diff options
Diffstat (limited to 'src/vppinfra/maplog.h')
| -rw-r--r-- | src/vppinfra/maplog.h | 94 |
1 files changed, 79 insertions, 15 deletions
diff --git a/src/vppinfra/maplog.h b/src/vppinfra/maplog.h index 192dc22a71b..d1c23d20d29 100644 --- a/src/vppinfra/maplog.h +++ b/src/vppinfra/maplog.h @@ -16,9 +16,17 @@ #ifndef __included_maplog_h__ #define __included_maplog_h__ -/** \file +/** @file + @brief mmap-based thread-safe fixed-size record double-buffered logging. - mmap-based fixed-size record double-buffered logging + This scheme should be about as fast as practicable. By fiat, log + records are rounded to a multiple of CLIB_CACHE_LINE_BYTES. + Consumer code calls clib_maplog_get_entry(...) to obtain a pointer + to a log entry. + + We use an atomic ticket-counter to dole out log entries. Whichever + client thread crosses the double-buffer boundary is in charge of + replacing the log segment which just filled. */ #include <vppinfra/clib.h> @@ -30,37 +38,93 @@ #include <fcntl.h> #include <sys/mman.h> +/** Maplog log file header segment. In a separate file */ + +typedef struct +{ + u8 maplog_major_version; /**< library major version number */ + u8 maplog_minor_version; /**< library minor version number */ + u8 maplog_patch_version; /**< library patch version number */ + u8 pad; + u32 application_id; /**< application identifier */ + u8 application_major_version; /**< application major version number */ + u8 application_minor_version; /**< application minor version number */ + u8 application_patch_version; /**< application patch version number */ + u8 pad2; + u32 record_size_in_cachelines; /**< record size in cache lines */ + u32 cacheline_size; /**< cache line size */ + u64 file_size_in_records; /**< file size in records */ + u64 number_of_records; /**< number of records in entire log */ + u64 number_of_files; /**< number of files in entire log */ + u8 file_basename[256]; /**< file basename */ +} clib_maplog_header_t; + +#define MAPLOG_MAJOR_VERSION 1 +#define MAPLOG_MINOR_VERSION 0 +#define MAPLOG_PATCH_VERSION 0 + +/** Process-private main data structure */ + typedef struct { - /* rw: atomic ticket-counter, file index */ CLIB_CACHE_LINE_ALIGN_MARK (cacheline1); + /** rw cache line: atomic ticket-counter, file index */ volatile u64 next_record_index; - u64 file_size_in_records; /**< power of two */ - u32 log2_file_size_in_records; - volatile u32 current_file_index; - volatile u32 flags; + /** file size in records, rounded to a power of two */ + u64 file_size_in_records; + u32 log2_file_size_in_records; /**< lg file size in records */ + volatile u32 current_file_index; /**< current file index */ + volatile u32 flags; /**< flags, currently just "init" or not */ - /* ro: size parameters */ + /* read-mostly cache line: size parameters, file names, etc. */ CLIB_CACHE_LINE_ALIGN_MARK (cacheline2); - u32 record_size_in_cachelines; + u32 record_size_in_cachelines; /**< record size in cache lines */ /* double-buffered mmap'ed logfiles */ - volatile u8 *file_baseva[2]; - u8 *filenames[2]; + volatile u8 *file_baseva[2]; /**< active segment base addresses */ + u8 *filenames[2]; /**< active segment file names */ /* vector not c-string */ - u8 *file_basename; + u8 *file_basename; /**< basename, e.g. "/tmp/mylog" */ + u8 *header_filename; /**< log header file name */ } clib_maplog_main_t; -int clib_maplog_init (clib_maplog_main_t * mm, char *file_basename, - u64 file_size, u32 record_size_in_bytes); +/* flag bits */ +#define CLIB_MAPLOG_FLAG_INIT (1<<0) +/** log initialization structure */ +typedef struct +{ + clib_maplog_main_t *mm; /**< pointer to the main structure */ + char *file_basename; /**< file base name */ + u64 file_size_in_bytes; /**< file size in bytes */ + u32 record_size_in_bytes; /**< record size in bytes */ + u32 application_id; /**< application identifier */ + u8 application_major_version; /**< applcation major version number */ + u8 application_minor_version; /**< applcation minor version number */ + u8 application_patch_version; /**< applcation patch version number */ +} clib_maplog_init_args_t; + +/* function prototypes */ + +int clib_maplog_init (clib_maplog_init_args_t * ap); void clib_maplog_close (clib_maplog_main_t * mm); +int clib_maplog_process (char *file_basename, void *fp_arg); -#define CLIB_MAPLOG_FLAG_INIT (1<<0) +format_function_t format_maplog_header; u8 *_clib_maplog_get_entry_slowpath (clib_maplog_main_t * mm, u64 my_record_index); +/** + * @brief Obtain a log entry pointer + * + * Increments the atomic ticket counter, and returns a pointer to + * the newly-allocated log entry. The slowpath function replaces + * a full log segment with a new/fresh/empty log segment + * + * @param[in] mm maplog object pointer + * @return pointer to the allocated log entry + */ static inline void * clib_maplog_get_entry (clib_maplog_main_t * mm) { |