diff options
Diffstat (limited to 'kernel/trace/ftrace.c')
| -rw-r--r-- | kernel/trace/ftrace.c | 146 |
1 files changed, 144 insertions, 2 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index d7297e866e4a..86dbbfb353db 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5675,6 +5675,21 @@ static int ftrace_process_locs(struct module *mod, return ret; } +struct ftrace_mod_func { + struct list_head list; + char *name; + unsigned long ip; + unsigned int size; +}; + +struct ftrace_mod_map { + struct list_head list; + struct module *mod; + unsigned long start_addr; + unsigned long end_addr; + struct list_head funcs; +}; + #ifdef CONFIG_MODULES #define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next) @@ -5868,9 +5883,123 @@ void ftrace_module_init(struct module *mod) ftrace_process_locs(mod, mod->ftrace_callsites, mod->ftrace_callsites + mod->num_ftrace_callsites); } + +static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, + struct dyn_ftrace *rec) +{ + struct ftrace_mod_func *mod_func; + unsigned long symsize; + unsigned long offset; + char str[KSYM_SYMBOL_LEN]; + char *modname; + const char *ret; + + ret = kallsyms_lookup(rec->ip, &symsize, &offset, &modname, str); + if (!ret) + return; + + mod_func = kmalloc(sizeof(*mod_func), GFP_KERNEL); + if (!mod_func) + return; + + mod_func->name = kstrdup(str, GFP_KERNEL); + if (!mod_func->name) { + kfree(mod_func); + return; + } + + mod_func->ip = rec->ip - offset; + mod_func->size = symsize; + + list_add_rcu(&mod_func->list, &mod_map->funcs); +} + +static LIST_HEAD(ftrace_mod_maps); + +static struct ftrace_mod_map * +allocate_ftrace_mod_map(struct module *mod, + unsigned long start, unsigned long end) +{ + struct ftrace_mod_map *mod_map; + + mod_map = kmalloc(sizeof(*mod_map), GFP_KERNEL); + if (!mod_map) + return NULL; + + mod_map->mod = mod; + mod_map->start_addr = start; + mod_map->end_addr = end; + + INIT_LIST_HEAD_RCU(&mod_map->funcs); + + list_add_rcu(&mod_map->list, &ftrace_mod_maps); + + return mod_map; +} + +static const char * +ftrace_func_address_lookup(struct ftrace_mod_map *mod_map, + unsigned long addr, unsigned long *size, + unsigned long *off, char *sym) +{ + struct ftrace_mod_func *found_func = NULL; + struct ftrace_mod_func *mod_func; + + list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) { + if (addr >= mod_func->ip && + addr < mod_func->ip + mod_func->size) { + found_func = mod_func; + break; + } + } + + if (found_func) { + if (size) + *size = found_func->size; + if (off) + *off = addr - found_func->ip; + if (sym) + strlcpy(sym, found_func->name, KSYM_NAME_LEN); + + return found_func->name; + } + + return NULL; +} + +const char * +ftrace_mod_address_lookup(unsigned long addr, unsigned long *size, + unsigned long *off, char **modname, char *sym) +{ + struct ftrace_mod_map *mod_map; + const char *ret = NULL; + + preempt_disable(); + list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) { + ret = ftrace_func_address_lookup(mod_map, addr, size, off, sym); + if (ret) { + if (modname) + *modname = mod_map->mod->name; + break; + } + } + preempt_enable(); + + return ret; +} + +#else +static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map, + struct dyn_ftrace *rec) { } +static inline struct ftrace_mod_map * +allocate_ftrace_mod_map(struct module *mod, + unsigned long start, unsigned long end) +{ + return NULL; +} #endif /* CONFIG_MODULES */ -void ftrace_free_mem(void *start_ptr, void *end_ptr) +void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) { unsigned long start = (unsigned long)(start_ptr); unsigned long end = (unsigned long)(end_ptr); @@ -5878,6 +6007,7 @@ void ftrace_free_mem(void *start_ptr, void *end_ptr) struct ftrace_page *pg; struct dyn_ftrace *rec; struct dyn_ftrace key; + struct ftrace_mod_map *mod_map = NULL; int order; key.ip = start; @@ -5885,6 +6015,14 @@ void ftrace_free_mem(void *start_ptr, void *end_ptr) mutex_lock(&ftrace_lock); + /* + * If we are freeing module init memory, then check if + * any tracer is active. If so, we need to save a mapping of + * the module functions being freed with the address. + */ + if (mod && ftrace_ops_list != &ftrace_list_end) + mod_map = allocate_ftrace_mod_map(mod, start, end); + for (pg = ftrace_pages_start; pg; last_pg = &pg->next, pg = *last_pg) { if (end < pg->records[0].ip || start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE)) @@ -5895,6 +6033,10 @@ void ftrace_free_mem(void *start_ptr, void *end_ptr) ftrace_cmp_recs); if (!rec) continue; + + if (mod_map) + save_ftrace_mod_rec(mod_map, rec); + pg->index--; ftrace_update_tot_cnt--; if (!pg->index) { @@ -5920,7 +6062,7 @@ void __init ftrace_free_init_mem(void) void *start = (void *)(&__init_begin); void *end = (void *)(&__init_end); - ftrace_free_mem(start, end); + ftrace_free_mem(NULL, start, end); } void __init ftrace_init(void) |