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b8007ef742
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> |
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| .. | ||
| events | ||
| boot.h | ||
| define_trace.h | ||
| ftrace.h | ||
| syscall.h | ||