lib/raid/xor/xor-8regs-prefetch.c

Source file repositories/reference/linux-study-clean/lib/raid/xor/xor-8regs-prefetch.c

File Facts

System
Linux kernel
Corpus path
lib/raid/xor/xor-8regs-prefetch.c
Extension
.c
Size
3150 bytes
Lines
147
Domain
Kernel Services
Bucket
lib
Inferred role
Kernel Services: implementation source
Status
source implementation candidate

Why This File Exists

Shared kernel service surface used by multiple subsystems, including helpers, cryptography, virtualization support, and async I/O infrastructure.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/prefetch.h>
#include "xor_impl.h"

static void
xor_8regs_p_2(unsigned long bytes, unsigned long * __restrict p1,
	      const unsigned long * __restrict p2)
{
	long lines = bytes / (sizeof (long)) / 8 - 1;
	prefetchw(p1);
	prefetch(p2);

	do {
		prefetchw(p1+8);
		prefetch(p2+8);
 once_more:
		p1[0] ^= p2[0];
		p1[1] ^= p2[1];
		p1[2] ^= p2[2];
		p1[3] ^= p2[3];
		p1[4] ^= p2[4];
		p1[5] ^= p2[5];
		p1[6] ^= p2[6];
		p1[7] ^= p2[7];
		p1 += 8;
		p2 += 8;
	} while (--lines > 0);
	if (lines == 0)
		goto once_more;
}

static void
xor_8regs_p_3(unsigned long bytes, unsigned long * __restrict p1,
	      const unsigned long * __restrict p2,
	      const unsigned long * __restrict p3)
{
	long lines = bytes / (sizeof (long)) / 8 - 1;
	prefetchw(p1);
	prefetch(p2);
	prefetch(p3);

	do {
		prefetchw(p1+8);
		prefetch(p2+8);
		prefetch(p3+8);
 once_more:
		p1[0] ^= p2[0] ^ p3[0];
		p1[1] ^= p2[1] ^ p3[1];
		p1[2] ^= p2[2] ^ p3[2];
		p1[3] ^= p2[3] ^ p3[3];
		p1[4] ^= p2[4] ^ p3[4];
		p1[5] ^= p2[5] ^ p3[5];
		p1[6] ^= p2[6] ^ p3[6];
		p1[7] ^= p2[7] ^ p3[7];
		p1 += 8;
		p2 += 8;
		p3 += 8;
	} while (--lines > 0);
	if (lines == 0)
		goto once_more;
}

static void
xor_8regs_p_4(unsigned long bytes, unsigned long * __restrict p1,
	      const unsigned long * __restrict p2,
	      const unsigned long * __restrict p3,
	      const unsigned long * __restrict p4)
{
	long lines = bytes / (sizeof (long)) / 8 - 1;

	prefetchw(p1);
	prefetch(p2);
	prefetch(p3);
	prefetch(p4);

	do {
		prefetchw(p1+8);
		prefetch(p2+8);
		prefetch(p3+8);
		prefetch(p4+8);
 once_more:
		p1[0] ^= p2[0] ^ p3[0] ^ p4[0];
		p1[1] ^= p2[1] ^ p3[1] ^ p4[1];
		p1[2] ^= p2[2] ^ p3[2] ^ p4[2];
		p1[3] ^= p2[3] ^ p3[3] ^ p4[3];
		p1[4] ^= p2[4] ^ p3[4] ^ p4[4];
		p1[5] ^= p2[5] ^ p3[5] ^ p4[5];
		p1[6] ^= p2[6] ^ p3[6] ^ p4[6];
		p1[7] ^= p2[7] ^ p3[7] ^ p4[7];
		p1 += 8;

Annotation

Implementation Notes