perf kvm: Use defines of kvm events

Currently perf-kvm uses string literals for kvm event names, but it
works only for x86, because other architectures may have other names for
those events.

To reduce dependence on architecture, we add <asm/kvm_perf.h> file with
defines for:

- kvm_entry and kvm_exit events,
- exit reason field name in kvm_exit event,
- length of exit reasons strings,
- vcpu_id field name in kvm trace events,

and replace literals in perf-kvm.

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1404397747-20939-2-git-send-email-yarygin@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

arch/x86/include/uapi/asm/Kbuild

@@ -22,6 +22,7 @@ header-y += ipcbuf.h
 header-y += ist.h
 header-y += kvm.h
 header-y += kvm_para.h
+header-y += kvm_perf.h
 header-y += ldt.h
 header-y += mce.h
 header-y += mman.h

arch/x86/include/uapi/asm/kvm_perf.h

@@ -0,0 +1,16 @@
+#ifndef _ASM_X86_KVM_PERF_H
+#define _ASM_X86_KVM_PERF_H
+
+#include <asm/svm.h>
+#include <asm/vmx.h>
+#include <asm/kvm.h>
+
+#define DECODE_STR_LEN 20
+
+#define VCPU_ID "vcpu_id"
+
+#define KVM_ENTRY_TRACE "kvm:kvm_entry"
+#define KVM_EXIT_TRACE "kvm:kvm_exit"
+#define KVM_EXIT_REASON "exit_reason"
+
+#endif /* _ASM_X86_KVM_PERF_H */

tools/perf/MANIFEST

@@ -37,3 +37,4 @@ arch/x86/include/asm/kvm_host.h
 arch/x86/include/uapi/asm/svm.h
 arch/x86/include/uapi/asm/vmx.h
 arch/x86/include/uapi/asm/kvm.h
+arch/x86/include/uapi/asm/kvm_perf.h

tools/perf/builtin-kvm.c

@@ -30,9 +30,7 @@
 #include <math.h>
 
 #ifdef HAVE_KVM_STAT_SUPPORT
-#include <asm/svm.h>
-#include <asm/vmx.h>
-#include <asm/kvm.h>
+#include <asm/kvm_perf.h>
 
 struct event_key {
 	#define INVALID_KEY     (~0ULL)
@@ -75,7 +73,7 @@ struct kvm_events_ops {
 	bool (*is_end_event)(struct perf_evsel *evsel,
 			     struct perf_sample *sample, struct event_key *key);
 	void (*decode_key)(struct perf_kvm_stat *kvm, struct event_key *key,
-			   char decode[20]);
+			   char *decode);
 	const char *name;
 };
 
@@ -126,12 +124,12 @@ static void exit_event_get_key(struct perf_evsel *evsel,
 			       struct event_key *key)
 {
 	key->info = 0;
-	key->key = perf_evsel__intval(evsel, sample, "exit_reason");
+	key->key = perf_evsel__intval(evsel, sample, KVM_EXIT_REASON);
 }
 
 static bool kvm_exit_event(struct perf_evsel *evsel)
 {
-	return !strcmp(evsel->name, "kvm:kvm_exit");
+	return !strcmp(evsel->name, KVM_EXIT_TRACE);
 }
 
 static bool exit_event_begin(struct perf_evsel *evsel,
@@ -147,7 +145,7 @@ static bool exit_event_begin(struct perf_evsel *evsel,
 
 static bool kvm_entry_event(struct perf_evsel *evsel)
 {
-	return !strcmp(evsel->name, "kvm:kvm_entry");
+	return !strcmp(evsel->name, KVM_ENTRY_TRACE);
 }
 
 static bool exit_event_end(struct perf_evsel *evsel,
@@ -182,12 +180,12 @@ static const char *get_exit_reason(struct perf_kvm_stat *kvm,
 
 static void exit_event_decode_key(struct perf_kvm_stat *kvm,
 				  struct event_key *key,
-				  char decode[20])
+				  char *decode)
 {
 	const char *exit_reason = get_exit_reason(kvm, kvm->exit_reasons,
 						  key->key);
 
-	scnprintf(decode, 20, "%s", exit_reason);
+	scnprintf(decode, DECODE_STR_LEN, "%s", exit_reason);
 }
 
 static struct kvm_events_ops exit_events = {
@@ -249,9 +247,9 @@ static bool mmio_event_end(struct perf_evsel *evsel, struct perf_sample *sample,
 
 static void mmio_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
 				  struct event_key *key,
-				  char decode[20])
+				  char *decode)
 {
-	scnprintf(decode, 20, "%#lx:%s", (unsigned long)key->key,
+	scnprintf(decode, DECODE_STR_LEN, "%#lx:%s", (unsigned long)key->key,
 				key->info == KVM_TRACE_MMIO_WRITE ? "W" : "R");
 }
 
@@ -292,9 +290,9 @@ static bool ioport_event_end(struct perf_evsel *evsel,
 
 static void ioport_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
 				    struct event_key *key,
-				    char decode[20])
+				    char *decode)
 {
-	scnprintf(decode, 20, "%#llx:%s", (unsigned long long)key->key,
+	scnprintf(decode, DECODE_STR_LEN, "%#llx:%s", (unsigned long long)key->key,
 				key->info ? "POUT" : "PIN");
 }
 
@@ -524,7 +522,7 @@ static bool handle_end_event(struct perf_kvm_stat *kvm,
 	time_diff = sample->time - time_begin;
 
 	if (kvm->duration && time_diff > kvm->duration) {
-		char decode[32];
+		char decode[DECODE_STR_LEN];
 
 		kvm->events_ops->decode_key(kvm, &event->key, decode);
 		if (strcmp(decode, "HLT")) {
@@ -552,7 +550,7 @@ struct vcpu_event_record *per_vcpu_record(struct thread *thread,
 			return NULL;
 		}
 
-		vcpu_record->vcpu_id = perf_evsel__intval(evsel, sample, "vcpu_id");
+		vcpu_record->vcpu_id = perf_evsel__intval(evsel, sample, VCPU_ID);
 		thread->priv = vcpu_record;
 	}
 
@@ -739,7 +737,7 @@ static void show_timeofday(void)
 
 static void print_result(struct perf_kvm_stat *kvm)
 {
-	char decode[20];
+	char decode[DECODE_STR_LEN];
 	struct kvm_event *event;
 	int vcpu = kvm->trace_vcpu;
 
@@ -750,7 +748,7 @@ static void print_result(struct perf_kvm_stat *kvm)
 
 	pr_info("\n\n");
 	print_vcpu_info(kvm);
-	pr_info("%20s ", kvm->events_ops->name);
+	pr_info("%*s ", DECODE_STR_LEN, kvm->events_ops->name);
 	pr_info("%10s ", "Samples");
 	pr_info("%9s ", "Samples%");
 
@@ -769,7 +767,7 @@ static void print_result(struct perf_kvm_stat *kvm)
 		min = get_event_min(event, vcpu);
 
 		kvm->events_ops->decode_key(kvm, &event->key, decode);
-		pr_info("%20s ", decode);
+		pr_info("%*s ", DECODE_STR_LEN, decode);
 		pr_info("%10llu ", (unsigned long long)ecount);
 		pr_info("%8.2f%% ", (double)ecount / kvm->total_count * 100);
 		pr_info("%8.2f%% ", (double)etime / kvm->total_time * 100);