/* * Copyright (c) 2017 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include /** * @brief Initialize a maplog object * * Compute record and file size parameters * Create and map two log segments to seed the process * * @param[in/out] a init args structure * @return 0 => success, <0 => failure */ int clib_maplog_init (clib_maplog_init_args_t * a) { int i, fd, limit; int rv = 0; u8 zero = 0; u32 record_size_in_cache_lines; u64 file_size_in_records; clib_maplog_main_t *mm; clib_maplog_header_t _h, *h = &_h; ASSERT (a && a->mm); mm = a->mm; /* Already initialized? */ if (mm->flags & CLIB_MAPLOG_FLAG_INIT) return (-2); memset (mm, 0, sizeof (*mm)); record_size_in_cache_lines = (a->record_size_in_bytes + CLIB_CACHE_LINE_BYTES - 1) / CLIB_CACHE_LINE_BYTES; file_size_in_records = a->file_size_in_bytes / (record_size_in_cache_lines * CLIB_CACHE_LINE_BYTES); /* Round up file size in records to a power of 2, for speed... */ mm->log2_file_size_in_records = max_log2 (file_size_in_records); file_size_in_records = 1ULL << (mm->log2_file_size_in_records); a->file_size_in_bytes = file_size_in_records * record_size_in_cache_lines * CLIB_CACHE_LINE_BYTES; mm->file_basename = format (0, "%s", a->file_basename); if (vec_len (mm->file_basename) > ARRAY_LEN (h->file_basename)) { vec_free (mm->file_basename); return -11; } mm->file_size_in_records = file_size_in_records; mm->flags |= CLIB_MAPLOG_FLAG_INIT; mm->record_size_in_cachelines = record_size_in_cache_lines; limit = 2; if (a->maplog_is_circular) { mm->log2_file_size_in_records = 63; mm->flags |= CLIB_MAPLOG_FLAG_CIRCULAR; limit = 1; } /* * Map the one and only file for a circular log, * two files for a normal log. */ for (i = 0; i < limit; i++) { mm->filenames[i] = format (0, "%v_%d", mm->file_basename, mm->current_file_index++); vec_add1 (mm->filenames[i], 0); fd = open ((char *) mm->filenames[i], O_CREAT | O_RDWR | O_TRUNC, 0600); if (fd < 0) { rv = -3; goto fail; } if (lseek (fd, a->file_size_in_bytes - 1, SEEK_SET) == (off_t) - 1) { rv = -4; goto fail; } if (write (fd, &zero, 1) != 1) { rv = -5; goto fail; } mm->file_baseva[i] = mmap (0, a->file_size_in_bytes, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); if (mm->file_baseva[i] == (u8 *) MAP_FAILED) { clib_unix_warning ("mmap"); goto fail; } (void) close (fd); } memset (h, 0, sizeof (*h)); h->maplog_major_version = MAPLOG_MAJOR_VERSION; h->maplog_minor_version = MAPLOG_MINOR_VERSION; h->maplog_patch_version = MAPLOG_PATCH_VERSION; h->application_id = a->application_id; h->application_major_version = a->application_major_version; h->application_minor_version = a->application_minor_version; h->application_patch_version = a->application_patch_version; h->record_size_in_cachelines = record_size_in_cache_lines; h->cacheline_size = CLIB_CACHE_LINE_BYTES; h->file_size_in_records = file_size_in_records; h->number_of_records = ~0ULL; h->number_of_files = ~0ULL; h->maplog_flag_circular = a->maplog_is_circular; memcpy (h->file_basename, mm->file_basename, vec_len (mm->file_basename)); mm->header_filename = format (0, "%v_header", mm->file_basename); vec_add1 (mm->header_filename, 0); fd = open ((char *) mm->header_filename, O_CREAT | O_RDWR | O_TRUNC, 0600); if (fd < 0) { clib_unix_warning ("header create"); rv = -6; goto fail; } rv = write (fd, h, sizeof (*h)); if (rv != sizeof (*h)) { clib_unix_warning ("header write"); rv = -7; goto fail; } (void) close (fd); return 0; fail: if (fd >= 0) (void) close (fd); for (i = 0; i < limit; i++) { if (mm->file_baseva[i]) (void) munmap ((u8 *) mm->file_baseva[i], a->file_size_in_bytes); if (mm->filenames[i]) (void) unlink ((char *) mm->filenames[i]); vec_free (mm->filenames[i]); } if (mm->header_filename) { (void) unlink ((char *) mm->header_filename); vec_free (mm->header_filename); } return rv; } /* slow path: unmap a full log segment, and replace it */ u8 * _clib_maplog_get_entry_slowpath (clib_maplog_main_t * mm, u64 my_record_index) { int fd; u8 *rv; u8 zero = 0; u32 unmap_index = (mm->current_file_index) & 1; u64 file_size_in_bytes = mm->file_size_in_records * mm->record_size_in_cachelines * CLIB_CACHE_LINE_BYTES; /* This should never happen */ ASSERT ((mm->flags & CLIB_MAPLOG_FLAG_CIRCULAR) == 0); /* * Kill some time by calling format before we make the previous log * segment disappear. Obviously it won't do to call clib_maplog_get_entry(), * wait 100ms, and then fill in the log entry. */ vec_reset_length (mm->filenames[unmap_index]); mm->filenames[unmap_index] = format (mm->filenames[unmap_index], "%v_%d", mm->file_basename, mm->current_file_index++); /* Unmap the previous (full) segment */ (void) munmap ((u8 *) mm->file_baseva[unmap_index], file_size_in_bytes); /* Create a new segment */ fd = open ((char *) mm->filenames[unmap_index], O_CREAT | O_RDWR | O_TRUNC, 0600); /* This is not real error recovery... */ if (fd < 0) { clib_unix_warning ("creat"); abort (); } if (lseek (fd, file_size_in_bytes - 1, SEEK_SET) == (off_t) - 1) { clib_unix_warning ("lseek"); abort (); } if (write (fd, &zero, 1) != 1) { clib_unix_warning ("set-size write"); abort (); } mm->file_baseva[unmap_index] = mmap (0, file_size_in_bytes, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); if (mm->file_baseva[unmap_index] == (u8 *) MAP_FAILED) { clib_unix_warning ("mmap"); abort (); } (void) close (fd); rv = (u8 *) mm->file_baseva[(my_record_index >> mm->log2_file_size_in_records) & 1] + (my_record_index & (mm->file_size_in_records - 1)) * mm->record_size_in_cachelines * CLIB_CACHE_LINE_BYTES; return rv; } /** * @brief Update a mapped log header file * * Read the log header. Update the number of records, and number of files * @param[in/out] mm mapped log object */ void clib_maplog_update_header (clib_maplog_main_t * mm) { int fd, rv; clib_maplog_header_t _h, *h = &_h; if (!(mm->flags & CLIB_MAPLOG_FLAG_INIT)) return; /* Open the log header */ fd = open ((char *) mm->header_filename, O_RDWR, 0600); if (fd < 0) { clib_unix_warning ("reopen maplog header"); goto out; } /* Read the log */ rv = read (fd, h, sizeof (*h)); if (rv != sizeof (*h)) { clib_unix_warning ("read maplog header"); goto out; } /* Fix the header... */ h->number_of_records = mm->next_record_index; h->number_of_files = mm->current_file_index; h->maplog_flag_wrapped = (mm->flags & CLIB_MAPLOG_FLAG_WRAPPED) ? 1 : 0; /* Back to the beginning of the log header... */ if (lseek (fd, 0, SEEK_SET) < 0) { clib_unix_warning ("lseek to rewrite header"); goto out; } /* Rewrite the log header */ rv = write (fd, h, sizeof (*h)); if (rv != sizeof (*h)) clib_unix_warning ("rewrite header"); out: if (fd >= 0) (void) close (fd); } /** * @brief Close a mapped log, and update the log header file * * Unmap the current log segments. * Read the log header. Update the number of records, and number of files * * @param[in/out] mm mapped log object */ void clib_maplog_close (clib_maplog_main_t * mm) { int i, limit; u64 file_size_in_bytes; if (!(mm->flags & CLIB_MAPLOG_FLAG_INIT)) return; clib_maplog_update_header (mm); file_size_in_bytes = mm->file_size_in_records * mm->record_size_in_cachelines * CLIB_CACHE_LINE_BYTES; limit = (mm->flags & CLIB_MAPLOG_FLAG_CIRCULAR) ? 1 : 2; /* unmap current + next segments */ for (i = 0; i < limit; i++) { (void) munmap ((u8 *) mm->file_baseva[i], file_size_in_bytes); vec_free (mm->filenames[i]); } vec_free (mm->file_basename); vec_free (mm->header_filename); memset (mm, 0, sizeof (*mm)); } /** * @brief format a log header * * Usage: s = format (0, "%U", format_maplog_header, headerp, verbose); * @param [in] h clib_maplog_header_t pointer * @param [in] verbose self-explanatory */ u8 * format_maplog_header (u8 * s, va_list * args) { clib_maplog_header_t *h = va_arg (*args, clib_maplog_header_t *); int verbose = va_arg (*args, int); if (!verbose) goto brief; s = format (s, "basename %s ", h->file_basename); s = format (s, "log ver %d.%d.%d app id %u ver %d.%d.%d %s %s\n", h->maplog_major_version, h->maplog_minor_version, h->maplog_patch_version, h->application_id, h->application_major_version, h->application_minor_version, h->application_patch_version, h->maplog_flag_circular ? "circular" : "linear", h->maplog_flag_wrapped ? "wrapped" : "not wrapped"); s = format (s, " records are %d %d-byte cachelines\n", h->record_size_in_cachelines, h->cacheline_size); s = format (s, " files are %lld records long, %lld files\n", h->file_size_in_records, h->number_of_files); s = format (s, " %lld records total\n", h->number_of_records); return s; brief: s = format (s, "%s %lld records %lld files %lld records/file", h->file_basename, h->number_of_records, h->number_of_files, h->file_size_in_records); return s; } /** * @brief Process a complete maplog * * Reads the maplog header. Map and process all log segments in order. * Calls the callback function once per file with a record count. * * Note: if the file header isn't updated by calling * clib_maplog_close(), it will appear to have an infinite * number of records in an infinite number of files. * * So long as the callback function understands that possibility * - by simply ignoring NULL records - the scheme still * works... * * @param [in] file_basename Same basename supplied to clib_maplog_init * @param [in] fp_arg Callback function pointer */ int clib_maplog_process (char *file_basename, void *fp_arg) { clib_maplog_header_t _h, *h = &_h; int fd, rv = 0; u64 file_index; u64 file_size_in_bytes; u8 *header_filename, *this_filename = 0; u8 *file_baseva; int (*fp) (clib_maplog_header_t *, void *data, u64 count); u64 records_this_file, records_left; ASSERT (fp_arg); fp = fp_arg; header_filename = format (0, "%s_header%c", file_basename, 0); fd = open ((char *) header_filename, O_RDONLY, 0600); if (fd < 0) { clib_unix_warning ("open maplog header"); rv = -1; goto out; } rv = read (fd, h, sizeof (*h)); if (rv != sizeof (*h)) { clib_unix_warning ("read maplog header"); rv = -2; goto out; } (void) close (fd); fd = -1; file_size_in_bytes = h->file_size_in_records * h->record_size_in_cachelines * CLIB_CACHE_LINE_BYTES; records_left = h->number_of_records; for (file_index = 0; file_index < h->number_of_files; file_index++) { vec_reset_length (this_filename); this_filename = format (this_filename, "%s_%llu%c", file_basename, file_index, 0); fd = open ((char *) this_filename, O_RDONLY, 0600); if (fd < 0) { rv = -3; goto out; } file_baseva = mmap (0, file_size_in_bytes, PROT_READ, MAP_SHARED, fd, 0); (void) close (fd); fd = -1; if (file_baseva == (u8 *) MAP_FAILED) { clib_unix_warning ("mmap"); rv = -4; goto out; } records_this_file = (records_left > h->file_size_in_records) ? h->file_size_in_records : records_left; /* * Normal log, or a circular non-wrapped log, or a circular * wrapped log which happens to be exactly linear */ if (h->maplog_flag_circular == 0 || h->maplog_flag_wrapped == 0 || ((h->number_of_records % h->file_size_in_records) == 0)) (*fp) (h, file_baseva, records_this_file); else { /* "Normal" wrapped circular log */ u64 first_chunk_record_index = h->number_of_records & (h->file_size_in_records - 1); u64 first_chunk_number_of_records = records_this_file - first_chunk_record_index; u8 *chunk_baseva = file_baseva + first_chunk_record_index * h->record_size_in_cachelines * h->cacheline_size; (*fp) (h, chunk_baseva, first_chunk_number_of_records); (*fp) (h, file_baseva, records_this_file - first_chunk_number_of_records); } if (munmap (file_baseva, file_size_in_bytes) < 0) { clib_warning ("munmap"); rv = -5; /* but don't stop... */ } records_left -=