Commit-ID: b8007ef7422270864eae523cb38d7522a53a94d3 Gitweb: http://git.kernel.org/tip/b8007ef7422270864eae523cb38d7522a53a94d3 Author: Lai Jiangshan <laijs@xxxxxxxxxxxxxx> AuthorDate: Tue, 3 Nov 2009 13:45:32 +0800 Committer: Steven Rostedt <rostedt@xxxxxxxxxxx> CommitDate: Wed, 25 Nov 2009 14:20:06 -0500 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@xxxxxxxxxxxxxx> LKML-Reference: <4AEFC37C.5080609@xxxxxxxxxxxxxx> Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> --- include/trace/events/syscalls.h | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/include/trace/events/syscalls.h b/include/trace/events/syscalls.h index 397dff2..fb726ac 100644 --- a/include/trace/events/syscalls.h +++ b/include/trace/events/syscalls.h @@ -1,5 +1,6 @@ #undef TRACE_SYSTEM -#define TRACE_SYSTEM syscalls +#define TRACE_SYSTEM raw_syscalls +#define TRACE_INCLUDE_FILE syscalls #if !defined(_TRACE_EVENTS_SYSCALLS_H) || defined(TRACE_HEADER_MULTI_READ) #define _TRACE_EVENTS_SYSCALLS_H -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
|