[smart] split out part of lwp_new() to lwp_create()

Prev implementation of lwp_new() including the create of lwp object
and the pid allocation. But not every lwp object need a pid.
So this patch split out the business of lwp_new() to improve the
maintainability.

Signed-off-by: Shell <smokewood@qq.com>

components/lwp/lwp.c

@@ -1152,7 +1152,7 @@ pid_t lwp_execve(char *filename, int debug, int argc, char **argv, char **envp)
         return -EACCES;
     }
 
-    lwp = lwp_new();
+    lwp = lwp_create(LWP_CREATE_FLAG_ALLOC_PID);
 
     if (lwp == RT_NULL)
     {

components/lwp/lwp.h

@@ -145,6 +145,7 @@ struct rt_lwp
     unsigned int asid;
 #endif
 };
+typedef struct rt_lwp *rt_lwp_t;
 
 struct rt_lwp *lwp_self(void);
 

components/lwp/lwp_pid.c

@@ -314,53 +314,46 @@ void lwp_user_object_dup(struct rt_lwp *dst_lwp, struct rt_lwp *src_lwp)
     lwp_user_object_unlock(src_lwp);
 }
 
-struct rt_lwp* lwp_new(void)
+rt_lwp_t lwp_create(rt_base_t flags)
 {
     pid_t pid;
     rt_base_t level;
-    struct rt_lwp* lwp = RT_NULL;
-
-    lwp = (struct rt_lwp *)rt_malloc(sizeof(struct rt_lwp));
-    if (lwp == RT_NULL)
-    {
-        return lwp;
-    }
-    memset(lwp, 0, sizeof(*lwp));
-    //lwp->tgroup_leader = RT_NULL;
-    rt_list_init(&lwp->wait_list);
-    lwp->leader = 0;
-    lwp->session = -1;
-    lwp->tty = RT_NULL;
-    rt_list_init(&lwp->t_grp);
-    rt_list_init(&lwp->timer);
-    lwp_user_object_lock_init(lwp);
-    lwp->address_search_head = RT_NULL;
-    rt_wqueue_init(&lwp->wait_queue);
-    lwp->ref = 1;
-
-    lwp_signal_init(&lwp->signal);
+    rt_lwp_t new_lwp = rt_calloc(1, sizeof(struct rt_lwp));
+
+    if (new_lwp)
+    {
+        /* minimal setup of lwp object */
+        new_lwp->session = -1;
+        new_lwp->ref = 1;
+        rt_list_init(&new_lwp->wait_list);
+        rt_list_init(&new_lwp->t_grp);
+        rt_list_init(&new_lwp->timer);
+        lwp_user_object_lock_init(new_lwp);
+        rt_wqueue_init(&new_lwp->wait_queue);
+        lwp_signal_init(&new_lwp->signal);
+
+        /* lwp with pid */
+        if (flags & LWP_CREATE_FLAG_ALLOC_PID)
+        {
+            level = rt_hw_interrupt_disable();
+            pid = lwp_pid_get();
+            if (pid == 0)
+            {
+                lwp_user_object_lock_destroy(new_lwp);
+                rt_free(new_lwp);
+                new_lwp = RT_NULL;
+                LOG_E("pid slot fulled!\n");
+            }
+            else
+            {
+                new_lwp->pid = pid;
+                lwp_pid_set_lwp(pid, new_lwp);
+            }
 
-    level = rt_hw_interrupt_disable();
-    pid = lwp_pid_get();
-    if (pid == 0)
-    {
-        lwp_user_object_lock_destroy(lwp);
-        rt_free(lwp);
-        lwp = RT_NULL;
-        LOG_E("pid slot fulled!\n");
-        goto out;
+            rt_hw_interrupt_enable(level);
+        }
     }
-    lwp->pid = pid;
-    lwp_pid_set_lwp(pid, lwp);
-
-#ifdef LWP_ENABLE_ASID
-    lwp->generation = 0;
-    lwp->asid = 0;
-#endif
-
-out:
-    rt_hw_interrupt_enable(level);
-    return lwp;
+    return new_lwp;
 }
 
 void lwp_free(struct rt_lwp* lwp)

components/lwp/lwp_pid.h

@@ -17,11 +17,16 @@
 extern "C" {
 #endif
 
+#define LWP_CREATE_FLAG_NONE        0x0000
+#define LWP_CREATE_FLAG_ALLOC_PID   0x0001  /* allocate pid on lwp object create */
+
 struct rt_lwp;
 
 struct lwp_avl_struct *lwp_get_pid_ary(void);
 
-struct rt_lwp* lwp_new(void);
+/* create a lwp object */
+struct rt_lwp* lwp_create(rt_base_t flags);
+
 void lwp_free(struct rt_lwp* lwp);
 
 int lwp_ref_inc(struct rt_lwp *lwp);

components/lwp/lwp_syscall.c

@@ -2083,7 +2083,7 @@ sysret_t _sys_fork(void)
     void *user_stack = RT_NULL;
 
     /* new lwp */
-    lwp = lwp_new();
+    lwp = lwp_create(LWP_CREATE_FLAG_ALLOC_PID);
     if (!lwp)
     {
         SET_ERRNO(ENOMEM);
@@ -2685,15 +2685,13 @@ sysret_t sys_execve(const char *path, char *const argv[], char *const envp[])
     }
 
     /* alloc new lwp to operation */
-    new_lwp = (struct rt_lwp *)rt_malloc(sizeof(struct rt_lwp));
+    new_lwp = lwp_create(LWP_CREATE_FLAG_NONE);
     if (!new_lwp)
     {
         SET_ERRNO(ENOMEM);
         goto quit;
     }
-    rt_memset(new_lwp, 0, sizeof(struct rt_lwp));
-    new_lwp->ref = 1;
-    lwp_user_object_lock_init(new_lwp);
+
     ret = lwp_user_space_init(new_lwp, 0);
     if (ret != 0)
     {
@@ -2788,10 +2786,6 @@ sysret_t sys_execve(const char *path, char *const argv[], char *const envp[])
 
         rt_hw_interrupt_enable(level);
 
-        /* setup the signal, timer_list for the dummy lwp, so that is can be smoothly recycled */
-        lwp_signal_init(&new_lwp->signal);
-        rt_list_init(&new_lwp->timer);
-
         lwp_ref_dec(new_lwp);
         arch_start_umode(lwp->args,
                 lwp->text_entry,

examples/utest/testcases/mm/mm_lwp_tc.c

@@ -50,7 +50,7 @@ static void test_user_map_varea(void)
     const size_t buf_sz = ARCH_PAGE_SIZE * 4;
     struct rt_lwp *lwp;
     rt_varea_t varea;
-    lwp = lwp_new();
+    lwp = lwp_create(LWP_CREATE_FLAG_NONE);
 
     /* prepare environment */
     uassert_true(!!lwp);
@@ -74,7 +74,7 @@ static void test_user_map_varea_ext(void)
     const size_t buf_sz = ARCH_PAGE_SIZE * 4;
     struct rt_lwp *lwp;
     rt_varea_t varea;
-    lwp = lwp_new();
+    lwp = lwp_create(LWP_CREATE_FLAG_NONE);
 
     uassert_true(!!lwp);
     uassert_true(!lwp_user_space_init(lwp, 1));
@@ -104,7 +104,7 @@ static void test_user_accessible(void)
     /* Prepare Environment */
     char *test_address = (char *)(USER_STACK_VEND);
     struct rt_lwp *lwp;
-    lwp = lwp_new();
+    lwp = lwp_create(LWP_CREATE_FLAG_NONE);
     uassert_true(!!lwp);
     uassert_true(!lwp_user_space_init(lwp, 0));
 

examples/utest/testcases/mm/test_bst_adpt.h

@@ -31,7 +31,7 @@ void test_bst_adpt(void)
     rt_mem_obj_t mem_obj;
 
     /* create aspace by lwp */
-    lwp = lwp_new();
+    lwp = lwp_create(LWP_CREATE_FLAG_NONE);
     uassert_true(!!lwp);
     uassert_true(!lwp_user_space_init(lwp, 0));
     aspace = lwp->aspace;