Attempt to reduce stack usage in time.c (linux-2.6.12-rc1-mm3). Stack
usage was noted using checkstack.pl. Specifically:

Before patch
------------
sys_adjtimex - 128

After patch
-----------
sys_adjtimex - none (register usage only)

Signed-off-by: Yum Rayan <[EMAIL PROTECTED]>

--- a/kernel/time.c     2005-03-25 22:11:06.000000000 -0800
+++ b/kernel/time.c     2005-03-30 16:59:51.000000000 -0800
@@ -413,17 +413,27 @@
 
 asmlinkage long sys_adjtimex(struct timex __user *txc_p)
 {
-       struct timex txc;               /* Local copy of parameter */
-       int ret;
+       struct timex *txc;              /* Local copy of parameter */
+       int retval;
+
+       txc = kmalloc(sizeof(struct timex), GFP_KERNEL);
+       if (!txc)
+               return -ENOMEM;
 
        /* Copy the user data space into the kernel copy
         * structure. But bear in mind that the structures
         * may change
         */
-       if(copy_from_user(&txc, txc_p, sizeof(struct timex)))
-               return -EFAULT;
-       ret = do_adjtimex(&txc);
-       return copy_to_user(txc_p, &txc, sizeof(struct timex)) ? -EFAULT : ret;
+       if(copy_from_user(txc, txc_p, sizeof(struct timex))) {
+               retval = -EFAULT;
+               goto free_txc;
+       }
+       retval = do_adjtimex(txc);
+       if (copy_to_user(txc_p, txc, sizeof(struct timex)))
+               retval = -EFAULT;
+free_txc:
+       kfree(txc);
+       return retval;
 }
 
 inline struct timespec current_kernel_time(void)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to