Re: [dpdk-dev] [PATCH v9 06/10] eal: add thread lifetime management

On Wed, Jun 09, 2021 at 02:04:09AM +0300, Dmitry Kozlyuk wrote:

2021-06-04 16:44 (UTC-0700), Narcisa Ana Maria Vasile:
[...]

quoted

diff --git a/lib/eal/include/rte_thread.h b/lib/eal/include/rte_thread.h
index 5c54cd9d67..1d481b9ad5 100644
--- a/lib/eal/include/rte_thread.h
+++ b/lib/eal/include/rte_thread.h
+__rte_experimental
+int rte_thread_create(rte_thread_t *thread_id,
+		      const rte_thread_attr_t *thread_attr,
+		      void *(*thread_func)(void *), void *args);

1. Thread function prototype is used at least in 4 places,
maybe give it a name, like `rte_thread_func`?

2. We can't easily support it's `void*` return type on Windows,
because it doesn't fit in DWORD. In `rte_thread_join` below you use `int`.
All `pthread_join` usages in DPDK ignore return value, but I'd rather keep it.
Do you think it's OK to stick to `int`?

Thank you, I agree that we should keep it. I've changed it to unsigned long
to fit with Windows's DWORD as well.

[...]

quoted

+/**
+ * Terminates a thread.
+ *
+ * @param thread_id
+ *    The id of the thread to be cancelled.
+ *
+ * @return
+ *   On success, return 0.
+ *   On failure, return a positive errno-style error number.
+ */
+__rte_experimental
+int rte_thread_cancel(rte_thread_t thread_id);

What do you think of making this function internal for now?
We don't want applications to rely on this prototype.
To hide it from Doxygen, `/*` comment or #ifndef __DOXYGEN__ can be used.
It is worth noting in commit message
that it's not implemented for Windows and why.

 Thank you, I've removed it for now.

quoted

+
+	HANDLE thread_handle = NULL;
+	GROUP_AFFINITY thread_affinity;
+	struct thread_routine_ctx *ctx = NULL;
+
+	ctx = calloc(1, sizeof(*ctx));

Why use `calloc()` for a scalar?

ctx is pointer to struct that holds the thread function pointer and its arguments.
Did I misunderstand what you meant?