Linux Perf
dwarf-unwind.c
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1 // SPDX-License-Identifier: GPL-2.0
2 #include <string.h>
3 #include "perf_regs.h"
4 #include "thread.h"
5 #include "map.h"
6 #include "event.h"
7 #include "debug.h"
8 #include "tests/tests.h"
9 
10 #define STACK_SIZE 8192
11 
12 static int sample_ustack(struct perf_sample *sample,
13  struct thread *thread, u64 *regs)
14 {
15  struct stack_dump *stack = &sample->user_stack;
16  struct map *map;
17  unsigned long sp;
18  u64 stack_size, *buf;
19 
20  buf = malloc(STACK_SIZE);
21  if (!buf) {
22  pr_debug("failed to allocate sample uregs data\n");
23  return -1;
24  }
25 
26  sp = (unsigned long) regs[PERF_REG_ARM_SP];
27 
28  map = map_groups__find(thread->mg, (u64)sp);
29  if (!map) {
30  pr_debug("failed to get stack map\n");
31  free(buf);
32  return -1;
33  }
34 
35  stack_size = map->end - sp;
36  stack_size = stack_size > STACK_SIZE ? STACK_SIZE : stack_size;
37 
38  memcpy(buf, (void *) sp, stack_size);
39  stack->data = (char *) buf;
40  stack->size = stack_size;
41  return 0;
42 }
43 
45  struct thread *thread)
46 {
47  struct regs_dump *regs = &sample->user_regs;
48  u64 *buf;
49 
50  buf = calloc(1, sizeof(u64) * PERF_REGS_MAX);
51  if (!buf) {
52  pr_debug("failed to allocate sample uregs data\n");
53  return -1;
54  }
55 
56  perf_regs_load(buf);
57  regs->abi = PERF_SAMPLE_REGS_ABI;
58  regs->regs = buf;
59  regs->mask = PERF_REGS_MASK;
60 
61  return sample_ustack(sample, thread, buf);
62 }
struct map_groups * mg
Definition: thread.h:23
#define STACK_SIZE
Definition: dwarf-unwind.c:10
u64 mask
Definition: event.h:104
static int sample_ustack(struct perf_sample *sample, struct thread *thread, u64 *regs)
Definition: dwarf-unwind.c:12
void perf_regs_load(u64 *regs)
void * malloc(YYSIZE_T)
Definition: thread.h:18
#define pr_debug(fmt,...)
Definition: json.h:27
char * data
Definition: event.h:115
#define PERF_SAMPLE_REGS_ABI
Definition: perf_regs.h:13
struct regs_dump user_regs
Definition: event.h:213
#define PERF_REGS_MASK
Definition: perf_regs.h:11
u64 abi
Definition: event.h:103
x86 movsq based memcpy() in arch/x86/lib/memcpy_64.S") MEMCPY_FN(memcpy_erms
static struct map * map_groups__find(struct map_groups *mg, u64 addr)
Definition: map.h:211
Definition: jevents.c:228
int test__arch_unwind_sample(struct perf_sample *sample, struct thread *thread)
Definition: dwarf-unwind.c:44
#define PERF_REGS_MAX
Definition: perf_regs.h:12
void free(void *)
u64 * regs
Definition: event.h:105
u64 size
Definition: event.h:114
u64 end
Definition: map.h:29
struct stack_dump user_stack
Definition: event.h:215