[PATCH 02/12] call arch_init_ftrace_syscalls at boot

Jason Baron
2009-08-10T20:54:43Z

Call arch_init_ftrace_syscalls at boot, so we can determine the set of syscalls
for the syscall trace events.

Signed-off-by: Jason Baron <jbaron@redhat.com>

---
arch/x86/kernel/ftrace.c | 15 ++++-----------
include/trace/syscall.h | 1 -
kernel/trace/trace_syscalls.c | 1 -
3 files changed, 4 insertions(+), 13 deletions(-)

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 @@ int syscall_name_to_nr(char *name)
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 @@ struct syscall_metadata {
};

#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 @@ void start_ftrace_syscalls(void)
if (++refcount != 1)
goto unlock;

- arch_init_ftrace_syscalls();
read_lock_irqsave(&tasklist_lock, flags);

do_each_thread(g, t) {
--
1.6.2.5