tools/perf/util/intel-pt-decoder/intel-pt-log.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * intel_pt_log.c: Intel Processor Trace support
   4  * Copyright (c) 2013-2014, Intel Corporation.
   5  */
   6
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <stdint.h>
  10 #include <inttypes.h>
  11 #include <stdarg.h>
  12 #include <stdbool.h>
  13 #include <string.h>
  14
  15 #include <linux/zalloc.h>
  16 #include <linux/kernel.h>
  17
  18 #include "intel-pt-log.h"
  19 #include "intel-pt-insn-decoder.h"
  20
  21 #include "intel-pt-pkt-decoder.h"
  22
  23 #define MAX_LOG_NAME 256
  24
  25 #define DFLT_BUF_SZ     (16 * 1024)
  26
  27 struct log_buf {
  28         char                    *buf;
  29         size_t                  buf_sz;
  30         size_t                  head;
  31         bool                    wrapped;
  32         FILE                    *backend;
  33 };
  34
  35 static FILE *f;
  36 static char log_name[MAX_LOG_NAME];
  37 bool intel_pt_enable_logging;
  38 static bool intel_pt_dump_log_on_error;
  39 static unsigned int intel_pt_log_on_error_size;
  40 static struct log_buf log_buf;
  41
  42 void *intel_pt_log_fp(void)
  43 {
  44         return f;
  45 }
  46
  47 void intel_pt_log_enable(bool dump_log_on_error, unsigned int log_on_error_size)
  48 {
  49         intel_pt_enable_logging = true;
  50         intel_pt_dump_log_on_error = dump_log_on_error;
  51         intel_pt_log_on_error_size = log_on_error_size;
  52 }
  53
  54 void intel_pt_log_disable(void)
  55 {
  56         if (f)
  57                 fflush(f);
  58         intel_pt_enable_logging = false;
  59 }
  60
  61 void intel_pt_log_set_name(const char *name)
  62 {
  63         strncpy(log_name, name, MAX_LOG_NAME - 5);
  64         strcat(log_name, ".log");
  65 }
  66
  67 static void intel_pt_print_data(const unsigned char *buf, int len, uint64_t pos,
  68                                 int indent)
  69 {
  70         int i;
  71
  72         for (i = 0; i < indent; i++)
  73                 fprintf(f, " ");
  74
  75         fprintf(f, "  %08" PRIx64 ": ", pos);
  76         for (i = 0; i < len; i++)
  77                 fprintf(f, " %02x", buf[i]);
  78         for (; i < 16; i++)
  79                 fprintf(f, "   ");
  80         fprintf(f, " ");
  81 }
  82
  83 static void intel_pt_print_no_data(uint64_t pos, int indent)
  84 {
  85         int i;
  86
  87         for (i = 0; i < indent; i++)
  88                 fprintf(f, " ");
  89
  90         fprintf(f, "  %08" PRIx64 ": ", pos);
  91         for (i = 0; i < 16; i++)
  92                 fprintf(f, "   ");
  93         fprintf(f, " ");
  94 }
  95
  96 static ssize_t log_buf__write(void *cookie, const char *buf, size_t size)
  97 {
  98         struct log_buf *b = cookie;
  99         size_t sz = size;
 100
 101         if (!b->buf)
 102                 return size;
 103
 104         while (sz) {
 105                 size_t space = b->buf_sz - b->head;
 106                 size_t n = min(space, sz);
 107
 108                 memcpy(b->buf + b->head, buf, n);
 109                 sz -= n;
 110                 buf += n;
 111                 b->head += n;
 112                 if (sz && b->head >= b->buf_sz) {
 113                         b->head = 0;
 114                         b->wrapped = true;
 115                 }
 116         }
 117         return size;
 118 }
 119
 120 static int log_buf__close(void *cookie)
 121 {
 122         struct log_buf *b = cookie;
 123
 124         zfree(&b->buf);
 125         return 0;
 126 }
 127
 128 static FILE *log_buf__open(struct log_buf *b, FILE *backend, unsigned int sz)
 129 {
 130         cookie_io_functions_t fns = {
 131                 .write = log_buf__write,
 132                 .close = log_buf__close,
 133         };
 134         FILE *file;
 135
 136         memset(b, 0, sizeof(*b));
 137         b->buf_sz = sz;
 138         b->buf = malloc(b->buf_sz);
 139         b->backend = backend;
 140         file = fopencookie(b, "a", fns);
 141         if (!file)
 142                 zfree(&b->buf);
 143         return file;
 144 }
 145
 146 static bool remove_first_line(const char **p, size_t *n)
 147 {
 148         for (; *n && **p != '\n'; ++*p, --*n)
 149                 ;
 150         if (*n) {
 151                 *p += 1;
 152                 *n -= 1;
 153                 return true;
 154         }
 155         return false;
 156 }
 157
 158 static void write_lines(const char *p, size_t n, FILE *fp, bool *remove_first)
 159 {
 160         if (*remove_first)
 161                 *remove_first = !remove_first_line(&p, &n);
 162         fwrite(p, n, 1, fp);
 163 }
 164
 165 static void log_buf__dump(struct log_buf *b)
 166 {
 167         bool remove_first = false;
 168
 169         if (!b->buf)
 170                 return;
 171
 172         fflush(f); /* Could update b->head and b->wrapped */
 173         fprintf(b->backend, "Dumping debug log buffer\n");
 174         if (b->wrapped) {
 175                 remove_first = true;
 176                 write_lines(b->buf + b->head, b->buf_sz - b->head, b->backend, &remove_first);
 177         }
 178         write_lines(b->buf, b->head, b->backend, &remove_first);
 179         fprintf(b->backend, "End of debug log buffer dump\n");
 180
 181         b->head = 0;
 182         b->wrapped = false;
 183 }
 184
 185 void intel_pt_log_dump_buf(void)
 186 {
 187         log_buf__dump(&log_buf);
 188 }
 189
 190 static int intel_pt_log_open(void)
 191 {
 192         if (!intel_pt_enable_logging)
 193                 return -1;
 194
 195         if (f)
 196                 return 0;
 197
 198         if (log_name[0])
 199                 f = fopen(log_name, "w+");
 200         else
 201                 f = stdout;
 202         if (f && intel_pt_dump_log_on_error)
 203                 f = log_buf__open(&log_buf, f, intel_pt_log_on_error_size);
 204         if (!f) {
 205                 intel_pt_enable_logging = false;
 206                 return -1;
 207         }
 208
 209         return 0;
 210 }
 211
 212 void __intel_pt_log_packet(const struct intel_pt_pkt *packet, int pkt_len,
 213                            uint64_t pos, const unsigned char *buf)
 214 {
 215         char desc[INTEL_PT_PKT_DESC_MAX];
 216
 217         if (intel_pt_log_open())
 218                 return;
 219
 220         intel_pt_print_data(buf, pkt_len, pos, 0);
 221         intel_pt_pkt_desc(packet, desc, INTEL_PT_PKT_DESC_MAX);
 222         fprintf(f, "%s\n", desc);
 223 }
 224
 225 void __intel_pt_log_insn(struct intel_pt_insn *intel_pt_insn, uint64_t ip)
 226 {
 227         char desc[INTEL_PT_INSN_DESC_MAX];
 228         size_t len = intel_pt_insn->length;
 229
 230         if (intel_pt_log_open())
 231                 return;
 232
 233         if (len > INTEL_PT_INSN_BUF_SZ)
 234                 len = INTEL_PT_INSN_BUF_SZ;
 235         intel_pt_print_data(intel_pt_insn->buf, len, ip, 8);
 236         if (intel_pt_insn_desc(intel_pt_insn, desc, INTEL_PT_INSN_DESC_MAX) > 0)
 237                 fprintf(f, "%s\n", desc);
 238         else
 239                 fprintf(f, "Bad instruction!\n");
 240 }
 241
 242 void __intel_pt_log_insn_no_data(struct intel_pt_insn *intel_pt_insn,
 243                                  uint64_t ip)
 244 {
 245         char desc[INTEL_PT_INSN_DESC_MAX];
 246
 247         if (intel_pt_log_open())
 248                 return;
 249
 250         intel_pt_print_no_data(ip, 8);
 251         if (intel_pt_insn_desc(intel_pt_insn, desc, INTEL_PT_INSN_DESC_MAX) > 0)
 252                 fprintf(f, "%s\n", desc);
 253         else
 254                 fprintf(f, "Bad instruction!\n");
 255 }
 256
 257 void __intel_pt_log(const char *fmt, ...)
 258 {
 259         va_list args;
 260
 261         if (intel_pt_log_open())
 262                 return;
 263
 264         va_start(args, fmt);
 265         vfprintf(f, fmt, args);
 266         va_end(args);
 267 }