![Steven Rostedt (Red Hat)](/assets/img/avatar_default.png)
A race exists between module loading and enabling of function tracer. CPU 1 CPU 2 ----- ----- load_module() module->state = MODULE_STATE_COMING register_ftrace_function() mutex_lock(&ftrace_lock); ftrace_startup() update_ftrace_function(); ftrace_arch_code_modify_prepare() set_all_module_text_rw(); <enables-ftrace> ftrace_arch_code_modify_post_process() set_all_module_text_ro(); [ here all module text is set to RO, including the module that is loading!! ] blocking_notifier_call_chain(MODULE_STATE_COMING); ftrace_init_module() [ tries to modify code, but it's RO, and fails! ftrace_bug() is called] When this race happens, ftrace_bug() will produces a nasty warning and all of the function tracing features will be disabled until reboot. The simple solution is to treate module load the same way the core kernel is treated at boot. To hardcode the ftrace function modification of converting calls to mcount into nops. This is done in init/main.c there's no reason it could not be done in load_module(). This gives a better control of the changes and doesn't tie the state of the module to its notifiers as much. Ftrace is special, it needs to be treated as such. The reason this would work, is that the ftrace_module_init() would be called while the module is in MODULE_STATE_UNFORMED, which is ignored by the set_all_module_text_ro() call. Link: http://lkml.kernel.org/r/1395637826-3312-1-git-send-email-indou.takao@jp.fujitsu.com Reported-by: Takao Indoh <indou.takao@jp.fujitsu.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@vger.kernel.org # 2.6.38+ Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
861 lines
27 KiB
C
861 lines
27 KiB
C
/*
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* Ftrace header. For implementation details beyond the random comments
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* scattered below, see: Documentation/trace/ftrace-design.txt
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*/
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#ifndef _LINUX_FTRACE_H
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#define _LINUX_FTRACE_H
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#include <linux/trace_clock.h>
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#include <linux/kallsyms.h>
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#include <linux/linkage.h>
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#include <linux/bitops.h>
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#include <linux/ptrace.h>
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#include <linux/ktime.h>
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#include <linux/sched.h>
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#include <linux/types.h>
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#include <linux/init.h>
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#include <linux/fs.h>
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#include <asm/ftrace.h>
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/*
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* If the arch supports passing the variable contents of
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* function_trace_op as the third parameter back from the
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* mcount call, then the arch should define this as 1.
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*/
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#ifndef ARCH_SUPPORTS_FTRACE_OPS
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#define ARCH_SUPPORTS_FTRACE_OPS 0
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#endif
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/*
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* If the arch's mcount caller does not support all of ftrace's
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* features, then it must call an indirect function that
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* does. Or at least does enough to prevent any unwelcomed side effects.
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*/
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#if !defined(CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST) || \
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!ARCH_SUPPORTS_FTRACE_OPS
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# define FTRACE_FORCE_LIST_FUNC 1
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#else
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# define FTRACE_FORCE_LIST_FUNC 0
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#endif
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struct module;
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struct ftrace_hash;
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#ifdef CONFIG_FUNCTION_TRACER
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extern int ftrace_enabled;
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extern int
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ftrace_enable_sysctl(struct ctl_table *table, int write,
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void __user *buffer, size_t *lenp,
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loff_t *ppos);
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struct ftrace_ops;
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typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
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struct ftrace_ops *op, struct pt_regs *regs);
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/*
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* FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are
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* set in the flags member.
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*
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* ENABLED - set/unset when ftrace_ops is registered/unregistered
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* GLOBAL - set manualy by ftrace_ops user to denote the ftrace_ops
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* is part of the global tracers sharing the same filter
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* via set_ftrace_* debugfs files.
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* DYNAMIC - set when ftrace_ops is registered to denote dynamically
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* allocated ftrace_ops which need special care
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* CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops
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* could be controled by following calls:
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* ftrace_function_local_enable
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* ftrace_function_local_disable
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* SAVE_REGS - The ftrace_ops wants regs saved at each function called
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* and passed to the callback. If this flag is set, but the
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* architecture does not support passing regs
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* (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the
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* ftrace_ops will fail to register, unless the next flag
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* is set.
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* SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the
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* handler can handle an arch that does not save regs
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* (the handler tests if regs == NULL), then it can set
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* this flag instead. It will not fail registering the ftrace_ops
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* but, the regs field will be NULL if the arch does not support
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* passing regs to the handler.
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* Note, if this flag is set, the SAVE_REGS flag will automatically
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* get set upon registering the ftrace_ops, if the arch supports it.
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* RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure
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* that the call back has its own recursion protection. If it does
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* not set this, then the ftrace infrastructure will add recursion
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* protection for the caller.
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* STUB - The ftrace_ops is just a place holder.
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* INITIALIZED - The ftrace_ops has already been initialized (first use time
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* register_ftrace_function() is called, it will initialized the ops)
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* DELETED - The ops are being deleted, do not let them be registered again.
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*/
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enum {
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FTRACE_OPS_FL_ENABLED = 1 << 0,
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FTRACE_OPS_FL_GLOBAL = 1 << 1,
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FTRACE_OPS_FL_DYNAMIC = 1 << 2,
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FTRACE_OPS_FL_CONTROL = 1 << 3,
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FTRACE_OPS_FL_SAVE_REGS = 1 << 4,
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FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 5,
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FTRACE_OPS_FL_RECURSION_SAFE = 1 << 6,
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FTRACE_OPS_FL_STUB = 1 << 7,
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FTRACE_OPS_FL_INITIALIZED = 1 << 8,
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FTRACE_OPS_FL_DELETED = 1 << 9,
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};
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/*
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* Note, ftrace_ops can be referenced outside of RCU protection.
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* (Although, for perf, the control ops prevent that). If ftrace_ops is
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* allocated and not part of kernel core data, the unregistering of it will
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* perform a scheduling on all CPUs to make sure that there are no more users.
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* Depending on the load of the system that may take a bit of time.
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*
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* Any private data added must also take care not to be freed and if private
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* data is added to a ftrace_ops that is in core code, the user of the
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* ftrace_ops must perform a schedule_on_each_cpu() before freeing it.
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*/
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struct ftrace_ops {
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ftrace_func_t func;
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struct ftrace_ops *next;
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unsigned long flags;
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int __percpu *disabled;
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void *private;
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#ifdef CONFIG_DYNAMIC_FTRACE
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struct ftrace_hash *notrace_hash;
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struct ftrace_hash *filter_hash;
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struct mutex regex_lock;
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#endif
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};
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extern int function_trace_stop;
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/*
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* Type of the current tracing.
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*/
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enum ftrace_tracing_type_t {
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FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */
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FTRACE_TYPE_RETURN, /* Hook the return of the function */
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};
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/* Current tracing type, default is FTRACE_TYPE_ENTER */
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extern enum ftrace_tracing_type_t ftrace_tracing_type;
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/**
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* ftrace_stop - stop function tracer.
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*
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* A quick way to stop the function tracer. Note this an on off switch,
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* it is not something that is recursive like preempt_disable.
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* This does not disable the calling of mcount, it only stops the
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* calling of functions from mcount.
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*/
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static inline void ftrace_stop(void)
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{
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function_trace_stop = 1;
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}
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/**
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* ftrace_start - start the function tracer.
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*
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* This function is the inverse of ftrace_stop. This does not enable
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* the function tracing if the function tracer is disabled. This only
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* sets the function tracer flag to continue calling the functions
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* from mcount.
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*/
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static inline void ftrace_start(void)
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{
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function_trace_stop = 0;
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}
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/*
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* The ftrace_ops must be a static and should also
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* be read_mostly. These functions do modify read_mostly variables
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* so use them sparely. Never free an ftrace_op or modify the
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* next pointer after it has been registered. Even after unregistering
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* it, the next pointer may still be used internally.
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*/
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int register_ftrace_function(struct ftrace_ops *ops);
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int unregister_ftrace_function(struct ftrace_ops *ops);
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void clear_ftrace_function(void);
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/**
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* ftrace_function_local_enable - enable controlled ftrace_ops on current cpu
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*
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* This function enables tracing on current cpu by decreasing
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* the per cpu control variable.
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* It must be called with preemption disabled and only on ftrace_ops
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* registered with FTRACE_OPS_FL_CONTROL. If called without preemption
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* disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
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*/
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static inline void ftrace_function_local_enable(struct ftrace_ops *ops)
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{
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if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
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return;
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(*this_cpu_ptr(ops->disabled))--;
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}
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/**
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* ftrace_function_local_disable - enable controlled ftrace_ops on current cpu
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*
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* This function enables tracing on current cpu by decreasing
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* the per cpu control variable.
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* It must be called with preemption disabled and only on ftrace_ops
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* registered with FTRACE_OPS_FL_CONTROL. If called without preemption
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* disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
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*/
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static inline void ftrace_function_local_disable(struct ftrace_ops *ops)
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{
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if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)))
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return;
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(*this_cpu_ptr(ops->disabled))++;
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}
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/**
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* ftrace_function_local_disabled - returns ftrace_ops disabled value
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* on current cpu
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*
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* This function returns value of ftrace_ops::disabled on current cpu.
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* It must be called with preemption disabled and only on ftrace_ops
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* registered with FTRACE_OPS_FL_CONTROL. If called without preemption
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* disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled.
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*/
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static inline int ftrace_function_local_disabled(struct ftrace_ops *ops)
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{
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WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL));
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return *this_cpu_ptr(ops->disabled);
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}
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extern void ftrace_stub(unsigned long a0, unsigned long a1,
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struct ftrace_ops *op, struct pt_regs *regs);
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#else /* !CONFIG_FUNCTION_TRACER */
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/*
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* (un)register_ftrace_function must be a macro since the ops parameter
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* must not be evaluated.
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*/
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#define register_ftrace_function(ops) ({ 0; })
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#define unregister_ftrace_function(ops) ({ 0; })
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static inline int ftrace_nr_registered_ops(void)
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{
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return 0;
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}
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static inline void clear_ftrace_function(void) { }
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static inline void ftrace_kill(void) { }
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static inline void ftrace_stop(void) { }
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static inline void ftrace_start(void) { }
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#endif /* CONFIG_FUNCTION_TRACER */
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#ifdef CONFIG_STACK_TRACER
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extern int stack_tracer_enabled;
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int
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stack_trace_sysctl(struct ctl_table *table, int write,
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void __user *buffer, size_t *lenp,
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loff_t *ppos);
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#endif
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struct ftrace_func_command {
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struct list_head list;
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char *name;
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int (*func)(struct ftrace_hash *hash,
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char *func, char *cmd,
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char *params, int enable);
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};
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#ifdef CONFIG_DYNAMIC_FTRACE
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int ftrace_arch_code_modify_prepare(void);
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int ftrace_arch_code_modify_post_process(void);
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void ftrace_bug(int err, unsigned long ip);
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struct seq_file;
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struct ftrace_probe_ops {
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void (*func)(unsigned long ip,
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unsigned long parent_ip,
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void **data);
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int (*init)(struct ftrace_probe_ops *ops,
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unsigned long ip, void **data);
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void (*free)(struct ftrace_probe_ops *ops,
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unsigned long ip, void **data);
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int (*print)(struct seq_file *m,
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unsigned long ip,
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struct ftrace_probe_ops *ops,
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void *data);
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};
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extern int
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register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
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void *data);
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extern void
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unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
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void *data);
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extern void
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unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
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extern void unregister_ftrace_function_probe_all(char *glob);
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extern int ftrace_text_reserved(const void *start, const void *end);
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extern int ftrace_nr_registered_ops(void);
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/*
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* The dyn_ftrace record's flags field is split into two parts.
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* the first part which is '0-FTRACE_REF_MAX' is a counter of
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* the number of callbacks that have registered the function that
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* the dyn_ftrace descriptor represents.
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*
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* The second part is a mask:
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* ENABLED - the function is being traced
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* REGS - the record wants the function to save regs
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* REGS_EN - the function is set up to save regs.
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*
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* When a new ftrace_ops is registered and wants a function to save
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* pt_regs, the rec->flag REGS is set. When the function has been
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* set up to save regs, the REG_EN flag is set. Once a function
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* starts saving regs it will do so until all ftrace_ops are removed
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* from tracing that function.
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*/
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enum {
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FTRACE_FL_ENABLED = (1UL << 29),
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FTRACE_FL_REGS = (1UL << 30),
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FTRACE_FL_REGS_EN = (1UL << 31)
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};
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#define FTRACE_FL_MASK (0x7UL << 29)
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#define FTRACE_REF_MAX ((1UL << 29) - 1)
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struct dyn_ftrace {
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unsigned long ip; /* address of mcount call-site */
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unsigned long flags;
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struct dyn_arch_ftrace arch;
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};
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int ftrace_force_update(void);
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int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
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int remove, int reset);
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int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
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int len, int reset);
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int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
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int len, int reset);
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void ftrace_set_global_filter(unsigned char *buf, int len, int reset);
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void ftrace_set_global_notrace(unsigned char *buf, int len, int reset);
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void ftrace_free_filter(struct ftrace_ops *ops);
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int register_ftrace_command(struct ftrace_func_command *cmd);
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int unregister_ftrace_command(struct ftrace_func_command *cmd);
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enum {
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FTRACE_UPDATE_CALLS = (1 << 0),
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FTRACE_DISABLE_CALLS = (1 << 1),
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FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
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FTRACE_START_FUNC_RET = (1 << 3),
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FTRACE_STOP_FUNC_RET = (1 << 4),
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};
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/*
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* The FTRACE_UPDATE_* enum is used to pass information back
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* from the ftrace_update_record() and ftrace_test_record()
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* functions. These are called by the code update routines
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* to find out what is to be done for a given function.
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*
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* IGNORE - The function is already what we want it to be
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* MAKE_CALL - Start tracing the function
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* MODIFY_CALL - Stop saving regs for the function
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* MODIFY_CALL_REGS - Start saving regs for the function
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* MAKE_NOP - Stop tracing the function
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*/
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enum {
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FTRACE_UPDATE_IGNORE,
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FTRACE_UPDATE_MAKE_CALL,
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FTRACE_UPDATE_MODIFY_CALL,
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FTRACE_UPDATE_MODIFY_CALL_REGS,
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FTRACE_UPDATE_MAKE_NOP,
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};
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enum {
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FTRACE_ITER_FILTER = (1 << 0),
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FTRACE_ITER_NOTRACE = (1 << 1),
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FTRACE_ITER_PRINTALL = (1 << 2),
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FTRACE_ITER_DO_HASH = (1 << 3),
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FTRACE_ITER_HASH = (1 << 4),
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FTRACE_ITER_ENABLED = (1 << 5),
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};
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void arch_ftrace_update_code(int command);
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struct ftrace_rec_iter;
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struct ftrace_rec_iter *ftrace_rec_iter_start(void);
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struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter);
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struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter);
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#define for_ftrace_rec_iter(iter) \
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for (iter = ftrace_rec_iter_start(); \
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iter; \
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iter = ftrace_rec_iter_next(iter))
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int ftrace_update_record(struct dyn_ftrace *rec, int enable);
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int ftrace_test_record(struct dyn_ftrace *rec, int enable);
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void ftrace_run_stop_machine(int command);
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unsigned long ftrace_location(unsigned long ip);
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extern ftrace_func_t ftrace_trace_function;
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int ftrace_regex_open(struct ftrace_ops *ops, int flag,
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struct inode *inode, struct file *file);
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ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
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size_t cnt, loff_t *ppos);
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ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
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size_t cnt, loff_t *ppos);
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int ftrace_regex_release(struct inode *inode, struct file *file);
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void __init
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ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable);
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/* defined in arch */
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extern int ftrace_ip_converted(unsigned long ip);
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extern int ftrace_dyn_arch_init(void);
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extern void ftrace_replace_code(int enable);
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extern int ftrace_update_ftrace_func(ftrace_func_t func);
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extern void ftrace_caller(void);
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extern void ftrace_regs_caller(void);
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extern void ftrace_call(void);
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extern void ftrace_regs_call(void);
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extern void mcount_call(void);
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void ftrace_modify_all_code(int command);
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#ifndef FTRACE_ADDR
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#define FTRACE_ADDR ((unsigned long)ftrace_caller)
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#endif
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#ifndef FTRACE_REGS_ADDR
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#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
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# define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller)
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#else
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# define FTRACE_REGS_ADDR FTRACE_ADDR
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#endif
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#endif
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER
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extern void ftrace_graph_caller(void);
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extern int ftrace_enable_ftrace_graph_caller(void);
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extern int ftrace_disable_ftrace_graph_caller(void);
|
|
#else
|
|
static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; }
|
|
static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; }
|
|
#endif
|
|
|
|
/**
|
|
* ftrace_make_nop - convert code into nop
|
|
* @mod: module structure if called by module load initialization
|
|
* @rec: the mcount call site record
|
|
* @addr: the address that the call site should be calling
|
|
*
|
|
* This is a very sensitive operation and great care needs
|
|
* to be taken by the arch. The operation should carefully
|
|
* read the location, check to see if what is read is indeed
|
|
* what we expect it to be, and then on success of the compare,
|
|
* it should write to the location.
|
|
*
|
|
* The code segment at @rec->ip should be a caller to @addr
|
|
*
|
|
* Return must be:
|
|
* 0 on success
|
|
* -EFAULT on error reading the location
|
|
* -EINVAL on a failed compare of the contents
|
|
* -EPERM on error writing to the location
|
|
* Any other value will be considered a failure.
|
|
*/
|
|
extern int ftrace_make_nop(struct module *mod,
|
|
struct dyn_ftrace *rec, unsigned long addr);
|
|
|
|
/**
|
|
* ftrace_make_call - convert a nop call site into a call to addr
|
|
* @rec: the mcount call site record
|
|
* @addr: the address that the call site should call
|
|
*
|
|
* This is a very sensitive operation and great care needs
|
|
* to be taken by the arch. The operation should carefully
|
|
* read the location, check to see if what is read is indeed
|
|
* what we expect it to be, and then on success of the compare,
|
|
* it should write to the location.
|
|
*
|
|
* The code segment at @rec->ip should be a nop
|
|
*
|
|
* Return must be:
|
|
* 0 on success
|
|
* -EFAULT on error reading the location
|
|
* -EINVAL on a failed compare of the contents
|
|
* -EPERM on error writing to the location
|
|
* Any other value will be considered a failure.
|
|
*/
|
|
extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr);
|
|
|
|
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
|
|
/**
|
|
* ftrace_modify_call - convert from one addr to another (no nop)
|
|
* @rec: the mcount call site record
|
|
* @old_addr: the address expected to be currently called to
|
|
* @addr: the address to change to
|
|
*
|
|
* This is a very sensitive operation and great care needs
|
|
* to be taken by the arch. The operation should carefully
|
|
* read the location, check to see if what is read is indeed
|
|
* what we expect it to be, and then on success of the compare,
|
|
* it should write to the location.
|
|
*
|
|
* The code segment at @rec->ip should be a caller to @old_addr
|
|
*
|
|
* Return must be:
|
|
* 0 on success
|
|
* -EFAULT on error reading the location
|
|
* -EINVAL on a failed compare of the contents
|
|
* -EPERM on error writing to the location
|
|
* Any other value will be considered a failure.
|
|
*/
|
|
extern int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
|
|
unsigned long addr);
|
|
#else
|
|
/* Should never be called */
|
|
static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
|
|
unsigned long addr)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
#endif
|
|
|
|
/* May be defined in arch */
|
|
extern int ftrace_arch_read_dyn_info(char *buf, int size);
|
|
|
|
extern int skip_trace(unsigned long ip);
|
|
extern void ftrace_module_init(struct module *mod);
|
|
|
|
extern void ftrace_disable_daemon(void);
|
|
extern void ftrace_enable_daemon(void);
|
|
#else /* CONFIG_DYNAMIC_FTRACE */
|
|
static inline int skip_trace(unsigned long ip) { return 0; }
|
|
static inline int ftrace_force_update(void) { return 0; }
|
|
static inline void ftrace_disable_daemon(void) { }
|
|
static inline void ftrace_enable_daemon(void) { }
|
|
static inline void ftrace_release_mod(struct module *mod) {}
|
|
static inline void ftrace_module_init(struct module *mod) {}
|
|
static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
static inline __init int unregister_ftrace_command(char *cmd_name)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
static inline int ftrace_text_reserved(const void *start, const void *end)
|
|
{
|
|
return 0;
|
|
}
|
|
static inline unsigned long ftrace_location(unsigned long ip)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Again users of functions that have ftrace_ops may not
|
|
* have them defined when ftrace is not enabled, but these
|
|
* functions may still be called. Use a macro instead of inline.
|
|
*/
|
|
#define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; })
|
|
#define ftrace_set_early_filter(ops, buf, enable) do { } while (0)
|
|
#define ftrace_set_filter_ip(ops, ip, remove, reset) ({ -ENODEV; })
|
|
#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)
|
|
|
|
static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf,
|
|
size_t cnt, loff_t *ppos) { return -ENODEV; }
|
|
static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf,
|
|
size_t cnt, loff_t *ppos) { return -ENODEV; }
|
|
static inline int
|
|
ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; }
|
|
#endif /* CONFIG_DYNAMIC_FTRACE */
|
|
|
|
/* totally disable ftrace - can not re-enable after this */
|
|
void ftrace_kill(void);
|
|
|
|
static inline void tracer_disable(void)
|
|
{
|
|
#ifdef CONFIG_FUNCTION_TRACER
|
|
ftrace_enabled = 0;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Ftrace disable/restore without lock. Some synchronization mechanism
|
|
* must be used to prevent ftrace_enabled to be changed between
|
|
* disable/restore.
|
|
*/
|
|
static inline int __ftrace_enabled_save(void)
|
|
{
|
|
#ifdef CONFIG_FUNCTION_TRACER
|
|
int saved_ftrace_enabled = ftrace_enabled;
|
|
ftrace_enabled = 0;
|
|
return saved_ftrace_enabled;
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
static inline void __ftrace_enabled_restore(int enabled)
|
|
{
|
|
#ifdef CONFIG_FUNCTION_TRACER
|
|
ftrace_enabled = enabled;
|
|
#endif
|
|
}
|
|
|
|
#ifndef HAVE_ARCH_CALLER_ADDR
|
|
# ifdef CONFIG_FRAME_POINTER
|
|
# define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
|
|
# define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
|
|
# define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
|
|
# define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
|
|
# define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
|
|
# define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
|
|
# define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
|
|
# else
|
|
# define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
|
|
# define CALLER_ADDR1 0UL
|
|
# define CALLER_ADDR2 0UL
|
|
# define CALLER_ADDR3 0UL
|
|
# define CALLER_ADDR4 0UL
|
|
# define CALLER_ADDR5 0UL
|
|
# define CALLER_ADDR6 0UL
|
|
# endif
|
|
#endif /* ifndef HAVE_ARCH_CALLER_ADDR */
|
|
|
|
#ifdef CONFIG_IRQSOFF_TRACER
|
|
extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
|
|
extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
|
|
#else
|
|
static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { }
|
|
static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { }
|
|
#endif
|
|
|
|
#ifdef CONFIG_PREEMPT_TRACER
|
|
extern void trace_preempt_on(unsigned long a0, unsigned long a1);
|
|
extern void trace_preempt_off(unsigned long a0, unsigned long a1);
|
|
#else
|
|
/*
|
|
* Use defines instead of static inlines because some arches will make code out
|
|
* of the CALLER_ADDR, when we really want these to be a real nop.
|
|
*/
|
|
# define trace_preempt_on(a0, a1) do { } while (0)
|
|
# define trace_preempt_off(a0, a1) do { } while (0)
|
|
#endif
|
|
|
|
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
|
|
extern void ftrace_init(void);
|
|
#else
|
|
static inline void ftrace_init(void) { }
|
|
#endif
|
|
|
|
/*
|
|
* Structure that defines an entry function trace.
|
|
*/
|
|
struct ftrace_graph_ent {
|
|
unsigned long func; /* Current function */
|
|
int depth;
|
|
};
|
|
|
|
/*
|
|
* Structure that defines a return function trace.
|
|
*/
|
|
struct ftrace_graph_ret {
|
|
unsigned long func; /* Current function */
|
|
unsigned long long calltime;
|
|
unsigned long long rettime;
|
|
/* Number of functions that overran the depth limit for current task */
|
|
unsigned long overrun;
|
|
int depth;
|
|
};
|
|
|
|
/* Type of the callback handlers for tracing function graph*/
|
|
typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */
|
|
typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */
|
|
|
|
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
|
|
/* for init task */
|
|
#define INIT_FTRACE_GRAPH .ret_stack = NULL,
|
|
|
|
/*
|
|
* Stack of return addresses for functions
|
|
* of a thread.
|
|
* Used in struct thread_info
|
|
*/
|
|
struct ftrace_ret_stack {
|
|
unsigned long ret;
|
|
unsigned long func;
|
|
unsigned long long calltime;
|
|
unsigned long long subtime;
|
|
unsigned long fp;
|
|
};
|
|
|
|
/*
|
|
* Primary handler of a function return.
|
|
* It relays on ftrace_return_to_handler.
|
|
* Defined in entry_32/64.S
|
|
*/
|
|
extern void return_to_handler(void);
|
|
|
|
extern int
|
|
ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
|
|
unsigned long frame_pointer);
|
|
|
|
/*
|
|
* Sometimes we don't want to trace a function with the function
|
|
* graph tracer but we want them to keep traced by the usual function
|
|
* tracer if the function graph tracer is not configured.
|
|
*/
|
|
#define __notrace_funcgraph notrace
|
|
|
|
/*
|
|
* We want to which function is an entrypoint of a hardirq.
|
|
* That will help us to put a signal on output.
|
|
*/
|
|
#define __irq_entry __attribute__((__section__(".irqentry.text")))
|
|
|
|
/* Limits of hardirq entrypoints */
|
|
extern char __irqentry_text_start[];
|
|
extern char __irqentry_text_end[];
|
|
|
|
#define FTRACE_NOTRACE_DEPTH 65536
|
|
#define FTRACE_RETFUNC_DEPTH 50
|
|
#define FTRACE_RETSTACK_ALLOC_SIZE 32
|
|
extern int register_ftrace_graph(trace_func_graph_ret_t retfunc,
|
|
trace_func_graph_ent_t entryfunc);
|
|
|
|
extern void ftrace_graph_stop(void);
|
|
|
|
/* The current handlers in use */
|
|
extern trace_func_graph_ret_t ftrace_graph_return;
|
|
extern trace_func_graph_ent_t ftrace_graph_entry;
|
|
|
|
extern void unregister_ftrace_graph(void);
|
|
|
|
extern void ftrace_graph_init_task(struct task_struct *t);
|
|
extern void ftrace_graph_exit_task(struct task_struct *t);
|
|
extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu);
|
|
|
|
static inline int task_curr_ret_stack(struct task_struct *t)
|
|
{
|
|
return t->curr_ret_stack;
|
|
}
|
|
|
|
static inline void pause_graph_tracing(void)
|
|
{
|
|
atomic_inc(¤t->tracing_graph_pause);
|
|
}
|
|
|
|
static inline void unpause_graph_tracing(void)
|
|
{
|
|
atomic_dec(¤t->tracing_graph_pause);
|
|
}
|
|
#else /* !CONFIG_FUNCTION_GRAPH_TRACER */
|
|
|
|
#define __notrace_funcgraph
|
|
#define __irq_entry
|
|
#define INIT_FTRACE_GRAPH
|
|
|
|
static inline void ftrace_graph_init_task(struct task_struct *t) { }
|
|
static inline void ftrace_graph_exit_task(struct task_struct *t) { }
|
|
static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { }
|
|
|
|
static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc,
|
|
trace_func_graph_ent_t entryfunc)
|
|
{
|
|
return -1;
|
|
}
|
|
static inline void unregister_ftrace_graph(void) { }
|
|
|
|
static inline int task_curr_ret_stack(struct task_struct *tsk)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
static inline void pause_graph_tracing(void) { }
|
|
static inline void unpause_graph_tracing(void) { }
|
|
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
|
|
|
|
#ifdef CONFIG_TRACING
|
|
|
|
/* flags for current->trace */
|
|
enum {
|
|
TSK_TRACE_FL_TRACE_BIT = 0,
|
|
TSK_TRACE_FL_GRAPH_BIT = 1,
|
|
};
|
|
enum {
|
|
TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT,
|
|
TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT,
|
|
};
|
|
|
|
static inline void set_tsk_trace_trace(struct task_struct *tsk)
|
|
{
|
|
set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
|
|
}
|
|
|
|
static inline void clear_tsk_trace_trace(struct task_struct *tsk)
|
|
{
|
|
clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace);
|
|
}
|
|
|
|
static inline int test_tsk_trace_trace(struct task_struct *tsk)
|
|
{
|
|
return tsk->trace & TSK_TRACE_FL_TRACE;
|
|
}
|
|
|
|
static inline void set_tsk_trace_graph(struct task_struct *tsk)
|
|
{
|
|
set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
|
|
}
|
|
|
|
static inline void clear_tsk_trace_graph(struct task_struct *tsk)
|
|
{
|
|
clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace);
|
|
}
|
|
|
|
static inline int test_tsk_trace_graph(struct task_struct *tsk)
|
|
{
|
|
return tsk->trace & TSK_TRACE_FL_GRAPH;
|
|
}
|
|
|
|
enum ftrace_dump_mode;
|
|
|
|
extern enum ftrace_dump_mode ftrace_dump_on_oops;
|
|
|
|
extern void disable_trace_on_warning(void);
|
|
extern int __disable_trace_on_warning;
|
|
|
|
#ifdef CONFIG_PREEMPT
|
|
#define INIT_TRACE_RECURSION .trace_recursion = 0,
|
|
#endif
|
|
|
|
#else /* CONFIG_TRACING */
|
|
static inline void disable_trace_on_warning(void) { }
|
|
#endif /* CONFIG_TRACING */
|
|
|
|
#ifndef INIT_TRACE_RECURSION
|
|
#define INIT_TRACE_RECURSION
|
|
#endif
|
|
|
|
#ifdef CONFIG_FTRACE_SYSCALLS
|
|
|
|
unsigned long arch_syscall_addr(int nr);
|
|
|
|
#endif /* CONFIG_FTRACE_SYSCALLS */
|
|
|
|
#endif /* _LINUX_FTRACE_H */
|