#!/usr/bin/perl -w
#
# Build a static ASN.1 Object Identified (OID) registry
#
# Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
# Written by David Howells (dhowells@redhat.com)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public Licence
# as published by the Free Software Foundation; either version
# 2 of the Licence, or (at your option) any later version.
#

use strict;

my @names = ();
my @oids = ();

if ($#ARGV != 1) {
    print STDERR "Format: ", $0, " <in-h-file> <out-c-file>\n";
    exit(2);
}

#
# Open the file to read from
#
open IN_FILE, "<$ARGV[0]" || die;
while (<IN_FILE>) {
    chomp;
    if (m!\s+OID_([a-zA-z][a-zA-Z0-9_]+),\s+/[*]\s+([012][.0-9]*)\s+[*]/!) {
	push @names, $1;
	push @oids, $2;
    }
}
close IN_FILE || die;

#
# Open the files to write into
#
open C_FILE, ">$ARGV[1]" or die;
print C_FILE "/*\n";
print C_FILE " * Automatically generated by ", $0, ".  Do not edit\n";
print C_FILE " */\n";

#
# Split the data up into separate lists and also determine the lengths of the
# encoded data arrays.
#
my @indices = ();
my @lengths = ();
my $total_length = 0;

for (my $i = 0; $i <= $#names; $i++) {
    my $name = $names[$i];
    my $oid = $oids[$i];

    my @components = split(/[.]/, $oid);

    # Determine the encoded length of this OID
    my $size = $#components;
    for (my $loop = 2; $loop <= $#components; $loop++) {
	my $c = $components[$loop];

	# We will base128 encode the number
	my $tmp = ($c == 0) ? 0 : int(log($c)/log(2));
	$tmp = int($tmp / 7);
	$size += $tmp;
    }
    push @lengths, $size;
    push @indices, $total_length;
    $total_length += $size;
}

#
# Emit the look-up-by-OID index table
#
print C_FILE "\n";
if ($total_length <= 255) {
    print C_FILE "static const unsigned char oid_index[OID__NR + 1] = {\n";
} else {
    print C_FILE "static const unsigned short oid_index[OID__NR + 1] = {\n";
}
for (my $i = 0; $i <= $#names; $i++) {
    print C_FILE "\t[OID_", $names[$i], "] = ", $indices[$i], ",\n"
}
print C_FILE "\t[OID__NR] = ", $total_length, "\n";
print C_FILE "};\n";

#
# Encode the OIDs
#
my @encoded_oids = ();

for (my $i = 0; $i <= $#names; $i++) {
    my @octets = ();

    my @components = split(/[.]/, $oids[$i]);

    push @octets, $components[0] * 40 + $components[1];

    for (my $loop = 2; $loop <= $#components; $loop++) {
	my $c = $components[$loop];

	# Base128 encode the number
	my $tmp = ($c == 0) ? 0 : int(log($c)/log(2));
	$tmp = int($tmp / 7);

	for (; $tmp > 0; $tmp--) {
	    push @octets, (($c >> $tmp * 7) & 0x7f) | 0x80;
	}
	push @octets, $c & 0x7f;
    }

    push @encoded_oids, \@octets;
}

#
# Create a hash value for each OID
#
my @hash_values = ();
for (my $i = 0; $i <= $#names; $i++) {
    my @octets = @{$encoded_oids[$i]};

    my $hash = $#octets;
    foreach (@octets) {
	$hash += $_ * 33;
    }

    $hash = ($hash >> 24) ^ ($hash >> 16) ^ ($hash >> 8) ^ ($hash);

    push @hash_values, $hash & 0xff;
}

#
# Emit the OID data
#
print C_FILE "\n";
print C_FILE "static const unsigned char oid_data[", $total_length, "] = {\n";
for (my $i = 0; $i <= $#names; $i++) {
    my @octets = @{$encoded_oids[$i]};
    print C_FILE "\t";
    print C_FILE $_, ", " foreach (@octets);
    print C_FILE "\t// ", $names[$i];
    print C_FILE "\n";
}
print C_FILE "};\n";

#
# Build the search index table (ordered by length then hash then content)
#
my @index_table = ( 0 .. $#names );

@index_table = sort {
    my @octets_a = @{$encoded_oids[$a]};
    my @octets_b = @{$encoded_oids[$b]};

    return $hash_values[$a] <=> $hash_values[$b]
	if ($hash_values[$a] != $hash_values[$b]);
    return $#octets_a <=> $#octets_b
	if ($#octets_a != $#octets_b);
    for (my $i = $#octets_a; $i >= 0; $i--) {
	return $octets_a[$i] <=> $octets_b[$i]
	    if ($octets_a[$i] != $octets_b[$i]);
    }
    return 0;

} @index_table;

#
# Emit the search index and hash value table
#
print C_FILE "\n";
print C_FILE "static const struct {\n";
print C_FILE "\tunsigned char hash;\n";
if ($#names <= 255) {
    print C_FILE "\tenum OID oid : 8;\n";
} else {
    print C_FILE "\tenum OID oid : 16;\n";
}
print C_FILE "} oid_search_table[OID__NR] = {\n";
for (my $i = 0; $i <= $#names; $i++) {
    my @octets = @{$encoded_oids[$index_table[$i]]};
    printf(C_FILE "\t[%3u] = { %3u, OID_%-35s }, // ",
	   $i,
	   $hash_values[$index_table[$i]],
	   $names[$index_table[$i]]);
    printf C_FILE "%02x", $_ foreach (@octets);
    print C_FILE "\n";
}
print C_FILE "};\n";

#
# Emit the OID debugging name table
#
#print C_FILE "\n";
#print C_FILE "const char *const oid_name_table[OID__NR + 1] = {\n";
#
#for (my $i = 0; $i <= $#names; $i++) {
#    print C_FILE "\t\"", $names[$i], "\",\n"
#}
#print C_FILE "\t\"Unknown-OID\"\n";
#print C_FILE "};\n";

#
# Polish off
#
close C_FILE or die;
f98194e4f6b6cae7</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/clocksource?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/include/clocksource?id=79c6f448c8b79c321e4a1f31f98194e4f6b6cae7'>include/clocksource</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/clocksource?id=0c744ea4f77d72b3dcebb7a8f2684633ec79be88'>0c744ea4f77d72b3dcebb7a8f2684633ec79be88</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/clocksource?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 'include/clocksource')</div><table summary='diffstat' class='diffstat'>