Hi Namhyung,
thanks again for taking your time to review.

On Tue, 2021-08-24 at 12:27 -0700, Namhyung Kim wrote:

Hi Riccardo,

On Fri, Aug 20, 2021 at 3:54 AM Riccardo Mancini [off-list ref] wrote:

quoted

+/**
+ * workqueue_strerror - print message regarding lastest error in @wq
+ *
+ * Buffer size should be at least WORKQUEUE_STRERR_BUFSIZE bytes.
+ */
+int workqueue_strerror(struct workqueue_struct *wq, int err, char *buf,
size_t size)
+{
+       int ret;
+       char sbuf[THREADPOOL_STRERR_BUFSIZE], *emsg;
+       const char *errno_str;
+
+       errno_str = workqueue_errno_str[-err-WORKQUEUE_ERROR__OFFSET];

It seems easy to crash with an invalid err argument.

Yup, I should add a check in the next version.

quoted

+
+       switch (err) {
+       case -WORKQUEUE_ERROR__POOLNEW:
+       case -WORKQUEUE_ERROR__POOLEXE:
+       case -WORKQUEUE_ERROR__POOLSTOP:
+       case -WORKQUEUE_ERROR__POOLSTARTTHREAD:
+               if (IS_ERR_OR_NULL(wq))
+                       return scnprintf(buf, size, "%s: unknown.\n",
+                               errno_str);
+
+               ret = threadpool__strerror(wq->pool, wq->pool_errno, sbuf,
sizeof(sbuf));
+               if (ret < 0)
+                       return ret;
+               return scnprintf(buf, size, "%s: %s.\n", errno_str, sbuf);
+       case -WORKQUEUE_ERROR__WRITEPIPE:
+       case -WORKQUEUE_ERROR__READPIPE:
+               emsg = str_error_r(errno, sbuf, sizeof(sbuf));

This means the errno should be kept before calling this, right?

Yeah, I should make sure to preserve it, I think it's done this way in some
other functions.
Otherwise, I can save it in a struct attribute, which is maybe simpler.

quoted

+               return scnprintf(buf, size, "%s: %s.\n", errno_str, emsg);
+       case -WORKQUEUE_ERROR__INVALIDMSG:
+               return scnprintf(buf, size, "%s.\n", errno_str);
+       default:
+               emsg = str_error_r(err, sbuf, sizeof(sbuf));
+               return scnprintf(buf, size, "Error: %s", emsg);

Newline at the end?

Forgot it, thanks!

Riccardo

Thanks,
Namhyung

quoted

+       }
+}
+