patch-2.4.20 linux-2.4.20/arch/s390x/kernel/process.c

• Lines: 44
• Date: Thu Nov 28 15:53:11 2002
• Orig file: linux-2.4.19/arch/s390x/kernel/process.c
• Orig date: Fri Aug 2 17:39:43 2002

diff -urN linux-2.4.19/arch/s390x/kernel/process.c linux-2.4.20/arch/s390x/kernel/process.c
@@ -183,6 +183,43 @@
         return 0;
 }
 
+/* 
+ * Allocation and freeing of basic task resources. 
+ * The task struct and the stack go together.
+ *
+ * NOTE: An order-2 allocation can easily fail.  If this
+ *       happens we fall back to using vmalloc ...
+ */
+
+struct task_struct *alloc_task_struct(void)
+{
+	struct task_struct *tsk = __get_free_pages(GFP_KERNEL, 2);
+	if (!tsk)
+		tsk = vmalloc(16384);
+	if (!tsk)
+		return NULL;
+
+        atomic_set((atomic_t *)(tsk + 1), 1);
+        return tsk;
+}
+
+void free_task_struct(struct task_struct *tsk)
+{
+	if (atomic_dec_and_test((atomic_t *)(tsk + 1)))
+	{
+		if ((unsigned long)tsk < VMALLOC_START)
+			free_pages((unsigned long)tsk, 2);
+		else
+			vfree(tsk);
+	}
+}
+
+void get_task_struct(struct task_struct *tsk)
+{
+	atomic_inc((atomic_t *)(tsk + 1));
+}
+
+
 asmlinkage int sys_fork(struct pt_regs regs)
 {
         return do_fork(SIGCHLD, regs.gprs[15], &regs, 0);