1// SPDX-License-Identifier: GPL-2.0
  2
  3#include <stdio.h>
  4#include <string.h>
  5#include <stdbool.h>
  6#include <stdint.h>
  7#include <sys/mman.h>
  8#include <unistd.h>
  9#include <sdt.h>
 10
 11#ifndef MADV_POPULATE_READ
 12#define MADV_POPULATE_READ 22
 13#endif
 14
 15#ifndef MADV_PAGEOUT
 16#define MADV_PAGEOUT 21
 17#endif
 18
 19int __attribute__((weak)) uprobe(void)
 20{
 21	return 0;
 22}
 23
 24#define __PASTE(a, b) a##b
 25#define PASTE(a, b) __PASTE(a, b)
 26
 27#define NAME(name, idx) PASTE(name, idx)
 28
 29#define DEF(name, idx) int __attribute__((weak)) NAME(name, idx)(void) { return 0; }
 30#define CALL(name, idx) NAME(name, idx)();
 31
 32#define F(body, name, idx) body(name, idx)
 33
 34#define F10(body, name, idx) \
 35	F(body, PASTE(name, idx), 0) F(body, PASTE(name, idx), 1) F(body, PASTE(name, idx), 2) \
 36	F(body, PASTE(name, idx), 3) F(body, PASTE(name, idx), 4) F(body, PASTE(name, idx), 5) \
 37	F(body, PASTE(name, idx), 6) F(body, PASTE(name, idx), 7) F(body, PASTE(name, idx), 8) \
 38	F(body, PASTE(name, idx), 9)
 39
 40#define F100(body, name, idx) \
 41	F10(body, PASTE(name, idx), 0) F10(body, PASTE(name, idx), 1) F10(body, PASTE(name, idx), 2) \
 42	F10(body, PASTE(name, idx), 3) F10(body, PASTE(name, idx), 4) F10(body, PASTE(name, idx), 5) \
 43	F10(body, PASTE(name, idx), 6) F10(body, PASTE(name, idx), 7) F10(body, PASTE(name, idx), 8) \
 44	F10(body, PASTE(name, idx), 9)
 45
 46#define F1000(body, name, idx) \
 47	F100(body, PASTE(name, idx), 0) F100(body, PASTE(name, idx), 1) F100(body, PASTE(name, idx), 2) \
 48	F100(body, PASTE(name, idx), 3) F100(body, PASTE(name, idx), 4) F100(body, PASTE(name, idx), 5) \
 49	F100(body, PASTE(name, idx), 6) F100(body, PASTE(name, idx), 7) F100(body, PASTE(name, idx), 8) \
 50	F100(body, PASTE(name, idx), 9)
 51
 52#define F10000(body, name, idx) \
 53	F1000(body, PASTE(name, idx), 0) F1000(body, PASTE(name, idx), 1) F1000(body, PASTE(name, idx), 2) \
 54	F1000(body, PASTE(name, idx), 3) F1000(body, PASTE(name, idx), 4) F1000(body, PASTE(name, idx), 5) \
 55	F1000(body, PASTE(name, idx), 6) F1000(body, PASTE(name, idx), 7) F1000(body, PASTE(name, idx), 8) \
 56	F1000(body, PASTE(name, idx), 9)
 57
 58F10000(DEF, uprobe_multi_func_, 0)
 59F10000(DEF, uprobe_multi_func_, 1)
 60F10000(DEF, uprobe_multi_func_, 2)
 61F10000(DEF, uprobe_multi_func_, 3)
 62F10000(DEF, uprobe_multi_func_, 4)
 63
 64static int bench(void)
 65{
 66	F10000(CALL, uprobe_multi_func_, 0)
 67	F10000(CALL, uprobe_multi_func_, 1)
 68	F10000(CALL, uprobe_multi_func_, 2)
 69	F10000(CALL, uprobe_multi_func_, 3)
 70	F10000(CALL, uprobe_multi_func_, 4)
 71	return 0;
 72}
 73
 74#define PROBE STAP_PROBE(test, usdt);
 75
 76#define PROBE10    PROBE PROBE PROBE PROBE PROBE \
 77		   PROBE PROBE PROBE PROBE PROBE
 78#define PROBE100   PROBE10 PROBE10 PROBE10 PROBE10 PROBE10 \
 79		   PROBE10 PROBE10 PROBE10 PROBE10 PROBE10
 80#define PROBE1000  PROBE100 PROBE100 PROBE100 PROBE100 PROBE100 \
 81		   PROBE100 PROBE100 PROBE100 PROBE100 PROBE100
 82#define PROBE10000 PROBE1000 PROBE1000 PROBE1000 PROBE1000 PROBE1000 \
 83		   PROBE1000 PROBE1000 PROBE1000 PROBE1000 PROBE1000
 84
 85static int usdt(void)
 86{
 87	PROBE10000
 88	PROBE10000
 89	PROBE10000
 90	PROBE10000
 91	PROBE10000
 92	return 0;
 93}
 94
 95extern char build_id_start[];
 96extern char build_id_end[];
 97
 98int __attribute__((weak)) trigger_uprobe(bool build_id_resident)
 99{
100	int page_sz = sysconf(_SC_PAGESIZE);
101	void *addr;
102
103	/* page-align build ID start */
104	addr = (void *)((uintptr_t)&build_id_start & ~(page_sz - 1));
105
106	/* to guarantee MADV_PAGEOUT work reliably, we need to ensure that
107	 * memory range is mapped into current process, so we unconditionally
108	 * do MADV_POPULATE_READ, and then MADV_PAGEOUT, if necessary
109	 */
110	madvise(addr, page_sz, MADV_POPULATE_READ);
111	if (!build_id_resident)
112		madvise(addr, page_sz, MADV_PAGEOUT);
113
114	(void)uprobe();
115
116	return 0;
117}
118
119int main(int argc, char **argv)
120{
121	if (argc != 2)
122		goto error;
123
124	if (!strcmp("bench", argv[1]))
125		return bench();
126	if (!strcmp("usdt", argv[1]))
127		return usdt();
128	if (!strcmp("uprobe-paged-out", argv[1]))
129		return trigger_uprobe(false /* page-out build ID */);
130	if (!strcmp("uprobe-paged-in", argv[1]))
131		return trigger_uprobe(true /* page-in build ID */);
132
133error:
134	fprintf(stderr, "usage: %s <bench|usdt>\n", argv[0]);
135	return -1;
136}