xref: /linux/tools/perf/arch/powerpc/util/kvm-stat.c (revision 79790b6818e96c58fe2bffee1b418c16e64e7b80)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include "util/kvm-stat.h"
4 #include "util/parse-events.h"
5 #include "util/debug.h"
6 #include "util/evsel.h"
7 #include "util/evlist.h"
8 #include "util/pmus.h"
9 
10 #include "book3s_hv_exits.h"
11 #include "book3s_hcalls.h"
12 #include <subcmd/parse-options.h>
13 
14 #define NR_TPS 4
15 
16 const char *vcpu_id_str = "vcpu_id";
17 const char *kvm_entry_trace = "kvm_hv:kvm_guest_enter";
18 const char *kvm_exit_trace = "kvm_hv:kvm_guest_exit";
19 
20 define_exit_reasons_table(hv_exit_reasons, kvm_trace_symbol_exit);
21 define_exit_reasons_table(hcall_reasons, kvm_trace_symbol_hcall);
22 
23 /* Tracepoints specific to ppc_book3s_hv */
24 const char *ppc_book3s_hv_kvm_tp[] = {
25 	"kvm_hv:kvm_guest_enter",
26 	"kvm_hv:kvm_guest_exit",
27 	"kvm_hv:kvm_hcall_enter",
28 	"kvm_hv:kvm_hcall_exit",
29 	NULL,
30 };
31 
32 /* 1 extra placeholder for NULL */
33 const char *kvm_events_tp[NR_TPS + 1];
34 const char *kvm_exit_reason;
35 
hcall_event_get_key(struct evsel * evsel,struct perf_sample * sample,struct event_key * key)36 static void hcall_event_get_key(struct evsel *evsel,
37 				struct perf_sample *sample,
38 				struct event_key *key)
39 {
40 	key->info = 0;
41 	key->key = evsel__intval(evsel, sample, "req");
42 }
43 
get_hcall_exit_reason(u64 exit_code)44 static const char *get_hcall_exit_reason(u64 exit_code)
45 {
46 	struct exit_reasons_table *tbl = hcall_reasons;
47 
48 	while (tbl->reason != NULL) {
49 		if (tbl->exit_code == exit_code)
50 			return tbl->reason;
51 		tbl++;
52 	}
53 
54 	pr_debug("Unknown hcall code: %lld\n",
55 	       (unsigned long long)exit_code);
56 	return "UNKNOWN";
57 }
58 
hcall_event_end(struct evsel * evsel,struct perf_sample * sample __maybe_unused,struct event_key * key __maybe_unused)59 static bool hcall_event_end(struct evsel *evsel,
60 			    struct perf_sample *sample __maybe_unused,
61 			    struct event_key *key __maybe_unused)
62 {
63 	return (evsel__name_is(evsel, kvm_events_tp[3]));
64 }
65 
hcall_event_begin(struct evsel * evsel,struct perf_sample * sample,struct event_key * key)66 static bool hcall_event_begin(struct evsel *evsel,
67 			      struct perf_sample *sample, struct event_key *key)
68 {
69 	if (evsel__name_is(evsel, kvm_events_tp[2])) {
70 		hcall_event_get_key(evsel, sample, key);
71 		return true;
72 	}
73 
74 	return false;
75 }
hcall_event_decode_key(struct perf_kvm_stat * kvm __maybe_unused,struct event_key * key,char * decode)76 static void hcall_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
77 				   struct event_key *key,
78 				   char *decode)
79 {
80 	const char *hcall_reason = get_hcall_exit_reason(key->key);
81 
82 	scnprintf(decode, KVM_EVENT_NAME_LEN, "%s", hcall_reason);
83 }
84 
85 static struct kvm_events_ops hcall_events = {
86 	.is_begin_event = hcall_event_begin,
87 	.is_end_event = hcall_event_end,
88 	.decode_key = hcall_event_decode_key,
89 	.name = "HCALL-EVENT",
90 };
91 
92 static struct kvm_events_ops exit_events = {
93 	.is_begin_event = exit_event_begin,
94 	.is_end_event = exit_event_end,
95 	.decode_key = exit_event_decode_key,
96 	.name = "VM-EXIT"
97 };
98 
99 struct kvm_reg_events_ops kvm_reg_events_ops[] = {
100 	{ .name = "vmexit", .ops = &exit_events },
101 	{ .name = "hcall", .ops = &hcall_events },
102 	{ NULL, NULL },
103 };
104 
105 const char * const kvm_skip_events[] = {
106 	NULL,
107 };
108 
109 
is_tracepoint_available(const char * str,struct evlist * evlist)110 static int is_tracepoint_available(const char *str, struct evlist *evlist)
111 {
112 	struct parse_events_error err;
113 	int ret;
114 
115 	parse_events_error__init(&err);
116 	ret = parse_events(evlist, str, &err);
117 	if (ret)
118 		parse_events_error__print(&err, "tracepoint");
119 	parse_events_error__exit(&err);
120 	return ret;
121 }
122 
ppc__setup_book3s_hv(struct perf_kvm_stat * kvm,struct evlist * evlist)123 static int ppc__setup_book3s_hv(struct perf_kvm_stat *kvm,
124 				struct evlist *evlist)
125 {
126 	const char **events_ptr;
127 	int i, nr_tp = 0, err = -1;
128 
129 	/* Check for book3s_hv tracepoints */
130 	for (events_ptr = ppc_book3s_hv_kvm_tp; *events_ptr; events_ptr++) {
131 		err = is_tracepoint_available(*events_ptr, evlist);
132 		if (err)
133 			return -1;
134 		nr_tp++;
135 	}
136 
137 	for (i = 0; i < nr_tp; i++)
138 		kvm_events_tp[i] = ppc_book3s_hv_kvm_tp[i];
139 
140 	kvm_events_tp[i] = NULL;
141 	kvm_exit_reason = "trap";
142 	kvm->exit_reasons = hv_exit_reasons;
143 	kvm->exit_reasons_isa = "HV";
144 
145 	return 0;
146 }
147 
148 /* Wrapper to setup kvm tracepoints */
ppc__setup_kvm_tp(struct perf_kvm_stat * kvm)149 static int ppc__setup_kvm_tp(struct perf_kvm_stat *kvm)
150 {
151 	struct evlist *evlist = evlist__new();
152 
153 	if (evlist == NULL)
154 		return -ENOMEM;
155 
156 	/* Right now, only supported on book3s_hv */
157 	return ppc__setup_book3s_hv(kvm, evlist);
158 }
159 
setup_kvm_events_tp(struct perf_kvm_stat * kvm)160 int setup_kvm_events_tp(struct perf_kvm_stat *kvm)
161 {
162 	return ppc__setup_kvm_tp(kvm);
163 }
164 
cpu_isa_init(struct perf_kvm_stat * kvm,const char * cpuid __maybe_unused)165 int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid __maybe_unused)
166 {
167 	int ret;
168 
169 	ret = ppc__setup_kvm_tp(kvm);
170 	if (ret) {
171 		kvm->exit_reasons = NULL;
172 		kvm->exit_reasons_isa = NULL;
173 	}
174 
175 	return ret;
176 }
177 
178 /*
179  * In case of powerpc architecture, pmu registers are programmable
180  * by guest kernel. So monitoring guest via host may not provide
181  * valid samples with default 'cycles' event. It is better to use
182  * 'trace_imc/trace_cycles' event for guest profiling, since it
183  * can track the guest instruction pointer in the trace-record.
184  *
185  * Function to parse the arguments and return appropriate values.
186  */
kvm_add_default_arch_event(int * argc,const char ** argv)187 int kvm_add_default_arch_event(int *argc, const char **argv)
188 {
189 	const char **tmp;
190 	bool event = false;
191 	int i, j = *argc;
192 
193 	const struct option event_options[] = {
194 		OPT_BOOLEAN('e', "event", &event, NULL),
195 		OPT_END()
196 	};
197 
198 	tmp = calloc(j + 1, sizeof(char *));
199 	if (!tmp)
200 		return -EINVAL;
201 
202 	for (i = 0; i < j; i++)
203 		tmp[i] = argv[i];
204 
205 	parse_options(j, tmp, event_options, NULL, PARSE_OPT_KEEP_UNKNOWN);
206 	if (!event) {
207 		if (perf_pmus__have_event("trace_imc", "trace_cycles")) {
208 			argv[j++] = strdup("-e");
209 			argv[j++] = strdup("trace_imc/trace_cycles/");
210 			*argc += 2;
211 		} else {
212 			free(tmp);
213 			return -EINVAL;
214 		}
215 	}
216 
217 	free(tmp);
218 	return 0;
219 }
220