linux/include/trace/ftrace.h

771 lines
20 KiB
C

/*
* Stage 1 of the trace events.
*
* Override the macros in <trace/trace_events.h> to include the following:
*
* struct ftrace_raw_<call> {
* struct trace_entry ent;
* <type> <item>;
* <type2> <item2>[<len>];
* [...]
* };
*
* The <type> <item> is created by the __field(type, item) macro or
* the __array(type2, item2, len) macro.
* We simply do "type item;", and that will create the fields
* in the structure.
*/
#include <linux/ftrace_event.h>
#undef __field
#define __field(type, item) type item;
#undef __field_ext
#define __field_ext(type, item, filter_type) type item;
#undef __array
#define __array(type, item, len) type item[len];
#undef __dynamic_array
#define __dynamic_array(type, item, len) u32 __data_loc_##item;
#undef __string
#define __string(item, src) __dynamic_array(char, item, -1)
#undef TP_STRUCT__entry
#define TP_STRUCT__entry(args...) args
#undef TRACE_EVENT
#define TRACE_EVENT(name, proto, args, tstruct, assign, print) \
struct ftrace_raw_##name { \
struct trace_entry ent; \
tstruct \
char __data[0]; \
}; \
static struct ftrace_event_call event_##name
#undef __cpparg
#define __cpparg(arg...) arg
/* Callbacks are meaningless to ftrace. */
#undef TRACE_EVENT_FN
#define TRACE_EVENT_FN(name, proto, args, tstruct, \
assign, print, reg, unreg) \
TRACE_EVENT(name, __cpparg(proto), __cpparg(args), \
__cpparg(tstruct), __cpparg(assign), __cpparg(print)) \
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/*
* Stage 2 of the trace events.
*
* Include the following:
*
* struct ftrace_data_offsets_<call> {
* u32 <item1>;
* u32 <item2>;
* [...]
* };
*
* The __dynamic_array() macro will create each u32 <item>, this is
* to keep the offset of each array from the beginning of the event.
* The size of an array is also encoded, in the higher 16 bits of <item>.
*/
#undef __field
#define __field(type, item)
#undef __field_ext
#define __field_ext(type, item, filter_type)
#undef __array
#define __array(type, item, len)
#undef __dynamic_array
#define __dynamic_array(type, item, len) u32 item;
#undef __string
#define __string(item, src) __dynamic_array(char, item, -1)
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
struct ftrace_data_offsets_##call { \
tstruct; \
};
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/*
* Setup the showing format of trace point.
*
* int
* ftrace_format_##call(struct trace_seq *s)
* {
* struct ftrace_raw_##call field;
* int ret;
*
* ret = trace_seq_printf(s, #type " " #item ";"
* " offset:%u; size:%u;\n",
* offsetof(struct ftrace_raw_##call, item),
* sizeof(field.type));
*
* }
*/
#undef TP_STRUCT__entry
#define TP_STRUCT__entry(args...) args
#undef __field
#define __field(type, item) \
ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t" \
"offset:%u;\tsize:%u;\n", \
(unsigned int)offsetof(typeof(field), item), \
(unsigned int)sizeof(field.item)); \
if (!ret) \
return 0;
#undef __field_ext
#define __field_ext(type, item, filter_type) __field(type, item)
#undef __array
#define __array(type, item, len) \
ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
"offset:%u;\tsize:%u;\n", \
(unsigned int)offsetof(typeof(field), item), \
(unsigned int)sizeof(field.item)); \
if (!ret) \
return 0;
#undef __dynamic_array
#define __dynamic_array(type, item, len) \
ret = trace_seq_printf(s, "\tfield:__data_loc " #type "[] " #item ";\t"\
"offset:%u;\tsize:%u;\n", \
(unsigned int)offsetof(typeof(field), \
__data_loc_##item), \
(unsigned int)sizeof(field.__data_loc_##item)); \
if (!ret) \
return 0;
#undef __string
#define __string(item, src) __dynamic_array(char, item, -1)
#undef __entry
#define __entry REC
#undef __print_symbolic
#undef __get_dynamic_array
#undef __get_str
#undef TP_printk
#define TP_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
#undef TP_fast_assign
#define TP_fast_assign(args...) args
#undef TP_perf_assign
#define TP_perf_assign(args...)
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, func, print) \
static int \
ftrace_format_##call(struct ftrace_event_call *unused, \
struct trace_seq *s) \
{ \
struct ftrace_raw_##call field __attribute__((unused)); \
int ret = 0; \
\
tstruct; \
\
trace_seq_printf(s, "\nprint fmt: " print); \
\
return ret; \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/*
* Stage 3 of the trace events.
*
* Override the macros in <trace/trace_events.h> to include the following:
*
* enum print_line_t
* ftrace_raw_output_<call>(struct trace_iterator *iter, int flags)
* {
* struct trace_seq *s = &iter->seq;
* struct ftrace_raw_<call> *field; <-- defined in stage 1
* struct trace_entry *entry;
* struct trace_seq *p;
* int ret;
*
* entry = iter->ent;
*
* if (entry->type != event_<call>.id) {
* WARN_ON_ONCE(1);
* return TRACE_TYPE_UNHANDLED;
* }
*
* field = (typeof(field))entry;
*
* p = get_cpu_var(ftrace_event_seq);
* trace_seq_init(p);
* ret = trace_seq_printf(s, <TP_printk> "\n");
* put_cpu();
* if (!ret)
* return TRACE_TYPE_PARTIAL_LINE;
*
* return TRACE_TYPE_HANDLED;
* }
*
* This is the method used to print the raw event to the trace
* output format. Note, this is not needed if the data is read
* in binary.
*/
#undef __entry
#define __entry field
#undef TP_printk
#define TP_printk(fmt, args...) fmt "\n", args
#undef __get_dynamic_array
#define __get_dynamic_array(field) \
((void *)__entry + (__entry->__data_loc_##field & 0xffff))
#undef __get_str
#define __get_str(field) (char *)__get_dynamic_array(field)
#undef __print_flags
#define __print_flags(flag, delim, flag_array...) \
({ \
static const struct trace_print_flags __flags[] = \
{ flag_array, { -1, NULL }}; \
ftrace_print_flags_seq(p, delim, flag, __flags); \
})
#undef __print_symbolic
#define __print_symbolic(value, symbol_array...) \
({ \
static const struct trace_print_flags symbols[] = \
{ symbol_array, { -1, NULL }}; \
ftrace_print_symbols_seq(p, value, symbols); \
})
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
static enum print_line_t \
ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \
{ \
struct trace_seq *s = &iter->seq; \
struct ftrace_raw_##call *field; \
struct trace_entry *entry; \
struct trace_seq *p; \
int ret; \
\
entry = iter->ent; \
\
if (entry->type != event_##call.id) { \
WARN_ON_ONCE(1); \
return TRACE_TYPE_UNHANDLED; \
} \
\
field = (typeof(field))entry; \
\
p = &get_cpu_var(ftrace_event_seq); \
trace_seq_init(p); \
ret = trace_seq_printf(s, #call ": " print); \
put_cpu(); \
if (!ret) \
return TRACE_TYPE_PARTIAL_LINE; \
\
return TRACE_TYPE_HANDLED; \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
#undef __field_ext
#define __field_ext(type, item, filter_type) \
ret = trace_define_field(event_call, #type, #item, \
offsetof(typeof(field), item), \
sizeof(field.item), \
is_signed_type(type), filter_type); \
if (ret) \
return ret;
#undef __field
#define __field(type, item) __field_ext(type, item, FILTER_OTHER)
#undef __array
#define __array(type, item, len) \
BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
ret = trace_define_field(event_call, #type "[" #len "]", #item, \
offsetof(typeof(field), item), \
sizeof(field.item), 0, FILTER_OTHER); \
if (ret) \
return ret;
#undef __dynamic_array
#define __dynamic_array(type, item, len) \
ret = trace_define_field(event_call, "__data_loc " #type "[]", #item, \
offsetof(typeof(field), __data_loc_##item), \
sizeof(field.__data_loc_##item), 0, \
FILTER_OTHER);
#undef __string
#define __string(item, src) __dynamic_array(char, item, -1)
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, func, print) \
static int \
ftrace_define_fields_##call(struct ftrace_event_call *event_call) \
{ \
struct ftrace_raw_##call field; \
int ret; \
\
ret = trace_define_common_fields(event_call); \
if (ret) \
return ret; \
\
tstruct; \
\
return ret; \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/*
* remember the offset of each array from the beginning of the event.
*/
#undef __entry
#define __entry entry
#undef __field
#define __field(type, item)
#undef __field_ext
#define __field_ext(type, item, filter_type)
#undef __array
#define __array(type, item, len)
#undef __dynamic_array
#define __dynamic_array(type, item, len) \
__data_offsets->item = __data_size + \
offsetof(typeof(*entry), __data); \
__data_offsets->item |= (len * sizeof(type)) << 16; \
__data_size += (len) * sizeof(type);
#undef __string
#define __string(item, src) __dynamic_array(char, item, strlen(src) + 1) \
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
static inline int ftrace_get_offsets_##call( \
struct ftrace_data_offsets_##call *__data_offsets, proto) \
{ \
int __data_size = 0; \
struct ftrace_raw_##call __maybe_unused *entry; \
\
tstruct; \
\
return __data_size; \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
#ifdef CONFIG_EVENT_PROFILE
/*
* Generate the functions needed for tracepoint perf_event support.
*
* NOTE: The insertion profile callback (ftrace_profile_<call>) is defined later
*
* static int ftrace_profile_enable_<call>(void)
* {
* return register_trace_<call>(ftrace_profile_<call>);
* }
*
* static void ftrace_profile_disable_<call>(void)
* {
* unregister_trace_<call>(ftrace_profile_<call>);
* }
*
*/
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
\
static void ftrace_profile_##call(proto); \
\
static int ftrace_profile_enable_##call(void) \
{ \
return register_trace_##call(ftrace_profile_##call); \
} \
\
static void ftrace_profile_disable_##call(void) \
{ \
unregister_trace_##call(ftrace_profile_##call); \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
#endif
/*
* Stage 4 of the trace events.
*
* Override the macros in <trace/trace_events.h> to include the following:
*
* static void ftrace_event_<call>(proto)
* {
* event_trace_printk(_RET_IP_, "<call>: " <fmt>);
* }
*
* static int ftrace_reg_event_<call>(void)
* {
* int ret;
*
* ret = register_trace_<call>(ftrace_event_<call>);
* if (!ret)
* pr_info("event trace: Could not activate trace point "
* "probe to <call>");
* return ret;
* }
*
* static void ftrace_unreg_event_<call>(void)
* {
* unregister_trace_<call>(ftrace_event_<call>);
* }
*
*
* For those macros defined with TRACE_EVENT:
*
* static struct ftrace_event_call event_<call>;
*
* static void ftrace_raw_event_<call>(proto)
* {
* struct ring_buffer_event *event;
* struct ftrace_raw_<call> *entry; <-- defined in stage 1
* struct ring_buffer *buffer;
* unsigned long irq_flags;
* int pc;
*
* local_save_flags(irq_flags);
* pc = preempt_count();
*
* event = trace_current_buffer_lock_reserve(&buffer,
* event_<call>.id,
* sizeof(struct ftrace_raw_<call>),
* irq_flags, pc);
* if (!event)
* return;
* entry = ring_buffer_event_data(event);
*
* <assign>; <-- Here we assign the entries by the __field and
* __array macros.
*
* trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc);
* }
*
* static int ftrace_raw_reg_event_<call>(void)
* {
* int ret;
*
* ret = register_trace_<call>(ftrace_raw_event_<call>);
* if (!ret)
* pr_info("event trace: Could not activate trace point "
* "probe to <call>");
* return ret;
* }
*
* static void ftrace_unreg_event_<call>(void)
* {
* unregister_trace_<call>(ftrace_raw_event_<call>);
* }
*
* static struct trace_event ftrace_event_type_<call> = {
* .trace = ftrace_raw_output_<call>, <-- stage 2
* };
*
* static int ftrace_raw_init_event_<call>(void)
* {
* int id;
*
* id = register_ftrace_event(&ftrace_event_type_<call>);
* if (!id)
* return -ENODEV;
* event_<call>.id = id;
* return 0;
* }
*
* static struct ftrace_event_call __used
* __attribute__((__aligned__(4)))
* __attribute__((section("_ftrace_events"))) event_<call> = {
* .name = "<call>",
* .system = "<system>",
* .raw_init = ftrace_raw_init_event_<call>,
* .regfunc = ftrace_reg_event_<call>,
* .unregfunc = ftrace_unreg_event_<call>,
* .show_format = ftrace_format_<call>,
* }
*
*/
#undef TP_FMT
#define TP_FMT(fmt, args...) fmt "\n", ##args
#ifdef CONFIG_EVENT_PROFILE
#define _TRACE_PROFILE_INIT(call) \
.profile_count = ATOMIC_INIT(-1), \
.profile_enable = ftrace_profile_enable_##call, \
.profile_disable = ftrace_profile_disable_##call,
#else
#define _TRACE_PROFILE_INIT(call)
#endif
#undef __entry
#define __entry entry
#undef __field
#define __field(type, item)
#undef __array
#define __array(type, item, len)
#undef __dynamic_array
#define __dynamic_array(type, item, len) \
__entry->__data_loc_##item = __data_offsets.item;
#undef __string
#define __string(item, src) __dynamic_array(char, item, -1) \
#undef __assign_str
#define __assign_str(dst, src) \
strcpy(__get_str(dst), src);
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
\
static struct ftrace_event_call event_##call; \
\
static void ftrace_raw_event_##call(proto) \
{ \
struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
struct ftrace_event_call *event_call = &event_##call; \
struct ring_buffer_event *event; \
struct ftrace_raw_##call *entry; \
struct ring_buffer *buffer; \
unsigned long irq_flags; \
int __data_size; \
int pc; \
\
local_save_flags(irq_flags); \
pc = preempt_count(); \
\
__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
\
event = trace_current_buffer_lock_reserve(&buffer, \
event_##call.id, \
sizeof(*entry) + __data_size, \
irq_flags, pc); \
if (!event) \
return; \
entry = ring_buffer_event_data(event); \
\
\
tstruct \
\
{ assign; } \
\
if (!filter_current_check_discard(buffer, event_call, entry, event)) \
trace_nowake_buffer_unlock_commit(buffer, \
event, irq_flags, pc); \
} \
\
static int ftrace_raw_reg_event_##call(void *ptr) \
{ \
int ret; \
\
ret = register_trace_##call(ftrace_raw_event_##call); \
if (ret) \
pr_info("event trace: Could not activate trace point " \
"probe to " #call "\n"); \
return ret; \
} \
\
static void ftrace_raw_unreg_event_##call(void *ptr) \
{ \
unregister_trace_##call(ftrace_raw_event_##call); \
} \
\
static struct trace_event ftrace_event_type_##call = { \
.trace = ftrace_raw_output_##call, \
}; \
\
static int ftrace_raw_init_event_##call(void) \
{ \
int id; \
\
id = register_ftrace_event(&ftrace_event_type_##call); \
if (!id) \
return -ENODEV; \
event_##call.id = id; \
INIT_LIST_HEAD(&event_##call.fields); \
return 0; \
} \
\
static struct ftrace_event_call __used \
__attribute__((__aligned__(4))) \
__attribute__((section("_ftrace_events"))) event_##call = { \
.name = #call, \
.system = __stringify(TRACE_SYSTEM), \
.event = &ftrace_event_type_##call, \
.raw_init = ftrace_raw_init_event_##call, \
.regfunc = ftrace_raw_reg_event_##call, \
.unregfunc = ftrace_raw_unreg_event_##call, \
.show_format = ftrace_format_##call, \
.define_fields = ftrace_define_fields_##call, \
_TRACE_PROFILE_INIT(call) \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/*
* Define the insertion callback to profile events
*
* The job is very similar to ftrace_raw_event_<call> except that we don't
* insert in the ring buffer but in a perf counter.
*
* static void ftrace_profile_<call>(proto)
* {
* struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
* struct ftrace_event_call *event_call = &event_<call>;
* extern void perf_tp_event(int, u64, u64, void *, int);
* struct ftrace_raw_##call *entry;
* u64 __addr = 0, __count = 1;
* unsigned long irq_flags;
* struct trace_entry *ent;
* int __entry_size;
* int __data_size;
* int __cpu
* int pc;
*
* pc = preempt_count();
*
* __data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
*
* // Below we want to get the aligned size by taking into account
* // the u32 field that will later store the buffer size
* __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),
* sizeof(u64));
* __entry_size -= sizeof(u32);
*
* // Protect the non nmi buffer
* // This also protects the rcu read side
* local_irq_save(irq_flags);
* __cpu = smp_processor_id();
*
* if (in_nmi())
* raw_data = rcu_dereference(trace_profile_buf_nmi);
* else
* raw_data = rcu_dereference(trace_profile_buf);
*
* if (!raw_data)
* goto end;
*
* raw_data = per_cpu_ptr(raw_data, __cpu);
*
* //zero dead bytes from alignment to avoid stack leak to userspace:
* *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL;
* entry = (struct ftrace_raw_<call> *)raw_data;
* ent = &entry->ent;
* tracing_generic_entry_update(ent, irq_flags, pc);
* ent->type = event_call->id;
*
* <tstruct> <- do some jobs with dynamic arrays
*
* <assign> <- affect our values
*
* perf_tp_event(event_call->id, __addr, __count, entry,
* __entry_size); <- submit them to perf counter
*
* }
*/
#ifdef CONFIG_EVENT_PROFILE
#undef __perf_addr
#define __perf_addr(a) __addr = (a)
#undef __perf_count
#define __perf_count(c) __count = (c)
#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
static void ftrace_profile_##call(proto) \
{ \
struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
struct ftrace_event_call *event_call = &event_##call; \
extern void perf_tp_event(int, u64, u64, void *, int); \
struct ftrace_raw_##call *entry; \
u64 __addr = 0, __count = 1; \
unsigned long irq_flags; \
struct trace_entry *ent; \
int __entry_size; \
int __data_size; \
char *raw_data; \
int __cpu; \
int pc; \
\
pc = preempt_count(); \
\
__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
sizeof(u64)); \
__entry_size -= sizeof(u32); \
\
if (WARN_ONCE(__entry_size > FTRACE_MAX_PROFILE_SIZE, \
"profile buffer not large enough")) \
return; \
\
local_irq_save(irq_flags); \
__cpu = smp_processor_id(); \
\
if (in_nmi()) \
raw_data = rcu_dereference(trace_profile_buf_nmi); \
else \
raw_data = rcu_dereference(trace_profile_buf); \
\
if (!raw_data) \
goto end; \
\
raw_data = per_cpu_ptr(raw_data, __cpu); \
\
*(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; \
entry = (struct ftrace_raw_##call *)raw_data; \
ent = &entry->ent; \
tracing_generic_entry_update(ent, irq_flags, pc); \
ent->type = event_call->id; \
\
tstruct \
\
{ assign; } \
\
perf_tp_event(event_call->id, __addr, __count, entry, \
__entry_size); \
\
end: \
local_irq_restore(irq_flags); \
\
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
#endif /* CONFIG_EVENT_PROFILE */
#undef _TRACE_PROFILE_INIT