drivers/gpu/tests/gpu_random.c

Source file repositories/reference/linux-study-clean/drivers/gpu/tests/gpu_random.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/tests/gpu_random.c
Extension
.c
Size
1036 bytes
Lines
45
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
#include <linux/bitops.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/types.h>

#include "gpu_random.h"

u32 gpu_prandom_u32_max_state(u32 ep_ro, struct rnd_state *state)
{
	return upper_32_bits((u64)prandom_u32_state(state) * ep_ro);
}
EXPORT_SYMBOL(gpu_prandom_u32_max_state);

void gpu_random_reorder(unsigned int *order, unsigned int count,
			struct rnd_state *state)
{
	unsigned int i, j;

	for (i = 0; i < count; ++i) {
		BUILD_BUG_ON(sizeof(unsigned int) > sizeof(u32));
		j = gpu_prandom_u32_max_state(count, state);
		swap(order[i], order[j]);
	}
}
EXPORT_SYMBOL(gpu_random_reorder);

unsigned int *gpu_random_order(unsigned int count, struct rnd_state *state)
{
	unsigned int *order, i;

	order = kmalloc_array(count, sizeof(*order), GFP_KERNEL);
	if (!order)
		return order;

	for (i = 0; i < count; i++)
		order[i] = i;

	gpu_random_reorder(order, count, state);
	return order;
}
EXPORT_SYMBOL(gpu_random_order);

Annotation

Implementation Notes