there is the improve to the
intel_lrc_irq_handler and excclist_submit_ports (net improvement since
execlists_update_context is now inlined).

v2: Use the port_api() for guc as well (even though currently we do not
pack any counters in there, yet) and hide all port->request_count inside
the helpers.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170517121007.27224-5-chris@chris-wilson.co.uk

CCID register existed already on ILK according to the PRM (Chris
verified the address to match too).
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1493366019-18380-1-git-send-email-joonas.lahtinen@linux.intel.com

HAS_HW_CONTEXTS is misleading condition for GPU reset and CCID,
replace it with Gen specific (to be updated in next patches).

HAS_HW_CONTEXTS in i915_l3_write is bogus because each HAS_L3_DPF
match also has .has_hw_contexts = 1 set.

This leads to us being able to get rid of the property completely.

v2:
- Keep the checks at Gen6 for no functional change (Ville)
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>

Introduce a new execobject.flag (EXEC_OBJECT_CAPTURE) that userspace may
use to indicate that it wants the contents of this buffer preserved in
the error state (/sys/class/drm/cardN/error) following a GPU hang
involving this batch.

Use this at your discretion, the contents of the error state. although
compressed, are allocated with GFP_ATOMIC (i.e. limited) and kept for all
eternity (until the error state is destroyed).

Based on an earlier patch by Ben Widawsky <ben@bwidawsk.net>
Testcase: igt/gem_exec_capture
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Matt Turner <mattst88@gmail.com>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Acked-by: NMatt Turner <mattst88@gmail.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170415093902.22581-1-chris@chris-wilson.co.uk

As we now take the breadcrumbs spinlock within the interrupt handler, we
wish to minimise its hold time. During the interrupt we do not care
about the state of the full rbtree, only that of the first element, so
we can guard that with a separate lock.

v2: Rename first_wait to irq_wait to make it clearer that it is guarded
by irq_lock.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303190824.1330-1-chris@chris-wilson.co.uk

Useful for double checking that the device is powered up when it hung,
include both the status of the power management and our rpm wakelock.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302151544.16915-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>

Whilst investigating some mysterious failures with hangcheck not running
during gem_busy/basic-hang-default, the question is why did we decide to
cancel the retire_work (which queues the hangcheck)? That decision is
based around GT activity, so include that information in the debug
report.

v2: Include the GT awake status in the error state
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302150356.9713-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>

Handling the dynamic charp module parameter requires us to copy it for
the error state, or remember to lock it when reading (in case it used
with 0600).

v2: Use __always_inline and __builtin_strcmp
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170221162619.15954-1-chris@chris-wilson.co.ukReviewed-by: NJani Nikula <jani.nikula@intel.com>

Once upon a time before we had automated GPU state capture upon hangs,
we had intel_gpu_dump. Now we come almost full circle and reinstate that
view of the current GPU queues and registers by using the error capture
facility to snapshot the GPU state when debugfs/.../i915_gpu_info is
opened - which should provided useful debugging to both the error
capture routines (without having to cause a hang and avoid the error
state being eaten by igt) and generally.

v2: Rename drm_i915_error_state to i915_gpu_state to alleviate some name
collisions between the error state dump and inspecting the gpu state.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170214164611.11381-1-chris@chris-wilson.co.uk

They include useful material such as what mode the VM address space is
running in, what submission mode, extra quirks, etc.

v2: Undef the right macro, use type specific pretty printers
v3: Use strcmp(TYPENAME) rather than creating per-type pretty printers
v4: Use __always_inline to force GCC to eliminate the calls to strcmp and
generate the right call to seq_printf for each parameter.
v5: With the strcmp elimination, we can now use BUILD_BUG to ensure
there are no unhandled types, also use __builtin_strcmp to make it look
even more magic.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: NMika Kuoppala <mika.kuoppala@intel.com>
Acked-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170206213608.31328-3-chris@chris-wilson.co.uk

Include extra information such as the user_handle and hw_id so that
userspace can identify which of their contexts hung, useful if they are
performing self-diagnositics.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170129092433.10483-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>

To make the code clearer, use rb_entry() instead of container_of() to
deal with rbtree.
Signed-off-by: NGeliang Tang <geliangtang@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/b08fd4be9d4c45d88c158a17b854c3fd628840ed.1484816339.git.geliangtang@gmail.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/i915_gpu_error.c: In function ‘i915_error_vprintf’:
drivers/gpu/drm/i915/i915_gpu_error.c:137:3: warning:
function might be possible candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format]
   len = vsnprintf(NULL, 0, f, tmp);
   ^~~
drivers/gpu/drm/i915/i915_gpu_error.c:144:2: warning:
function might be possible candidate for ‘gnu_printf’ format attribute [-Wsuggest-attribute=format]
  len = vsnprintf(e->buf + e->bytes, e->size - e->bytes, f, args);
  ^~~
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170114105113.1231-1-chris@chris-wilson.co.ukReviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>

In order to silence sparse:

../drivers/gpu/drm/i915/i915_gpu_error.c:200:39: warning: Using plain integer as NULL pointer

add a helper to check whether we have sse4.1 and that the desired
alignment is valid for acceleration.

v2: Explain the macros and split the two use cases between
i915_has_memcpy_from_wc() and i915_can_memcpy_from_wc().
Reported-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170106152013.24684-1-chris@chris-wilson.co.uk

The existing kerneldoc was outdated, so time for a refresh.

v2: Use single line kdoc, mention functions for manipulation
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161231112012.29263-3-chris@chris-wilson.co.uk

The platform flags in device info are (mostly) mutually
exclusive. Replace the flags with an enum. Add the platform enum also
for platforms that previously didn't have a flag, and give them codename
logging in dmesg.

Pineview remains an exception, the platform being G33 for that.

v2: Sort enum by gen and date

v3: rebase on geminilake enabling
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480596595-3278-1-git-send-email-jani.nikula@intel.com

On all platforms we now always read the contents of buffers via the GTT,
i.e. using WC cpu access. Reads are slow, but they can be accelerated
with an internal read buffer using sse4.1 (movntqda). This is our
i915_memcpy_from_wc() routine which also checks for sse4.1 support and
so we can fallback to using a regular slow memcpy if we need to.

When compressing the pages, the reads are currently done inside zlib's
fill_window() routine and so we must copy the page into a temporary
which is then already inside the CPU cache and fast for zlib's
compression. When not compressing the pages, we don't need a temporary
and can just use the accelerated read from WC into the destination.

v2: Use zstream locals to reduce diff and allocate the additional
temporary storage only if sse4.1 is supported.
v3: Use length=0 for the sse4.1 support check
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161206124051.17040-1-chris@chris-wilson.co.ukReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>

Since it does not need dev at all.

Also change the stored pointer in struct i915_error_state_file_priv
to i915.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>

Bannable property, banned status, guilty and active counts are
properties of i915_gem_context. Make them so.

v2: rebase

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479309634-28574-1-git-send-email-mika.kuoppala@intel.com

If we have a bad client submitting unfavourably across different
contexts, creating new ones, the per context scoring of badness
doesn't remove the root cause, the offending client.
To counter, keep track of per client context bans. Deny access if
client is responsible for more than 3 context bans in
it's lifetime.

v2: move ban check to context create ioctl (Chris)
v3: add commentary about hangs needed to reach client ban (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>

Now when driver has per context scoring of 'hanging badness'
and also subsequent hangs during short windows are allowed,
if there is progress made in between, it does not make sense
to expose a ban timing window as a context parameter anymore.

Let the scoring be the sole indicator for ban policy and substitute
ban period context parameter as a boolean to get/set context
bannable property.

v2: allow non root to opt into being banned (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>

Hangcheck state accumulation has gained more steps
along the years, like head movement and more recently the
subunit inactivity check. As the subunit sampling is only
done if the previous state check showed inactivity, we
have added more stages (and time) to reach a hang verdict.

Asymmetric engine states led to different actual weight of
'one hangcheck unit' and it was demonstrated in some
hangs that due to difference in stages, simpler engines
were accused falsely of a hang as their scoring was much
more quicker to accumulate above the hang treshold.

To completely decouple the hangcheck guilty score
from the hangcheck period, convert hangcheck score to a
rough period of inactivity measurement. As these are
tracked as jiffies, they are meaningful also across
reset boundaries. This makes finding a guilty engine
more accurate across multi engine activity scenarios,
especially across asymmetric engines.

We lose the ability to detect cross batch malicious attempts
to hinder the progress. Plan is to move this functionality
to be part of context banning which is more natural fit,
later in the series.

v2: use time_before macros (Chris)
    reinstate the pardoning of moving engine after hc (Chris)
v3: avoid global state for per engine stall detection (Chris)
v4: take timeline last retirement into account (Chris)
v5: do debug print on pardoning, split out retirement timestamp (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>

In order to simplify hangcheck state keeping, split hangcheck
per engine loop in three phases: state load, action, state save.

Add few more hangcheck actions to separate between seqno, head
and subunit movements. This helps to gather all the hangcheck
actions under a single switch umbrella.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>

I tried to avoid having to track the write for every VMA by only
tracking writes to the ggtt. However, for the purposes of frontbuffer
tracking this is insufficient as we need to invalidate around writes not
just to the the ggtt but all aliased ppgtt views of the framebuffer. By
moving the critical section to the object and only doing so for
framebuffer writes we can reduce the tracking even further by only
watching framebuffers and not vma.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161116190704.5293-1-chris@chris-wilson.co.ukTested-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>

And a little bit of cascaded function prototype changes.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

A small selection of macros which can only accept dev_priv from
now on and a resulting trickle of fixups.

v2: Keep original order. (Ville Syrjala)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDavid Weinehall <david.weinehall@linux.intel.com>

A small selection of macros which can only accept dev_priv from
now on and a resulting trickle of fixups.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDavid Weinehall <david.weinehall@linux.intel.com>

Get rid of sloppy inline functions now that we don't have more users:

i915_gem_request_get_seqno
i915_gem_request_get_engine

v2:
- request->engine is always non-NULL (Chris)
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1478589108-3702-1-git-send-email-joonas.lahtinen@linux.intel.com

Whilst waiting on a request, we may do so without holding any locks or
any guards beyond a reference to the request. In order to avoid taking
locks within request deallocation, we drop references to its timeline
(via the context and ppgtt) upon retirement. We should avoid chasing
such pointers outside of their control, in particular we inspect the
request->timeline to see if we may restore the RPS waitboost for a
client. If we instead look at the engine->timeline, we will have similar
behaviour on both full-ppgtt and !full-ppgtt systems and reduce the
amount of reward we give towards stalling clients (i.e. only if the
client stalls and the GPU is uncontended does it reclaim its boost).
This restores behaviour back to pre-timelines, whilst fixing:

[  645.078485] BUG: KASAN: use-after-free in i915_gem_object_wait_fence+0x1ee/0x2e0 at addr ffff8802335643a0
[  645.078577] Read of size 4 by task gem_exec_schedu/28408
[  645.078638] CPU: 1 PID: 28408 Comm: gem_exec_schedu Not tainted 4.9.0-rc2+ #64
[  645.078724] Hardware name:                  /        , BIOS PYBSWCEL.86A.0027.2015.0507.1758 05/07/2015
[  645.078816]  ffff88022daef9a0 ffffffff8143d059 ffff880235402a80 ffff880233564200
[  645.078998]  ffff88022daef9c8 ffffffff81229c5c ffff88022daefa48 ffff880233564200
[  645.079172]  ffff880235402a80 ffff88022daefa38 ffffffff81229ef0 000000008110a796
[  645.079345] Call Trace:
[  645.079404]  [<ffffffff8143d059>] dump_stack+0x68/0x9f
[  645.079467]  [<ffffffff81229c5c>] kasan_object_err+0x1c/0x70
[  645.079534]  [<ffffffff81229ef0>] kasan_report_error+0x1f0/0x4b0
[  645.079601]  [<ffffffff8122a244>] kasan_report+0x34/0x40
[  645.079676]  [<ffffffff81634f5e>] ? i915_gem_object_wait_fence+0x1ee/0x2e0
[  645.079741]  [<ffffffff81229951>] __asan_load4+0x61/0x80
[  645.079807]  [<ffffffff81634f5e>] i915_gem_object_wait_fence+0x1ee/0x2e0
[  645.079876]  [<ffffffff816364bf>] i915_gem_object_wait+0x19f/0x590
[  645.079944]  [<ffffffff81636320>] ? i915_gem_object_wait_priority+0x500/0x500
[  645.080016]  [<ffffffff8110fb30>] ? debug_show_all_locks+0x1e0/0x1e0
[  645.080084]  [<ffffffff8110abdc>] ? check_chain_key+0x14c/0x210
[  645.080157]  [<ffffffff8110a796>] ? __lock_is_held+0x46/0xc0
[  645.080226]  [<ffffffff8163bc61>] ? i915_gem_set_domain_ioctl+0x141/0x690
[  645.080296]  [<ffffffff8163bcc2>] i915_gem_set_domain_ioctl+0x1a2/0x690
[  645.080366]  [<ffffffff811f8f85>] ? __might_fault+0x75/0xe0
[  645.080433]  [<ffffffff815a55f7>] drm_ioctl+0x327/0x640
[  645.080508]  [<ffffffff8163bb20>] ? i915_gem_obj_prepare_shmem_write+0x3a0/0x3a0
[  645.080603]  [<ffffffff815a52d0>] ? drm_ioctl_permit+0x120/0x120
[  645.080670]  [<ffffffff8110abdc>] ? check_chain_key+0x14c/0x210
[  645.080738]  [<ffffffff81275717>] do_vfs_ioctl+0x127/0xa20
[  645.080804]  [<ffffffff8120268c>] ? do_mmap+0x47c/0x580
[  645.080871]  [<ffffffff811da567>] ? vm_mmap_pgoff+0x117/0x140
[  645.080938]  [<ffffffff812755f0>] ? ioctl_preallocate+0x150/0x150
[  645.081011]  [<ffffffff81108c53>] ? up_write+0x23/0x50
[  645.081078]  [<ffffffff811da567>] ? vm_mmap_pgoff+0x117/0x140
[  645.081145]  [<ffffffff811da450>] ? vma_is_stack_for_current+0x90/0x90
[  645.081214]  [<ffffffff8110d853>] ? mark_held_locks+0x23/0xc0
[  645.082030]  [<ffffffff81288408>] ? __fget+0x168/0x250
[  645.082106]  [<ffffffff819ad517>] ? entry_SYSCALL_64_fastpath+0x5/0xb1
[  645.082176]  [<ffffffff81288592>] ? __fget_light+0xa2/0xc0
[  645.082242]  [<ffffffff8127604c>] SyS_ioctl+0x3c/0x70
[  645.082309]  [<ffffffff819ad52e>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  645.082374] Object at ffff880233564200, in cache kmalloc-8192 size: 8192
[  645.082431] Allocated:
[  645.082480] PID = 28408
[  645.082535]  [  645.082566] [<ffffffff8103ae66>] save_stack_trace+0x16/0x20
[  645.082623]  [  645.082656] [<ffffffff81228b06>] save_stack+0x46/0xd0
[  645.082716]  [  645.082756] [<ffffffff812292fd>] kasan_kmalloc+0xad/0xe0
[  645.082817]  [  645.082848] [<ffffffff81631752>] i915_ppgtt_create+0x52/0x220
[  645.082908]  [  645.082941] [<ffffffff8161db96>] i915_gem_create_context+0x396/0x560
[  645.083027]  [  645.083059] [<ffffffff8161f857>] i915_gem_context_create_ioctl+0x97/0xf0
[  645.083152]  [  645.083183] [<ffffffff815a55f7>] drm_ioctl+0x327/0x640
[  645.083243]  [  645.083274] [<ffffffff81275717>] do_vfs_ioctl+0x127/0xa20
[  645.083334]  [  645.083372] [<ffffffff8127604c>] SyS_ioctl+0x3c/0x70
[  645.083432]  [  645.083464] [<ffffffff819ad52e>] entry_SYSCALL_64_fastpath+0x1c/0xb1
[  645.083551] Freed:
[  645.083599] PID = 27629
[  645.083648]  [  645.083676] [<ffffffff8103ae66>] save_stack_trace+0x16/0x20
[  645.083738]  [  645.083770] [<ffffffff81228b06>] save_stack+0x46/0xd0
[  645.083830]  [  645.083862] [<ffffffff81229203>] kasan_slab_free+0x73/0xc0
[  645.083922]  [  645.083961] [<ffffffff812279c9>] kfree+0xa9/0x170
[  645.084021]  [  645.084053] [<ffffffff81629f60>] i915_ppgtt_release+0x100/0x180
[  645.084139]  [  645.084171] [<ffffffff8161d414>] i915_gem_context_free+0x1b4/0x230
[  645.084257]  [  645.084288] [<ffffffff816537b2>] intel_lr_context_unpin+0x192/0x230
[  645.084380]  [  645.084413] [<ffffffff81645250>] i915_gem_request_retire+0x620/0x630
[  645.084500]  [  645.085226] [<ffffffff816473d1>] i915_gem_retire_requests+0x181/0x280
[  645.085313]  [  645.085352] [<ffffffff816352ba>] i915_gem_retire_work_handler+0xca/0xe0
[  645.085440]  [  645.085471] [<ffffffff810c725b>] process_one_work+0x4fb/0x920
[  645.085532]  [  645.085562] [<ffffffff810c770d>] worker_thread+0x8d/0x840
[  645.085622]  [  645.085653] [<ffffffff810d21e5>] kthread+0x185/0x1b0
[  645.085718]  [  645.085750] [<ffffffff819ad7a7>] ret_from_fork+0x27/0x40
[  645.085811] Memory state around the buggy address:
[  645.085869]  ffff880233564280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  645.085956]  ffff880233564300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  645.086053] >ffff880233564380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  645.086138]                                ^
[  645.086193]  ffff880233564400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[  645.086283]  ffff880233564480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

v2: Add a comment to document the hint like nature of
 intel_engine_last_submit()

Fixes: 73cb9701 ("drm/i915: Combine seqno + tracking into a global timeline struct")
Fixes: 80b204bc ("drm/i915: Enable multiple timelines")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161101100317.11129-1-chris@chris-wilson.co.uk

The breadcrumbs are about to be used from within IRQ context sections
(e.g. nouveau signals a fence from an interrupt handler causing us to
submit a new request) and/or from bottom-half tasklets (i.e.
intel_lrc_irq_handler), therefore we need to employ the irqsafe spinlock
variants.

For example, deferring the request submission to the
intel_lrc_irq_handler generates this trace:

[   66.388639] =================================
[   66.388650] [ INFO: inconsistent lock state ]
[   66.388663] 4.9.0-rc2+ #56 Not tainted
[   66.388672] ---------------------------------
[   66.388682] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   66.388695] swapper/1/0 [HC0[0]:SC1[1]:HE0:SE0] takes:
[   66.388706]  (&(&b->lock)->rlock){+.?...} , at: [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.388761] {SOFTIRQ-ON-W} state was registered at:
[   66.388772]   [   66.388783] [<ffffffff810bd842>] __lock_acquire+0x682/0x1870
[   66.388795]   [   66.388803] [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.388814]   [   66.388824] [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.388835]   [   66.388845] [<ffffffff81401e41>] intel_engine_reset_breadcrumbs+0x21/0xb0
[   66.388857]   [   66.388866] [<ffffffff81403ae7>] gen8_init_common_ring+0x67/0x100
[   66.388878]   [   66.388887] [<ffffffff81403b92>] gen8_init_render_ring+0x12/0x60
[   66.388903]   [   66.388912] [<ffffffff813f8707>] i915_gem_init_hw+0xf7/0x2a0
[   66.388927]   [   66.388936] [<ffffffff813f899b>] i915_gem_init+0xbb/0xf0
[   66.388950]   [   66.388959] [<ffffffff813b4980>] i915_driver_load+0x7e0/0x1330
[   66.388978]   [   66.388988] [<ffffffff813c09d8>] i915_pci_probe+0x28/0x40
[   66.389003]   [   66.389013] [<ffffffff812fa0db>] pci_device_probe+0x8b/0xf0
[   66.389028]   [   66.389037] [<ffffffff8147737e>] driver_probe_device+0x21e/0x430
[   66.389056]   [   66.389065] [<ffffffff8147766e>] __driver_attach+0xde/0xe0
[   66.389080]   [   66.389090] [<ffffffff814751ad>] bus_for_each_dev+0x5d/0x90
[   66.389105]   [   66.389113] [<ffffffff81477799>] driver_attach+0x19/0x20
[   66.389134]   [   66.389144] [<ffffffff81475ced>] bus_add_driver+0x15d/0x260
[   66.389159]   [   66.389168] [<ffffffff81477e3b>] driver_register+0x5b/0xd0
[   66.389183]   [   66.389281] [<ffffffff812fa19b>] __pci_register_driver+0x5b/0x60
[   66.389301]   [   66.389312] [<ffffffff81aed333>] i915_init+0x3e/0x45
[   66.389326]   [   66.389336] [<ffffffff81ac2ffa>] do_one_initcall+0x8b/0x118
[   66.389350]   [   66.389359] [<ffffffff81ac323a>] kernel_init_freeable+0x1b3/0x23b
[   66.389378]   [   66.389387] [<ffffffff8160fc39>] kernel_init+0x9/0x100
[   66.389402]   [   66.389411] [<ffffffff816180e7>] ret_from_fork+0x27/0x40
[   66.389426] irq event stamp: 315865
[   66.389438] hardirqs last  enabled at (315864): [<ffffffff816178f1>] _raw_spin_unlock_irqrestore+0x31/0x50
[   66.389469] hardirqs last disabled at (315865): [<ffffffff816176b3>] _raw_spin_lock_irqsave+0x13/0x50
[   66.389499] softirqs last  enabled at (315818): [<ffffffff8107a04c>] _local_bh_enable+0x1c/0x50
[   66.389530] softirqs last disabled at (315819): [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.389559]
[   66.389559] other info that might help us debug this:
[   66.389580]  Possible unsafe locking scenario:
[   66.389580]
[   66.389598]        CPU0
[   66.389609]        ----
[   66.389620]   lock(&(&b->lock)->rlock);
[   66.389650]   <Interrupt>
[   66.389661]     lock(&(&b->lock)->rlock);
[   66.389690]
[   66.389690]  *** DEADLOCK ***
[   66.389690]
[   66.389715] 2 locks held by swapper/1/0:
[   66.389728]  #0: (&(&tl->lock)->rlock){..-...}, at: [<ffffffff81403e01>] intel_lrc_irq_handler+0x201/0x3c0
[   66.389785]  #1: (&(&req->lock)->rlock/1){..-...}, at: [<ffffffff813fc0af>] __i915_gem_request_submit+0x8f/0x170
[   66.389854]
[   66.389854] stack backtrace:
[   66.389959] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.9.0-rc2+ #56
[   66.389976] Hardware name:                  /        , BIOS PYBSWCEL.86A.0027.2015.0507.1758 05/07/2015
[   66.389999]  ffff88027fd03c58 ffffffff812beae5 ffff88027696e680 ffffffff822afe20
[   66.390036]  ffff88027fd03ca8 ffffffff810bb420 0000000000000001 0000000000000000
[   66.390070]  0000000000000000 0000000000000006 0000000000000004 ffff88027696ee10
[   66.390104] Call Trace:
[   66.390117]  <IRQ>
[   66.390128]  [<ffffffff812beae5>] dump_stack+0x68/0x93
[   66.390147]  [<ffffffff810bb420>] print_usage_bug+0x1d0/0x1e0
[   66.390164]  [<ffffffff810bb8a0>] mark_lock+0x470/0x4f0
[   66.390181]  [<ffffffff810ba9d0>] ? print_shortest_lock_dependencies+0x1b0/0x1b0
[   66.390203]  [<ffffffff810bd75d>] __lock_acquire+0x59d/0x1870
[   66.390221]  [<ffffffff810bedbc>] lock_acquire+0x6c/0xb0
[   66.390237]  [<ffffffff810bedbc>] ? lock_acquire+0x6c/0xb0
[   66.390255]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390273]  [<ffffffff8161753a>] _raw_spin_lock+0x2a/0x40
[   66.390291]  [<ffffffff81401c88>] ? intel_engine_enable_signaling+0x78/0x150
[   66.390309]  [<ffffffff81401c88>] intel_engine_enable_signaling+0x78/0x150
[   66.390327]  [<ffffffff813fc170>] __i915_gem_request_submit+0x150/0x170
[   66.390345]  [<ffffffff81403e8b>] intel_lrc_irq_handler+0x28b/0x3c0
[   66.390363]  [<ffffffff81079d97>] tasklet_action+0x57/0xc0
[   66.390380]  [<ffffffff8107a249>] __do_softirq+0x119/0x240
[   66.390396]  [<ffffffff8107a50e>] irq_exit+0xbe/0xd0
[   66.390414]  [<ffffffff8101afd5>] do_IRQ+0x65/0x110
[   66.390431]  [<ffffffff81618806>] common_interrupt+0x86/0x86
[   66.390446]  <EOI>
[   66.390457]  [<ffffffff814ec6d1>] ? cpuidle_enter_state+0x151/0x200
[   66.390480]  [<ffffffff814ec7a2>] cpuidle_enter+0x12/0x20
[   66.390498]  [<ffffffff810b639e>] call_cpuidle+0x1e/0x40
[   66.390516]  [<ffffffff810b65ae>] cpu_startup_entry+0x10e/0x1f0
[   66.390534]  [<ffffffff81036133>] start_secondary+0x103/0x130

(This is split out of the defer global seqno allocation patch due to
realisation that we need a more complete conversion if we want to defer
request submission even further.)

v2: lockdep was warning about mixed SOFTIRQ contexts not HARDIRQ
contexts so we only need to use spin_lock_bh and not disable interrupts.

v3: We need full irq protection as we may be called from a third party
interrupt handler (via fences).
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-32-chris@chris-wilson.co.uk

Currently we try to reduce the number of synchronisations (now the
number of requests we need to wait upon) by noting that if we have
earlier waited upon a request, all subsequent requests in the timeline
will be after the wait. This only applies to requests in this timeline,
as other timelines will not be ordered by that waiter.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-30-chris@chris-wilson.co.uk

Though we will have multiple timelines, we still have a single timeline
of execution. This we can use to provide an execution and retirement order
of requests. This keeps tracking execution of requests simple, and vital
for preserving a single waiter (i.e. so that we can order the waiters so
that only the earliest to wakeup need be woken). To accomplish this we
distinguish the seqno used to order requests per-context (external) and
that used internally for execution.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-26-chris@chris-wilson.co.uk

Our timelines are more than just a seqno. They also provide an ordered
list of requests to be executed. Due to the restriction of handling
individual address spaces, we are limited to a timeline per address
space but we use a fence context per engine within.

Our first step to introducing independent timelines per context (i.e. to
allow each context to have a queue of requests to execute that have a
defined set of dependencies on other requests) is to provide a timeline
abstraction for the global execution queue.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-23-chris@chris-wilson.co.uk

In preparation to support many distinct timelines, we need to expand the
activity tracking on the GEM object to handle more than just a request
per engine. We already use the struct reservation_object on the dma-buf
to handle many fence contexts, so integrating that into the GEM object
itself is the preferred solution. (For example, we can now share the same
reservation_object between every consumer/producer using this buffer and
skip the manual import/export via dma-buf.)

v2: Reimplement busy-ioctl (by walking the reservation object), postpone
the ABI change for another day. Similarly use the reservation object to
find the last_write request (if active and from i915) for choosing
display CS flips.

Caveats:

 * busy-ioctl: busy-ioctl only reports on the native fences, it will not
warn of stalls (in set-domain-ioctl, pread/pwrite etc) if the object is
being rendered to by external fences. It also will not report the same
busy state as wait-ioctl (or polling on the dma-buf) in the same
circumstances. On the plus side, it does retain reporting of which
*i915* engines are engaged with this object.

 * non-blocking atomic modesets take a step backwards as the wait for
render completion blocks the ioctl. This is fixed in a subsequent
patch to use a fence instead for awaiting on the rendering, see
"drm/i915: Restore nonblocking awaits for modesetting"

 * dynamic array manipulation for shared-fences in reservation is slower
than the previous lockless static assignment (e.g. gem_exec_lut_handle
runtime on ivb goes from 42s to 66s), mainly due to atomic operations
(maintaining the fence refcounts).

 * loss of object-level retirement callbacks, emulated by VMA retirement
tracking.

 * minor loss of object-level last activity information from debugfs,
could be replaced with per-vma information if desired
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-21-chris@chris-wilson.co.uk

The plan is to make obtaining the backing storage for the object avoid
struct_mutex (i.e. use its own locking). The first step is to update the
API so that normal users only call pin/unpin whilst working on the
backing storage.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161028125858.23563-12-chris@chris-wilson.co.uk

As well as knowing when the error occurred, it is more interesting to me
to know how long after booting the error occurred, and for good measure
record the time since last hw initialisation.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMatthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161025121602.1457-1-chris@chris-wilson.co.uk

Added the dump of GuC log buffer to i915 error state, as the contents of
GuC log buffer would also be useful to determine that why the GPU reset
was triggered.

v2:
- For uniformity use existing helper function print_error_obj() to
  dump out contents of GuC log buffer, pretty printing is better left
  to userspace. (Chris)
- Skip the dumping of GuC log buffer when logging is disabled as it
  won't be of any use.
- Rebase.

v3: Rebase.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NAkash Goel <akash.goel@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>