[for-next][PATCH 10/29] tracing: Change the function format to display function names by perf

From: Steven Rostedt
Date: Wed Feb 20 2019 - 13:38:52 EST


From: Changbin Du <changbin.du@xxxxxxxxx>

Here is an example for this change.

$ sudo perf record -e 'ftrace:function' --filter='ip==schedule'
$ sudo perf report

The output of perf before this patch:

\# Samples: 100 of event 'ftrace:function'
\# Event count (approx.): 100
\#
\# Overhead Trace output
\# ........ ......................................
\#
51.00% ffffffff81f6aaa0 <-- ffffffff81158e8d
29.00% ffffffff81f6aaa0 <-- ffffffff8116ccb2
8.00% ffffffff81f6aaa0 <-- ffffffff81f6f2ed
4.00% ffffffff81f6aaa0 <-- ffffffff811628db
4.00% ffffffff81f6aaa0 <-- ffffffff81f6ec5b
2.00% ffffffff81f6aaa0 <-- ffffffff81f6f21a
1.00% ffffffff81f6aaa0 <-- ffffffff811b04af
1.00% ffffffff81f6aaa0 <-- ffffffff8143ce17

After this patch:

\# Samples: 36 of event 'ftrace:function'
\# Event count (approx.): 36
\#
\# Overhead Trace output
\# ........ ............................................
\#
38.89% schedule <-- schedule_hrtimeout_range_clock
27.78% schedule <-- worker_thread
13.89% schedule <-- schedule_timeout
11.11% schedule <-- smpboot_thread_fn
5.56% schedule <-- rcu_gp_kthread
2.78% schedule <-- exit_to_usermode_loop

Link: http://lkml.kernel.org/r/20190209161919.32350-1-changbin.du@xxxxxxxxx

Signed-off-by: Changbin Du <changbin.du@xxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
kernel/trace/trace_entries.h | 41 +++++++++++++++++-------------------
1 file changed, 19 insertions(+), 22 deletions(-)

diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index 06bb2fd9a56c..fc8e97328e54 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -65,7 +65,8 @@ FTRACE_ENTRY_REG(function, ftrace_entry,
__field( unsigned long, parent_ip )
),

- F_printk(" %lx <-- %lx", __entry->ip, __entry->parent_ip),
+ F_printk(" %ps <-- %ps",
+ (void *)__entry->ip, (void *)__entry->parent_ip),

FILTER_TRACE_FN,

@@ -83,7 +84,7 @@ FTRACE_ENTRY_PACKED(funcgraph_entry, ftrace_graph_ent_entry,
__field_desc( int, graph_ent, depth )
),

- F_printk("--> %lx (%d)", __entry->func, __entry->depth),
+ F_printk("--> %ps (%d)", (void *)__entry->func, __entry->depth),

FILTER_OTHER
);
@@ -102,8 +103,8 @@ FTRACE_ENTRY_PACKED(funcgraph_exit, ftrace_graph_ret_entry,
__field_desc( int, ret, depth )
),

- F_printk("<-- %lx (%d) (start: %llx end: %llx) over: %d",
- __entry->func, __entry->depth,
+ F_printk("<-- %ps (%d) (start: %llx end: %llx) over: %d",
+ (void *)__entry->func, __entry->depth,
__entry->calltime, __entry->rettime,
__entry->depth),

@@ -167,12 +168,6 @@ FTRACE_ENTRY_DUP(wakeup, ctx_switch_entry,

#define FTRACE_STACK_ENTRIES 8

-#ifndef CONFIG_64BIT
-# define IP_FMT "%08lx"
-#else
-# define IP_FMT "%016lx"
-#endif
-
FTRACE_ENTRY(kernel_stack, stack_entry,

TRACE_STACK,
@@ -182,12 +177,13 @@ FTRACE_ENTRY(kernel_stack, stack_entry,
__dynamic_array(unsigned long, caller )
),

- F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
- "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
- "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
- __entry->caller[0], __entry->caller[1], __entry->caller[2],
- __entry->caller[3], __entry->caller[4], __entry->caller[5],
- __entry->caller[6], __entry->caller[7]),
+ F_printk("\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+ "\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+ "\t=> %ps\n\t=> %ps\n",
+ (void *)__entry->caller[0], (void *)__entry->caller[1],
+ (void *)__entry->caller[2], (void *)__entry->caller[3],
+ (void *)__entry->caller[4], (void *)__entry->caller[5],
+ (void *)__entry->caller[6], (void *)__entry->caller[7]),

FILTER_OTHER
);
@@ -201,12 +197,13 @@ FTRACE_ENTRY(user_stack, userstack_entry,
__array( unsigned long, caller, FTRACE_STACK_ENTRIES )
),

- F_printk("\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
- "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n"
- "\t=> (" IP_FMT ")\n\t=> (" IP_FMT ")\n",
- __entry->caller[0], __entry->caller[1], __entry->caller[2],
- __entry->caller[3], __entry->caller[4], __entry->caller[5],
- __entry->caller[6], __entry->caller[7]),
+ F_printk("\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+ "\t=> %ps\n\t=> %ps\n\t=> %ps\n"
+ "\t=> %ps\n\t=> %ps\n",
+ (void *)__entry->caller[0], (void *)__entry->caller[1],
+ (void *)__entry->caller[2], (void *)__entry->caller[3],
+ (void *)__entry->caller[4], (void *)__entry->caller[5],
+ (void *)__entry->caller[6], (void *)__entry->caller[7]),

FILTER_OTHER
);
--
2.20.1