xref: /openbmc/linux/tools/perf/arch/x86/util/event.c (revision 76426e23)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/types.h>
3 #include <linux/string.h>
4 #include <linux/zalloc.h>
5 
6 #include "../../../util/event.h"
7 #include "../../../util/synthetic-events.h"
8 #include "../../../util/machine.h"
9 #include "../../../util/tool.h"
10 #include "../../../util/map.h"
11 #include "../../../util/debug.h"
12 
13 #if defined(__x86_64__)
14 
15 int perf_event__synthesize_extra_kmaps(struct perf_tool *tool,
16 				       perf_event__handler_t process,
17 				       struct machine *machine)
18 {
19 	int rc = 0;
20 	struct map *pos;
21 	struct maps *kmaps = &machine->kmaps;
22 	union perf_event *event = zalloc(sizeof(event->mmap) +
23 					 machine->id_hdr_size);
24 
25 	if (!event) {
26 		pr_debug("Not enough memory synthesizing mmap event "
27 			 "for extra kernel maps\n");
28 		return -1;
29 	}
30 
31 	maps__for_each_entry(kmaps, pos) {
32 		struct kmap *kmap;
33 		size_t size;
34 
35 		if (!__map__is_extra_kernel_map(pos))
36 			continue;
37 
38 		kmap = map__kmap(pos);
39 
40 		size = sizeof(event->mmap) - sizeof(event->mmap.filename) +
41 		       PERF_ALIGN(strlen(kmap->name) + 1, sizeof(u64)) +
42 		       machine->id_hdr_size;
43 
44 		memset(event, 0, size);
45 
46 		event->mmap.header.type = PERF_RECORD_MMAP;
47 
48 		/*
49 		 * kernel uses 0 for user space maps, see kernel/perf_event.c
50 		 * __perf_event_mmap
51 		 */
52 		if (machine__is_host(machine))
53 			event->header.misc = PERF_RECORD_MISC_KERNEL;
54 		else
55 			event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
56 
57 		event->mmap.header.size = size;
58 
59 		event->mmap.start = pos->start;
60 		event->mmap.len   = pos->end - pos->start;
61 		event->mmap.pgoff = pos->pgoff;
62 		event->mmap.pid   = machine->pid;
63 
64 		strlcpy(event->mmap.filename, kmap->name, PATH_MAX);
65 
66 		if (perf_tool__process_synth_event(tool, event, machine,
67 						   process) != 0) {
68 			rc = -1;
69 			break;
70 		}
71 	}
72 
73 	free(event);
74 	return rc;
75 }
76 
77 #endif
78