[RFC PATCH 2/2] tools: Add a tool for merging trace data of a guest and a host

Yoshihiro YUNOMAE
2012-11-14T01:37:26Z

This tool merges trace data of a guest and a host in chronological order.
Note that this tool is used only for a guest and a host. (not for multiple
guests)

- How to use
1. Get trace data of the host and guest via ssh, virtio-serial, or virtio-trace

2. Get TSC offset after applied patch "kvm/vmx: Print TSC_OFFSET information
when TSC offset value is written to VMCS"
$ dmesg | grep kvm
[ 57.717180] kvm: ([PID]) write TSC offset [TSC offset], now clock [HOST TSC]

3. Use this tool
$ ./trace-merge.pl <TSC offset> <host data> <guest data>

h qemu-kvm-2687 [003] d...50550079203669: kvm_exit: [detail]
h qemu-kvm-2687 [003] d...50550079206816: kvm_entry: [detail]
g comm-3826 [000] d.h.50550079226331: sched_wakeup: [detail]
h qemu-kvm-2687 [003] d...50550079240656: kvm_exit: [detail]
h qemu-kvm-2687 [003] d...50550079243467: kvm_entry: [detail]
h qemu-kvm-2687 [003] d...50550079256103: kvm_exit: [detail]
h qemu-kvm-2687 [003] d...50550079268391: kvm_entry: [detail]
g comm-3826 [000] d...50550079279266: sched_switch: [detail]
h qemu-kvm-2687 [003] d...50550079280829: kvm_exit: [detail]
h qemu-kvm-2687 [003] d...50550079286028: kvm_entry: [detail]
|
\----guest/host

Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
---
tools/scripts/trace-merge/trace-merge.pl | 109 ++++++++++++++++++++++++++++++
1 file changed, 109 insertions(+)
create mode 100755 tools/scripts/trace-merge/trace-merge.pl

diff --git a/tools/scripts/trace-merge/trace-merge.pl b/tools/scripts/trace-merge/trace-merge.pl
new file mode 100755
index 0000000..e0b080c
--- /dev/null
+++ b/tools/scripts/trace-merge/trace-merge.pl
@@ -0,0 +1,109 @@
+#!/usr/bin/perl
+#
+# Tool for merging and sorting trace data of a guest and host
+#
+# Created by Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com>
+#
+# - How to use
+# ./trace-merge.pl <TSC offset> <host data> <guest data>
+#
+use strict;
+use bigint;
+
+my %all_data_info = ();
+my @merged_data = ();
+my @sorted_data = ();
+
+&read_all_data();
+&merge_guest_host_data();
+&sort_data_by_tsc();
+&output_data();
+
+sub read_all_data {
+ # TSC offset value is very big ull value.
+ # This value is actually negative, so we calculate the value here.
+ $all_data_info{"tsc_offset"} = &convert_tscoffset($ARGV[0]);
+ if ($all_data_info{"tsc_offset"} == 0) {
+ die "TSC should not be 0";
+ }
+
+ if (!open(HOST_DATA, $ARGV[1])) {
+ die "Cannot open host file: $!"
+ }
+ my @host_data = <HOST_DATA>;
+ close(HOST_DATA);
+
+ if (!open(GUEST_DATA, $ARGV[2])) {
+ die "Cannot open guest file: $!"
+ }
+ my @guest_data = <GUEST_DATA>;
+ close(GUEST_DATA);
+
+ $all_data_info{"host_data"} = \@host_data;
+ $all_data_info{"guest_data"} = \@guest_data;
+}
+
+sub merge_guest_host_data {
+ &guest_push_data();
+ &host_push_data();
+}
+
+sub sort_data_by_tsc {
+ no strict 'refs';
+ @sorted_data = sort {$a->{tsc} <=> $b->{tsc}} @merged_data;
+}
+
+sub output_data {
+ foreach my $line (@sorted_data) {
+ print "$line->{name}$line->{comm}$line->{tsc}$line->{event}\n";
+ }
+}
+
+sub guest_push_data {
+ &make_data_list(1);
+}
+
+sub host_push_data {
+ &make_data_list(0);
+}
+
+#
+# If this function is used for guest's data,
+# subtract TSC offset from guest's TSC value.
+#
+# NOTE: guest's TSC is added TSC offset to actual TSC when the guest boots.
+#
+sub make_data_list {
+ my $is_guest = $_[0];
+ my @data = ();
+ my $name = "";
+ my $list = "";
+ my $tsc_offset = 0;
+
+ if ($is_guest eq 1) {
+ $name = "g";
+ @data = @{$all_data_info{"guest_data"}};
+ $tsc_offset = $all_data_info{"tsc_offset"};
+ } else {
+ $name = "h";
+ @data = @{$all_data_info{"host_data"}};
+ }
+
+ foreach my $line (@data) {
+ chomp($line);
+
+ if ($line =~ /^(.+\[[0-9]+\].{5})([0-9]+)(:.+)/) {
+ $list = {
+ name => $name,
+ comm => $1,
+ tsc => $2 - $tsc_offset,
+ event => $3
+ };
+ push(@merged_data, $list);
+ }
+ }
+}
+
+sub convert_tscoffset {
+ return $_[0] - (1 << 64);
+}