alistair23-linux/include/linux/raid/pq.h
Daniel Verkamp be85f93ae2 lib/raid6: add option to skip algo benchmarking
This is helpful for systems where fast startup time is important.
It is especially nice to avoid benchmarking RAID functions that are
never used (for example, BTRFS selects RAID6_PQ even if the parity RAID
mode is not in use).

This saves 250+ milliseconds of boot time on modern x86 and ARM systems
with a dozen or more available implementations.

The new option is defaulted to 'y' to match the previous behavior of
always benchmarking on init.

Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Signed-off-by: Shaohua Li <shli@fb.com>
2018-12-20 08:53:23 -08:00

198 lines
6.2 KiB
C

/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright 2003 H. Peter Anvin - All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, Inc., 53 Temple Place Ste 330,
* Boston MA 02111-1307, USA; either version 2 of the License, or
* (at your option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
#ifndef LINUX_RAID_RAID6_H
#define LINUX_RAID_RAID6_H
#ifdef __KERNEL__
/* Set to 1 to use kernel-wide empty_zero_page */
#define RAID6_USE_EMPTY_ZERO_PAGE 0
#include <linux/blkdev.h>
/* We need a pre-zeroed page... if we don't want to use the kernel-provided
one define it here */
#if RAID6_USE_EMPTY_ZERO_PAGE
# define raid6_empty_zero_page empty_zero_page
#else
extern const char raid6_empty_zero_page[PAGE_SIZE];
#endif
#else /* ! __KERNEL__ */
/* Used for testing in user space */
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stddef.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <sys/types.h>
/* Not standard, but glibc defines it */
#define BITS_PER_LONG __WORDSIZE
typedef uint8_t u8;
typedef uint16_t u16;
typedef uint32_t u32;
typedef uint64_t u64;
#ifndef PAGE_SIZE
# define PAGE_SIZE 4096
#endif
extern const char raid6_empty_zero_page[PAGE_SIZE];
#define __init
#define __exit
#ifndef __attribute_const__
# define __attribute_const__ __attribute__((const))
#endif
#define noinline __attribute__((noinline))
#define preempt_enable()
#define preempt_disable()
#define cpu_has_feature(x) 1
#define enable_kernel_altivec()
#define disable_kernel_altivec()
#define EXPORT_SYMBOL(sym)
#define EXPORT_SYMBOL_GPL(sym)
#define MODULE_LICENSE(licence)
#define MODULE_DESCRIPTION(desc)
#define subsys_initcall(x)
#define module_exit(x)
#define IS_ENABLED(x) (x)
#define CONFIG_RAID6_PQ_BENCHMARK 1
#endif /* __KERNEL__ */
/* Routine choices */
struct raid6_calls {
void (*gen_syndrome)(int, size_t, void **);
void (*xor_syndrome)(int, int, int, size_t, void **);
int (*valid)(void); /* Returns 1 if this routine set is usable */
const char *name; /* Name of this routine set */
int prefer; /* Has special performance attribute */
};
/* Selected algorithm */
extern struct raid6_calls raid6_call;
/* Various routine sets */
extern const struct raid6_calls raid6_intx1;
extern const struct raid6_calls raid6_intx2;
extern const struct raid6_calls raid6_intx4;
extern const struct raid6_calls raid6_intx8;
extern const struct raid6_calls raid6_intx16;
extern const struct raid6_calls raid6_intx32;
extern const struct raid6_calls raid6_mmxx1;
extern const struct raid6_calls raid6_mmxx2;
extern const struct raid6_calls raid6_sse1x1;
extern const struct raid6_calls raid6_sse1x2;
extern const struct raid6_calls raid6_sse2x1;
extern const struct raid6_calls raid6_sse2x2;
extern const struct raid6_calls raid6_sse2x4;
extern const struct raid6_calls raid6_altivec1;
extern const struct raid6_calls raid6_altivec2;
extern const struct raid6_calls raid6_altivec4;
extern const struct raid6_calls raid6_altivec8;
extern const struct raid6_calls raid6_avx2x1;
extern const struct raid6_calls raid6_avx2x2;
extern const struct raid6_calls raid6_avx2x4;
extern const struct raid6_calls raid6_avx512x1;
extern const struct raid6_calls raid6_avx512x2;
extern const struct raid6_calls raid6_avx512x4;
extern const struct raid6_calls raid6_s390vx8;
extern const struct raid6_calls raid6_vpermxor1;
extern const struct raid6_calls raid6_vpermxor2;
extern const struct raid6_calls raid6_vpermxor4;
extern const struct raid6_calls raid6_vpermxor8;
struct raid6_recov_calls {
void (*data2)(int, size_t, int, int, void **);
void (*datap)(int, size_t, int, void **);
int (*valid)(void);
const char *name;
int priority;
};
extern const struct raid6_recov_calls raid6_recov_intx1;
extern const struct raid6_recov_calls raid6_recov_ssse3;
extern const struct raid6_recov_calls raid6_recov_avx2;
extern const struct raid6_recov_calls raid6_recov_avx512;
extern const struct raid6_recov_calls raid6_recov_s390xc;
extern const struct raid6_recov_calls raid6_recov_neon;
extern const struct raid6_calls raid6_neonx1;
extern const struct raid6_calls raid6_neonx2;
extern const struct raid6_calls raid6_neonx4;
extern const struct raid6_calls raid6_neonx8;
/* Algorithm list */
extern const struct raid6_calls * const raid6_algos[];
extern const struct raid6_recov_calls *const raid6_recov_algos[];
int raid6_select_algo(void);
/* Return values from chk_syndrome */
#define RAID6_OK 0
#define RAID6_P_BAD 1
#define RAID6_Q_BAD 2
#define RAID6_PQ_BAD 3
/* Galois field tables */
extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256)));
extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256)));
extern const u8 raid6_gfexp[256] __attribute__((aligned(256)));
extern const u8 raid6_gflog[256] __attribute__((aligned(256)));
extern const u8 raid6_gfinv[256] __attribute__((aligned(256)));
extern const u8 raid6_gfexi[256] __attribute__((aligned(256)));
/* Recovery routines */
extern void (*raid6_2data_recov)(int disks, size_t bytes, int faila, int failb,
void **ptrs);
extern void (*raid6_datap_recov)(int disks, size_t bytes, int faila,
void **ptrs);
void raid6_dual_recov(int disks, size_t bytes, int faila, int failb,
void **ptrs);
/* Some definitions to allow code to be compiled for testing in userspace */
#ifndef __KERNEL__
# define jiffies raid6_jiffies()
# define printk printf
# define pr_err(format, ...) fprintf(stderr, format, ## __VA_ARGS__)
# define pr_info(format, ...) fprintf(stdout, format, ## __VA_ARGS__)
# define GFP_KERNEL 0
# define __get_free_pages(x, y) ((unsigned long)mmap(NULL, PAGE_SIZE << (y), \
PROT_READ|PROT_WRITE, \
MAP_PRIVATE|MAP_ANONYMOUS,\
0, 0))
# define free_pages(x, y) munmap((void *)(x), PAGE_SIZE << (y))
static inline void cpu_relax(void)
{
/* Nothing */
}
#undef HZ
#define HZ 1000
static inline uint32_t raid6_jiffies(void)
{
struct timeval tv;
gettimeofday(&tv, NULL);
return tv.tv_sec*1000 + tv.tv_usec/1000;
}
#endif /* ! __KERNEL__ */
#endif /* LINUX_RAID_RAID6_H */