Our existing behaviour is to allow contexts and their GPU requests to
persist past the point of closure until the requests are complete. This
allows clients to operate in a 'fire-and-forget' manner where they can
setup a rendering pipeline and hand it over to the display server and
immediately exit. As the rendering pipeline is kept alive until
completion, the display server (or other consumer) can use the results
in the future and present them to the user.
The compute model is a little different. They have little to no buffer
sharing between processes as their kernels tend to operate on a
continuous stream, feeding the results back to the client application.
These kernels operate for an indeterminate length of time, with many
clients wishing that the kernel was always running for as long as they
keep feeding in the data, i.e. acting like a DSP.
Not all clients want this persistent "desktop" behaviour and would prefer
that the contexts are cleaned up immediately upon closure. This ensures
that when clients are run without hangchecking (e.g. for compute kernels
of indeterminate runtime), any GPU hang or other unexpected workloads
are terminated with the process and does not continue to hog resources.
The default behaviour for new contexts is the legacy persistence mode,
as some desktop applications are dependent upon the existing behaviour.
New clients will have to opt in to immediate cleanup on context
closure. If the hangchecking modparam is disabled, so is persistent
context support -- all contexts will be terminated on closure.
We expect this behaviour change to be welcomed by compute users, who
have often been caught between a rock and a hard place. They disable
hangchecking to avoid their kernels being "unfairly" declared hung, but
have also experienced true hangs that the system was then unable to
clean up. Naturally, this leads to bug reports.
Testcase: igt/gem_ctx_persistence
Link: https://github.com/intel/compute-runtime/pull/228
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: Jon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20191029202338.8841-1-chris@chris-wilson.co.uk
Normally, we rely on our hangcheck to prevent persistent batches from
hogging the GPU. However, if the user disables hangcheck, this mechanism
breaks down. Despite our insistence that this is unsafe, the users are
equally insistent that they want to use endless batches and will disable
the hangcheck mechanism. We are looking at replacing hangcheck, in the
next patch, with a softer mechanism, that sends a pulse down the engine
to check if it is well. We can use the same preemptive pulse to flush an
active context off the GPU upon context close, preventing resources
being lost and unkillable requests remaining on the GPU after process
termination.
Testcase: igt/gem_ctx_exec/basic-nohangcheck
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: Jon Bloomfield <jon.bloomfield@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191023133108.21401-4-chris@chris-wilson.co.uk
Medium term goal is to eliminate the i915->engine[] array and to get there
we have recently introduced equivalent array in intel_gt. Now we need to
migrate the code further towards this state.
This next step is to eliminate usage of i915->engines[] from the
for_each_engine_masked iterator.
For this to work we also need to use engine->id as index when populating
the gt->engine[] array and adjust the default engine set indexing to use
engine->legacy_idx instead of assuming gt->engines[] indexing.
v2:
* Populate gt->engine[] earlier.
* Check that we don't duplicate engine->legacy_idx
v3:
* Work around the initialization order issue between default_engines()
and intel_engines_driver_register() which sets engine->legacy_idx for
now. It will be fixed properly later.
v4:
* Merge with forgotten v2.5.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191017161852.8836-1-tvrtko.ursulin@linux.intel.com
We would like to make use of perf in Vulkan. The Vulkan API is much
lower level than OpenGL, with applications directly exposed to the
concept of command buffers (pretty much equivalent to our batch
buffers). In Vulkan, queries are always limited in scope to a command
buffer. In OpenGL, the lack of command buffer concept meant that
queries' duration could span multiple command buffers.
With that restriction gone in Vulkan, we would like to simplify
measuring performance just by measuring the deltas between the counter
snapshots written by 2 MI_RECORD_PERF_COUNT commands, rather than the
more complex scheme we currently have in the GL driver, using 2
MI_RECORD_PERF_COUNT commands and doing some post processing on the
stream of OA reports, coming from the global OA buffer, to remove any
unrelated deltas in between the 2 MI_RECORD_PERF_COUNT.
Disabling preemption only apply to a single context with which want to
query performance counters for and is considered a privileged
operation, by default protected by CAP_SYS_ADMIN. It is possible to
enable it for a normal user by disabling the paranoid stream setting.
v2: Store preemption setting in intel_context (Chris)
v3: Use priorities to avoid preemption rather than the HW mechanism
v4: Just modify the port priority reporting function
v5: Add nopreempt flag on gem context and always flag requests
appropriately, regarless of OA reconfiguration.
Link: https://gitlab.freedesktop.org/mesa/mesa/merge_requests/932
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191014201404.22468-4-chris@chris-wilson.co.uk
drm-misc-next for 5.5:
UAPI Changes:
-Colorspace: Expose different prop values for DP vs. HDMI (Gwan-gyeong Mun)
-fourcc: Add DRM_FORMAT_MOD_ARM_16X16_BLOCK_U_INTERLEAVED (Raymond)
-not_actually: s/ENOTSUPP/EOPNOTSUPP/ in drm_edid and drm_mipi_dbi. This should
not reach userspace, but adding here to specifically call that out (Daniel)
-i810: Prevent underflow in dispatch ioctls (Dan)
-komeda: Add ACLK sysfs attribute (Mihail)
-v3d: Allow userspace to clean up after render jobs (Iago)
Cross-subsystem Changes:
-MAINTAINERS:
-Add Alyssa & Steven as panfrost reviewers (Rob)
-Add Jernej as DE2 reviewer (Maxime)
-Add Chen-Yu as Allwinner maintainer (Maxime)
-staging: Make some stack arrays static const (Colin)
Core Changes:
-ttm: Allow drivers to specify their vma manager (to use gem mgr) (Gerd)
-docs: Various fixes in connector/encoder/bridge docs (Daniel, Lyude, Laurent)
-connector: Allow more than 3 possible encoders for a connector (José)
-dp_cec: Allow a connector to be associated with a cec device (Dariusz)
-various: Fix some compile/sparse warnings (Ville)
-mm: Ensure mm node removals are properly serialised (Chris)
-panel: Specify the type of panel for drm_panels for later use (Laurent)
-panel: Use drm_panel_init to init device and funcs (Laurent)
-mst: Refactors and cleanups in anticipation of suspend/resume support (Lyude)
-vram:
-Add lazy unmapping for gem bo's (Thomas)
-Unify and rationalize vram mm and gem vram (Thomas)
-Expose vmap and vunmap for gem vram objects (Thomas)
-Allow objects to be pinned at the top of vram to avoid fragmentation (Thomas)
Driver Changes:
-various: Include drm_bridge.h instead of relying on drm_crtc.h (Boris)
-ast/mgag200: Refactor show_cursor(), move cursor to top of video mem (Thomas)
-komeda:
-Add error event printing (behind CONFIG) and reg dump support (Lowry)
-Add suspend/resume support (Lowry)
-Workaround D71 shadow registers not flushing on disable (Lowry)
-meson: Add suspend/resume support (Neil)
-omap: Miscellaneous refactors and improvements (Tomi/Jyri)
-panfrost/shmem: Silence lockdep by using mutex_trylock (Rob)
-panfrost: Miscellaneous small fixes (Rob/Steven)
-sti: Fix warnings (Benjamin/Linus)
-sun4i:
-Add vcc-dsi regulator to sun6i_mipi_dsi (Jagan)
-A few patches to figure out the DRQ/start delay calc on dsi (Jagan/Icenowy)
-virtio:
-Add module param to switch resource reuse workaround on/off (Gerd)
-Avoid calling vmexit while holding spinlock (Gerd)
-Use gem shmem helpers instead of ttm (Gerd)
-Accommodate command buffer allocations too big for cma (David)
Cc: Rob Herring <robh@kernel.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Lyude Paul <lyude@redhat.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Dariusz Marcinkiewicz <darekm@google.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Raymond Smith <raymond.smith@arm.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Mihail Atanassov <Mihail.Atanassov@arm.com>
Cc: Lowry Li <Lowry.Li@arm.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Jyri Sarha <jsarha@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Benjamin Gaignard <benjamin.gaignard@st.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Jagan Teki <jagan@amarulasolutions.com>
Cc: Icenowy Zheng <icenowy@aosc.io>
Cc: Iago Toral Quiroga <itoral@igalia.com>
Cc: David Riley <davidriley@chromium.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
# gpg: Signature made Thu 10 Oct 2019 01:00:47 AM AEST
# gpg: using RSA key 732C002572DCAF79
# gpg: Can't check signature: public key not found
# Conflicts:
# drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
# drivers/gpu/drm/i915/i915_drv.c
# drivers/gpu/drm/i915/i915_gem.c
# drivers/gpu/drm/i915/i915_gem_gtt.c
# drivers/gpu/drm/i915/i915_vma.c
From: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20191009150825.GA227673@art_vandelay
UAPI Changes:
- Never allow userptr into the mappable GGTT (Chris)
No existing users. Avoid anyone from even trying to
spare a deadlock scenario.
Cross-subsystem Changes:
Core Changes:
Driver Changes:
- Eliminate struct_mutex use as BKL! (Chris)
Only used for execbuf serialisation.
- Initialize DDI TC and TBT ports (D-I) on Tigerlake (Lucas)
- Fix DKL link training for 2.7GHz and 1.62GHz (Jose)
- Add Tigerlake DKL PHY programming sequences (Clinton)
- Add Tigerlake Thunderbolt PLL divider values (Imre)
- drm/i915: Use helpers for drm_mm_node booleans (Chris)
- Restrict L3 remapping sysfs interface to dwords (Chris)
- Fix audio power up sequence for gen10+ display (Kai)
- Skip redundant execlist resubmission (Chris)
- Only unwedge if we can reset GPU first (Chris)
- Initialise breadcrumb lists on the virtual engine (Chris)
- Don't rely on kernel context existing during early errors (Matt A)
- Update Icelake+ MG_DP_MODE programming table (Clinton)
- Update DMC firmware for Icelake (Anusha)
- Downgrade DP MST error after unplugging TypeC cable (Srinivasan)
- Limit MST modes based on plane size too (Ville)
- Polish intel_tv_mode_valid() (Ville)
- Fix g4x sprite scaling stride check with GTT remapping (Ville)
- Don't advertize non-exisiting crtcs (Ville)
- Clean up encoder->crtc_mask setup (Ville)
- Use tc_port instead of port parameter to MG registers (Jose)
- Remove static variable for aux last status (Jani)
- Implement a better i945gm vblank irq vs. C-states workaround (Ville)
- Make the object creation interface consistent (CQ)
- Rename intel_vga_msr_write() to intel_vga_reset_io_mem() (Jani, Ville)
- Eliminate previous drm_dbg/drm_err usage (Jani)
- Move gmbus setup down to intel_modeset_init() (Jani)
- Abstract all vgaarb access to intel_vga.[ch] (Jani)
- Split out i915_switcheroo.[ch] from i915_drv.c (Jani)
- Use intel_gt in has_reset* (Chris)
- Eliminate return value for i915_gem_init_early (Matt A)
- Selftest improvements (Chris)
- Update HuC firmware header version number format (Daniele)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191007134801.GA24313@jlahtine-desk.ger.corp.intel.com
With the introduction of ctx->engines[] we allow multiple logical
contexts to be used on the same engine (e.g. with virtual engines).
According to bspec, aach logical context requires a unique tag in order
for context-switching to occur correctly between them. [Simple
experiments show that it is not so easy to trick the HW into performing
a lite-restore with matching logical IDs, though my memory from early
Broadwell experiments do suggest that it should be generating
lite-restores.]
We only need to keep a unique tag for the active lifetime of the
context, and for as long as we need to identify that context. The HW
uses the tag to determine if it should use a lite-restore (why not the
LRCA?) and passes the tag back for various status identifies. The only
status we need to track is for OA, so when using perf, we assign the
specific context a unique tag.
v2: Calculate required number of tags to fill ELSP.
Fixes: 976b55f0e1 ("drm/i915: Allow a context to define its set of engines")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111895
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004134015.13204-14-chris@chris-wilson.co.uk
