diff options
Diffstat (limited to 'include/linux/ftrace.h')
-rw-r--r-- | include/linux/ftrace.h | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index f4233b195dab..9212b017bc72 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -92,6 +92,7 @@ typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, * STUB - The ftrace_ops is just a place holder. * INITIALIZED - The ftrace_ops has already been initialized (first use time * register_ftrace_function() is called, it will initialized the ops) + * DELETED - The ops are being deleted, do not let them be registered again. */ enum { FTRACE_OPS_FL_ENABLED = 1 << 0, @@ -103,13 +104,26 @@ enum { FTRACE_OPS_FL_RECURSION_SAFE = 1 << 6, FTRACE_OPS_FL_STUB = 1 << 7, FTRACE_OPS_FL_INITIALIZED = 1 << 8, + FTRACE_OPS_FL_DELETED = 1 << 9, }; +/* + * Note, ftrace_ops can be referenced outside of RCU protection. + * (Although, for perf, the control ops prevent that). If ftrace_ops is + * allocated and not part of kernel core data, the unregistering of it will + * perform a scheduling on all CPUs to make sure that there are no more users. + * Depending on the load of the system that may take a bit of time. + * + * Any private data added must also take care not to be freed and if private + * data is added to a ftrace_ops that is in core code, the user of the + * ftrace_ops must perform a schedule_on_each_cpu() before freeing it. + */ struct ftrace_ops { ftrace_func_t func; struct ftrace_ops *next; unsigned long flags; int __percpu *disabled; + void *private; #ifdef CONFIG_DYNAMIC_FTRACE struct ftrace_hash *notrace_hash; struct ftrace_hash *filter_hash; @@ -285,7 +299,7 @@ extern void unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops); extern void unregister_ftrace_function_probe_all(char *glob); -extern int ftrace_text_reserved(void *start, void *end); +extern int ftrace_text_reserved(const void *start, const void *end); extern int ftrace_nr_registered_ops(void); @@ -316,12 +330,9 @@ enum { #define FTRACE_REF_MAX ((1UL << 29) - 1) struct dyn_ftrace { - union { - unsigned long ip; /* address of mcount call-site */ - struct dyn_ftrace *freelist; - }; + unsigned long ip; /* address of mcount call-site */ unsigned long flags; - struct dyn_arch_ftrace arch; + struct dyn_arch_ftrace arch; }; int ftrace_force_update(void); @@ -409,7 +420,7 @@ ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable); /* defined in arch */ extern int ftrace_ip_converted(unsigned long ip); -extern int ftrace_dyn_arch_init(void *data); +extern int ftrace_dyn_arch_init(void); extern void ftrace_replace_code(int enable); extern int ftrace_update_ftrace_func(ftrace_func_t func); extern void ftrace_caller(void); @@ -541,7 +552,7 @@ static inline __init int unregister_ftrace_command(char *cmd_name) { return -EINVAL; } -static inline int ftrace_text_reserved(void *start, void *end) +static inline int ftrace_text_reserved(const void *start, const void *end) { return 0; } |