xref: /OK3568_Linux_fs/kernel/tools/perf/util/srccode.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Manage printing of source lines
4*4882a593Smuzhiyun  * Copyright (c) 2017, Intel Corporation.
5*4882a593Smuzhiyun  * Author: Andi Kleen
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun #include <linux/list.h>
8*4882a593Smuzhiyun #include <linux/zalloc.h>
9*4882a593Smuzhiyun #include <stdlib.h>
10*4882a593Smuzhiyun #include <sys/mman.h>
11*4882a593Smuzhiyun #include <sys/stat.h>
12*4882a593Smuzhiyun #include <fcntl.h>
13*4882a593Smuzhiyun #include <unistd.h>
14*4882a593Smuzhiyun #include <assert.h>
15*4882a593Smuzhiyun #include <string.h>
16*4882a593Smuzhiyun #include "srccode.h"
17*4882a593Smuzhiyun #include "debug.h"
18*4882a593Smuzhiyun #include <internal/lib.h> // page_size
19*4882a593Smuzhiyun #include "fncache.h"
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun #define MAXSRCCACHE (32*1024*1024)
22*4882a593Smuzhiyun #define MAXSRCFILES     64
23*4882a593Smuzhiyun #define SRC_HTAB_SZ	64
24*4882a593Smuzhiyun 
25*4882a593Smuzhiyun struct srcfile {
26*4882a593Smuzhiyun 	struct hlist_node hash_nd;
27*4882a593Smuzhiyun 	struct list_head nd;
28*4882a593Smuzhiyun 	char *fn;
29*4882a593Smuzhiyun 	char **lines;
30*4882a593Smuzhiyun 	char *map;
31*4882a593Smuzhiyun 	unsigned numlines;
32*4882a593Smuzhiyun 	size_t maplen;
33*4882a593Smuzhiyun };
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun static struct hlist_head srcfile_htab[SRC_HTAB_SZ];
36*4882a593Smuzhiyun static LIST_HEAD(srcfile_list);
37*4882a593Smuzhiyun static long map_total_sz;
38*4882a593Smuzhiyun static int num_srcfiles;
39*4882a593Smuzhiyun 
countlines(char * map,int maplen)40*4882a593Smuzhiyun static int countlines(char *map, int maplen)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun 	int numl;
43*4882a593Smuzhiyun 	char *end = map + maplen;
44*4882a593Smuzhiyun 	char *p = map;
45*4882a593Smuzhiyun 
46*4882a593Smuzhiyun 	if (maplen == 0)
47*4882a593Smuzhiyun 		return 0;
48*4882a593Smuzhiyun 	numl = 0;
49*4882a593Smuzhiyun 	while (p < end && (p = memchr(p, '\n', end - p)) != NULL) {
50*4882a593Smuzhiyun 		numl++;
51*4882a593Smuzhiyun 		p++;
52*4882a593Smuzhiyun 	}
53*4882a593Smuzhiyun 	if (p < end)
54*4882a593Smuzhiyun 		numl++;
55*4882a593Smuzhiyun 	return numl;
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun 
fill_lines(char ** lines,int maxline,char * map,int maplen)58*4882a593Smuzhiyun static void fill_lines(char **lines, int maxline, char *map, int maplen)
59*4882a593Smuzhiyun {
60*4882a593Smuzhiyun 	int l;
61*4882a593Smuzhiyun 	char *end = map + maplen;
62*4882a593Smuzhiyun 	char *p = map;
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun 	if (maplen == 0 || maxline == 0)
65*4882a593Smuzhiyun 		return;
66*4882a593Smuzhiyun 	l = 0;
67*4882a593Smuzhiyun 	lines[l++] = map;
68*4882a593Smuzhiyun 	while (p < end && (p = memchr(p, '\n', end - p)) != NULL) {
69*4882a593Smuzhiyun 		if (l >= maxline)
70*4882a593Smuzhiyun 			return;
71*4882a593Smuzhiyun 		lines[l++] = ++p;
72*4882a593Smuzhiyun 	}
73*4882a593Smuzhiyun 	if (p < end)
74*4882a593Smuzhiyun 		lines[l] = p;
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun 
free_srcfile(struct srcfile * sf)77*4882a593Smuzhiyun static void free_srcfile(struct srcfile *sf)
78*4882a593Smuzhiyun {
79*4882a593Smuzhiyun 	list_del_init(&sf->nd);
80*4882a593Smuzhiyun 	hlist_del(&sf->hash_nd);
81*4882a593Smuzhiyun 	map_total_sz -= sf->maplen;
82*4882a593Smuzhiyun 	munmap(sf->map, sf->maplen);
83*4882a593Smuzhiyun 	zfree(&sf->lines);
84*4882a593Smuzhiyun 	zfree(&sf->fn);
85*4882a593Smuzhiyun 	free(sf);
86*4882a593Smuzhiyun 	num_srcfiles--;
87*4882a593Smuzhiyun }
88*4882a593Smuzhiyun 
find_srcfile(char * fn)89*4882a593Smuzhiyun static struct srcfile *find_srcfile(char *fn)
90*4882a593Smuzhiyun {
91*4882a593Smuzhiyun 	struct stat st;
92*4882a593Smuzhiyun 	struct srcfile *h;
93*4882a593Smuzhiyun 	int fd;
94*4882a593Smuzhiyun 	unsigned long sz;
95*4882a593Smuzhiyun 	unsigned hval = shash((unsigned char *)fn) % SRC_HTAB_SZ;
96*4882a593Smuzhiyun 
97*4882a593Smuzhiyun 	hlist_for_each_entry (h, &srcfile_htab[hval], hash_nd) {
98*4882a593Smuzhiyun 		if (!strcmp(fn, h->fn)) {
99*4882a593Smuzhiyun 			/* Move to front */
100*4882a593Smuzhiyun 			list_del(&h->nd);
101*4882a593Smuzhiyun 			list_add(&h->nd, &srcfile_list);
102*4882a593Smuzhiyun 			return h;
103*4882a593Smuzhiyun 		}
104*4882a593Smuzhiyun 	}
105*4882a593Smuzhiyun 
106*4882a593Smuzhiyun 	/* Only prune if there is more than one entry */
107*4882a593Smuzhiyun 	while ((num_srcfiles > MAXSRCFILES || map_total_sz > MAXSRCCACHE) &&
108*4882a593Smuzhiyun 	       srcfile_list.next != &srcfile_list) {
109*4882a593Smuzhiyun 		assert(!list_empty(&srcfile_list));
110*4882a593Smuzhiyun 		h = list_entry(srcfile_list.prev, struct srcfile, nd);
111*4882a593Smuzhiyun 		free_srcfile(h);
112*4882a593Smuzhiyun 	}
113*4882a593Smuzhiyun 
114*4882a593Smuzhiyun 	fd = open(fn, O_RDONLY);
115*4882a593Smuzhiyun 	if (fd < 0 || fstat(fd, &st) < 0) {
116*4882a593Smuzhiyun 		pr_debug("cannot open source file %s\n", fn);
117*4882a593Smuzhiyun 		return NULL;
118*4882a593Smuzhiyun 	}
119*4882a593Smuzhiyun 
120*4882a593Smuzhiyun 	h = malloc(sizeof(struct srcfile));
121*4882a593Smuzhiyun 	if (!h)
122*4882a593Smuzhiyun 		return NULL;
123*4882a593Smuzhiyun 
124*4882a593Smuzhiyun 	h->fn = strdup(fn);
125*4882a593Smuzhiyun 	if (!h->fn)
126*4882a593Smuzhiyun 		goto out_h;
127*4882a593Smuzhiyun 
128*4882a593Smuzhiyun 	h->maplen = st.st_size;
129*4882a593Smuzhiyun 	sz = (h->maplen + page_size - 1) & ~(page_size - 1);
130*4882a593Smuzhiyun 	h->map = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0);
131*4882a593Smuzhiyun 	close(fd);
132*4882a593Smuzhiyun 	if (h->map == (char *)-1) {
133*4882a593Smuzhiyun 		pr_debug("cannot mmap source file %s\n", fn);
134*4882a593Smuzhiyun 		goto out_fn;
135*4882a593Smuzhiyun 	}
136*4882a593Smuzhiyun 	h->numlines = countlines(h->map, h->maplen);
137*4882a593Smuzhiyun 	h->lines = calloc(h->numlines, sizeof(char *));
138*4882a593Smuzhiyun 	if (!h->lines)
139*4882a593Smuzhiyun 		goto out_map;
140*4882a593Smuzhiyun 	fill_lines(h->lines, h->numlines, h->map, h->maplen);
141*4882a593Smuzhiyun 	list_add(&h->nd, &srcfile_list);
142*4882a593Smuzhiyun 	hlist_add_head(&h->hash_nd, &srcfile_htab[hval]);
143*4882a593Smuzhiyun 	map_total_sz += h->maplen;
144*4882a593Smuzhiyun 	num_srcfiles++;
145*4882a593Smuzhiyun 	return h;
146*4882a593Smuzhiyun 
147*4882a593Smuzhiyun out_map:
148*4882a593Smuzhiyun 	munmap(h->map, sz);
149*4882a593Smuzhiyun out_fn:
150*4882a593Smuzhiyun 	zfree(&h->fn);
151*4882a593Smuzhiyun out_h:
152*4882a593Smuzhiyun 	free(h);
153*4882a593Smuzhiyun 	return NULL;
154*4882a593Smuzhiyun }
155*4882a593Smuzhiyun 
156*4882a593Smuzhiyun /* Result is not 0 terminated */
find_sourceline(char * fn,unsigned line,int * lenp)157*4882a593Smuzhiyun char *find_sourceline(char *fn, unsigned line, int *lenp)
158*4882a593Smuzhiyun {
159*4882a593Smuzhiyun 	char *l, *p;
160*4882a593Smuzhiyun 	struct srcfile *sf = find_srcfile(fn);
161*4882a593Smuzhiyun 	if (!sf)
162*4882a593Smuzhiyun 		return NULL;
163*4882a593Smuzhiyun 	line--;
164*4882a593Smuzhiyun 	if (line >= sf->numlines)
165*4882a593Smuzhiyun 		return NULL;
166*4882a593Smuzhiyun 	l = sf->lines[line];
167*4882a593Smuzhiyun 	if (!l)
168*4882a593Smuzhiyun 		return NULL;
169*4882a593Smuzhiyun 	p = memchr(l, '\n', sf->map + sf->maplen - l);
170*4882a593Smuzhiyun 	*lenp = p - l;
171*4882a593Smuzhiyun 	return l;
172*4882a593Smuzhiyun }
173