xref: /linux/tools/perf/arch/x86/util/kvm-stat.c (revision e7e86d7697c6ed1dbbde18d7185c35b6967945ed)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <string.h>
4 #include "../../../util/kvm-stat.h"
5 #include "../../../util/evsel.h"
6 #include "../../../util/env.h"
7 #include <asm/svm.h>
8 #include <asm/vmx.h>
9 #include <asm/kvm.h>
10 #include <subcmd/parse-options.h>
11 
12 define_exit_reasons_table(vmx_exit_reasons, VMX_EXIT_REASONS);
13 define_exit_reasons_table(svm_exit_reasons, SVM_EXIT_REASONS);
14 
15 static struct kvm_events_ops exit_events = {
16 	.is_begin_event = exit_event_begin,
17 	.is_end_event = exit_event_end,
18 	.decode_key = exit_event_decode_key,
19 	.name = "VM-EXIT"
20 };
21 
22 const char *vcpu_id_str = "vcpu_id";
23 const char *kvm_exit_reason = "exit_reason";
24 const char *kvm_entry_trace = "kvm:kvm_entry";
25 const char *kvm_exit_trace = "kvm:kvm_exit";
26 
27 /*
28  * For the mmio events, we treat:
29  * the time of MMIO write: kvm_mmio(KVM_TRACE_MMIO_WRITE...) -> kvm_entry
30  * the time of MMIO read: kvm_exit -> kvm_mmio(KVM_TRACE_MMIO_READ...).
31  */
32 static void mmio_event_get_key(struct evsel *evsel, struct perf_sample *sample,
33 			       struct event_key *key)
34 {
35 	key->key  = evsel__intval(evsel, sample, "gpa");
36 	key->info = evsel__intval(evsel, sample, "type");
37 }
38 
39 #define KVM_TRACE_MMIO_READ_UNSATISFIED 0
40 #define KVM_TRACE_MMIO_READ 1
41 #define KVM_TRACE_MMIO_WRITE 2
42 
43 static bool mmio_event_begin(struct evsel *evsel,
44 			     struct perf_sample *sample, struct event_key *key)
45 {
46 	/* MMIO read begin event in kernel. */
47 	if (kvm_exit_event(evsel))
48 		return true;
49 
50 	/* MMIO write begin event in kernel. */
51 	if (evsel__name_is(evsel, "kvm:kvm_mmio") &&
52 	    evsel__intval(evsel, sample, "type") == KVM_TRACE_MMIO_WRITE) {
53 		mmio_event_get_key(evsel, sample, key);
54 		return true;
55 	}
56 
57 	return false;
58 }
59 
60 static bool mmio_event_end(struct evsel *evsel, struct perf_sample *sample,
61 			   struct event_key *key)
62 {
63 	/* MMIO write end event in kernel. */
64 	if (kvm_entry_event(evsel))
65 		return true;
66 
67 	/* MMIO read end event in kernel.*/
68 	if (evsel__name_is(evsel, "kvm:kvm_mmio") &&
69 	    evsel__intval(evsel, sample, "type") == KVM_TRACE_MMIO_READ) {
70 		mmio_event_get_key(evsel, sample, key);
71 		return true;
72 	}
73 
74 	return false;
75 }
76 
77 static void mmio_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
78 				  struct event_key *key,
79 				  char *decode)
80 {
81 	scnprintf(decode, KVM_EVENT_NAME_LEN, "%#lx:%s",
82 		  (unsigned long)key->key,
83 		  key->info == KVM_TRACE_MMIO_WRITE ? "W" : "R");
84 }
85 
86 static struct kvm_events_ops mmio_events = {
87 	.is_begin_event = mmio_event_begin,
88 	.is_end_event = mmio_event_end,
89 	.decode_key = mmio_event_decode_key,
90 	.name = "MMIO Access"
91 };
92 
93  /* The time of emulation pio access is from kvm_pio to kvm_entry. */
94 static void ioport_event_get_key(struct evsel *evsel,
95 				 struct perf_sample *sample,
96 				 struct event_key *key)
97 {
98 	key->key  = evsel__intval(evsel, sample, "port");
99 	key->info = evsel__intval(evsel, sample, "rw");
100 }
101 
102 static bool ioport_event_begin(struct evsel *evsel,
103 			       struct perf_sample *sample,
104 			       struct event_key *key)
105 {
106 	if (evsel__name_is(evsel, "kvm:kvm_pio")) {
107 		ioport_event_get_key(evsel, sample, key);
108 		return true;
109 	}
110 
111 	return false;
112 }
113 
114 static bool ioport_event_end(struct evsel *evsel,
115 			     struct perf_sample *sample __maybe_unused,
116 			     struct event_key *key __maybe_unused)
117 {
118 	return kvm_entry_event(evsel);
119 }
120 
121 static void ioport_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
122 				    struct event_key *key,
123 				    char *decode)
124 {
125 	scnprintf(decode, KVM_EVENT_NAME_LEN, "%#llx:%s",
126 		  (unsigned long long)key->key,
127 		  key->info ? "POUT" : "PIN");
128 }
129 
130 static struct kvm_events_ops ioport_events = {
131 	.is_begin_event = ioport_event_begin,
132 	.is_end_event = ioport_event_end,
133 	.decode_key = ioport_event_decode_key,
134 	.name = "IO Port Access"
135 };
136 
137  /* The time of emulation msr is from kvm_msr to kvm_entry. */
138 static void msr_event_get_key(struct evsel *evsel,
139 				 struct perf_sample *sample,
140 				 struct event_key *key)
141 {
142 	key->key  = evsel__intval(evsel, sample, "ecx");
143 	key->info = evsel__intval(evsel, sample, "write");
144 }
145 
146 static bool msr_event_begin(struct evsel *evsel,
147 			       struct perf_sample *sample,
148 			       struct event_key *key)
149 {
150 	if (evsel__name_is(evsel, "kvm:kvm_msr")) {
151 		msr_event_get_key(evsel, sample, key);
152 		return true;
153 	}
154 
155 	return false;
156 }
157 
158 static bool msr_event_end(struct evsel *evsel,
159 			     struct perf_sample *sample __maybe_unused,
160 			     struct event_key *key __maybe_unused)
161 {
162 	return kvm_entry_event(evsel);
163 }
164 
165 static void msr_event_decode_key(struct perf_kvm_stat *kvm __maybe_unused,
166 				    struct event_key *key,
167 				    char *decode)
168 {
169 	scnprintf(decode, KVM_EVENT_NAME_LEN, "%#llx:%s",
170 		  (unsigned long long)key->key,
171 		  key->info ? "W" : "R");
172 }
173 
174 static struct kvm_events_ops msr_events = {
175 	.is_begin_event = msr_event_begin,
176 	.is_end_event = msr_event_end,
177 	.decode_key = msr_event_decode_key,
178 	.name = "MSR Access"
179 };
180 
181 const char *kvm_events_tp[] = {
182 	"kvm:kvm_entry",
183 	"kvm:kvm_exit",
184 	"kvm:kvm_mmio",
185 	"kvm:kvm_pio",
186 	"kvm:kvm_msr",
187 	NULL,
188 };
189 
190 struct kvm_reg_events_ops kvm_reg_events_ops[] = {
191 	{ .name = "vmexit", .ops = &exit_events },
192 	{ .name = "mmio", .ops = &mmio_events },
193 	{ .name = "ioport", .ops = &ioport_events },
194 	{ .name = "msr", .ops = &msr_events },
195 	{ NULL, NULL },
196 };
197 
198 const char * const kvm_skip_events[] = {
199 	"HLT",
200 	NULL,
201 };
202 
203 int cpu_isa_init(struct perf_kvm_stat *kvm, const char *cpuid)
204 {
205 	if (strstr(cpuid, "Intel")) {
206 		kvm->exit_reasons = vmx_exit_reasons;
207 		kvm->exit_reasons_isa = "VMX";
208 	} else if (strstr(cpuid, "AMD") || strstr(cpuid, "Hygon")) {
209 		kvm->exit_reasons = svm_exit_reasons;
210 		kvm->exit_reasons_isa = "SVM";
211 	} else
212 		return -ENOTSUP;
213 
214 	return 0;
215 }
216 
217 /*
218  * After KVM supports PEBS for guest on Intel platforms
219  * (https://lore.kernel.org/all/20220411101946.20262-1-likexu@tencent.com/),
220  * host loses the capability to sample guest with PEBS since all PEBS related
221  * MSRs are switched to guest value after vm-entry, like IA32_DS_AREA MSR is
222  * switched to guest GVA at vm-entry. This would lead to "perf kvm record"
223  * fails to sample guest on Intel platforms since "cycles:P" event is used to
224  * sample guest by default.
225  *
226  * So, to avoid this issue explicitly use "cycles" instead of "cycles:P" event
227  * by default to sample guest on Intel platforms.
228  */
229 int kvm_add_default_arch_event(int *argc, const char **argv)
230 {
231 	const char **tmp;
232 	bool event = false;
233 	int ret = 0, i, j = *argc;
234 
235 	const struct option event_options[] = {
236 		OPT_BOOLEAN('e', "event", &event, NULL),
237 		OPT_BOOLEAN(0, "pfm-events", &event, NULL),
238 		OPT_END()
239 	};
240 
241 	if (!x86__is_intel_cpu())
242 		return 0;
243 
244 	tmp = calloc(j + 1, sizeof(char *));
245 	if (!tmp)
246 		return -ENOMEM;
247 
248 	for (i = 0; i < j; i++)
249 		tmp[i] = argv[i];
250 
251 	parse_options(j, tmp, event_options, NULL, PARSE_OPT_KEEP_UNKNOWN);
252 	if (!event) {
253 		argv[j++] = STRDUP_FAIL_EXIT("-e");
254 		argv[j++] = STRDUP_FAIL_EXIT("cycles");
255 		*argc += 2;
256 	}
257 
258 	free(tmp);
259 	return 0;
260 
261 EXIT:
262 	free(tmp);
263 	return ret;
264 }
265