[PATCH v11 4/4] perf,kvm/powerpc: Add support for HCALL reasons

From: Hemant Kumar
Date: Thu Jan 28 2016 - 01:34:32 EST


Powerpc provides hcall events that also provides insights into guest
behaviour. Enhance perf kvm stat to record and analyze hcall events.

- To trace hcall events :
perf kvm stat record

- To show the results :
perf kvm stat report --event=hcall

The result shows the number of hypervisor calls from the guest grouped
by their respective reasons displayed with the frequency.

This patch makes use of two additional tracepoints
"kvm_hv:kvm_hcall_enter" and "kvm_hv:kvm_hcall_exit". To map the hcall
codes to their respective names, it needs a mapping. Such mapping is
added in this patch in book3s_hcalls.h.

# pgrep qemu
A sample output :
19378
60515

2 VMs running.

# perf kvm stat record -a
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 4.153 MB perf.data.guest (39624
samples) ]

# perf kvm stat report -p 60515 --event=hcall

Analyze events for all VMs, all VCPUs:

HCALL-EVENT Samples Samples% Time% Min Time Max Time Avg time

H_IPI 822 66.08% 88.10% 0.63us 11.38us 2.05us ( +- 1.42% )
H_SEND_CRQ 144 11.58% 3.77% 0.41us 0.88us 0.50us ( +- 1.47% )
H_VIO_SIGNAL 118 9.49% 2.86% 0.37us 0.83us 0.47us ( +- 1.43% )
H_PUT_TERM_CHAR 76 6.11% 2.07% 0.37us 0.90us 0.52us ( +- 2.43% )
H_GET_TERM_CHAR 74 5.95% 2.23% 0.37us 1.70us 0.58us ( +- 4.77% )
H_RTAS 6 0.48% 0.85% 1.10us 9.25us 2.70us ( +- 48.57% )
H_PERFMON 4 0.32% 0.12% 0.41us 0.96us 0.59us ( +- 20.92% )

Total Samples:1244, Total events handled time:1916.69us.

Signed-off-by: Hemant Kumar <hemant@xxxxxxxxxxxxxxxxxx>
---
Changelog:
v9 to v11:
- No Changes.
v8 to v9:
- Removed the macros (which were being used only once).
v6 to v7:
- Removed dependency on uapi.
v4 to v5:
- Removed dependency on arch/powerpc/include/asm/hvall.h and added them
in userspace side.
- No more arch side dependency.
v1 to v2:
- Split the patches for powerpc and perf.

tools/perf/arch/powerpc/util/book3s_hcalls.h | 123 +++++++++++++++++++++++++++
tools/perf/arch/powerpc/util/kvm-stat.c | 65 +++++++++++++-
2 files changed, 187 insertions(+), 1 deletion(-)
create mode 100644 tools/perf/arch/powerpc/util/book3s_hcalls.h

diff --git a/tools/perf/arch/powerpc/util/book3s_hcalls.h b/tools/perf/arch/powerpc/util/book3s_hcalls.h
new file mode 100644
index 0000000..0dd6b7f
--- /dev/null
+++ b/tools/perf/arch/powerpc/util/book3s_hcalls.h
@@ -0,0 +1,123 @@
+#ifndef ARCH_PERF_BOOK3S_HV_HCALLS_H
+#define ARCH_PERF_BOOK3S_HV_HCALLS_H
+
+/*
+ * PowerPC HCALL codes : hcall code to name mapping
+ */
+#define kvm_trace_symbol_hcall \
+ {0x4, "H_REMOVE"}, \
+ {0x8, "H_ENTER"}, \
+ {0xc, "H_READ"}, \
+ {0x10, "H_CLEAR_MOD"}, \
+ {0x14, "H_CLEAR_REF"}, \
+ {0x18, "H_PROTECT"}, \
+ {0x1c, "H_GET_TCE"}, \
+ {0x20, "H_PUT_TCE"}, \
+ {0x24, "H_SET_SPRG0"}, \
+ {0x28, "H_SET_DABR"}, \
+ {0x2c, "H_PAGE_INIT"}, \
+ {0x30, "H_SET_ASR"}, \
+ {0x34, "H_ASR_ON"}, \
+ {0x38, "H_ASR_OFF"}, \
+ {0x3c, "H_LOGICAL_CI_LOAD"}, \
+ {0x40, "H_LOGICAL_CI_STORE"}, \
+ {0x44, "H_LOGICAL_CACHE_LOAD"}, \
+ {0x48, "H_LOGICAL_CACHE_STORE"}, \
+ {0x4c, "H_LOGICAL_ICBI"}, \
+ {0x50, "H_LOGICAL_DCBF"}, \
+ {0x54, "H_GET_TERM_CHAR"}, \
+ {0x58, "H_PUT_TERM_CHAR"}, \
+ {0x5c, "H_REAL_TO_LOGICAL"}, \
+ {0x60, "H_HYPERVISOR_DATA"}, \
+ {0x64, "H_EOI"}, \
+ {0x68, "H_CPPR"}, \
+ {0x6c, "H_IPI"}, \
+ {0x70, "H_IPOLL"}, \
+ {0x74, "H_XIRR"}, \
+ {0x78, "H_MIGRATE_DMA"}, \
+ {0x7c, "H_PERFMON"}, \
+ {0xdc, "H_REGISTER_VPA"}, \
+ {0xe0, "H_CEDE"}, \
+ {0xe4, "H_CONFER"}, \
+ {0xe8, "H_PROD"}, \
+ {0xec, "H_GET_PPP"}, \
+ {0xf0, "H_SET_PPP"}, \
+ {0xf4, "H_PURR"}, \
+ {0xf8, "H_PIC"}, \
+ {0xfc, "H_REG_CRQ"}, \
+ {0x100, "H_FREE_CRQ"}, \
+ {0x104, "H_VIO_SIGNAL"}, \
+ {0x108, "H_SEND_CRQ"}, \
+ {0x110, "H_COPY_RDMA"}, \
+ {0x114, "H_REGISTER_LOGICAL_LAN"}, \
+ {0x118, "H_FREE_LOGICAL_LAN"}, \
+ {0x11c, "H_ADD_LOGICAL_LAN_BUFFER"}, \
+ {0x120, "H_SEND_LOGICAL_LAN"}, \
+ {0x124, "H_BULK_REMOVE"}, \
+ {0x130, "H_MULTICAST_CTRL"}, \
+ {0x134, "H_SET_XDABR"}, \
+ {0x138, "H_STUFF_TCE"}, \
+ {0x13c, "H_PUT_TCE_INDIRECT"}, \
+ {0x14c, "H_CHANGE_LOGICAL_LAN_MAC"}, \
+ {0x150, "H_VTERM_PARTNER_INFO"}, \
+ {0x154, "H_REGISTER_VTERM"}, \
+ {0x158, "H_FREE_VTERM"}, \
+ {0x15c, "H_RESET_EVENTS"}, \
+ {0x160, "H_ALLOC_RESOURCE"}, \
+ {0x164, "H_FREE_RESOURCE"}, \
+ {0x168, "H_MODIFY_QP"}, \
+ {0x16c, "H_QUERY_QP"}, \
+ {0x170, "H_REREGISTER_PMR"}, \
+ {0x174, "H_REGISTER_SMR"}, \
+ {0x178, "H_QUERY_MR"}, \
+ {0x17c, "H_QUERY_MW"}, \
+ {0x180, "H_QUERY_HCA"}, \
+ {0x184, "H_QUERY_PORT"}, \
+ {0x188, "H_MODIFY_PORT"}, \
+ {0x18c, "H_DEFINE_AQP1"}, \
+ {0x190, "H_GET_TRACE_BUFFER"}, \
+ {0x194, "H_DEFINE_AQP0"}, \
+ {0x198, "H_RESIZE_MR"}, \
+ {0x19c, "H_ATTACH_MCQP"}, \
+ {0x1a0, "H_DETACH_MCQP"}, \
+ {0x1a4, "H_CREATE_RPT"}, \
+ {0x1a8, "H_REMOVE_RPT"}, \
+ {0x1ac, "H_REGISTER_RPAGES"}, \
+ {0x1b0, "H_DISABLE_AND_GETC"}, \
+ {0x1b4, "H_ERROR_DATA"}, \
+ {0x1b8, "H_GET_HCA_INFO"}, \
+ {0x1bc, "H_GET_PERF_COUNT"}, \
+ {0x1c0, "H_MANAGE_TRACE"}, \
+ {0x1d4, "H_FREE_LOGICAL_LAN_BUFFER"}, \
+ {0x1d8, "H_POLL_PENDING"}, \
+ {0x1e4, "H_QUERY_INT_STATE"}, \
+ {0x244, "H_ILLAN_ATTRIBUTES"}, \
+ {0x250, "H_MODIFY_HEA_QP"}, \
+ {0x254, "H_QUERY_HEA_QP"}, \
+ {0x258, "H_QUERY_HEA"}, \
+ {0x25c, "H_QUERY_HEA_PORT"}, \
+ {0x260, "H_MODIFY_HEA_PORT"}, \
+ {0x264, "H_REG_BCMC"}, \
+ {0x268, "H_DEREG_BCMC"}, \
+ {0x26c, "H_REGISTER_HEA_RPAGES"}, \
+ {0x270, "H_DISABLE_AND_GET_HEA"}, \
+ {0x274, "H_GET_HEA_INFO"}, \
+ {0x278, "H_ALLOC_HEA_RESOURCE"}, \
+ {0x284, "H_ADD_CONN"}, \
+ {0x288, "H_DEL_CONN"}, \
+ {0x298, "H_JOIN"}, \
+ {0x2a4, "H_VASI_STATE"}, \
+ {0x2b0, "H_ENABLE_CRQ"}, \
+ {0x2b8, "H_GET_EM_PARMS"}, \
+ {0x2d0, "H_SET_MPP"}, \
+ {0x2d4, "H_GET_MPP"}, \
+ {0x2ec, "H_HOME_NODE_ASSOCIATIVITY"}, \
+ {0x2f4, "H_BEST_ENERGY"}, \
+ {0x2fc, "H_XIRR_X"}, \
+ {0x300, "H_RANDOM"}, \
+ {0x304, "H_COP"}, \
+ {0x314, "H_GET_MPP_X"}, \
+ {0x31c, "H_SET_MODE"}, \
+ {0xf000, "H_RTAS"} \
+
+#endif
diff --git a/tools/perf/arch/powerpc/util/kvm-stat.c b/tools/perf/arch/powerpc/util/kvm-stat.c
index 27bc559..74eee30 100644
--- a/tools/perf/arch/powerpc/util/kvm-stat.c
+++ b/tools/perf/arch/powerpc/util/kvm-stat.c
@@ -1,9 +1,11 @@
#include "util/kvm-stat.h"
#include "util/parse-events.h"
+#include "util/debug.h"

#include "book3s_hv_exits.h"
+#include "book3s_hcalls.h"

-#define NR_TPS 2
+#define NR_TPS 4

const char *vcpu_id_str = "vcpu_id";
const int decode_str_len = 40;
@@ -11,17 +13,77 @@ const char *kvm_entry_trace = "kvm_hv:kvm_guest_enter";
const char *kvm_exit_trace = "kvm_hv:kvm_guest_exit";

define_exit_reasons_table(hv_exit_reasons, kvm_trace_symbol_exit);
+define_exit_reasons_table(hcall_reasons, kvm_trace_symbol_hcall);

/* Tracepoints specific to ppc_book3s_hv */
const char *ppc_book3s_hv_kvm_tp[] = {
"kvm_hv:kvm_guest_enter",
"kvm_hv:kvm_guest_exit",
+ "kvm_hv:kvm_hcall_enter",
+ "kvm_hv:kvm_hcall_exit",
+ NULL,
};

/* 1 extra placeholder for NULL */
const char *kvm_events_tp[NR_TPS + 1];
const char *kvm_exit_reason;

+static void hcall_event_get_key(struct perf_evsel *evsel,
+ struct perf_sample *sample,
+ struct event_key *key)
+{
+ key->info = 0;
+ key->key = perf_evsel__intval(evsel, sample, "req");
+}
+
+static const char *get_hcall_exit_reason(u64 exit_code)
+{
+ struct exit_reasons_table *tbl = hcall_reasons;
+
+ while (tbl->reason != NULL) {
+ if (tbl->exit_code == exit_code)
+ return tbl->reason;
+ tbl++;
+ }
+
+ pr_debug("Unknown hcall code: %lld\n",
+ (unsigned long long)exit_code);
+ return "UNKNOWN";
+}
+
+static bool hcall_event_end(struct perf_evsel *evsel,
+ struct perf_sample *sample __maybe_unused,
+ struct event_key *key __maybe_unused)
+{
+ return (!strcmp(evsel->name, kvm_events_tp[3]));
+}
+
+static bool hcall_event_begin(struct perf_evsel *evsel,
+ struct perf_sample *sample, struct event_key *key)
+{
+ if (!strcmp(evsel->name, kvm_events_tp[2])) {
+ hcall_event_get_key(evsel, sample, key);
+ return true;
+ }
+
+ return false;
+}
+static void hcall_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
+ struct event_key *key,
+ char *decode)
+{
+ const char *hcall_reason = get_hcall_exit_reason(key->key);
+
+ scnprintf(decode, decode_str_len, "%s", hcall_reason);
+}
+
+static struct kvm_events_ops hcall_events = {
+ .is_begin_event = hcall_event_begin,
+ .is_end_event = hcall_event_end,
+ .decode_key = hcall_event_decode_key,
+ .name = "HCALL-EVENT",
+};
+
static struct kvm_events_ops exit_events = {
.is_begin_event = exit_event_begin,
.is_end_event = exit_event_end,
@@ -31,6 +93,7 @@ static struct kvm_events_ops exit_events = {

struct kvm_reg_events_ops kvm_reg_events_ops[] = {
{ .name = "vmexit", .ops = &exit_events },
+ { .name = "hcall", .ops = &hcall_events },
{ NULL, NULL },
};

--
1.9.3