From: Arnaldo Carvalho de Melo <[email protected]> The 'parent_tidptr', 'child_tidptr' and 'tls' arguments to the 'clone' syscall are only used when certain flags are set in 'flags', suppress them when those aren't there.
E.g: 9886.919 (0.236 ms): fetchmail/19298 clone(flags: CHILD_CLEARTID|CHILD_SETTID|0x11, child_stack: 0, child_tidptr: 0x7fe43f468590) = 19608 (fetchmail) 12876.052 (0.249 ms): qemu-system-x8/21238 clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7f48117fc770, parent_tidptr: 0x7f48117ff9d0, child_tidptr: 0x7f48117ff9d0, tls: 0x7f48117ff700) = 19611 (qemu-system-x86) 12876.555 (0.048 ms): worker/19611 clone(flags: VM|FS|FILES|SIGHAND|THREAD|SYSVSEM|SETTLS|PARENT_SETTID|CHILD_CLEARTID, child_stack: 0x7f480f7f8770, parent_tidptr: 0x7f480f7fb9d0, child_tidptr: 0x7f480f7fb9d0, tls: 0x7f480f7fb700) = 19612 (worker) 16575.240 (0.469 ms): fetchmail/19298 clone(flags: CHILD_CLEARTID|CHILD_SETTID|0x11, child_stack: 0, child_tidptr: 0x7fe43f468590) = 19613 (fetchmail) 20797.270 (0.335 ms): fetchmail/19298 clone(flags: CHILD_CLEARTID|CHILD_SETTID|0x11, child_stack: 0, child_tidptr: 0x7fe43f468590) = 19614 (fetchmail) 21228.585 (0.501 ms): vim/19519 clone(flags: CHILD_CLEARTID|CHILD_SETTID|0x11, child_stack: 0, child_tidptr: 0x7fbad6ac27d0) = 19615 (vim) 21232.193 (0.137 ms): bash/19615 clone(flags: CHILD_CLEARTID|CHILD_SETTID|0x11, child_stack: 0, child_tidptr: 0x7fad8bff49d0) = 19616 (bash) Cc: Adrian Hunter <[email protected]> Cc: David Ahern <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Wang Nan <[email protected]> Link: http://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/trace/beauty/clone.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/tools/perf/trace/beauty/clone.c b/tools/perf/trace/beauty/clone.c index ab982a7c63bb..d64d049ab991 100644 --- a/tools/perf/trace/beauty/clone.c +++ b/tools/perf/trace/beauty/clone.c @@ -54,5 +54,22 @@ static size_t clone__scnprintf_flags(unsigned long flags, char *bf, size_t size) size_t syscall_arg__scnprintf_clone_flags(char *bf, size_t size, struct syscall_arg *arg) { - return clone__scnprintf_flags(arg->val, bf, size); + unsigned long flags = arg->val; + enum syscall_clone_args { + SCC_FLAGS = (1 << 0), + SCC_CHILD_STACK = (1 << 1), + SCC_PARENT_TIDPTR = (1 << 2), + SCC_CHILD_TIDPTR = (1 << 3), + SCC_TLS = (1 << 4), + }; + if (!(flags & CLONE_PARENT_SETTID)) + arg->mask |= SCC_PARENT_TIDPTR; + + if (!(flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID))) + arg->mask |= SCC_CHILD_TIDPTR; + + if (!(flags & CLONE_SETTLS)) + arg->mask |= SCC_TLS; + + return clone__scnprintf_flags(flags, bf, size); } -- 2.9.4
