diff options
author | Steven Rostedt <srostedt@redhat.com> | 2011-05-03 22:49:52 -0400 |
---|---|---|
committer | Steven Rostedt <rostedt@goodmis.org> | 2011-05-18 15:29:49 -0400 |
commit | 2b499381bc50ede01b3d8eab164ca2fad00655f0 (patch) | |
tree | 3140c277582b03b1645fffcb829763d62e2f01fa /kernel/trace/ftrace.c | |
parent | bd69c30b1d08032d97ab0dabd7a1eb7fb73ca2b2 (diff) |
ftrace: Have global_ops store the functions that are to be traced
This is a step towards each ops structure defining its own set
of functions to trace. As the current code with pid's and such
are specific to the global_ops, it is restructured to be used
with the global ops.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r-- | kernel/trace/ftrace.c | 69 |
1 files changed, 53 insertions, 16 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 8fef1d99bbb..dcce0bf9c84 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -91,6 +91,7 @@ static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub; ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub; ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub; +static struct ftrace_ops global_ops; /* * Traverse the ftrace_list, invoking all entries. The reason that we @@ -153,7 +154,7 @@ static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip) } #endif -static void update_ftrace_function(void) +static void update_global_ops(void) { ftrace_func_t func; @@ -173,6 +174,18 @@ static void update_ftrace_function(void) set_ftrace_pid_function(func); func = ftrace_pid_func; } + + global_ops.func = func; +} + +static void update_ftrace_function(void) +{ + ftrace_func_t func; + + update_global_ops(); + + func = global_ops.func; + #ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST ftrace_trace_function = func; #else @@ -181,24 +194,19 @@ static void update_ftrace_function(void) #endif } -static int __register_ftrace_function(struct ftrace_ops *ops) +static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) { - ops->next = ftrace_list; + ops->next = *list; /* * We are entering ops into the ftrace_list but another * CPU might be walking that list. We need to make sure * the ops->next pointer is valid before another CPU sees * the ops pointer included into the ftrace_list. */ - rcu_assign_pointer(ftrace_list, ops); - - if (ftrace_enabled) - update_ftrace_function(); - - return 0; + rcu_assign_pointer(*list, ops); } -static int __unregister_ftrace_function(struct ftrace_ops *ops) +static int remove_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops) { struct ftrace_ops **p; @@ -206,13 +214,12 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) * If we are removing the last function, then simply point * to the ftrace_stub. */ - if (ftrace_list == ops && ops->next == &ftrace_list_end) { - ftrace_trace_function = ftrace_stub; - ftrace_list = &ftrace_list_end; + if (*list == ops && ops->next == &ftrace_list_end) { + *list = &ftrace_list_end; return 0; } - for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next) + for (p = list; *p != &ftrace_list_end; p = &(*p)->next) if (*p == ops) break; @@ -220,7 +227,37 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) return -1; *p = (*p)->next; + return 0; +} + +static int __register_ftrace_function(struct ftrace_ops *ops) +{ + if (ftrace_disabled) + return -ENODEV; + + if (FTRACE_WARN_ON(ops == &global_ops)) + return -EINVAL; + + add_ftrace_ops(&ftrace_list, ops); + if (ftrace_enabled) + update_ftrace_function(); + + return 0; +} +static int __unregister_ftrace_function(struct ftrace_ops *ops) +{ + int ret; + + if (ftrace_disabled) + return -ENODEV; + + if (FTRACE_WARN_ON(ops == &global_ops)) + return -EINVAL; + + ret = remove_ftrace_ops(&ftrace_list, ops); + if (ret < 0) + return ret; if (ftrace_enabled) update_ftrace_function(); @@ -894,7 +931,7 @@ enum { FTRACE_OPS_FL_ENABLED = 1, }; -struct ftrace_ops global_ops = { +static struct ftrace_ops global_ops = { .func = ftrace_stub, .notrace_hash = EMPTY_HASH, .filter_hash = EMPTY_HASH, @@ -3263,7 +3300,7 @@ void __init ftrace_init(void) #else -struct ftrace_ops global_ops = { +static struct ftrace_ops global_ops = { .func = ftrace_stub, }; |