tracing: add format files for ftrace default entries

Impact: allow user apps to read binary format of basic ftrace entries

Currently, only defined raw events export their formats so a binary
reader can parse them. There's no reason that the default ftrace entries
can't export their formats.

This patch adds a subsystem called "ftrace" in the events directory
that includes the ftrace entries for basic ftrace recorded items.

These only have three files in the events directory:

 type             : printf
 available_types  : printf
 format           : format for the event entry

For example:

 # cat /debug/tracing/events/ftrace/wakeup/format
name: wakeup
ID: 3
format:
        field:unsigned char type;       offset:0;       size:1;
        field:unsigned char flags;      offset:1;       size:1;
        field:unsigned char preempt_count;      offset:2;       size:1;
        field:int pid;  offset:4;       size:4;
        field:int tgid; offset:8;       size:4;

        field:unsigned int prev_pid;    offset:12;      size:4;
        field:unsigned char prev_prio;  offset:16;      size:1;
        field:unsigned char prev_state; offset:17;      size:1;
        field:unsigned int next_pid;    offset:20;      size:4;
        field:unsigned char next_prio;  offset:24;      size:1;
        field:unsigned char next_state; offset:25;      size:1;
        field:unsigned int next_cpu;    offset:28;      size:4;

print fmt: "%u:%u:%u  ==+ %u:%u:%u [%03u]"

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This commit is contained in:
Steven Rostedt 2009-03-05 21:35:29 -05:00
parent 33b0c229e3
commit 770cb24345
5 changed files with 255 additions and 6 deletions

View File

@ -41,5 +41,6 @@ obj-$(CONFIG_WORKQUEUE_TRACER) += trace_workqueue.o
obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o
obj-$(CONFIG_EVENT_TRACER) += trace_events.o
obj-$(CONFIG_EVENT_TRACER) += events.o
obj-$(CONFIG_EVENT_TRACER) += trace_export.o
libftrace-y := ftrace.o

View File

@ -0,0 +1,165 @@
#undef TRACE_SYSTEM
#define TRACE_SYSTEM ftrace
/*
* We cheat and use the proto type field as the ID
* and args as the entry type (minus 'struct')
*/
TRACE_EVENT_FORMAT(function, TRACE_FN, ftrace_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, ip, ip)
TRACE_FIELD(unsigned long, parent_ip, parent_ip)
),
TPRAWFMT(" %lx <-- %lx")
);
TRACE_EVENT_FORMAT(funcgraph_entry, TRACE_GRAPH_ENT,
ftrace_graph_ent_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, graph_ent.func, func)
TRACE_FIELD(int, graph_ent.depth, depth)
),
TPRAWFMT("--> %lx (%d)")
);
TRACE_EVENT_FORMAT(funcgraph_exit, TRACE_GRAPH_RET,
ftrace_graph_ret_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, ret.func, func)
TRACE_FIELD(int, ret.depth, depth)
),
TPRAWFMT("<-- %lx (%d)")
);
TRACE_EVENT_FORMAT(wakeup, TRACE_WAKE, ctx_switch_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned int, prev_pid, prev_pid)
TRACE_FIELD(unsigned char, prev_prio, prev_prio)
TRACE_FIELD(unsigned char, prev_state, prev_state)
TRACE_FIELD(unsigned int, next_pid, next_pid)
TRACE_FIELD(unsigned char, next_prio, next_prio)
TRACE_FIELD(unsigned char, next_state, next_state)
TRACE_FIELD(unsigned int, next_cpu, next_cpu)
),
TPRAWFMT("%u:%u:%u ==+ %u:%u:%u [%03u]")
);
TRACE_EVENT_FORMAT(context_switch, TRACE_CTX, ctx_switch_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned int, prev_pid, prev_pid)
TRACE_FIELD(unsigned char, prev_prio, prev_prio)
TRACE_FIELD(unsigned char, prev_state, prev_state)
TRACE_FIELD(unsigned int, next_pid, next_pid)
TRACE_FIELD(unsigned char, next_prio, next_prio)
TRACE_FIELD(unsigned char, next_state, next_state)
TRACE_FIELD(unsigned int, next_cpu, next_cpu)
),
TPRAWFMT("%u:%u:%u ==+ %u:%u:%u [%03u]")
);
TRACE_EVENT_FORMAT(special, TRACE_SPECIAL, special_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, arg1, arg1)
TRACE_FIELD(unsigned long, arg2, arg2)
TRACE_FIELD(unsigned long, arg3, arg3)
),
TPRAWFMT("(%08lx) (%08lx) (%08lx)")
);
/*
* Stack-trace entry:
*/
/* #define FTRACE_STACK_ENTRIES 8 */
TRACE_EVENT_FORMAT(kernel_stack, TRACE_STACK, stack_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, caller[0], stack0)
TRACE_FIELD(unsigned long, caller[1], stack1)
TRACE_FIELD(unsigned long, caller[2], stack2)
TRACE_FIELD(unsigned long, caller[3], stack3)
TRACE_FIELD(unsigned long, caller[4], stack4)
TRACE_FIELD(unsigned long, caller[5], stack5)
TRACE_FIELD(unsigned long, caller[6], stack6)
TRACE_FIELD(unsigned long, caller[7], stack7)
),
TPRAWFMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
"\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n")
);
TRACE_EVENT_FORMAT(user_stack, TRACE_USER_STACK, userstack_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, caller[0], stack0)
TRACE_FIELD(unsigned long, caller[1], stack1)
TRACE_FIELD(unsigned long, caller[2], stack2)
TRACE_FIELD(unsigned long, caller[3], stack3)
TRACE_FIELD(unsigned long, caller[4], stack4)
TRACE_FIELD(unsigned long, caller[5], stack5)
TRACE_FIELD(unsigned long, caller[6], stack6)
TRACE_FIELD(unsigned long, caller[7], stack7)
),
TPRAWFMT("\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n"
"\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n\t=> (%08lx)\n")
);
TRACE_EVENT_FORMAT(print, TRACE_PRINT, print_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned long, ip, ip)
TRACE_FIELD(unsigned int, depth, depth)
TRACE_FIELD_ZERO_CHAR(buf)
),
TPRAWFMT("%08lx (%d) %s")
);
TRACE_EVENT_FORMAT(branch, TRACE_BRANCH, trace_branch, ignore,
TRACE_STRUCT(
TRACE_FIELD(unsigned int, line, line)
TRACE_FIELD_SPECIAL(char func[TRACE_FUNC_SIZE+1], func, func)
TRACE_FIELD_SPECIAL(char file[TRACE_FUNC_SIZE+1], file, file)
TRACE_FIELD(char, correct, correct)
),
TPRAWFMT("%u:%s:%s (%u)")
);
TRACE_EVENT_FORMAT(hw_branch, TRACE_HW_BRANCHES, hw_branch_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(u64, from, from)
TRACE_FIELD(u64, to, to)
),
TPRAWFMT("from: %llx to: %llx")
);
TRACE_EVENT_FORMAT(power, TRACE_POWER, trace_power, ignore,
TRACE_STRUCT(
TRACE_FIELD(ktime_t, state_data.stamp, stamp)
TRACE_FIELD(ktime_t, state_data.end, end)
TRACE_FIELD(int, state_data.type, type)
TRACE_FIELD(int, state_data.state, state)
),
TPRAWFMT("%llx->%llx type:%u state:%u")
);
TRACE_EVENT_FORMAT(kmem_alloc, TRACE_KMEM_ALLOC, kmemtrace_alloc_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id)
TRACE_FIELD(unsigned long, call_site, call_site)
TRACE_FIELD(const void *, ptr, ptr)
TRACE_FIELD(size_t, bytes_req, bytes_req)
TRACE_FIELD(size_t, bytes_alloc, bytes_alloc)
TRACE_FIELD(gfp_t, gfp_flags, gfp_flags)
TRACE_FIELD(int, node, node)
),
TPRAWFMT("type:%u call_site:%lx ptr:%p req:%lu alloc:%lu"
" flags:%x node:%d")
);
TRACE_EVENT_FORMAT(kmem_free, TRACE_KMEM_FREE, kmemtrace_free_entry, ignore,
TRACE_STRUCT(
TRACE_FIELD(enum kmemtrace_type_id, type_id, type_id)
TRACE_FIELD(unsigned long, call_site, call_site)
TRACE_FIELD(const void *, ptr, ptr)
),
TPRAWFMT("type:%u call_site:%lx ptr:%p")
);
#undef TRACE_SYSTEM

View File

@ -656,11 +656,13 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events)
return -1;
}
entry = debugfs_create_file("enable", 0644, call->dir, call,
&ftrace_enable_fops);
if (!entry)
pr_warning("Could not create debugfs "
"'%s/enable' entry\n", call->name);
if (call->regfunc) {
entry = debugfs_create_file("enable", 0644, call->dir, call,
&ftrace_enable_fops);
if (!entry)
pr_warning("Could not create debugfs "
"'%s/enable' entry\n", call->name);
}
/* Only let type be writable, if we can change it */
entry = debugfs_create_file("type",

View File

@ -0,0 +1,81 @@
/*
* trace_export.c - export basic ftrace utilities to user space
*
* Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
*/
#include <linux/stringify.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include "trace_output.h"
#include "trace_format.h"
#undef TRACE_FIELD_ZERO_CHAR
#define TRACE_FIELD_ZERO_CHAR(item) \
ret = trace_seq_printf(s, "\tfield: char " #item ";\t" \
"offset:%lu;\tsize:0;\n", \
offsetof(typeof(field), item)); \
if (!ret) \
return 0;
#undef TPRAWFMT
#define TPRAWFMT(args...) args
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
static int \
ftrace_format_##call(struct trace_seq *s) \
{ \
struct args field; \
int ret; \
\
tstruct; \
\
trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt); \
\
return ret; \
}
#include "trace_event_types.h"
#undef TRACE_ZERO_CHAR
#define TRACE_ZERO_CHAR(arg)
#undef TRACE_FIELD
#define TRACE_FIELD(type, item, assign)\
entry->item = assign;
#undef TRACE_FIELD
#define TRACE_FIELD(type, item, assign)\
entry->item = assign;
#undef TPCMD
#define TPCMD(cmd...) cmd
#undef TRACE_ENTRY
#define TRACE_ENTRY entry
#undef TRACE_FIELD_SPECIAL
#define TRACE_FIELD_SPECIAL(type_item, item, cmd) \
cmd;
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
\
static struct ftrace_event_call __used \
__attribute__((__aligned__(4))) \
__attribute__((section("_ftrace_events"))) event_##call = { \
.name = #call, \
.id = proto, \
.system = __stringify(TRACE_SYSTEM), \
.show_format = ftrace_format_##call, \
}
#include "trace_event_types.h"

View File

@ -40,7 +40,7 @@
#undef TRACE_EVENT_FORMAT
#define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt) \
int \
static int \
ftrace_format_##call(struct trace_seq *s) \
{ \
struct ftrace_raw_##call field; \