2009-08-24 14:43:14 -07:00
# undef TRACE_SYSTEM
tracing: Separate raw syscall from syscall tracer
The current syscall tracer mixes raw syscalls and real syscalls.
echo 1 > events/syscalls/enable
And we get these from the output:
(XXXX insteads " grep-20914 [001] 588211.446347" .. etc)
XXXX: sys_read(fd: 3, buf: 80609a8, count: 7000)
XXXX: sys_enter: NR 3 (3, 80609a8, 7000, a, 1000, bfce8ef8)
XXXX: sys_read -> 0x138
XXXX: sys_exit: NR 3 = 312
XXXX: sys_read(fd: 3, buf: 8060ae0, count: 7000)
XXXX: sys_enter: NR 3 (3, 8060ae0, 7000, a, 1000, bfce8ef8)
XXXX: sys_read -> 0x138
XXXX: sys_exit: NR 3 = 312
There are 2 drawbacks here.
A) two almost identical records are saved in ringbuffer
when a syscall enters or exits. (4 records for every syscall)
This wastes precious space in the ring buffer.
B) the lines including "sys_enter/sys_exit" produces
hardly any useful information for the output (no labels).
The user can use this method to prevent these drawbacks:
echo 1 > events/syscalls/enable
echo 0 > events/syscalls/sys_enter/enable
echo 0 > events/syscalls/sys_exit/enable
But this is not user friendly. So we separate raw syscall
from syscall tracer.
After this fix applied:
syscall tracer's output (echo 1 > events/syscalls/enable):
XXXX: sys_read(fd: 3, buf: bfe87d88, count: 200)
XXXX: sys_read -> 0x200
XXXX: sys_fstat64(fd: 3, statbuf: bfe87c98)
XXXX: sys_fstat64 -> 0x0
XXXX: sys_close(fd: 3)
raw syscall tracer's output (echo 1 > events/raw_syscalls/enable):
XXXX: sys_enter: NR 175 (0, bf92bf18, bf92bf98, 8, b748cff4, bf92bef8)
XXXX: sys_exit: NR 175 = 0
XXXX: sys_enter: NR 175 (2, bf92bf98, 0, 8, b748cff4, bf92bef8)
XXXX: sys_exit: NR 175 = 0
XXXX: sys_enter: NR 3 (9, bf927f9c, 4000, b77e2518, b77dce60, bf92bff8)
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <4AEFC37C.5080609@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-11-03 13:45:32 +08:00
# define TRACE_SYSTEM raw_syscalls
# define TRACE_INCLUDE_FILE syscalls
2009-08-24 14:43:14 -07:00
# if !defined(_TRACE_EVENTS_SYSCALLS_H) || defined(TRACE_HEADER_MULTI_READ)
# define _TRACE_EVENTS_SYSCALLS_H
# include <linux/tracepoint.h>
# include <asm/ptrace.h>
# include <asm/syscall.h>
# ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
extern void syscall_regfunc ( void ) ;
extern void syscall_unregfunc ( void ) ;
TRACE_EVENT_FN ( sys_enter ,
TP_PROTO ( struct pt_regs * regs , long id ) ,
TP_ARGS ( regs , id ) ,
TP_STRUCT__entry (
__field ( long , id )
__array ( unsigned long , args , 6 )
) ,
TP_fast_assign (
__entry - > id = id ;
syscall_get_arguments ( current , regs , 0 , 6 , __entry - > args ) ;
) ,
TP_printk ( " NR %ld (%lx, %lx, %lx, %lx, %lx, %lx) " ,
__entry - > id ,
__entry - > args [ 0 ] , __entry - > args [ 1 ] , __entry - > args [ 2 ] ,
__entry - > args [ 3 ] , __entry - > args [ 4 ] , __entry - > args [ 5 ] ) ,
syscall_regfunc , syscall_unregfunc
) ;
TRACE_EVENT_FN ( sys_exit ,
TP_PROTO ( struct pt_regs * regs , long ret ) ,
TP_ARGS ( regs , ret ) ,
TP_STRUCT__entry (
__field ( long , id )
__field ( long , ret )
) ,
TP_fast_assign (
__entry - > id = syscall_get_nr ( current , regs ) ;
__entry - > ret = ret ;
) ,
TP_printk ( " NR %ld = %ld " ,
__entry - > id , __entry - > ret ) ,
syscall_regfunc , syscall_unregfunc
) ;
# endif /* CONFIG_HAVE_SYSCALL_TRACEPOINTS */
# endif /* _TRACE_EVENTS_SYSCALLS_H */
/* This part must be outside protection */
# include <trace/define_trace.h>