[PATCH 2/6] ftrace syscalls: Convert redundant syscall_nr checks into WARN_ON
From: Ian Munsie <hidden>
Date: 2011-02-03 03:27:56
Also in:
lkml
Subsystem:
the rest, tracing · Maintainers:
Linus Torvalds, Steven Rostedt, Masami Hiramatsu
From: Ian Munsie <redacted> With the ftrace events now checking if the syscall_nr is valid upon initialisation it should no longer be possible to register or unregister a syscall event without a valid syscall_nr since they should not be created. This adds a WARN_ON_ONCE in the register and unregister functions to locate potential regressions in the future. Signed-off-by: Ian Munsie <redacted> --- kernel/trace/trace_syscalls.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index a66bc13..1a6e8dd 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c@@ -358,7 +358,7 @@ int reg_event_syscall_enter(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return -ENOSYS; mutex_lock(&syscall_trace_lock); if (!sys_refcount_enter)
@@ -376,7 +376,7 @@ void unreg_event_syscall_enter(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return; mutex_lock(&syscall_trace_lock); sys_refcount_enter--;
@@ -392,7 +392,7 @@ int reg_event_syscall_exit(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return -ENOSYS; mutex_lock(&syscall_trace_lock); if (!sys_refcount_exit)
@@ -410,7 +410,7 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return; mutex_lock(&syscall_trace_lock); sys_refcount_exit--;
--
1.7.2.3