hwthread: Restore current_threadid in hwthread_update_threads

When OpenOCD receives a step-execution command from GDB and the target
is configured as rtos=hwthread, OpenOCD reconstructs the thread-info.
However, OpenOCD does not restore the thread id which is currently
selected by GDB. Due to this issue, OpenOCD sends the information of
wrong thread to GDB after the step execution.
This commit fixes the above issue by adding a code to save/restore the
thread id selected by GDB.

Signed-off-by: Koudai Iwahori <koudai@google.com>
Change-Id: I761a1141c04d48f1290e4f09baa7c7024f86f36a
Reviewed-on: https://review.openocd.org/c/openocd/+/7358
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>

diff --git a/src/rtos/hwthread.c b/src/rtos/hwthread.c
index 1540168c30abd830406e8a6481d6132aee1e3cd4..03c4d8550397d151f7ea9e44a8fc65e13e291420 100644 (file)
--- a/src/rtos/hwthread.c
+++ b/src/rtos/hwthread.c
@@ -82,6 +82,7 @@ static int hwthread_update_threads(struct rtos *rtos)
        struct target_list *head;
        struct target *target;
        int64_t current_thread = 0;
+       int64_t current_threadid = rtos->current_threadid; /* thread selected by GDB */
        enum target_debug_reason current_reason = DBG_REASON_UNDEFINED;
 
        if (!rtos)
@@ -105,6 +106,15 @@ static int hwthread_update_threads(struct rtos *rtos)
        } else
                thread_list_size = 1;
 
+       /* restore the threadid which is currently selected by GDB
+        * because rtos_free_threadlist() wipes out it
+        * (GDB thread id is 1-based indexing) */
+       if (current_threadid <= thread_list_size)
+               rtos->current_threadid = current_threadid;
+       else
+               LOG_WARNING("SMP node change, disconnect GDB from core/thread %" PRId64,
+                           current_threadid);
+
        /* create space for new thread details */
        rtos->thread_details = malloc(sizeof(struct thread_detail) * thread_list_size);