From: Ian Munsie Date: Thu, 3 Feb 2011 03:27:25 +0000 (+1100) Subject: tracing/syscalls: Early terminate search for sys_ni_syscall X-Git-Tag: v2.6.39-rc1~510^2~63^2~5 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=ae07f551c42d6e4162436ca452a199deac9dab4d;p=linux-block.git tracing/syscalls: Early terminate search for sys_ni_syscall Many system calls are unimplemented and mapped to sys_ni_syscall, but at boot ftrace would still search through every syscall metadata entry for a match which wouldn't be there. This patch adds causes the search to terminate early if the system call is not mapped. Signed-off-by: Ian Munsie LKML-Reference: <1296703645-18718-7-git-send-email-imunsie@au1.ibm.com> Signed-off-by: Steven Rostedt --- diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 86a23e7de031..ee7b5a0bb9f8 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -85,6 +85,9 @@ find_syscall_meta(unsigned long syscall) stop = __stop_syscalls_metadata; kallsyms_lookup(syscall, NULL, NULL, NULL, str); + if (arch_syscall_match_sym_name(str, "sys_ni_syscall")) + return NULL; + for ( ; start < stop; start++) { if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) return *start;