cregit-Linux how code gets into the kernel

Release 4.10 crypto/xor.c

Directory: crypto
 * xor.c : Multiple Devices driver for Linux
 * Copyright (C) 1996, 1997, 1998, 1999, 2000,
 * Ingo Molnar, Matti Aarnio, Jakub Jelinek, Richard Henderson.
 * Dispatch optimized RAID-5 checksumming functions.
 * 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; either version 2, or (at your option)
 * any later version.
 * You should have received a copy of the GNU General Public License
 * (for example /usr/src/linux/COPYING); if not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

#define BH_TRACE 0
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/raid/xor.h>
#include <linux/jiffies.h>
#include <linux/preempt.h>
#include <asm/xor.h>


#define XOR_SELECT_TEMPLATE(x) (x)

/* The xor routines to use.  */

static struct xor_block_template *active_template;

void xor_blocks(unsigned int src_count, unsigned int bytes, void *dest, void **srcs) { unsigned long *p1, *p2, *p3, *p4; p1 = (unsigned long *) srcs[0]; if (src_count == 1) { active_template->do_2(bytes, dest, p1); return; } p2 = (unsigned long *) srcs[1]; if (src_count == 2) { active_template->do_3(bytes, dest, p1, p2); return; } p3 = (unsigned long *) srcs[2]; if (src_count == 3) { active_template->do_4(bytes, dest, p1, p2, p3); return; } p4 = (unsigned long *) srcs[3]; active_template->do_5(bytes, dest, p1, p2, p3, p4); }


dan williamsdan williams2514.97%240.00%
neil brownneil brown52.99%120.00%

EXPORT_SYMBOL(xor_blocks); /* Set of all registered templates. */ static struct xor_block_template *__initdata template_list; #define BENCH_SIZE (PAGE_SIZE)
static void __init do_xor_speed(struct xor_block_template *tmpl, void *b1, void *b2) { int speed; unsigned long now, j; int i, count, max; tmpl->next = template_list; template_list = tmpl; preempt_disable(); /* * Count the number of XORs done during a whole jiffy, and use * this to calculate the speed of checksumming. We use a 2-page * allocation to have guaranteed color L1-cache layout. */ max = 0; for (i = 0; i < 5; i++) { j = jiffies; count = 0; while ((now = jiffies) == j) cpu_relax(); while (time_before(jiffies, now + 1)) { mb(); /* prevent loop optimzation */ tmpl->do_2(BENCH_SIZE, b1, b2); mb(); count++; mb(); } if (count > max) max = count; } preempt_enable(); speed = max * (HZ * BENCH_SIZE / 1024); tmpl->speed = speed; printk(KERN_INFO " %-10s: %5d.%03d MB/sec\n", tmpl->name, speed / 1000, speed % 1000); }


jim kukunasjim kukunas2715.34%233.33%
dan williamsdan williams21.14%116.67%
jan beulichjan beulich10.57%116.67%

static int __init calibrate_xor_blocks(void) { void *b1, *b2; struct xor_block_template *f, *fastest; fastest = XOR_SELECT_TEMPLATE(NULL); if (fastest) { printk(KERN_INFO "xor: automatically using best " "checksumming function %-10s\n", fastest->name); goto out; } /* * Note: Since the memory is not actually used for _anything_ but to * test the XOR speed, we don't really want kmemcheck to warn about * reading uninitialized bytes here. */ b1 = (void *) __get_free_pages(GFP_KERNEL | __GFP_NOTRACK, 2); if (!b1) { printk(KERN_WARNING "xor: Yikes! No memory available.\n"); return -ENOMEM; } b2 = b1 + 2*PAGE_SIZE + BENCH_SIZE; /* * If this arch/cpu has a short-circuited selection, don't loop through * all the possible functions, just test the best one */ #define xor_speed(templ) do_xor_speed((templ), b1, b2) printk(KERN_INFO "xor: measuring software checksum speed\n"); XOR_TRY_TEMPLATES; fastest = template_list; for (f = fastest; f; f = f->next) if (f->speed > fastest->speed) fastest = f; printk(KERN_INFO "xor: using function: %s (%d.%03d MB/sec)\n", fastest->name, fastest->speed / 1000, fastest->speed % 1000); #undef xor_speed free_pages((unsigned long)b1, 2); out: active_template = fastest; return 0; }


martin schwidefskymartin schwidefsky2814.97%111.11%
andrew mortonandrew morton2513.37%111.11%
dan williamsdan williams84.28%222.22%
vegard nossumvegard nossum31.60%111.11%
herbert xuherbert xu10.53%111.11%
neil brownneil brown10.53%111.11%

static __exit void xor_exit(void) { }


neil brownneil brown8100.00%1100.00%

MODULE_LICENSE("GPL"); /* when built-in xor.o must initialize before drivers/md/md.o */ core_initcall(calibrate_xor_blocks); module_exit(xor_exit);

Overall Contributors

dan williamsdan williams437.01%210.53%
jim kukunasjim kukunas304.89%210.53%
martin schwidefskymartin schwidefsky284.57%15.26%
andrew mortonandrew morton254.08%15.26%
neil brownneil brown213.43%421.05%
herbert xuherbert xu132.12%15.26%
linus torvaldslinus torvalds60.98%210.53%
tejun heotejun heo30.49%15.26%
vegard nossumvegard nossum30.49%15.26%
jan beulichjan beulich20.33%15.26%
Directory: crypto
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