[PATCH 0/3] trace-cmd: Updates for kvm plugin

[Jan Kiszka]

Patch 1 is resent unchanged from a previous round, patches 2 and 3
improve the output of nested vmexit tracepoints.

Jan Kiszka (3):
trace-cmd: Report unknown VMX exit reasons with code
trace-cmd: Factor out print_exit_reason in kvm plugin
trace-cmd: Fix and cleanup kvm_nested_vmexit tracepoints

plugin_kvm.c | 47 +++++++++++++++++++++++++++--------------------
1 file changed, 27 insertions(+), 20 deletions(-)

[Jan Kiszka]

From: Jan Kiszka <***@siemens.com>

Allows to parse the result even if the KVM plugin does not yet
understand a specific exit code.

Signed-off-by: Jan Kiszka <***@siemens.com>
---
plugin_kvm.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/plugin_kvm.c b/plugin_kvm.c
index 8a25cf1..59443e5 100644
--- a/plugin_kvm.c
+++ b/plugin_kvm.c
@@ -240,9 +240,8 @@ static const char *find_exit_reason(unsigned isa, int val)
for (i = 0; strings[i].val >= 0; i++)
if (strings[i].val == val)
break;
- if (strings[i].str)
- return strings[i].str;
- return "UNKNOWN";
+
+ return strings[i].str;
}

static int kvm_exit_handler(struct trace_seq *s, struct pevent_record *record,
@@ -251,6 +250,7 @@ static int kvm_exit_handler(struct trace_seq *s, struct pevent_record *record,
unsigned long long isa;
unsigned long long val;
unsigned long long info1 = 0, info2 = 0;
+ const char *reason;

if (pevent_get_field_val(s, event, "exit_reason", record, &val, 1) < 0)
return -1;
@@ -258,7 +258,11 @@ static int kvm_exit_handler(struct trace_seq *s, struct pevent_record *record,
if (pevent_get_field_val(s, event, "isa", record, &isa, 0) < 0)
isa = 1;

- trace_seq_printf(s, "reason %s", find_exit_reason(isa, val));
+ reason = find_exit_reason(isa, val);
+ if (reason)
+ trace_seq_printf(s, "reason %s", reason);
+ else
+ trace_seq_printf(s, "reason UNKNOWN (%llu)", val);

pevent_print_num_field(s, " rip 0x%lx", event, "guest_rip", record, 1);

[Jan Kiszka]

From: Jan Kiszka <***@siemens.com>

We will reuse it for nested vmexit tracepoints.

Signed-off-by: Jan Kiszka <***@siemens.com>
---
plugin_kvm.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/plugin_kvm.c b/plugin_kvm.c
index 59443e5..c407e55 100644
--- a/plugin_kvm.c
+++ b/plugin_kvm.c
@@ -244,15 +244,14 @@ static const char *find_exit_reason(unsigned isa, int val)
return strings[i].str;
}

-static int kvm_exit_handler(struct trace_seq *s, struct pevent_record *record,
- struct event_format *event, void *context)
+static int print_exit_reason(struct trace_seq *s, struct pevent_record *record,
+ struct event_format *event, const char *field)
{
unsigned long long isa;
unsigned long long val;
- unsigned long long info1 = 0, info2 = 0;
const char *reason;

- if (pevent_get_field_val(s, event, "exit_reason", record, &val, 1) < 0)
+ if (pevent_get_field_val(s, event, field, record, &val, 1) < 0)
return -1;

if (pevent_get_field_val(s, event, "isa", record, &isa, 0) < 0)
@@ -263,6 +262,16 @@ static int kvm_exit_handler(struct trace_seq *s, struct pevent_record *record,
trace_seq_printf(s, "reason %s", reason);
else
trace_seq_printf(s, "reason UNKNOWN (%llu)", val);
+ return 0;
+}
+
+static int kvm_exit_handler(struct trace_seq *s, struct pevent_record *record,
+ struct event_format *event, void *context)
+{
+ unsigned long long info1 = 0, info2 = 0;
+
+ if (print_exit_reason(s, record, event, "exit_reason") < 0)
+ return -1;

pevent_print_num_field(s, " rip 0x%lx", event, "guest_rip", record, 1);

[Jan Kiszka]

From: Jan Kiszka <***@siemens.com>

Fix several issues of kvm_nested_vmexit[_inject]: field width aren't
supported with pevent_print, rip was printed twice/incorrectly, SVM ISA
was hard-coded, we don't use ':' to separate field names.

Signed-off-by: Jan Kiszka <***@siemens.com>
---
plugin_kvm.c | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)

diff --git a/plugin_kvm.c b/plugin_kvm.c
index c407e55..cb52e9e 100644
--- a/plugin_kvm.c
+++ b/plugin_kvm.c
@@ -330,19 +330,13 @@ static int kvm_emulate_insn_handler(struct trace_seq *s, struct pevent_record *r
static int kvm_nested_vmexit_inject_handler(struct trace_seq *s, struct pevent_record *record,
struct event_format *event, void *context)
{
- unsigned long long val;
-
- pevent_print_num_field(s, " rip %0x016llx", event, "rip", record, 1);
-
- if (pevent_get_field_val(s, event, "exit_code", record, &val, 1) < 0)
+ if (print_exit_reason(s, record, event, "exit_code") < 0)
return -1;

- trace_seq_printf(s, "reason %s", find_exit_reason(2, val));
-
- pevent_print_num_field(s, " ext_inf1: %0x016llx", event, "exit_info1", record, 1);
- pevent_print_num_field(s, " ext_inf2: %0x016llx", event, "exit_info2", record, 1);
- pevent_print_num_field(s, " ext_int: %0x016llx", event, "exit_int_info", record, 1);
- pevent_print_num_field(s, " ext_int_err: %0x016llx", event, "exit_int_info_err", record, 1);
+ pevent_print_num_field(s, " info1 %llx", event, "exit_info1", record, 1);
+ pevent_print_num_field(s, " info2 %llx", event, "exit_info2", record, 1);
+ pevent_print_num_field(s, " int_info %llx", event, "exit_int_info", record, 1);
+ pevent_print_num_field(s, " int_info_err %llx", event, "exit_int_info_err", record, 1);

return 0;
}
@@ -350,7 +344,7 @@ static int kvm_nested_vmexit_inject_handler(struct trace_seq *s, struct pevent_r
static int kvm_nested_vmexit_handler(struct trace_seq *s, struct pevent_record *record,
struct event_format *event, void *context)
{
- pevent_print_num_field(s, " rip %0x016llx", event, "rip", record, 1);
+ pevent_print_num_field(s, "rip %lx ", event, "rip", record, 1);

return kvm_nested_vmexit_inject_handler(s, record, event, context);
}