From e16b35ddb840788e023fac2482b61c0b6bf98057 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Tue, 4 Apr 2017 14:46:56 -0400 Subject: [PATCH] ftrace: Add helper function ftrace_hash_move_and_update_ops() The processes of updating a ops filter_hash is a bit complex, and requires setting up an old hash to perform the update. This is done exactly the same in two locations for the same reasons. Create a helper function that does it in one place. Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/ftrace.c | 105 +++++++++++++++++++++--------------------- 1 file changed, 53 insertions(+), 52 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f7fcab8f3aa1..5c8d8eea9e7c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3674,6 +3674,56 @@ ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) return match_records(hash, buff, len, NULL); } +static void ftrace_ops_update_code(struct ftrace_ops *ops, + struct ftrace_ops_hash *old_hash) +{ + struct ftrace_ops *op; + + if (!ftrace_enabled) + return; + + if (ops->flags & FTRACE_OPS_FL_ENABLED) { + ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); + return; + } + + /* + * If this is the shared global_ops filter, then we need to + * check if there is another ops that shares it, is enabled. + * If so, we still need to run the modify code. + */ + if (ops->func_hash != &global_ops.local_hash) + return; + + do_for_each_ftrace_op(op, ftrace_ops_list) { + if (op->func_hash == &global_ops.local_hash && + op->flags & FTRACE_OPS_FL_ENABLED) { + ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); + /* Only need to do this once */ + return; + } + } while_for_each_ftrace_op(op); +} + +static int ftrace_hash_move_and_update_ops(struct ftrace_ops *ops, + struct ftrace_hash **orig_hash, + struct ftrace_hash *hash, + int enable) +{ + struct ftrace_ops_hash old_hash_ops; + struct ftrace_hash *old_hash; + int ret; + + old_hash = *orig_hash; + old_hash_ops.filter_hash = ops->func_hash->filter_hash; + old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; + ret = ftrace_hash_move(ops, enable, orig_hash, hash); + if (!ret) { + ftrace_ops_update_code(ops, &old_hash_ops); + free_ftrace_hash_rcu(old_hash); + } + return ret; +} /* * We register the module command as a template to show others how @@ -4306,44 +4356,11 @@ ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) return add_hash_entry(hash, ip); } -static void ftrace_ops_update_code(struct ftrace_ops *ops, - struct ftrace_ops_hash *old_hash) -{ - struct ftrace_ops *op; - - if (!ftrace_enabled) - return; - - if (ops->flags & FTRACE_OPS_FL_ENABLED) { - ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash); - return; - } - - /* - * If this is the shared global_ops filter, then we need to - * check if there is another ops that shares it, is enabled. - * If so, we still need to run the modify code. - */ - if (ops->func_hash != &global_ops.local_hash) - return; - - do_for_each_ftrace_op(op, ftrace_ops_list) { - if (op->func_hash == &global_ops.local_hash && - op->flags & FTRACE_OPS_FL_ENABLED) { - ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash); - /* Only need to do this once */ - return; - } - } while_for_each_ftrace_op(op); -} - static int ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, unsigned long ip, int remove, int reset, int enable) { struct ftrace_hash **orig_hash; - struct ftrace_ops_hash old_hash_ops; - struct ftrace_hash *old_hash; struct ftrace_hash *hash; int ret; @@ -4378,14 +4395,7 @@ ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len, } mutex_lock(&ftrace_lock); - old_hash = *orig_hash; - old_hash_ops.filter_hash = ops->func_hash->filter_hash; - old_hash_ops.notrace_hash = ops->func_hash->notrace_hash; - ret = ftrace_hash_move(ops, enable, orig_hash, hash); - if (!ret) { - ftrace_ops_update_code(ops, &old_hash_ops); - free_ftrace_hash_rcu(old_hash); - } + ret = ftrace_hash_move_and_update_ops(ops, orig_hash, hash, enable); mutex_unlock(&ftrace_lock); out_regex_unlock: @@ -4624,10 +4634,8 @@ static void __init set_ftrace_early_filters(void) int ftrace_regex_release(struct inode *inode, struct file *file) { struct seq_file *m = (struct seq_file *)file->private_data; - struct ftrace_ops_hash old_hash_ops; struct ftrace_iterator *iter; struct ftrace_hash **orig_hash; - struct ftrace_hash *old_hash; struct trace_parser *parser; int filter_hash; int ret; @@ -4657,15 +4665,8 @@ int ftrace_regex_release(struct inode *inode, struct file *file) orig_hash = &iter->ops->func_hash->notrace_hash; mutex_lock(&ftrace_lock); - old_hash = *orig_hash; - old_hash_ops.filter_hash = iter->ops->func_hash->filter_hash; - old_hash_ops.notrace_hash = iter->ops->func_hash->notrace_hash; - ret = ftrace_hash_move(iter->ops, filter_hash, - orig_hash, iter->hash); - if (!ret) { - ftrace_ops_update_code(iter->ops, &old_hash_ops); - free_ftrace_hash_rcu(old_hash); - } + ret = ftrace_hash_move_and_update_ops(iter->ops, orig_hash, + iter->hash, filter_hash); mutex_unlock(&ftrace_lock); } else { /* For read only, the hash is the ops hash */ -- 2.20.1