2012/2/6 Greg KH gregkh@linuxfoundation.org:
On Mon, Feb 06, 2012 at 10:59:09PM +0400, Anton Vorontsov wrote:
On Mon, Feb 06, 2012 at 08:35:42AM -0800, Greg KH wrote: [...]
-extern struct task_struct *find_lock_task_mm(struct task_struct *p); +extern struct task_struct *__find_lock_task_mm(struct task_struct *p);
+#define find_lock_task_mm(p) \ +({ \
- struct task_struct *__ret; \
- \
- __cond_lock(&(p)->alloc_lock, __ret = __find_lock_task_mm(p)); \
- __ret; \
+})
Please use the proper "do...while" style thing here for multi-line, complex #defines like the rest of the kernel does so that you don't end up debugging horrible problems later.
Unfortunately this isn't possible in this case. Unlike '({})' GCC extension, do-while statement does not evaluate to a value, i.e. 'x = do { 123; } while (0);' is illegal.
Ah, you are right, my bad, sorry about that.
greg k-h
Some __cond_lock() caller are inline functions. Is this bad? inline function is always recommended than macros.