tracing: Call arch_init_ftrace_syscalls at boot
Call arch_init_ftrace_syscalls at boot, so we can determine early the
set of syscalls for the syscall trace events.
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 afb31d7..0d93d40 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -516,31 +516,24 @@
return -1;
}
-void arch_init_ftrace_syscalls(void)
+static int __init arch_init_ftrace_syscalls(void)
{
int i;
struct syscall_metadata *meta;
unsigned long **psys_syscall_table = &sys_call_table;
- static atomic_t refs;
-
- if (atomic_inc_return(&refs) != 1)
- goto end;
syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) *
FTRACE_SYSCALL_MAX, GFP_KERNEL);
if (!syscalls_metadata) {
WARN_ON(1);
- return;
+ return -ENOMEM;
}
for (i = 0; i < FTRACE_SYSCALL_MAX; i++) {
meta = find_syscall_meta(psys_syscall_table[i]);
syscalls_metadata[i] = meta;
}
- return;
-
- /* Paranoid: avoid overflow */
-end:
- atomic_dec(&refs);
+ return 0;
}
+arch_initcall(arch_init_ftrace_syscalls);
#endif
diff --git a/include/trace/syscall.h b/include/trace/syscall.h
index 8cfe515..c55fcce 100644
--- a/include/trace/syscall.h
+++ b/include/trace/syscall.h
@@ -19,7 +19,6 @@
};
#ifdef CONFIG_FTRACE_SYSCALLS
-extern void arch_init_ftrace_syscalls(void);
extern struct syscall_metadata *syscall_nr_to_meta(int nr);
extern void start_ftrace_syscalls(void);
extern void stop_ftrace_syscalls(void);
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 5e57964..08aed43 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -106,7 +106,6 @@
if (++refcount != 1)
goto unlock;
- arch_init_ftrace_syscalls();
read_lock_irqsave(&tasklist_lock, flags);
do_each_thread(g, t) {