/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_KERNEL_TRACE_H#define _LINUX_KERNEL_TRACE_H #include <linux/fs.h>#include <linux/atomic.h>#include <linux/sched.h>#include <linux/clocksource.h>#include <linux/ring_buffer.h>#include <linux/mmiotrace.h>#include <linux/tracepoint.h>#include <linux/ftrace.h>#include <linux/hw_breakpoint.h>#include <linux/trace_seq.h>#include <linux/trace_events.h>#include <linux/compiler.h>#include <linux/trace_seq.h>#include <linux/glob.h> #ifdef CONFIG_FTRACE_SYSCALLS#include <asm/unistd.h> /* For NR_SYSCALLS */#include <asm/syscall.h> /* some archs define it here */#endif enum trace_type { __TRACE_FIRST_TYPE = 0, TRACE_FN, TRACE_CTX, TRACE_WAKE, TRACE_STACK, TRACE_PRINT, TRACE_BPRINT, TRACE_MMIO_RW, TRACE_MMIO_MAP, TRACE_BRANCH, TRACE_GRAPH_RET, TRACE_GRAPH_ENT, TRACE_USER_STACK, TRACE_BLK, TRACE_BPUTS, TRACE_HWLAT, TRACE_RAW_DATA, __TRACE_LAST_TYPE,}; #undef __field#define __field(type, item) type item; #undef __field_struct#define __field_struct(type, item) __field(type, item) #undef __field_desc#define __field_desc(type, container, item) #undef __array#define __array(type, item, size) type item[size]; #undef __array_desc#define __array_desc(type, container, item, size) #undef __dynamic_array#define __dynamic_array(type, item) type item[]; #undef F_STRUCT#define F_STRUCT(args...) args #undef FTRACE_ENTRY#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ struct struct_name { \ struct trace_entry ent; \ tstruct \ } #undef FTRACE_ENTRY_DUP#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) #undef FTRACE_ENTRY_REG#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ filter, regfn) \ FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) #undef FTRACE_ENTRY_PACKED#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \ filter) \ FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) __packed #include "trace_entries.h" /* * syscalls are special, and need special handling, this is why * they are not included in trace_entries.h */struct syscall_trace_enter { struct trace_entry ent; int nr; unsigned long args[];}; struct syscall_trace_exit { struct trace_entry ent; int nr; long ret;}; struct kprobe_trace_entry_head { struct trace_entry ent; unsigned long ip;}; struct kretprobe_trace_entry_head { struct trace_entry ent; unsigned long func; unsigned long ret_ip;}; /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: * IRQS_OFF - interrupts were disabled * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags * NEED_RESCHED - reschedule is requested * HARDIRQ - inside an interrupt handler * SOFTIRQ - inside a softirq handler */enum trace_flag_type { TRACE_FLAG_IRQS_OFF = 0x01, TRACE_FLAG_IRQS_NOSUPPORT = 0x02, TRACE_FLAG_NEED_RESCHED = 0x04, TRACE_FLAG_HARDIRQ = 0x08, TRACE_FLAG_SOFTIRQ = 0x10, TRACE_FLAG_PREEMPT_RESCHED = 0x20, TRACE_FLAG_NMI = 0x40,}; #define TRACE_BUF_SIZE 1024 struct trace_array; /* * The CPU trace array - it consists of thousands of trace entries * plus some other descriptor data: (for example which task started * the trace, etc.) */struct trace_array_cpu { atomic_t disabled; void *buffer_page; /* ring buffer spare */ unsigned long entries; unsigned long saved_latency; unsigned long critical_start; unsigned long critical_end; unsigned long critical_sequence; unsigned long nice; unsigned long policy; unsigned long rt_priority; unsigned long skipped_entries; u64 preempt_timestamp; pid_t pid; kuid_t uid; char comm[TASK_COMM_LEN]; bool ignore_pid;#ifdef CONFIG_FUNCTION_TRACER bool ftrace_ignore_pid;#endif}; struct tracer;struct trace_option_dentry; struct trace_buffer { struct trace_array *tr; struct ring_buffer *buffer; struct trace_array_cpu __percpu *data; u64 time_start; int cpu;}; #define TRACE_FLAGS_MAX_SIZE 32 struct trace_options { struct tracer *tracer; struct trace_option_dentry *topts;}; struct trace_pid_list { int pid_max; unsigned long *pids;}; /* * The trace array - an array of per-CPU trace arrays. This is the * highest level data structure that individual tracers deal with. * They have on/off state as well: */struct trace_array { struct list_head list; char *name; struct trace_buffer trace_buffer;#ifdef CONFIG_TRACER_MAX_TRACE /* * The max_buffer is used to snapshot the trace when a maximum * latency is reached, or when the user initiates a snapshot. * Some tracers will use this to store a maximum trace while * it continues examining live traces. * * The buffers for the max_buffer are set up the same as the trace_buffer * When a snapshot is taken, the buffer of the max_buffer is swapped * with the buffer of the trace_buffer and the buffers are reset for * the trace_buffer so the tracing can continue. */ struct trace_buffer max_buffer; bool allocated_snapshot;#endif#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) unsigned long max_latency;#endif struct trace_pid_list __rcu *filtered_pids; /* * max_lock is used to protect the swapping of buffers * when taking a max snapshot. The buffers themselves are * protected by per_cpu spinlocks. But the action of the swap * needs its own lock. * * This is defined as a arch_spinlock_t in order to help * with performance when lockdep debugging is enabled. * * It is also used in other places outside the update_max_tr * so it needs to be defined outside of the * CONFIG_TRACER_MAX_TRACE. */ arch_spinlock_t max_lock; int buffer_disabled;#ifdef CONFIG_FTRACE_SYSCALLS int sys_refcount_enter; int sys_refcount_exit; struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];#endif int stop_count; int clock_id; int nr_topts; bool clear_trace; struct tracer *current_trace; unsigned int trace_flags; unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; unsigned int flags; raw_spinlock_t start_lock; struct dentry *dir; struct dentry *options; struct dentry *percpu_dir; struct dentry *event_dir; struct trace_options *topts; struct list_head systems; struct list_head events; cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ int ref;#ifdef CONFIG_FUNCTION_TRACER struct ftrace_ops *ops; struct trace_pid_list __rcu *function_pids;#ifdef CONFIG_DYNAMIC_FTRACE /* All of these are protected by the ftrace_lock */ struct list_head func_probes; struct list_head mod_trace; struct list_head mod_notrace;#endif /* function tracing enabled */ int function_enabled;#endif}; enum { TRACE_ARRAY_FL_GLOBAL = (1 << 0)}; extern struct list_head ftrace_trace_arrays; extern struct mutex trace_types_lock; extern int trace_array_get(struct trace_array *tr);extern void trace_array_put(struct trace_array *tr); /* * The global tracer (top) should be the first trace array added, * but we check the flag anyway. */static inline struct trace_array *top_trace_array(void){ struct trace_array *tr; if (list_empty(&ftrace_trace_arrays)) return NULL; tr = list_entry(ftrace_trace_arrays.prev, typeof(*tr), list); WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); return tr;} #define FTRACE_CMP_TYPE(var, type) \ __builtin_types_compatible_p(typeof(var), type *) #undef IF_ASSIGN#define IF_ASSIGN(var, entry, etype, id) \ if (FTRACE_CMP_TYPE(var, etype)) { \ var = (typeof(var))(entry); \ WARN_ON(id && (entry)->type != id); \ break; \ } /* Will cause compile errors if type is not found. */extern void __ftrace_bad_type(void); /* * The trace_assign_type is a verifier that the entry type is * the same as the type being assigned. To add new types simply * add a line with the following format: * * IF_ASSIGN(var, ent, type, id); * * Where "type" is the trace type that includes the trace_entry * as the "ent" item. And "id" is the trace identifier that is * used in the trace_type enum. * * If the type can have more than one id, then use zero. */#define trace_assign_type(var, ent) \ do { \ IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ TRACE_MMIO_RW); \ IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ TRACE_MMIO_MAP); \ IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ TRACE_GRAPH_ENT); \ IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ TRACE_GRAPH_RET); \ __ftrace_bad_type(); \ } while (0) /* * An option specific to a tracer. This is a boolean value. * The bit is the bit index that sets its value on the * flags value in struct tracer_flags. */struct tracer_opt { const char *name; /* Will appear on the trace_options file */ u32 bit; /* Mask assigned in val field in tracer_flags */}; /* * The set of specific options for a tracer. Your tracer * have to set the initial value of the flags val. */struct tracer_flags { u32 val; struct tracer_opt *opts; struct tracer *trace;}; /* Makes more easy to define a tracer opt */#define TRACER_OPT(s, b) .name = #s, .bit = b struct trace_option_dentry { struct tracer_opt *opt; struct tracer_flags *flags; struct trace_array *tr; struct dentry *entry;}; /** * struct tracer - a specific tracer and its callbacks to interact with tracefs * @name: the name chosen to select it on the available_tracers file * @init: called when one switches to this tracer (echo name > current_tracer) * @reset: called when one switches to another tracer * @start: called when tracing is unpaused (echo 1 > tracing_on) * @stop: called when tracing is paused (echo 0 > tracing_on) * @update_thresh: called when tracing_thresh is updated * @open: called when the trace file is opened * @pipe_open: called when the trace_pipe file is opened * @close: called when the trace file is released * @pipe_close: called when the trace_pipe file is released * @read: override the default read callback on trace_pipe * @splice_read: override the default splice_read callback on trace_pipe * @selftest: selftest to run on boot (see trace_selftest.c) * @print_headers: override the first lines that describe your columns * @print_line: callback that prints a trace * @set_flag: signals one of your private flags changed (trace_options file) * @flags: your private flags */struct tracer { const char *name; int (*init)(struct trace_array *tr); void (*reset)(struct trace_array *tr); void (*start)(struct trace_array *tr); void (*stop)(struct trace_array *tr); int (*update_thresh)(struct trace_array *tr); void (*open)(struct trace_iterator *iter); void (*pipe_open)(struct trace_iterator *iter); void (*close)(struct trace_iterator *iter); void (*pipe_close)(struct trace_iterator *iter); ssize_t (*read)(struct trace_iterator *iter, struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos); ssize_t (*splice_read)(struct trace_iterator *iter, struct file *filp, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags);#ifdef CONFIG_FTRACE_STARTUP_TEST int (*selftest)(struct tracer *trace, struct trace_array *tr);#endif void (*print_header)(struct seq_file *m); enum print_line_t (*print_line)(struct trace_iterator *iter); /* If you handled the flag setting, return 0 */ int (*set_flag)(struct trace_array *tr, u32 old_flags, u32 bit, int set); /* Return 0 if OK with change, else return non-zero */ int (*flag_changed)(struct trace_array *tr, u32 mask, int set); struct tracer *next; struct tracer_flags *flags; int enabled; int ref; bool print_max; bool allow_instances;#ifdef CONFIG_TRACER_MAX_TRACE bool use_max_tr;#endif /* True if tracer cannot be enabled in kernel param */ bool noboot;}; /* Only current can touch trace_recursion */ /* * For function tracing recursion: * The order of these bits are important. * * When function tracing occurs, the following steps are made: * If arch does not support a ftrace feature: * call internal function (uses INTERNAL bits) which calls... * If callback is registered to the "global" list, the list * function is called and recursion checks the GLOBAL bits. * then this function calls... * The function callback, which can use the FTRACE bits to * check for recursion. * * Now if the arch does not suppport a feature, and it calls * the global list function which calls the ftrace callback * all three of these steps will do a recursion protection. * There's no reason to do one if the previous caller already * did. The recursion that we are protecting against will * go through the same steps again. * * To prevent the multiple recursion checks, if a recursion * bit is set that is higher than the MAX bit of the current * check, then we know that the check was made by the previous * caller, and we can skip the current check. */enum { TRACE_BUFFER_BIT, TRACE_BUFFER_NMI_BIT, TRACE_BUFFER_IRQ_BIT, TRACE_BUFFER_SIRQ_BIT, /* Start of function recursion bits */ TRACE_FTRACE_BIT, TRACE_FTRACE_NMI_BIT, TRACE_FTRACE_IRQ_BIT, TRACE_FTRACE_SIRQ_BIT, /* INTERNAL_BITs must be greater than FTRACE_BITs */ TRACE_INTERNAL_BIT, TRACE_INTERNAL_NMI_BIT, TRACE_INTERNAL_IRQ_BIT, TRACE_INTERNAL_SIRQ_BIT, TRACE_BRANCH_BIT,/* * Abuse of the trace_recursion.Lines 1–500 of 1812. Load more
/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_KERNEL_TRACE_H #define _LINUX_KERNEL_TRACE_H #include <linux/fs.h> #include <linux/atomic.h> #include <linux/sched.h> #include <linux/clocksource.h> #include <linux/ring_buffer.h> #include <linux/mmiotrace.h> #include <linux/tracepoint.h> #include <linux/ftrace.h> #include <linux/hw_breakpoint.h> #include <linux/trace_seq.h> #include <linux/trace_events.h> #include <linux/compiler.h> #include <linux/trace_seq.h> #include <linux/glob.h> #ifdef CONFIG_FTRACE_SYSCALLS #include <asm/unistd.h> /* For NR_SYSCALLS */ #include <asm/syscall.h> /* some archs define it here */ #endif enum trace_type { __TRACE_FIRST_TYPE = 0, TRACE_FN, TRACE_CTX, TRACE_WAKE, TRACE_STACK, TRACE_PRINT, TRACE_BPRINT, TRACE_MMIO_RW, TRACE_MMIO_MAP, TRACE_BRANCH, TRACE_GRAPH_RET, TRACE_GRAPH_ENT, TRACE_USER_STACK, TRACE_BLK, TRACE_BPUTS, TRACE_HWLAT, TRACE_RAW_DATA, __TRACE_LAST_TYPE, }; #undef __field #define __field(type, item) type item; #undef __field_struct #define __field_struct(type, item) __field(type, item) #undef __field_desc #define __field_desc(type, container, item) #undef __array #define __array(type, item, size) type item[size]; #undef __array_desc #define __array_desc(type, container, item, size) #undef __dynamic_array #define __dynamic_array(type, item) type item[]; #undef F_STRUCT #define F_STRUCT(args...) args #undef FTRACE_ENTRY #define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \ struct struct_name { \ struct trace_entry ent; \ tstruct \ } #undef FTRACE_ENTRY_DUP #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) #undef FTRACE_ENTRY_REG #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \ filter, regfn) \ FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) #undef FTRACE_ENTRY_PACKED #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \ filter) \ FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \ filter) __packed #include "trace_entries.h" /* * syscalls are special, and need special handling, this is why * they are not included in trace_entries.h */ struct syscall_trace_enter { struct trace_entry ent; int nr; unsigned long args[]; }; struct syscall_trace_exit { struct trace_entry ent; int nr; long ret; }; struct kprobe_trace_entry_head { struct trace_entry ent; unsigned long ip; }; struct kretprobe_trace_entry_head { struct trace_entry ent; unsigned long func; unsigned long ret_ip; }; /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: * IRQS_OFF - interrupts were disabled * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags * NEED_RESCHED - reschedule is requested * HARDIRQ - inside an interrupt handler * SOFTIRQ - inside a softirq handler */ enum trace_flag_type { TRACE_FLAG_IRQS_OFF = 0x01, TRACE_FLAG_IRQS_NOSUPPORT = 0x02, TRACE_FLAG_NEED_RESCHED = 0x04, TRACE_FLAG_HARDIRQ = 0x08, TRACE_FLAG_SOFTIRQ = 0x10, TRACE_FLAG_PREEMPT_RESCHED = 0x20, TRACE_FLAG_NMI = 0x40, }; #define TRACE_BUF_SIZE 1024 struct trace_array; /* * The CPU trace array - it consists of thousands of trace entries * plus some other descriptor data: (for example which task started * the trace, etc.) */ struct trace_array_cpu { atomic_t disabled; void *buffer_page; /* ring buffer spare */ unsigned long entries; unsigned long saved_latency; unsigned long critical_start; unsigned long critical_end; unsigned long critical_sequence; unsigned long nice; unsigned long policy; unsigned long rt_priority; unsigned long skipped_entries; u64 preempt_timestamp; pid_t pid; kuid_t uid; char comm[TASK_COMM_LEN]; bool ignore_pid; #ifdef CONFIG_FUNCTION_TRACER bool ftrace_ignore_pid; #endif }; struct tracer; struct trace_option_dentry; struct trace_buffer { struct trace_array *tr; struct ring_buffer *buffer; struct trace_array_cpu __percpu *data; u64 time_start; int cpu; }; #define TRACE_FLAGS_MAX_SIZE 32 struct trace_options { struct tracer *tracer; struct trace_option_dentry *topts; }; struct trace_pid_list { int pid_max; unsigned long *pids; }; /* * The trace array - an array of per-CPU trace arrays. This is the * highest level data structure that individual tracers deal with. * They have on/off state as well: */ struct trace_array { struct list_head list; char *name; struct trace_buffer trace_buffer; #ifdef CONFIG_TRACER_MAX_TRACE /* * The max_buffer is used to snapshot the trace when a maximum * latency is reached, or when the user initiates a snapshot. * Some tracers will use this to store a maximum trace while * it continues examining live traces. * * The buffers for the max_buffer are set up the same as the trace_buffer * When a snapshot is taken, the buffer of the max_buffer is swapped * with the buffer of the trace_buffer and the buffers are reset for * the trace_buffer so the tracing can continue. */ struct trace_buffer max_buffer; bool allocated_snapshot; #endif #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) unsigned long max_latency; #endif struct trace_pid_list __rcu *filtered_pids; /* * max_lock is used to protect the swapping of buffers * when taking a max snapshot. The buffers themselves are * protected by per_cpu spinlocks. But the action of the swap * needs its own lock. * * This is defined as a arch_spinlock_t in order to help * with performance when lockdep debugging is enabled. * * It is also used in other places outside the update_max_tr * so it needs to be defined outside of the * CONFIG_TRACER_MAX_TRACE. */ arch_spinlock_t max_lock; int buffer_disabled; #ifdef CONFIG_FTRACE_SYSCALLS int sys_refcount_enter; int sys_refcount_exit; struct trace_event_file __rcu *enter_syscall_files[NR_syscalls]; struct trace_event_file __rcu *exit_syscall_files[NR_syscalls]; #endif int stop_count; int clock_id; int nr_topts; bool clear_trace; struct tracer *current_trace; unsigned int trace_flags; unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; unsigned int flags; raw_spinlock_t start_lock; struct dentry *dir; struct dentry *options; struct dentry *percpu_dir; struct dentry *event_dir; struct trace_options *topts; struct list_head systems; struct list_head events; cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ int ref; #ifdef CONFIG_FUNCTION_TRACER struct ftrace_ops *ops; struct trace_pid_list __rcu *function_pids; #ifdef CONFIG_DYNAMIC_FTRACE /* All of these are protected by the ftrace_lock */ struct list_head func_probes; struct list_head mod_trace; struct list_head mod_notrace; #endif /* function tracing enabled */ int function_enabled; #endif }; enum { TRACE_ARRAY_FL_GLOBAL = (1 << 0) }; extern struct list_head ftrace_trace_arrays; extern struct mutex trace_types_lock; extern int trace_array_get(struct trace_array *tr); extern void trace_array_put(struct trace_array *tr); /* * The global tracer (top) should be the first trace array added, * but we check the flag anyway. */ static inline struct trace_array *top_trace_array(void) { struct trace_array *tr; if (list_empty(&ftrace_trace_arrays)) return NULL; tr = list_entry(ftrace_trace_arrays.prev, typeof(*tr), list); WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL)); return tr; } #define FTRACE_CMP_TYPE(var, type) \ __builtin_types_compatible_p(typeof(var), type *) #undef IF_ASSIGN #define IF_ASSIGN(var, entry, etype, id) \ if (FTRACE_CMP_TYPE(var, etype)) { \ var = (typeof(var))(entry); \ WARN_ON(id && (entry)->type != id); \ break; \ } /* Will cause compile errors if type is not found. */ extern void __ftrace_bad_type(void); /* * The trace_assign_type is a verifier that the entry type is * the same as the type being assigned. To add new types simply * add a line with the following format: * * IF_ASSIGN(var, ent, type, id); * * Where "type" is the trace type that includes the trace_entry * as the "ent" item. And "id" is the trace identifier that is * used in the trace_type enum. * * If the type can have more than one id, then use zero. */ #define trace_assign_type(var, ent) \ do { \ IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \ IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \ IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \ IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\ IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \ IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \ IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \ IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \ IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\ IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \ TRACE_MMIO_RW); \ IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \ TRACE_MMIO_MAP); \ IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \ IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \ TRACE_GRAPH_ENT); \ IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \ TRACE_GRAPH_RET); \ __ftrace_bad_type(); \ } while (0) /* * An option specific to a tracer. This is a boolean value. * The bit is the bit index that sets its value on the * flags value in struct tracer_flags. */ struct tracer_opt { const char *name; /* Will appear on the trace_options file */ u32 bit; /* Mask assigned in val field in tracer_flags */ }; /* * The set of specific options for a tracer. Your tracer * have to set the initial value of the flags val. */ struct tracer_flags { u32 val; struct tracer_opt *opts; struct tracer *trace; }; /* Makes more easy to define a tracer opt */ #define TRACER_OPT(s, b) .name = #s, .bit = b struct trace_option_dentry { struct tracer_opt *opt; struct tracer_flags *flags; struct trace_array *tr; struct dentry *entry; }; /** * struct tracer - a specific tracer and its callbacks to interact with tracefs * @name: the name chosen to select it on the available_tracers file * @init: called when one switches to this tracer (echo name > current_tracer) * @reset: called when one switches to another tracer * @start: called when tracing is unpaused (echo 1 > tracing_on) * @stop: called when tracing is paused (echo 0 > tracing_on) * @update_thresh: called when tracing_thresh is updated * @open: called when the trace file is opened * @pipe_open: called when the trace_pipe file is opened * @close: called when the trace file is released * @pipe_close: called when the trace_pipe file is released * @read: override the default read callback on trace_pipe * @splice_read: override the default splice_read callback on trace_pipe * @selftest: selftest to run on boot (see trace_selftest.c) * @print_headers: override the first lines that describe your columns * @print_line: callback that prints a trace * @set_flag: signals one of your private flags changed (trace_options file) * @flags: your private flags */ struct tracer { const char *name; int (*init)(struct trace_array *tr); void (*reset)(struct trace_array *tr); void (*start)(struct trace_array *tr); void (*stop)(struct trace_array *tr); int (*update_thresh)(struct trace_array *tr); void (*open)(struct trace_iterator *iter); void (*pipe_open)(struct trace_iterator *iter); void (*close)(struct trace_iterator *iter); void (*pipe_close)(struct trace_iterator *iter); ssize_t (*read)(struct trace_iterator *iter, struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos); ssize_t (*splice_read)(struct trace_iterator *iter, struct file *filp, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags); #ifdef CONFIG_FTRACE_STARTUP_TEST int (*selftest)(struct tracer *trace, struct trace_array *tr); #endif void (*print_header)(struct seq_file *m); enum print_line_t (*print_line)(struct trace_iterator *iter); /* If you handled the flag setting, return 0 */ int (*set_flag)(struct trace_array *tr, u32 old_flags, u32 bit, int set); /* Return 0 if OK with change, else return non-zero */ int (*flag_changed)(struct trace_array *tr, u32 mask, int set); struct tracer *next; struct tracer_flags *flags; int enabled; int ref; bool print_max; bool allow_instances; #ifdef CONFIG_TRACER_MAX_TRACE bool use_max_tr; #endif /* True if tracer cannot be enabled in kernel param */ bool noboot; }; /* Only current can touch trace_recursion */ /* * For function tracing recursion: * The order of these bits are important. * * When function tracing occurs, the following steps are made: * If arch does not support a ftrace feature: * call internal function (uses INTERNAL bits) which calls... * If callback is registered to the "global" list, the list * function is called and recursion checks the GLOBAL bits. * then this function calls... * The function callback, which can use the FTRACE bits to * check for recursion. * * Now if the arch does not suppport a feature, and it calls * the global list function which calls the ftrace callback * all three of these steps will do a recursion protection. * There's no reason to do one if the previous caller already * did. The recursion that we are protecting against will * go through the same steps again. * * To prevent the multiple recursion checks, if a recursion * bit is set that is higher than the MAX bit of the current * check, then we know that the check was made by the previous * caller, and we can skip the current check. */ enum { TRACE_BUFFER_BIT, TRACE_BUFFER_NMI_BIT, TRACE_BUFFER_IRQ_BIT, TRACE_BUFFER_SIRQ_BIT, /* Start of function recursion bits */ TRACE_FTRACE_BIT, TRACE_FTRACE_NMI_BIT, TRACE_FTRACE_IRQ_BIT, TRACE_FTRACE_SIRQ_BIT, /* INTERNAL_BITs must be greater than FTRACE_BITs */ TRACE_INTERNAL_BIT, TRACE_INTERNAL_NMI_BIT, TRACE_INTERNAL_IRQ_BIT, TRACE_INTERNAL_SIRQ_BIT, TRACE_BRANCH_BIT, /* * Abuse of the trace_recursion.