The normal encode pass writes batches to a section in build scratch
memory. Those batches contain information about the internal node and
the primitive nodes. The encoder is split to avoid the register
pressure of the compressor and maximize occupancy.
The compressor works in two passes because one pass can not guarantee
that every primitive node (except) has at least two triangles. This
guarantee is used to advertise a smaller acceleration structure size to
the application.
During compression, every invocation processes at most two triangles.
Groups of 8 invocations are used to support the maximum triangle count
of 16 that the hardware supports.
The first step of compression is loading the triangle(s). Shared
vertices are deduplicated early to avoid doing it in the compression
loop. The compression loop tries to add triangles to a list of triangles
until the computed node size needed for storing the triangles reaches
the hardware node size. For this, each invocation first deduplicates
vertices with the triangles that have already been picked. It then
computes the node size of the picked triangles plus the candidate
triangles of the current invocation. The invocation that computed the
smallest size is added to the list.
Because it may not be possible to fit every triangle into the same node,
there can be multiple hardware nodes which are written in parallel for
optimal performance. If there are no nodes with only one triangle, all
nodes are written. If there is, compression of the batch is aborted and
the index of the batch is written to build scratch memory. The second
compression pass will repeat the steps above but only for those aborted
batches. The nodes with only one triangle can and are now merged.
It can not be determined during box node encode which triangles will be
compressed together so the encoder also has to fix up the parent box
node's child infos.
Reviewed-by: Natalie Vock <natalie.vock@gmx.de>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36965>
Mesh shader workgroups always have the same amount of subgroups.
When the API workgroup size is the same as the real workgroup
size, this is a small optimization (using a constant instead of
a shader arg).
When the API workgroup size is smaller than the real workgroup
size (eg. when the number of output vertices or primitves is
greater than the API workgroup size on RDNA 2), this fixes a
potential bug because num_subgroups would return the "real"
workgroup size instead of the API one.
Cc: mesa-stable
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Qiang Yu <yuq825@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37947>
Until we have a stable kernel which contains these fixes.
This applies to all jobs except NAVI21/NAVI31 which still use 6.6 and
POLARIS10 which is stucked to 6.15.9 for now.
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37934>
This was something that came up in the slop MR. Not sure it's actually a
good idea or not but kind of curious what people think, given we have a
sound tool (Coccinelle) to do the transform. Saves a redundant branch
but means extra noninlined function calls.. likely no actual perf impact
but saves some code.
Via Coccinelle patches:
@@
expression ptr;
@@
-if (ptr) {
-free(ptr);
-}
+free(ptr);
@@
expression ptr;
@@
-if (ptr) {
-FREE(ptr);
-}
+FREE(ptr);
@@
expression ptr;
@@
-if (ptr) {
-ralloc_free(ptr);
-}
+ralloc_free(ptr);
@@
expression ptr;
@@
-if (ptr != NULL) {
-free(ptr);
-}
-
+free(ptr);
@@
expression ptr;
@@
-if (ptr != NULL) {
-FREE(ptr);
-}
-
+FREE(ptr);
@@
expression ptr;
@@
-if (ptr != NULL) {
-ralloc_free(ptr);
-}
-
+ralloc_free(ptr);
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@intel.com>
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com> [v3d]
Reviewed-by: Yiwei Zhang <zzyiwei@chromium.org> [venus]
Reviewed-by: Frank Binns <frank.binns@imgtec.com> [powervr]
Reviewed-by: Janne Grunau <j@jannau.net> [asahi]
Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com> [radv]
Reviewed-by: Job Noorman <jnoorman@igalia.com> [ir3]
Acked-by: Marek Olšák <maraeo@gmail.com>
Acked-by: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Acked-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Acked-by: Job Noorman <jnoorman@igalia.com>
Acked-by: Yonggang Luo <luoyonggang@gmail.com>
Acked-by: Christian Gmeiner <cgmeiner@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37892>
Mitigate a GPU hang in Dota 2 and Rise of the Tomb Raider
by reducing the primitive rate for triangle lists.
This workaround is not documented by AMD and may not be correct.
The problem isn't well understood and needs further investigation
to narrow down what the root cause is. Until then, it's better
to give users something that works, even if not optimal.
Cc: mesa-stable
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37885>
