#define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops)
#endif
+/*
+ * Traverse the ftrace_global_list, invoking all entries. The reason that we
+ * can use rcu_dereference_raw() is that elements removed from this list
+ * are simply leaked, so there is no need to interact with a grace-period
+ * mechanism. The rcu_dereference_raw() calls are needed to handle
+ * concurrent insertions into the ftrace_global_list.
+ *
+ * Silly Alpha and silly pointer-speculation compiler optimizations!
+ */
+#define do_for_each_ftrace_op(op, list) \
+ op = rcu_dereference_raw(list); \
+ do
+
+/*
+ * Optimized for just a single item in the list (as that is the normal case).
+ */
+#define while_for_each_ftrace_op(op) \
+ while (likely(op = rcu_dereference_raw((op)->next)) && \
+ unlikely((op) != &ftrace_list_end))
+
/**
* ftrace_nr_registered_ops - return number of ops registered
*
return cnt;
}
-/*
- * Traverse the ftrace_global_list, invoking all entries. The reason that we
- * can use rcu_dereference_raw() is that elements removed from this list
- * are simply leaked, so there is no need to interact with a grace-period
- * mechanism. The rcu_dereference_raw() calls are needed to handle
- * concurrent insertions into the ftrace_global_list.
- *
- * Silly Alpha and silly pointer-speculation compiler optimizations!
- */
static void
ftrace_global_list_func(unsigned long ip, unsigned long parent_ip,
struct ftrace_ops *op, struct pt_regs *regs)
{
- if (unlikely(trace_recursion_test(TRACE_GLOBAL_BIT)))
+ int bit;
+
+ bit = trace_test_and_set_recursion(TRACE_GLOBAL_START, TRACE_GLOBAL_MAX);
+ if (bit < 0)
return;
- trace_recursion_set(TRACE_GLOBAL_BIT);
- op = rcu_dereference_raw(ftrace_global_list); /*see above*/
- while (op != &ftrace_list_end) {
+ do_for_each_ftrace_op(op, ftrace_global_list) {
op->func(ip, parent_ip, op, regs);
- op = rcu_dereference_raw(op->next); /*see above*/
- };
- trace_recursion_clear(TRACE_GLOBAL_BIT);
+ } while_for_each_ftrace_op(op);
+
+ trace_clear_recursion(bit);
}
static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
* registered callers.
*/
if (ftrace_global_list == &ftrace_list_end ||
- ftrace_global_list->next == &ftrace_list_end)
+ ftrace_global_list->next == &ftrace_list_end) {
func = ftrace_global_list->func;
- else
+ /*
+ * As we are calling the function directly.
+ * If it does not have recursion protection,
+ * the function_trace_op needs to be updated
+ * accordingly.
+ */
+ if (ftrace_global_list->flags & FTRACE_OPS_FL_RECURSION_SAFE)
+ global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
+ else
+ global_ops.flags &= ~FTRACE_OPS_FL_RECURSION_SAFE;
+ } else {
func = ftrace_global_list_func;
+ /* The list has its own recursion protection. */
+ global_ops.flags |= FTRACE_OPS_FL_RECURSION_SAFE;
+ }
+
/* If we filter on pids, update to use the pid function */
if (!list_empty(&ftrace_pids)) {
if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK)
return -EINVAL;
-#ifndef ARCH_SUPPORTS_FTRACE_SAVE_REGS
+#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS
/*
* If the ftrace_ops specifies SAVE_REGS, then it only can be used
* if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set.
unsigned long flags;
unsigned long ip;
void *data;
- struct rcu_head rcu;
+ struct list_head free_list;
};
struct ftrace_func_entry {
}
-static void ftrace_free_entry_rcu(struct rcu_head *rhp)
+static void ftrace_free_entry(struct ftrace_func_probe *entry)
{
- struct ftrace_func_probe *entry =
- container_of(rhp, struct ftrace_func_probe, rcu);
-
if (entry->ops->free)
- entry->ops->free(&entry->data);
+ entry->ops->free(entry->ops, entry->ip, &entry->data);
kfree(entry);
}
-
int
register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
void *data)
{
struct ftrace_func_probe *entry;
+ struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash;
+ struct ftrace_hash *hash;
struct ftrace_page *pg;
struct dyn_ftrace *rec;
int type, len, not;
unsigned long key;
int count = 0;
char *search;
+ int ret;
type = filter_parse_regex(glob, strlen(glob), &search, ¬);
len = strlen(search);
mutex_lock(&ftrace_lock);
- if (unlikely(ftrace_disabled))
+ hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
+ if (!hash) {
+ count = -ENOMEM;
+ goto out_unlock;
+ }
+
+ if (unlikely(ftrace_disabled)) {
+ count = -ENODEV;
goto out_unlock;
+ }
do_for_each_ftrace_rec(pg, rec) {
* for each function we find. We call the callback
* to give the caller an opportunity to do so.
*/
- if (ops->callback) {
- if (ops->callback(rec->ip, &entry->data) < 0) {
+ if (ops->init) {
+ if (ops->init(ops, rec->ip, &entry->data) < 0) {
/* caller does not like this func */
kfree(entry);
continue;
}
}
+ ret = enter_record(hash, rec, 0);
+ if (ret < 0) {
+ kfree(entry);
+ count = ret;
+ goto out_unlock;
+ }
+
entry->ops = ops;
entry->ip = rec->ip;
hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]);
} while_for_each_ftrace_rec();
+
+ ret = ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+ if (ret < 0)
+ count = ret;
+
__enable_ftrace_function_probe();
out_unlock:
mutex_unlock(&ftrace_lock);
+ free_ftrace_hash(hash);
return count;
}
__unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
void *data, int flags)
{
+ struct ftrace_func_entry *rec_entry;
struct ftrace_func_probe *entry;
+ struct ftrace_func_probe *p;
+ struct ftrace_hash **orig_hash = &trace_probe_ops.filter_hash;
+ struct list_head free_list;
+ struct ftrace_hash *hash;
struct hlist_node *n, *tmp;
char str[KSYM_SYMBOL_LEN];
int type = MATCH_FULL;
}
mutex_lock(&ftrace_lock);
+
+ hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
+ if (!hash)
+ /* Hmm, should report this somehow */
+ goto out_unlock;
+
+ INIT_LIST_HEAD(&free_list);
+
for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
struct hlist_head *hhd = &ftrace_func_hash[i];
continue;
}
- hlist_del(&entry->node);
- call_rcu(&entry->rcu, ftrace_free_entry_rcu);
+ rec_entry = ftrace_lookup_ip(hash, entry->ip);
+ /* It is possible more than one entry had this ip */
+ if (rec_entry)
+ free_hash_entry(hash, rec_entry);
+
+ hlist_del_rcu(&entry->node);
+ list_add(&entry->free_list, &free_list);
}
}
__disable_ftrace_function_probe();
+ /*
+ * Remove after the disable is called. Otherwise, if the last
+ * probe is removed, a null hash means *all enabled*.
+ */
+ ftrace_hash_move(&trace_probe_ops, 1, orig_hash, hash);
+ synchronize_sched();
+ list_for_each_entry_safe(entry, p, &free_list, free_list) {
+ list_del(&entry->free_list);
+ ftrace_free_entry(entry);
+ }
+
+ out_unlock:
mutex_unlock(&ftrace_lock);
+ free_ftrace_hash(hash);
}
void
ftrace_process_locs(mod, start, end);
}
-static int ftrace_module_notify(struct notifier_block *self,
- unsigned long val, void *data)
+static int ftrace_module_notify_enter(struct notifier_block *self,
+ unsigned long val, void *data)
{
struct module *mod = data;
- switch (val) {
- case MODULE_STATE_COMING:
+ if (val == MODULE_STATE_COMING)
ftrace_init_module(mod, mod->ftrace_callsites,
mod->ftrace_callsites +
mod->num_ftrace_callsites);
- break;
- case MODULE_STATE_GOING:
+ return 0;
+}
+
+static int ftrace_module_notify_exit(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct module *mod = data;
+
+ if (val == MODULE_STATE_GOING)
ftrace_release_mod(mod);
- break;
- }
return 0;
}
#else
-static int ftrace_module_notify(struct notifier_block *self,
- unsigned long val, void *data)
+static int ftrace_module_notify_enter(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ return 0;
+}
+static int ftrace_module_notify_exit(struct notifier_block *self,
+ unsigned long val, void *data)
{
return 0;
}
#endif /* CONFIG_MODULES */
-struct notifier_block ftrace_module_nb = {
- .notifier_call = ftrace_module_notify,
+struct notifier_block ftrace_module_enter_nb = {
+ .notifier_call = ftrace_module_notify_enter,
.priority = INT_MAX, /* Run before anything that can use kprobes */
};
+struct notifier_block ftrace_module_exit_nb = {
+ .notifier_call = ftrace_module_notify_exit,
+ .priority = INT_MIN, /* Run after anything that can remove kprobes */
+};
+
extern unsigned long __start_mcount_loc[];
extern unsigned long __stop_mcount_loc[];
__start_mcount_loc,
__stop_mcount_loc);
- ret = register_module_notifier(&ftrace_module_nb);
+ ret = register_module_notifier(&ftrace_module_enter_nb);
if (ret)
- pr_warning("Failed to register trace ftrace module notifier\n");
+ pr_warning("Failed to register trace ftrace module enter notifier\n");
+
+ ret = register_module_notifier(&ftrace_module_exit_nb);
+ if (ret)
+ pr_warning("Failed to register trace ftrace module exit notifier\n");
set_ftrace_early_filters();
*/
preempt_disable_notrace();
trace_recursion_set(TRACE_CONTROL_BIT);
- op = rcu_dereference_raw(ftrace_control_list);
- while (op != &ftrace_list_end) {
+ do_for_each_ftrace_op(op, ftrace_control_list) {
if (!ftrace_function_local_disabled(op) &&
ftrace_ops_test(op, ip))
op->func(ip, parent_ip, op, regs);
-
- op = rcu_dereference_raw(op->next);
- };
+ } while_for_each_ftrace_op(op);
trace_recursion_clear(TRACE_CONTROL_BIT);
preempt_enable_notrace();
}
struct ftrace_ops *ignored, struct pt_regs *regs)
{
struct ftrace_ops *op;
+ int bit;
if (function_trace_stop)
return;
- if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT)))
+ bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
+ if (bit < 0)
return;
- trace_recursion_set(TRACE_INTERNAL_BIT);
/*
* Some of the ops may be dynamically allocated,
* they must be freed after a synchronize_sched().
*/
preempt_disable_notrace();
- op = rcu_dereference_raw(ftrace_ops_list);
- while (op != &ftrace_list_end) {
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
if (ftrace_ops_test(op, ip))
op->func(ip, parent_ip, op, regs);
- op = rcu_dereference_raw(op->next);
- };
+ } while_for_each_ftrace_op(op);
preempt_enable_notrace();
- trace_recursion_clear(TRACE_INTERNAL_BIT);
+ trace_clear_recursion(bit);
}
/*
* Archs are to support both the regs and ftrace_ops at the same time.
* If they support ftrace_ops, it is assumed they support regs.
* If call backs want to use regs, they must either check for regs
- * being NULL, or ARCH_SUPPORTS_FTRACE_SAVE_REGS.
- * Note, ARCH_SUPPORT_SAVE_REGS expects a full regs to be saved.
+ * being NULL, or CONFIG_DYNAMIC_FTRACE_WITH_REGS.
+ * Note, CONFIG_DYNAMIC_FTRACE_WITH_REGS expects a full regs to be saved.
* An architecture can pass partial regs with ftrace_ops and still
* set the ARCH_SUPPORT_FTARCE_OPS.
*/
projects / ~andy / linux / blobdiff