cpu: Use QTAILQ for CPU list

Introduce CPU_FOREACH(), CPU_FOREACH_SAFE() and CPU_NEXT() shorthand
macros.

Signed-off-by: Andreas Färber <afaerber@suse.de>

3 files changed, 10 insertions, 19 deletions

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 7ce2eab1bb..72d92707c6 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -2668,7 +2668,7 @@ static int fill_note_info(struct elf_note_info *info,
 
     /* read and fill status of all threads */
     cpu_list_lock();
-    for (cpu = first_cpu; cpu != NULL; cpu = cpu->next_cpu) {
+    CPU_FOREACH(cpu) {
         if (cpu == thread_cpu) {
             continue;
         }
diff --git a/linux-user/main.c b/linux-user/main.c
index 03859bcc23..5c2f7b26b4 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -117,10 +117,14 @@ void fork_end(int child)
 {
     mmap_fork_end(child);
     if (child) {
+        CPUState *cpu, *next_cpu;
         /* Child processes created by fork() only have a single thread.
            Discard information about the parent threads.  */
-        first_cpu = thread_cpu;
-        first_cpu->next_cpu = NULL;
+        CPU_FOREACH_SAFE(cpu, next_cpu) {
+            if (cpu != thread_cpu) {
+                QTAILQ_REMOVE(&cpus, thread_cpu, node);
+            }
+        }
         pending_cpus = 0;
         pthread_mutex_init(&exclusive_lock, NULL);
         pthread_mutex_init(&cpu_list_mutex, NULL);
@@ -154,7 +158,7 @@ static inline void start_exclusive(void)
 
     pending_cpus = 1;
     /* Make all other cpus stop executing.  */
-    for (other_cpu = first_cpu; other_cpu; other_cpu = other_cpu->next_cpu) {
+    CPU_FOREACH(other_cpu) {
         if (other_cpu->running) {
             pending_cpus++;
             cpu_exit(other_cpu);
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index f986548c2d..ecead512a0 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -5113,25 +5113,12 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
            Do thread termination if we have more then one thread.  */
         /* FIXME: This probably breaks if a signal arrives.  We should probably
            be disabling signals.  */
-        if (first_cpu->next_cpu) {
+        if (CPU_NEXT(first_cpu)) {
             TaskState *ts;
-            CPUState **lastp;
-            CPUState *p;
 
             cpu_list_lock();
-            lastp = &first_cpu;
-            p = first_cpu;
-            while (p && p != cpu) {
-                lastp = &p->next_cpu;
-                p = p->next_cpu;
-            }
-            /* If we didn't find the CPU for this thread then something is
-               horribly wrong.  */
-            if (!p) {
-                abort();
-            }
             /* Remove the CPU from the list.  */
-            *lastp = p->next_cpu;
+            QTAILQ_REMOVE(&cpus, cpu, node);
             cpu_list_unlock();
             ts = ((CPUArchState *)cpu_env)->opaque;
             if (ts->child_tidptr) {