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-rw-r--r--Documentation/trace/ftrace-uses.rst60
1 files changed, 30 insertions, 30 deletions
diff --git a/Documentation/trace/ftrace-uses.rst b/Documentation/trace/ftrace-uses.rst
index 8494a801d341..3aed560a12ee 100644
--- a/Documentation/trace/ftrace-uses.rst
+++ b/Documentation/trace/ftrace-uses.rst
@@ -42,9 +42,9 @@ as well as what protections the callback will perform and not require
ftrace to handle.
There is only one field that is needed to be set when registering
-an ftrace_ops with ftrace::
+an ftrace_ops with ftrace:
-.. code-block: c
+.. code-block:: c
struct ftrace_ops ops = {
.func = my_callback_func,
@@ -81,12 +81,12 @@ may take some time to finish.
The callback function
=====================
-The prototype of the callback function is as follows (as of v4.14)::
+The prototype of the callback function is as follows (as of v4.14):
-.. code-block: c
+.. code-block:: c
- void callback_func(unsigned long ip, unsigned long parent_ip,
- struct ftrace_ops *op, struct pt_regs *regs);
+ void callback_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs);
@ip
This is the instruction pointer of the function that is being traced.
@@ -176,10 +176,10 @@ Filtering which functions to trace
If a callback is only to be called from specific functions, a filter must be
set up. The filters are added by name, or ip if it is known.
-.. code-block: c
+.. code-block:: c
- int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
- int len, int reset);
+ int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
+ int len, int reset);
@ops
The ops to set the filter with
@@ -202,9 +202,9 @@ See Filter Commands in :file:`Documentation/trace/ftrace.txt`.
To just trace the schedule function::
-.. code-block: c
+.. code-block:: c
- ret = ftrace_set_filter(&ops, "schedule", strlen("schedule"), 0);
+ ret = ftrace_set_filter(&ops, "schedule", strlen("schedule"), 0);
To add more functions, call the ftrace_set_filter() more than once with the
@reset parameter set to zero. To remove the current filter set and replace it
@@ -212,17 +212,17 @@ with new functions defined by @buf, have @reset be non-zero.
To remove all the filtered functions and trace all functions::
-.. code-block: c
+.. code-block:: c
- ret = ftrace_set_filter(&ops, NULL, 0, 1);
+ ret = ftrace_set_filter(&ops, NULL, 0, 1);
Sometimes more than one function has the same name. To trace just a specific
function in this case, ftrace_set_filter_ip() can be used.
-.. code-block: c
+.. code-block:: c
- ret = ftrace_set_filter_ip(&ops, ip, 0, 0);
+ ret = ftrace_set_filter_ip(&ops, ip, 0, 0);
Although the ip must be the address where the call to fentry or mcount is
located in the function. This function is used by perf and kprobes that
@@ -237,10 +237,10 @@ be called by any function.
An empty "notrace" list means to allow all functions defined by the filter
to be traced.
-.. code-block: c
+.. code-block:: c
- int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
- int len, int reset);
+ int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
+ int len, int reset);
This takes the same parameters as ftrace_set_filter() but will add the
functions it finds to not be traced. This is a separate list from the
@@ -251,7 +251,7 @@ that match @buf to it.
Clearing the "notrace" list is the same as clearing the filter list
-.. code-block: c
+.. code-block:: c
ret = ftrace_set_notrace(&ops, NULL, 0, 1);
@@ -264,29 +264,29 @@ If a filter is in place, and the @reset is non-zero, and @buf contains a
matching glob to functions, the switch will happen during the time of
the ftrace_set_filter() call. At no time will all functions call the callback.
-.. code-block: c
+.. code-block:: c
- ftrace_set_filter(&ops, "schedule", strlen("schedule"), 1);
+ ftrace_set_filter(&ops, "schedule", strlen("schedule"), 1);
- register_ftrace_function(&ops);
+ register_ftrace_function(&ops);
- msleep(10);
+ msleep(10);
- ftrace_set_filter(&ops, "try_to_wake_up", strlen("try_to_wake_up"), 1);
+ ftrace_set_filter(&ops, "try_to_wake_up", strlen("try_to_wake_up"), 1);
is not the same as:
-.. code-block: c
+.. code-block:: c
- ftrace_set_filter(&ops, "schedule", strlen("schedule"), 1);
+ ftrace_set_filter(&ops, "schedule", strlen("schedule"), 1);
- register_ftrace_function(&ops);
+ register_ftrace_function(&ops);
- msleep(10);
+ msleep(10);
- ftrace_set_filter(&ops, NULL, 0, 1);
+ ftrace_set_filter(&ops, NULL, 0, 1);
- ftrace_set_filter(&ops, "try_to_wake_up", strlen("try_to_wake_up"), 0);
+ ftrace_set_filter(&ops, "try_to_wake_up", strlen("try_to_wake_up"), 0);
As the latter will have a short time where all functions will call
the callback, between the time of the reset, and the time of the