fdo-mirrors/mesa
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/mesa/mesa.git synced 2026-05-24 06:18:10 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

pco: conditionally spill shared memory to global memory

Browse source 
Spills shared memory based on a fixed threshold, currently set to 75%.
This is to account for other usage of the common store.

Signed-off-by: Simon Perretta <simon.perretta@imgtec.com>
Acked-by: Frank Binns <frank.binns@imgtec.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/41545>
This commit is contained in:
Simon Perretta 2026-05-13 13:06:18 +01:00 • committed by Marge Bot
parent cba2833e0d
commit 657ecb93b5
1 changed files with 29 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

30
src/imagination/pco/pco_nir.c
View file

@ -18,6 +18,10 @@
#include <stdio.h>
/* TODO: Spill only if needed rather than requiring on a threshold. */
/** Shared memory spill threshold (0.0f-1.0f). */
#define PCO_SHMEM_THRESHOLD (0.75f)
/** SPIR-V to NIR options. */
static const struct spirv_to_nir_options spirv_options = {
.environment = NIR_SPIRV_VULKAN,
@ -782,6 +786,28 @@ static bool robustness_filter(const nir_intrinsic_instr *intr,
return false;
}
/**
* \brief Returns if shared memory should be spilled according to the threshold.
*
* \param[in,out] ctx PCO compiler context.
* \param[in] shared_size The shared memory size in bytes.
* \return True if shared memory should be spilled, else false.
*/
static inline bool should_spill_shmem(const pco_ctx *ctx, unsigned shared_size)
{
if (!shared_size)
return false;
const unsigned max_shmem_regs =
ctx->dev_runtime_info->cdm_max_local_mem_size_regs;
assert(max_shmem_regs);
/* Dword -> byte granularity. */
const unsigned max_shmem = max_shmem_regs << 2u;
return ((float)shared_size / (float)max_shmem) > PCO_SHMEM_THRESHOLD;
}
/**
* \brief Lowers a NIR shader.
*
@ -852,7 +878,9 @@ void pco_lower_nir(pco_ctx *ctx, nir_shader *nir, pco_data *data)
if (data->common.robust_buffer_access)
NIR_PASS(_, nir, nir_lower_robust_access, robustness_filter, NULL);
if (nir->info.stage == MESA_SHADER_COMPUTE && PCO_DEBUG(GLOBAL_SHMEM)) {
if (nir->info.stage == MESA_SHADER_COMPUTE &&
(PCO_DEBUG(GLOBAL_SHMEM) ||
should_spill_shmem(ctx, nir->info.shared_size))) {
unsigned usc_slots = PVR_GET_FEATURE_VALUE(ctx->dev_info, usc_slots, 0U);
NIR_PASS(_, nir, pco_nir_lower_shared_io_to_global, usc_slots);
data->cs.global_shmem = true;