kernel/Documentation/trace/postprocess/trace-pagealloc-postprocess.pl
2024-07-22 17:22:30 +08:00

419 lines
12 KiB
Perl

#!/usr/bin/env perl
# This is a POC (proof of concept or piece of crap, take your pick) for reading the
# text representation of trace output related to page allocation. It makes an attempt
# to extract some high-level information on what is going on. The accuracy of the parser
# may vary considerably
#
# Example usage: trace-pagealloc-postprocess.pl < /sys/kernel/debug/tracing/trace_pipe
# other options
# --prepend-parent Report on the parent proc and PID
# --read-procstat If the trace lacks process info, get it from /proc
# --ignore-pid Aggregate processes of the same name together
#
# Copyright (c) IBM Corporation 2009
# Author: Mel Gorman <mel@csn.ul.ie>
use strict;
use Getopt::Long;
# Tracepoint events
use constant MM_PAGE_ALLOC => 1;
use constant MM_PAGE_FREE => 2;
use constant MM_PAGE_FREE_BATCHED => 3;
use constant MM_PAGE_PCPU_DRAIN => 4;
use constant MM_PAGE_ALLOC_ZONE_LOCKED => 5;
use constant MM_PAGE_ALLOC_EXTFRAG => 6;
use constant EVENT_UNKNOWN => 7;
# Constants used to track state
use constant STATE_PCPU_PAGES_DRAINED => 8;
use constant STATE_PCPU_PAGES_REFILLED => 9;
# High-level events extrapolated from tracepoints
use constant HIGH_PCPU_DRAINS => 10;
use constant HIGH_PCPU_REFILLS => 11;
use constant HIGH_EXT_FRAGMENT => 12;
use constant HIGH_EXT_FRAGMENT_SEVERE => 13;
use constant HIGH_EXT_FRAGMENT_MODERATE => 14;
use constant HIGH_EXT_FRAGMENT_CHANGED => 15;
my %perprocesspid;
my %perprocess;
my $opt_ignorepid;
my $opt_read_procstat;
my $opt_prepend_parent;
# Catch sigint and exit on request
my $sigint_report = 0;
my $sigint_exit = 0;
my $sigint_pending = 0;
my $sigint_received = 0;
sub sigint_handler {
my $current_time = time;
if ($current_time - 2 > $sigint_received) {
print "SIGINT received, report pending. Hit ctrl-c again to exit\n";
$sigint_report = 1;
} else {
if (!$sigint_exit) {
print "Second SIGINT received quickly, exiting\n";
}
$sigint_exit++;
}
if ($sigint_exit > 3) {
print "Many SIGINTs received, exiting now without report\n";
exit;
}
$sigint_received = $current_time;
$sigint_pending = 1;
}
$SIG{INT} = "sigint_handler";
# Parse command line options
GetOptions(
'ignore-pid' => \$opt_ignorepid,
'read-procstat' => \$opt_read_procstat,
'prepend-parent' => \$opt_prepend_parent,
);
# Defaults for dynamically discovered regex's
my $regex_fragdetails_default = 'page=([0-9a-f]*) pfn=([0-9]*) alloc_order=([-0-9]*) fallback_order=([-0-9]*) pageblock_order=([-0-9]*) alloc_migratetype=([-0-9]*) fallback_migratetype=([-0-9]*) fragmenting=([-0-9]) change_ownership=([-0-9])';
# Dyanically discovered regex
my $regex_fragdetails;
# Static regex used. Specified like this for readability and for use with /o
# (process_pid) (cpus ) ( time ) (tpoint ) (details)
my $regex_traceevent = '\s*([a-zA-Z0-9-]*)\s*(\[[0-9]*\])\s*([0-9.]*):\s*([a-zA-Z_]*):\s*(.*)';
my $regex_statname = '[-0-9]*\s\((.*)\).*';
my $regex_statppid = '[-0-9]*\s\(.*\)\s[A-Za-z]\s([0-9]*).*';
sub generate_traceevent_regex {
my $event = shift;
my $default = shift;
my $regex;
# Read the event format or use the default
if (!open (FORMAT, "/sys/kernel/debug/tracing/events/$event/format")) {
$regex = $default;
} else {
my $line;
while (!eof(FORMAT)) {
$line = <FORMAT>;
if ($line =~ /^print fmt:\s"(.*)",.*/) {
$regex = $1;
$regex =~ s/%p/\([0-9a-f]*\)/g;
$regex =~ s/%d/\([-0-9]*\)/g;
$regex =~ s/%lu/\([0-9]*\)/g;
}
}
}
# Verify fields are in the right order
my $tuple;
foreach $tuple (split /\s/, $regex) {
my ($key, $value) = split(/=/, $tuple);
my $expected = shift;
if ($key ne $expected) {
print("WARNING: Format not as expected '$key' != '$expected'");
$regex =~ s/$key=\((.*)\)/$key=$1/;
}
}
if (defined shift) {
die("Fewer fields than expected in format");
}
return $regex;
}
$regex_fragdetails = generate_traceevent_regex("kmem/mm_page_alloc_extfrag",
$regex_fragdetails_default,
"page", "pfn",
"alloc_order", "fallback_order", "pageblock_order",
"alloc_migratetype", "fallback_migratetype",
"fragmenting", "change_ownership");
sub read_statline($) {
my $pid = $_[0];
my $statline;
if (open(STAT, "/proc/$pid/stat")) {
$statline = <STAT>;
close(STAT);
}
if ($statline eq '') {
$statline = "-1 (UNKNOWN_PROCESS_NAME) R 0";
}
return $statline;
}
sub guess_process_pid($$) {
my $pid = $_[0];
my $statline = $_[1];
if ($pid == 0) {
return "swapper-0";
}
if ($statline !~ /$regex_statname/o) {
die("Failed to math stat line for process name :: $statline");
}
return "$1-$pid";
}
sub parent_info($$) {
my $pid = $_[0];
my $statline = $_[1];
my $ppid;
if ($pid == 0) {
return "NOPARENT-0";
}
if ($statline !~ /$regex_statppid/o) {
die("Failed to match stat line process ppid:: $statline");
}
# Read the ppid stat line
$ppid = $1;
return guess_process_pid($ppid, read_statline($ppid));
}
sub process_events {
my $traceevent;
my $process_pid;
my $cpus;
my $timestamp;
my $tracepoint;
my $details;
my $statline;
# Read each line of the event log
EVENT_PROCESS:
while ($traceevent = <STDIN>) {
if ($traceevent =~ /$regex_traceevent/o) {
$process_pid = $1;
$tracepoint = $4;
if ($opt_read_procstat || $opt_prepend_parent) {
$process_pid =~ /(.*)-([0-9]*)$/;
my $process = $1;
my $pid = $2;
$statline = read_statline($pid);
if ($opt_read_procstat && $process eq '') {
$process_pid = guess_process_pid($pid, $statline);
}
if ($opt_prepend_parent) {
$process_pid = parent_info($pid, $statline) . " :: $process_pid";
}
}
# Unnecessary in this script. Uncomment if required
# $cpus = $2;
# $timestamp = $3;
} else {
next;
}
# Perl Switch() sucks majorly
if ($tracepoint eq "mm_page_alloc") {
$perprocesspid{$process_pid}->{MM_PAGE_ALLOC}++;
} elsif ($tracepoint eq "mm_page_free") {
$perprocesspid{$process_pid}->{MM_PAGE_FREE}++
} elsif ($tracepoint eq "mm_page_free_batched") {
$perprocesspid{$process_pid}->{MM_PAGE_FREE_BATCHED}++;
} elsif ($tracepoint eq "mm_page_pcpu_drain") {
$perprocesspid{$process_pid}->{MM_PAGE_PCPU_DRAIN}++;
$perprocesspid{$process_pid}->{STATE_PCPU_PAGES_DRAINED}++;
} elsif ($tracepoint eq "mm_page_alloc_zone_locked") {
$perprocesspid{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED}++;
$perprocesspid{$process_pid}->{STATE_PCPU_PAGES_REFILLED}++;
} elsif ($tracepoint eq "mm_page_alloc_extfrag") {
# Extract the details of the event now
$details = $5;
my ($page, $pfn);
my ($alloc_order, $fallback_order, $pageblock_order);
my ($alloc_migratetype, $fallback_migratetype);
my ($fragmenting, $change_ownership);
if ($details !~ /$regex_fragdetails/o) {
print "WARNING: Failed to parse mm_page_alloc_extfrag as expected\n";
next;
}
$perprocesspid{$process_pid}->{MM_PAGE_ALLOC_EXTFRAG}++;
$page = $1;
$pfn = $2;
$alloc_order = $3;
$fallback_order = $4;
$pageblock_order = $5;
$alloc_migratetype = $6;
$fallback_migratetype = $7;
$fragmenting = $8;
$change_ownership = $9;
if ($fragmenting) {
$perprocesspid{$process_pid}->{HIGH_EXT_FRAG}++;
if ($fallback_order <= 3) {
$perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_SEVERE}++;
} else {
$perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_MODERATE}++;
}
}
if ($change_ownership) {
$perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_CHANGED}++;
}
} else {
$perprocesspid{$process_pid}->{EVENT_UNKNOWN}++;
}
# Catch a full pcpu drain event
if ($perprocesspid{$process_pid}->{STATE_PCPU_PAGES_DRAINED} &&
$tracepoint ne "mm_page_pcpu_drain") {
$perprocesspid{$process_pid}->{HIGH_PCPU_DRAINS}++;
$perprocesspid{$process_pid}->{STATE_PCPU_PAGES_DRAINED} = 0;
}
# Catch a full pcpu refill event
if ($perprocesspid{$process_pid}->{STATE_PCPU_PAGES_REFILLED} &&
$tracepoint ne "mm_page_alloc_zone_locked") {
$perprocesspid{$process_pid}->{HIGH_PCPU_REFILLS}++;
$perprocesspid{$process_pid}->{STATE_PCPU_PAGES_REFILLED} = 0;
}
if ($sigint_pending) {
last EVENT_PROCESS;
}
}
}
sub dump_stats {
my $hashref = shift;
my %stats = %$hashref;
# Dump per-process stats
my $process_pid;
my $max_strlen = 0;
# Get the maximum process name
foreach $process_pid (keys %perprocesspid) {
my $len = length($process_pid);
if ($len > $max_strlen) {
$max_strlen = $len;
}
}
$max_strlen += 2;
printf("\n");
printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s\n",
"Process", "Pages", "Pages", "Pages", "Pages", "PCPU", "PCPU", "PCPU", "Fragment", "Fragment", "MigType", "Fragment", "Fragment", "Unknown");
printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s\n",
"details", "allocd", "allocd", "freed", "freed", "pages", "drains", "refills", "Fallback", "Causing", "Changed", "Severe", "Moderate", "");
printf("%-" . $max_strlen . "s %8s %10s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s %8s\n",
"", "", "under lock", "direct", "pagevec", "drain", "", "", "", "", "", "", "", "");
foreach $process_pid (keys %stats) {
# Dump final aggregates
if ($stats{$process_pid}->{STATE_PCPU_PAGES_DRAINED}) {
$stats{$process_pid}->{HIGH_PCPU_DRAINS}++;
$stats{$process_pid}->{STATE_PCPU_PAGES_DRAINED} = 0;
}
if ($stats{$process_pid}->{STATE_PCPU_PAGES_REFILLED}) {
$stats{$process_pid}->{HIGH_PCPU_REFILLS}++;
$stats{$process_pid}->{STATE_PCPU_PAGES_REFILLED} = 0;
}
printf("%-" . $max_strlen . "s %8d %10d %8d %8d %8d %8d %8d %8d %8d %8d %8d %8d %8d\n",
$process_pid,
$stats{$process_pid}->{MM_PAGE_ALLOC},
$stats{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED},
$stats{$process_pid}->{MM_PAGE_FREE},
$stats{$process_pid}->{MM_PAGE_FREE_BATCHED},
$stats{$process_pid}->{MM_PAGE_PCPU_DRAIN},
$stats{$process_pid}->{HIGH_PCPU_DRAINS},
$stats{$process_pid}->{HIGH_PCPU_REFILLS},
$stats{$process_pid}->{MM_PAGE_ALLOC_EXTFRAG},
$stats{$process_pid}->{HIGH_EXT_FRAG},
$stats{$process_pid}->{HIGH_EXT_FRAGMENT_CHANGED},
$stats{$process_pid}->{HIGH_EXT_FRAGMENT_SEVERE},
$stats{$process_pid}->{HIGH_EXT_FRAGMENT_MODERATE},
$stats{$process_pid}->{EVENT_UNKNOWN});
}
}
sub aggregate_perprocesspid() {
my $process_pid;
my $process;
undef %perprocess;
foreach $process_pid (keys %perprocesspid) {
$process = $process_pid;
$process =~ s/-([0-9])*$//;
if ($process eq '') {
$process = "NO_PROCESS_NAME";
}
$perprocess{$process}->{MM_PAGE_ALLOC} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC};
$perprocess{$process}->{MM_PAGE_ALLOC_ZONE_LOCKED} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED};
$perprocess{$process}->{MM_PAGE_FREE} += $perprocesspid{$process_pid}->{MM_PAGE_FREE};
$perprocess{$process}->{MM_PAGE_FREE_BATCHED} += $perprocesspid{$process_pid}->{MM_PAGE_FREE_BATCHED};
$perprocess{$process}->{MM_PAGE_PCPU_DRAIN} += $perprocesspid{$process_pid}->{MM_PAGE_PCPU_DRAIN};
$perprocess{$process}->{HIGH_PCPU_DRAINS} += $perprocesspid{$process_pid}->{HIGH_PCPU_DRAINS};
$perprocess{$process}->{HIGH_PCPU_REFILLS} += $perprocesspid{$process_pid}->{HIGH_PCPU_REFILLS};
$perprocess{$process}->{MM_PAGE_ALLOC_EXTFRAG} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC_EXTFRAG};
$perprocess{$process}->{HIGH_EXT_FRAG} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAG};
$perprocess{$process}->{HIGH_EXT_FRAGMENT_CHANGED} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_CHANGED};
$perprocess{$process}->{HIGH_EXT_FRAGMENT_SEVERE} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_SEVERE};
$perprocess{$process}->{HIGH_EXT_FRAGMENT_MODERATE} += $perprocesspid{$process_pid}->{HIGH_EXT_FRAGMENT_MODERATE};
$perprocess{$process}->{EVENT_UNKNOWN} += $perprocesspid{$process_pid}->{EVENT_UNKNOWN};
}
}
sub report() {
if (!$opt_ignorepid) {
dump_stats(\%perprocesspid);
} else {
aggregate_perprocesspid();
dump_stats(\%perprocess);
}
}
# Process events or signals until neither is available
sub signal_loop() {
my $sigint_processed;
do {
$sigint_processed = 0;
process_events();
# Handle pending signals if any
if ($sigint_pending) {
my $current_time = time;
if ($sigint_exit) {
print "Received exit signal\n";
$sigint_pending = 0;
}
if ($sigint_report) {
if ($current_time >= $sigint_received + 2) {
report();
$sigint_report = 0;
$sigint_pending = 0;
$sigint_processed = 1;
}
}
}
} while ($sigint_pending || $sigint_processed);
}
signal_loop();
report();