tracing: Map syscall name to number

Add a new function to support translating a syscall name to number at
runtime.
This allows the syscall event tracer to map syscall names to number.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Jiaying Zhang <jiayingz@google.com>
Cc: Martin Bligh <mbligh@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 8e9663413b7f1c863535e6538f0612ca4b71bb55..afb31d72618de0da75d622af4868d17043606400 100644 (file)
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -500,6 +500,22 @@ struct syscall_metadata *syscall_nr_to_meta(int nr)
        return syscalls_metadata[nr];
 }
 
+int syscall_name_to_nr(char *name)
+{
+       int i;
+
+       if (!syscalls_metadata)
+               return -1;
+
+       for (i = 0; i < FTRACE_SYSCALL_MAX; i++) {
+               if (syscalls_metadata[i]) {
+                       if (!strcmp(syscalls_metadata[i]->name, name))
+                               return i;
+               }
+       }
+       return -1;
+}
+
 void arch_init_ftrace_syscalls(void)
 {
        int i;