[PATCHv4] perf kvm: add kvm-stat for arm64

* [PATCHv4] perf kvm: add kvm-stat for arm64
@ 2020-09-17 10:02 Sergey Senozhatsky
  2020-09-29  3:34 ` Sergey Senozhatsky
  0 siblings, 1 reply; 5+ messages in thread
From: Sergey Senozhatsky @ 2020-09-17 10:02 UTC (permalink / raw)
  To: Leo Yan, Arnaldo Carvalho de Melo, Mark Rutland, Peter Zijlstra,
	Will Deacon
  Cc: John Garry, Mathieu Poirier, Namhyung Kim, Suleiman Souhlal,
	linux-kernel, linux-arm-kernel, Sergey Senozhatsky

Add support for perf kvm stat on arm64 platform.

Example:
 # perf kvm stat report

Analyze events for all VMs, all VCPUs:

    VM-EXIT    Samples  Samples%     Time%    Min Time    Max Time         Avg time

   DABT_LOW     661867    98.91%    40.45%      2.19us   3364.65us      6.24us ( +-   0.34% )
        IRQ       4598     0.69%    57.44%      2.89us   3397.59us   1276.27us ( +-   1.61% )
        WFx       1475     0.22%     1.71%      2.22us   3388.63us    118.31us ( +-   8.69% )
   IABT_LOW       1018     0.15%     0.38%      2.22us   2742.07us     38.29us ( +-  12.55% )
      SYS64        180     0.03%     0.01%      2.07us    112.91us      6.57us ( +-  14.95% )
      HVC64         17     0.00%     0.01%      2.19us    322.35us     42.95us ( +-  58.98% )

Total Samples:669155, Total events handled time:10216387.86us.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>

---

v4: rebased (Leo)
v3: report ARM_EXCEPTION_IL exceptions (Leo)
v2: reworked the patch after offline discussion with Suleiman

 tools/perf/arch/arm64/Makefile                |  1 +
 tools/perf/arch/arm64/util/Build              |  1 +
 .../arch/arm64/util/arm64_exception_types.h   | 92 +++++++++++++++++++
 tools/perf/arch/arm64/util/kvm-stat.c         | 85 +++++++++++++++++
 4 files changed, 179 insertions(+)
 create mode 100644 tools/perf/arch/arm64/util/arm64_exception_types.h
 create mode 100644 tools/perf/arch/arm64/util/kvm-stat.c

diff --git a/tools/perf/arch/arm64/Makefile b/tools/perf/arch/arm64/Makefile
index dbef716a1913..fab3095fb5d0 100644
--- a/tools/perf/arch/arm64/Makefile
+++ b/tools/perf/arch/arm64/Makefile
@@ -4,6 +4,7 @@ PERF_HAVE_DWARF_REGS := 1
 endif
 PERF_HAVE_JITDUMP := 1
 PERF_HAVE_ARCH_REGS_QUERY_REGISTER_OFFSET := 1
+HAVE_KVM_STAT_SUPPORT := 1
 
 #
 # Syscall table generation for perf
diff --git a/tools/perf/arch/arm64/util/Build b/tools/perf/arch/arm64/util/Build
index 5c13438c7bd4..4cba12f4b741 100644
--- a/tools/perf/arch/arm64/util/Build
+++ b/tools/perf/arch/arm64/util/Build
@@ -1,6 +1,7 @@
 perf-y += header.o
 perf-y += machine.o
 perf-y += perf_regs.o
+perf-y += kvm-stat.o
 perf-$(CONFIG_DWARF)     += dwarf-regs.o
 perf-$(CONFIG_LOCAL_LIBUNWIND) += unwind-libunwind.o
 perf-$(CONFIG_LIBDW_DWARF_UNWIND) += unwind-libdw.o
diff --git a/tools/perf/arch/arm64/util/arm64_exception_types.h b/tools/perf/arch/arm64/util/arm64_exception_types.h
new file mode 100644
index 000000000000..27c981ebe401
--- /dev/null
+++ b/tools/perf/arch/arm64/util/arm64_exception_types.h
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef ARCH_PERF_ARM64_EXCEPTION_TYPES_H
+#define ARCH_PERF_ARM64_EXCEPTION_TYPES_H
+
+/* Per asm/virt.h */
+#define HVC_STUB_ERR		  0xbadca11
+
+/* Per asm/kvm_asm.h */
+#define ARM_EXCEPTION_IRQ		0
+#define ARM_EXCEPTION_EL1_SERROR	1
+#define ARM_EXCEPTION_TRAP		2
+#define ARM_EXCEPTION_IL		3
+/* The hyp-stub will return this for any kvm_call_hyp() call */
+#define ARM_EXCEPTION_HYP_GONE		HVC_STUB_ERR
+
+#define kvm_arm_exception_type					\
+	{ARM_EXCEPTION_IRQ,		"IRQ"		},	\
+	{ARM_EXCEPTION_EL1_SERROR,	"SERROR"	},	\
+	{ARM_EXCEPTION_TRAP,		"TRAP"		},	\
+	{ARM_EXCEPTION_IL,		"ILLEGAL"	},	\
+	{ARM_EXCEPTION_HYP_GONE,	"HYP_GONE"	}
+
+/* Per asm/esr.h */
+#define ESR_ELx_EC_UNKNOWN	(0x00)
+#define ESR_ELx_EC_WFx		(0x01)
+/* Unallocated EC: 0x02 */
+#define ESR_ELx_EC_CP15_32	(0x03)
+#define ESR_ELx_EC_CP15_64	(0x04)
+#define ESR_ELx_EC_CP14_MR	(0x05)
+#define ESR_ELx_EC_CP14_LS	(0x06)
+#define ESR_ELx_EC_FP_ASIMD	(0x07)
+#define ESR_ELx_EC_CP10_ID	(0x08)	/* EL2 only */
+#define ESR_ELx_EC_PAC		(0x09)	/* EL2 and above */
+/* Unallocated EC: 0x0A - 0x0B */
+#define ESR_ELx_EC_CP14_64	(0x0C)
+/* Unallocated EC: 0x0d */
+#define ESR_ELx_EC_ILL		(0x0E)
+/* Unallocated EC: 0x0F - 0x10 */
+#define ESR_ELx_EC_SVC32	(0x11)
+#define ESR_ELx_EC_HVC32	(0x12)	/* EL2 only */
+#define ESR_ELx_EC_SMC32	(0x13)	/* EL2 and above */
+/* Unallocated EC: 0x14 */
+#define ESR_ELx_EC_SVC64	(0x15)
+#define ESR_ELx_EC_HVC64	(0x16)	/* EL2 and above */
+#define ESR_ELx_EC_SMC64	(0x17)	/* EL2 and above */
+#define ESR_ELx_EC_SYS64	(0x18)
+#define ESR_ELx_EC_SVE		(0x19)
+#define ESR_ELx_EC_ERET		(0x1a)	/* EL2 only */
+/* Unallocated EC: 0x1b - 0x1E */
+#define ESR_ELx_EC_IMP_DEF	(0x1f)	/* EL3 only */
+#define ESR_ELx_EC_IABT_LOW	(0x20)
+#define ESR_ELx_EC_IABT_CUR	(0x21)
+#define ESR_ELx_EC_PC_ALIGN	(0x22)
+/* Unallocated EC: 0x23 */
+#define ESR_ELx_EC_DABT_LOW	(0x24)
+#define ESR_ELx_EC_DABT_CUR	(0x25)
+#define ESR_ELx_EC_SP_ALIGN	(0x26)
+/* Unallocated EC: 0x27 */
+#define ESR_ELx_EC_FP_EXC32	(0x28)
+/* Unallocated EC: 0x29 - 0x2B */
+#define ESR_ELx_EC_FP_EXC64	(0x2C)
+/* Unallocated EC: 0x2D - 0x2E */
+#define ESR_ELx_EC_SERROR	(0x2F)
+#define ESR_ELx_EC_BREAKPT_LOW	(0x30)
+#define ESR_ELx_EC_BREAKPT_CUR	(0x31)
+#define ESR_ELx_EC_SOFTSTP_LOW	(0x32)
+#define ESR_ELx_EC_SOFTSTP_CUR	(0x33)
+#define ESR_ELx_EC_WATCHPT_LOW	(0x34)
+#define ESR_ELx_EC_WATCHPT_CUR	(0x35)
+/* Unallocated EC: 0x36 - 0x37 */
+#define ESR_ELx_EC_BKPT32	(0x38)
+/* Unallocated EC: 0x39 */
+#define ESR_ELx_EC_VECTOR32	(0x3A)	/* EL2 only */
+/* Unallocated EC: 0x3B */
+#define ESR_ELx_EC_BRK64	(0x3C)
+/* Unallocated EC: 0x3D - 0x3F */
+#define ESR_ELx_EC_MAX		(0x3F)
+
+#define ECN(x) { ESR_ELx_EC_##x, #x }
+
+#define kvm_arm_exception_class \
+	ECN(UNKNOWN), ECN(WFx), ECN(CP15_32), ECN(CP15_64), ECN(CP14_MR), \
+	ECN(CP14_LS), ECN(FP_ASIMD), ECN(CP10_ID), ECN(PAC), ECN(CP14_64), \
+	ECN(SVC64), ECN(HVC64), ECN(SMC64), ECN(SYS64), ECN(SVE), \
+	ECN(IMP_DEF), ECN(IABT_LOW), ECN(IABT_CUR), \
+	ECN(PC_ALIGN), ECN(DABT_LOW), ECN(DABT_CUR), \
+	ECN(SP_ALIGN), ECN(FP_EXC32), ECN(FP_EXC64), ECN(SERROR), \
+	ECN(BREAKPT_LOW), ECN(BREAKPT_CUR), ECN(SOFTSTP_LOW), \
+	ECN(SOFTSTP_CUR), ECN(WATCHPT_LOW), ECN(WATCHPT_CUR), \
+	ECN(BKPT32), ECN(VECTOR32), ECN(BRK64)
+
+#endif /* ARCH_PERF_ARM64_EXCEPTION_TYPES_H */
diff --git a/tools/perf/arch/arm64/util/kvm-stat.c b/tools/perf/arch/arm64/util/kvm-stat.c
new file mode 100644
index 000000000000..50376b9062c1
--- /dev/null
+++ b/tools/perf/arch/arm64/util/kvm-stat.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <errno.h>
+#include <memory.h>
+#include "../../util/evsel.h"
+#include "../../util/kvm-stat.h"
+#include "arm64_exception_types.h"
+#include "debug.h"
+
+define_exit_reasons_table(arm64_exit_reasons, kvm_arm_exception_type);
+define_exit_reasons_table(arm64_trap_exit_reasons, kvm_arm_exception_class);
+
+const char *kvm_trap_exit_reason = "esr_ec";
+const char *vcpu_id_str = "id";
+const int decode_str_len = 20;
+const char *kvm_exit_reason = "ret";
+const char *kvm_entry_trace = "kvm:kvm_entry";
+const char *kvm_exit_trace = "kvm:kvm_exit";
+
+const char *kvm_events_tp[] = {
+	"kvm:kvm_entry",
+	"kvm:kvm_exit",
+	NULL,
+};
+
+static void event_get_key(struct evsel *evsel,
+			  struct perf_sample *sample,
+			  struct event_key *key)
+{
+	key->info = 0;
+	key->key = evsel__intval(evsel, sample, kvm_exit_reason);
+	key->exit_reasons = arm64_exit_reasons;
+
+	/*
+	 * TRAP exceptions carry exception class info in esr_ec field
+	 * and, hence, we need to use a different exit_reasons table to
+	 * properly decode event's est_ec.
+	 */
+	if (key->key == ARM_EXCEPTION_TRAP) {
+		key->key = evsel__intval(evsel, sample, kvm_trap_exit_reason);
+		key->exit_reasons = arm64_trap_exit_reasons;
+	}
+}
+
+static bool event_begin(struct evsel *evsel,
+			struct perf_sample *sample __maybe_unused,
+			struct event_key *key __maybe_unused)
+{
+	return !strcmp(evsel->name, kvm_entry_trace);
+}
+
+static bool event_end(struct evsel *evsel,
+		      struct perf_sample *sample,
+		      struct event_key *key)
+{
+	if (!strcmp(evsel->name, kvm_exit_trace)) {
+		event_get_key(evsel, sample, key);
+		return true;
+	}
+	return false;
+}
+
+static struct kvm_events_ops exit_events = {
+	.is_begin_event = event_begin,
+	.is_end_event	= event_end,
+	.decode_key	= exit_event_decode_key,
+	.name		= "VM-EXIT"
+};
+
+struct kvm_reg_events_ops kvm_reg_events_ops[] = {
+	{
+		.name	= "vmexit",
+		.ops	= &exit_events,
+	},
+	{ NULL },
+};
+
+const char * const kvm_skip_events[] = {
+	NULL,
+};
+
+int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid __maybe_unused)
+{
+	kvm->exit_reasons_isa = "arm64";
+	return 0;
+}
-- 
2.28.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread