On Thu, Nov 05, 2015 at 04:09:18PM +0100, Adrien Mazarguil wrote:
>
> I won't argue against this as it's obviously more complex than the original
> method, however note that users of the RTE_PMD_DEBUG_TRACE() macro do not
> have to modify their code. They shouldn't care about the implementation.
>
> Also note that we can do much cleaner code if we drop the all macros
> implementation using a (much easier to debug) static inline function,
> only perhaps with a wrapper macro that provides __LINE__, __func__ and
> __FILE__ as arguments. Nontrival code shouldn't be done in macros anyway.
>
Getting something working with __FILE__ and probably __LINE__ would be easy
enough
with a helper macro, but __func__ is not so easy as it's not a preprocessor
symbol
[since the pre-processor has no idea what function you are in].
However, using func, here is the best I've come up with so far. It's not that
pretty, but it's probably easier to work with than the macro version.
#ifdef RTE_LIBRTE_ETHDEV_DEBUG
-#define RTE_PMD_DEBUG_TRACE(fmt, args...) \
- RTE_LOG(ERR, PMD, "%s: " fmt, __func__, ## args)
+#define RTE_PMD_DEBUG_TRACE(...) \
+ rte_pmd_debug_trace(__func__, __VA_ARGS__)
+
+static inline void
+rte_pmd_debug_trace(const char *func_name, const char *fmt, ...)
+{
+ static __thread char buffer[128];
+ char *out_buf = buffer;
+ unsigned count;
+ va_list ap;
+
+ count = snprintf(buffer, sizeof(buffer), "%s: %s", func_name, fmt);
+ if (count >= sizeof(buffer)) { // truncated output
+ char *new_buf = malloc(count + 1);
+ if (new_buf == NULL) // no memory, just print 128 chars
+ goto print_buffer;
+ snprintf(new_buf, count + 1, "%s: %s", func_name, fmt);
+ va_start(ap, fmt);
+ rte_vlog(RTE_LOG_ERR, RTE_LOGTYPE_PMD, buffer, ap);
+ va_end(ap);
+ free(new_buf);
+ return;
+ }
+
+print_buffer:
+ va_start(ap, fmt);
+ rte_vlog(RTE_LOG_ERR, RTE_LOGTYPE_PMD, out_buf, ap);
+ va_end(ap);
+}
#else
#define RTE_PMD_DEBUG_TRACE(fmt, args...)
#endif
Comments or improvements?
/Bruce
