/*
 * Unified UUID/GUID definition
 *
 * Copyright (C) 2009, 2016 Intel Corp.
 *	Huang Ying <ying.huang@intel.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation;
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/uuid.h>
#include <linux/random.h>

const u8 uuid_le_index[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
EXPORT_SYMBOL(uuid_le_index);
const u8 uuid_be_index[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
EXPORT_SYMBOL(uuid_be_index);

/***************************************************************
 * Random UUID interface
 *
 * Used here for a Boot ID, but can be useful for other kernel
 * drivers.
 ***************************************************************/

/*
 * Generate random UUID
 */
void generate_random_uuid(unsigned char uuid[16])
{
	get_random_bytes(uuid, 16);
	/* Set UUID version to 4 --- truly random generation */
	uuid[6] = (uuid[6] & 0x0F) | 0x40;
	/* Set the UUID variant to DCE */
	uuid[8] = (uuid[8] & 0x3F) | 0x80;
}
EXPORT_SYMBOL(generate_random_uuid);

static void __uuid_gen_common(__u8 b[16])
{
	prandom_bytes(b, 16);
	/* reversion 0b10 */
	b[8] = (b[8] & 0x3F) | 0x80;
}

void uuid_le_gen(uuid_le *lu)
{
	__uuid_gen_common(lu->b);
	/* version 4 : random generation */
	lu->b[7] = (lu->b[7] & 0x0F) | 0x40;
}
EXPORT_SYMBOL_GPL(uuid_le_gen);

void uuid_be_gen(uuid_be *bu)
{
	__uuid_gen_common(bu->b);
	/* version 4 : random generation */
	bu->b[6] = (bu->b[6] & 0x0F) | 0x40;
}
EXPORT_SYMBOL_GPL(uuid_be_gen);

/**
  * uuid_is_valid - checks if UUID string valid
  * @uuid:	UUID string to check
  *
  * Description:
  * It checks if the UUID string is following the format:
  *	xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
  * where x is a hex digit.
  *
  * Return: true if input is valid UUID string.
  */
bool uuid_is_valid(const char *uuid)
{
	unsigned int i;

	for (i = 0; i < UUID_STRING_LEN; i++) {
		if (i == 8 || i == 13 || i == 18 || i == 23) {
			if (uuid[i] != '-')
				return false;
		} else if (!isxdigit(uuid[i])) {
			return false;
		}
	}

	return true;
}
EXPORT_SYMBOL(uuid_is_valid);

static int __uuid_to_bin(const char *uuid, __u8 b[16], const u8 ei[16])
{
	static const u8 si[16] = {0,2,4,6,9,11,14,16,19,21,24,26,28,30,32,34};
	unsigned int i;

	if (!uuid_is_valid(uuid))
		return -EINVAL;

	for (i = 0; i < 16; i++) {
		int hi = hex_to_bin(uuid[si[i] + 0]);
		int lo = hex_to_bin(uuid[si[i] + 1]);

		b[ei[i]] = (hi << 4) | lo;
	}

	return 0;
}

int uuid_le_to_bin(const char *uuid, uuid_le *u)
{
	return __uuid_to_bin(uuid, u->b, uuid_le_index);
}
EXPORT_SYMBOL(uuid_le_to_bin);

int uuid_be_to_bin(const char *uuid, uuid_be *u)
{
	return __uuid_to_bin(uuid, u->b, uuid_be_index);
}
EXPORT_SYMBOL(uuid_be_to_bin);
 href='/cgit.cgi/linux/net-next.git/commit/tools/testing/selftests?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>selftests</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/testing/selftests/ptrace?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>ptrace</a>/<a href='/cgit.cgi/linux/net-next.git/commit/tools/testing/selftests/ptrace/.gitignore?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>.gitignore</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;</td><td class='right'>2017-01-30 19:27:10 -0500</td></tr>
<tr><th>committer</th><td>Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;</td><td class='right'>2017-01-31 09:13:49 -0500</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/testing/selftests/ptrace/.gitignore?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>79c6f448c8b79c321e4a1f31f98194e4f6b6cae7</a> (<a href='/cgit.cgi/linux/net-next.git/patch/tools/testing/selftests/ptrace/.gitignore?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>370efda701f03cccf21e02bb1fdd3b852547d75c</a> /<a href='/cgit.cgi/linux/net-next.git/tree/tools/testing/selftests/ptrace/.gitignore?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>tools/testing/selftests/ptrace/.gitignore</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/tools/testing/selftests/ptrace/.gitignore?id=0c744ea4f77d72b3dcebb7a8f2684633ec79be88'>0c744ea4f77d72b3dcebb7a8f2684633ec79be88</a> (<a href='/cgit.cgi/linux/net-next.git/diff/tools/testing/selftests/ptrace/.gitignore?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7&amp;id2=0c744ea4f77d72b3dcebb7a8f2684633ec79be88'>diff</a>)</td></tr></table>
<div class='commit-subject'>tracing: Fix hwlat kthread migration</div><div class='commit-msg'>The hwlat tracer creates a kernel thread at start of the tracer. It is
pinned to a single CPU and will move to the next CPU after each period of
running. If the user modifies the migration thread's affinity, it will not
change after that happens.

The original code created the thread at the first instance it was called,
but later was changed to destroy the thread after the tracer was finished,
and would not be created until the next instance of the tracer was
established. The code that initialized the affinity was only called on the
initial instantiation of the tracer. After that, it was not initialized, and
the previous affinity did not match the current newly created one, making
it appear that the user modified the thread's affinity when it did not, and
the thread failed to migrate again.

Cc: stable@vger.kernel.org
Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs")
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>Diffstat</a> (limited to 'tools/testing/selftests/ptrace/.gitignore')</div><table summary='diffstat' class='diffstat'>