diff options
| author | Steven Rostedt (Red Hat) <rostedt@goodmis.org> | 2014-08-18 19:21:08 +0200 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2014-08-22 19:21:14 +0200 |
| commit | 84261912ebee41269004e8a9f3614ba38ef6b206 (patch) | |
| tree | 26a01f98f3c14d299570012d5aa5655794d3a9e6 /kernel | |
| parent | ftrace: Allow ftrace_ops to use the hashes from other ops (diff) | |
| download | linux-84261912ebee41269004e8a9f3614ba38ef6b206.tar.xz linux-84261912ebee41269004e8a9f3614ba38ef6b206.zip | |
ftrace: Update all ftrace_ops for a ftrace_hash_ops update
When updating what an ftrace_ops traces, if it is registered (that is,
actively tracing), and that ftrace_ops uses the shared global_ops
local_hash, then we need to update all tracers that are active and
also share the global_ops' ftrace_hash_ops.
Cc: stable@vger.kernel.org # 3.16 (apply after 3.17-rc4 is out)
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/ftrace.c | 43 |
1 files changed, 39 insertions, 4 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index c92757adba79..37f9e90d241c 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1292,9 +1292,9 @@ alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash) } static void -ftrace_hash_rec_disable(struct ftrace_ops *ops, int filter_hash); +ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash); static void -ftrace_hash_rec_enable(struct ftrace_ops *ops, int filter_hash); +ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash); static int ftrace_hash_move(struct ftrace_ops *ops, int enable, @@ -1346,13 +1346,13 @@ update: * Remove the current set, update the hash and add * them back. */ - ftrace_hash_rec_disable(ops, enable); + ftrace_hash_rec_disable_modify(ops, enable); old_hash = *dst; rcu_assign_pointer(*dst, new_hash); free_ftrace_hash_rcu(old_hash); - ftrace_hash_rec_enable(ops, enable); + ftrace_hash_rec_enable_modify(ops, enable); return 0; } @@ -1686,6 +1686,41 @@ static void ftrace_hash_rec_enable(struct ftrace_ops *ops, __ftrace_hash_rec_update(ops, filter_hash, 1); } +static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops, + int filter_hash, int inc) +{ + struct ftrace_ops *op; + + __ftrace_hash_rec_update(ops, filter_hash, inc); + + if (ops->func_hash != &global_ops.local_hash) + return; + + /* + * If the ops shares the global_ops hash, then we need to update + * all ops that are enabled and use this hash. + */ + do_for_each_ftrace_op(op, ftrace_ops_list) { + /* Already done */ + if (op == ops) + continue; + if (op->func_hash == &global_ops.local_hash) + __ftrace_hash_rec_update(op, filter_hash, inc); + } while_for_each_ftrace_op(op); +} + +static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, + int filter_hash) +{ + ftrace_hash_rec_update_modify(ops, filter_hash, 0); +} + +static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, + int filter_hash) +{ + ftrace_hash_rec_update_modify(ops, filter_hash, 1); +} + static void print_ip_ins(const char *fmt, unsigned char *p) { int i; |