summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJoel Fernandes <joelaf@google.com>2016-11-15 12:31:20 -0800
committerKees Cook <keescook@chromium.org>2016-11-15 16:34:30 -0800
commitd032ae8921ea792c1e6b2abb44022b2403f651f6 (patch)
tree43e227118b9111e27a0df4f199e6632d552311dc
parenta5d23b956cabd5931d4aff07573cd9d053bacd74 (diff)
ftrace: Provide API to use global filtering for ftrace ops
Currently the global_ops filtering hash is not available to outside users registering for function tracing. Provide an API for those users to be able to choose global filtering. This is in preparation for pstore's ftrace feature to be able to use the global filters. Suggested-by: Steven Rostedt <rostedt@goodmis.org> Cc: Anton Vorontsov <anton@enomsg.org> Cc: Colin Cross <ccross@android.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Joel Fernandes <joelaf@google.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Kees Cook <keescook@chromium.org>
-rw-r--r--include/linux/ftrace.h2
-rw-r--r--kernel/trace/ftrace.c17
2 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index b3d34d3e0e7e..d4a884db16a3 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -398,6 +398,7 @@ int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
void ftrace_free_filter(struct ftrace_ops *ops);
+void ftrace_ops_set_global_filter(struct ftrace_ops *ops);
int register_ftrace_command(struct ftrace_func_command *cmd);
int unregister_ftrace_command(struct ftrace_func_command *cmd);
@@ -645,6 +646,7 @@ static inline unsigned long ftrace_location(unsigned long ip)
#define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; })
#define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; })
#define ftrace_free_filter(ops) do { } while (0)
+#define ftrace_ops_set_global_filter(ops) do { } while (0)
static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos) { return -ENODEV; }
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 2050a7652a86..89d46e1c9302 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -4239,6 +4239,23 @@ int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
}
EXPORT_SYMBOL_GPL(ftrace_set_filter_ip);
+/**
+ * ftrace_ops_set_global_filter - setup ops to use global filters
+ * @ops - the ops which will use the global filters
+ *
+ * ftrace users who need global function trace filtering should call this.
+ * It can set the global filter only if ops were not initialized before.
+ */
+void ftrace_ops_set_global_filter(struct ftrace_ops *ops)
+{
+ if (ops->flags & FTRACE_OPS_FL_INITIALIZED)
+ return;
+
+ ftrace_ops_init(ops);
+ ops->func_hash = &global_ops.local_hash;
+}
+EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter);
+
static int
ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
int reset, int enable)