kernel/trace/ftrace.c

48 /* Flags that do not get reset */
190 	/* Probably not needed, but do it anyway */
225 	 * recursion safe and not dynamic and the arch supports passing ops,
503 /* not function graph compares against hits */
631 	 * We do not know the number of functions that exist because
999 			 * we still do not free memory.
1002 			     "Could not allocate stat file for cpu %d\n",
1011 			     "Could not register function stat for cpu %d\n",
1035  * It is not set when just updating a single ftrace_ops.
1107  * not return true for either core_kernel_text() or
1484 	 * hash and not in the notrace hash. Note, an empty hash is
1486 	 * notrace hash is considered not in the notrace hash.
1496  * the ops->func or not.
1499  * the filter_hash does not exist or is empty,
1501  * the ip is not in the ops->notrace_hash.
1515 	 * that wants regs, may be called without them. We can not
1534  * This is a double for. Do not use 'break' to break out of the loop,
1593  * internal tables to determine if the address belongs or not.
1646  * determine if the address belongs or not.
1752 			 * Update if the record is not in the notrace hash.
1762 			 * that are in the hash but not in the other hash.
1764 			 * If filter_hash is not set, then we are decrementing.
1827 			 * If not, we can stop recording them.
1935  * DIRECT ops does not have IPMODIFY flag, but we still need to check it
1967 	 * actions, we do not allow ftrace_ops to set all functions to new
2123  * EINVAL - if what is read at @ip is not what was expected
2207 	 * If enabling and the REGS flag does not match the REGS_EN, or
2208 	 * the TRAMP flag doesn't match the TRAMP_EN, then do not ignore
2224 		 * DIRECT and DIRECT_EN do not match, but only
2226 		 * count is something other than one, we do not
2229 		 * the count is not one, we need to clear it.
2353  * ftrace_update_record - set a record that now is tracing or not
2366  * ftrace_test_record - check if the record has been enabled or not
2465 	 * for single ops connected), then an ops that is not being
2490 		 * If the ops is not being added or modified, and it's
2576  * is not set, then it wants to convert to the normal callback.
2903  * arch_ftrace_update_code - modify the code to trace or not trace
2906  * Archs can override this function if it does not need to
2967  * not a module.
3030 	 * do not have trampolines. If they add them in the
3080 	 * Just warn in case of unbalance, no need to kill ftrace, it's not
3146 		 * the function tracers can be called where RCU is not watching
3147 		 * (like before user_exit()). We can not rely on the RCU
3156 		 * a CPU is not good enough to flush them. Calling
3618 		/* next must increment pos, and t_probe_start does not */
3719  * symbol found by kallsyms is not the function that the mcount/fentry
3723  * and if not, mark it disabled.
4272 		 * return 0. If it is not set, and the module doesn't match
4426 	/* We do not cache inverse filters */
4449 	/* We only care about modules that have not been loaded yet */
4640 	 * in the hash are not ftrace_func_entry type, we define it
4816 	/* We do not support '!' for function probes */
4964 		int not;
4967 						 &func_g.search, &not);
4970 		/* we do not support '!' for function probes */
4971 		if (WARN_ON(not))
5334  * not support ftrace_regs_caller but direct_call, use SAVE_ARGS so that it
5388  *  -ENODEV  - @ip does not point to a ftrace nop location (or not supported)
5410 	/* Make sure requested entries are not already registered.. */
5490  *  -EINVAL - The @ops object was not properly registered.
5584  *  -EINVAL - The @ops object was not properly registered.
5610  *  -EINVAL - The @ops object was not properly registered.
5679  * It can set the global filter only if ops were not initialized before.
5721  * ftrace_set_notrace - set a function to not trace in ftrace
5727  * Notrace Filters denote which functions should not be enabled when tracing
5758  * ftrace_set_global_notrace - set a function to not trace with global tracers
5763  * Notrace Filters denote which functions should not be enabled when tracing
5780 /* Used by function selftest to not test if filter is set */
5842 			printk(KERN_DEBUG "ftrace: function %s not "
6265 		 * the function tracers can be called where RCU is not watching
6266 		 * (like before user_exit()). We can not rely on the RCU
6291 	int not;
6295 					 &func_g.search, &not);
6314 			if (!not) {
6469 			 "[%d] %pS at %lx is not sorted with %pS at %lx\n", i,
6506 	 * modules can not be sorted at build time.
6582 	 * may execute, and the modification is not atomic.
6647  * If the ops does not trace the current record function, skip it.
6718 		 * Do not allow this rec to match again.
6750 	/* All the contents of mod_map are now not visible to readers */
6840 	 * The reason not to enable the record immediately is the
6858 		 * not part of this module, then skip this pg,
6866 			/* Clear all other flags. Should not be enabled anyway */
7100 	 * Do not allow this rec to match again.
7267 /* Do nothing if arch does not support this */
7374 		 * If any of the above fails then the op->func() is not executed.
7391  * the list function ignores the op parameter, we do not want any
7420  * If there's only one function registered but it does not support
7445  * are times that it should not. For example, if the ops does not
7454 	 * If the function does not handle recursion or needs to be RCU safe,
7890  * but in a not so nice way. If you need to simply kill ftrace
7901  * ftrace_is_dead - Test if ftrace is dead or not.