diff options
Diffstat (limited to 'tools/perf/util/dso.h')
-rw-r--r-- | tools/perf/util/dso.h | 50 |
1 files changed, 49 insertions, 1 deletions
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h index 38efe95..ad553ba 100644 --- a/tools/perf/util/dso.h +++ b/tools/perf/util/dso.h @@ -76,7 +76,6 @@ struct dso { struct list_head node; struct rb_root symbols[MAP__NR_TYPES]; struct rb_root symbol_names[MAP__NR_TYPES]; - struct rb_root cache; void *a2l; char *symsrc_filename; unsigned int a2l_fails; @@ -99,6 +98,15 @@ struct dso { const char *long_name; u16 long_name_len; u16 short_name_len; + + /* dso data file */ + struct { + struct rb_root cache; + int fd; + size_t file_size; + struct list_head open_entry; + } data; + char name[0]; }; @@ -141,7 +149,47 @@ char dso__symtab_origin(const struct dso *dso); int dso__read_binary_type_filename(const struct dso *dso, enum dso_binary_type type, char *root_dir, char *filename, size_t size); +/* + * The dso__data_* external interface provides following functions: + * dso__data_fd + * dso__data_close + * dso__data_read_offset + * dso__data_read_addr + * + * Please refer to the dso.c object code for each function and + * arguments documentation. Following text tries to explain the + * dso file descriptor caching. + * + * The dso__data* interface allows caching of opened file descriptors + * to speed up the dso data accesses. The idea is to leave the file + * descriptor opened ideally for the whole life of the dso object. + * + * The current usage of the dso__data_* interface is as follows: + * + * Get DSO's fd: + * int fd = dso__data_fd(dso, machine); + * USE 'fd' SOMEHOW + * + * Read DSO's data: + * n = dso__data_read_offset(dso_0, &machine, 0, buf, BUFSIZE); + * n = dso__data_read_addr(dso_0, &machine, 0, buf, BUFSIZE); + * + * Eventually close DSO's fd: + * dso__data_close(dso); + * + * It is not necessary to close the DSO object data file. Each time new + * DSO data file is opened, the limit (RLIMIT_NOFILE/2) is checked. Once + * it is crossed, the oldest opened DSO object is closed. + * + * The dso__delete function calls close_dso function to ensure the + * data file descriptor gets closed/unmapped before the dso object + * is freed. + * + * TODO +*/ int dso__data_fd(struct dso *dso, struct machine *machine); +void dso__data_close(struct dso *dso); + ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine, u64 offset, u8 *data, ssize_t size); ssize_t dso__data_read_addr(struct dso *dso, struct map *map, |