[cocci] Searching for questionable call pairs (with SmPL)?

[Markus Elfring <Markus.Elfring@web.de>]

Hello,

I noticed another contribution.

I got into the mood to construct another script for the semantic patch language.


// See also:
// [PATCH v4] ALSA: usb-audio: qcom: Adjust mutex unlock order
// https://lore.kernel.org/linux-sound/20250721114554.1666104-1-karanja99erick@gmail.com/
@display@
expression x, y;
@@
*mutex_lock(x);
 ...
*mutex_lock(y);
 <+...
*mutex_unlock(x);
 ...
*mutex_unlock(y);
 ...+>


Questionable test result (by the software combination “Coccinelle 1.3.0” for example):
Markus_Elfring@Sonne:…/Projekte/Linux/next-analyses> git checkout next-20250722 && time /usr/bin/spatch --no-loops …/Projekte/Coccinelle/janitor/show_questionable_unlock_call_order.cocci sound/usb/qcom/qc_audio_offload.c
…
@@ -1580,7 +1576,6 @@ static void handle_uaudio_stream_req(str
                goto response;
        }
 
-       mutex_lock(&chip->mutex);
        if (req_msg->enable) {
                if (info_idx < 0 || chip->system_suspend || subs->opened) {
                        ret = -EBUSY;
@@ -1613,9 +1608,7 @@ static void handle_uaudio_stream_req(str
                        ret = prepare_qmi_response(subs, req_msg, &resp,
                                                   info_idx);
                if (ret < 0) {
-                       mutex_lock(&chip->mutex);
                        subs->opened = 0;
-                       mutex_unlock(&chip->mutex);
                }
        } else {
                info = &uadev[pcm_card_num].info[info_idx];
@@ -1646,9 +1639,7 @@ static void handle_uaudio_stream_req(str
                }
 
                disable_audio_stream(subs);
-               mutex_lock(&chip->mutex);
                subs->opened = 0;
-               mutex_unlock(&chip->mutex);
        }
 
 response:
@@ -1662,7 +1653,6 @@ response:
                if (atomic_read(&uadev[pcm_card_num].in_use))
                        kref_put(&uadev[pcm_card_num].kref,
                                 uaudio_dev_release);
-               mutex_unlock(&chip->mutex);
        }
        mutex_unlock(&qdev_mutex);
 
…
real    0m0,501s
user    0m0,460s
sys     0m0,035s


Now I wonder how these diff hunks fit to my source code search approach
for finding call pairs of known functions (or macros).
Will another clarification become more interesting?

Regards,
Markus