On 9/25/26 6:17 PM, Patrice CHOTARD wrote:


On 9/17/26 16:26, Marek Vasut wrote:
On 9/17/26 10:58 AM, Patrice Chotard wrote:
On STM32MP157C-DK2, when aborting the command "ums" using CTRL-C
it may take a while to get the control back on the console,
sometimes around 1 second.

By removing the if (k == 10) test, it increases the CTRL+C responsiveness.

Tested on STM32MP157C-DK board.
I still have two questions:

First, do you have actual timing figures here -- how long did it take from one 
ctrl_c() invocation to the next ctrl_c() invocation. Use e.g. get_timer_us() to 
time this.

Second, does this increase in break condition checking impact throughput of the 
UMS ?

Hi Marek

Time between 2 ctrl_c() invocation is around 100us, way to fast in my opinion.

UMS throughput is slightly impacted :
before : 7.35 MB/s
after : 7.17 MB/s

A better balance can be obtained with the following update :

static int sleep_thread(struct fsg_common *common)
  {
        int     rc = 0;
-       int i = 0, k = 0;
+       int i = 0;
/* Wait until a signal arrives or we are woken up */
        for (;;) {
                if (common->thread_wakeup_needed)
                        break;
if (++i == 20000) {
                        busy_indicator();
                        i = 0;
-                       k++;
-               }
- if (k == 10) {
                        /* Handle START-STOP UNIT */
                        if (common->eject)
                                return -EPIPE;
/* Handle CTRL+C */
                        if (ctrlc())
                                return -EPIPE;
/* Check cable connection */
                        if (!g_dnl_board_usb_cable_connected())
                                return -EIO;
-
-                       k = 0;

If k is not reset here, then the ++i==20000 above triggers only once ?

                }
                schedule();
                dm_usb_gadget_handle_interrupts(udcdev);
        }

Time between 2 ctrl_c() invocation is around 28ms.
UMS throughput is not impacted (still around 7.35 MB/s)

I will send a v2.

Patrice


--
Best regards,
Marek Vasut

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