Re: [PATCH V2 02/11] cxl/mem: Implement Get Event Records command

Steven Rostedt
2022-12-02T04:41:09Z

On Thu, 1 Dec 2022 16:09:17 -0800
Ira Weiny <ira.weiny@intel.com> wrote:

> Dropping that into cxlmem.h does not compile. I've given it another go but
> because I use cxl_event_log_type_str() in a file where trace points are used
> CREATE_TRACE_POINTS is defined and I get the following error.
>
> || drivers/cxl/core/mbox.c: In function ‘cxl_mem_get_records_log’:
> drivers/cxl/cxlmem.h|386 col 7| error: implicit declaration of function ‘__print_symbolic’; did you mean ‘sprint_symbol’? [-Werror=implicit-function-declaration]
> || 386 | __print_symbolic(type, \
> || | ^~~~~~~~~~~~~~~~
>
> I got it to work with the patch below on top of this one.[3] But it is kind of
> ugly. The only way I could get __print_symbolic() to be defined was to
> redefine it in mbox.c.[1] Then throw it in it's own header as in [3]

I played around a bit, and with the below patch, you can just have:

#define cxl_event_log_type_str(type) \
__print_symbolic(type, \
{ CXL_EVENT_TYPE_INFO, "Informational" }, \
{ CXL_EVENT_TYPE_WARN, "Warning" }, \
{ CXL_EVENT_TYPE_FAIL, "Failure" }, \
{ CXL_EVENT_TYPE_FATAL, "Fatal" })

And everything else should "just work" :-)

I can work on a more formal patch if this works for you. And thinking about
this, perhaps we could add this throughout the kernel!

-- Steve

diff --git a/include/trace/define_trace.h b/include/trace/define_trace.h
index 00723935dcc7..ee41057674a2 100644
--- a/include/trace/define_trace.h
+++ b/include/trace/define_trace.h
@@ -132,4 +132,25 @@
/* We may be processing more files */
#define CREATE_TRACE_POINTS

+#ifndef __DEFINE_PRINT_SYMBOLIC_STR
+#define __DEFINE_PRINT_SYMBOLIC_STR
+static inline const char *
+__print_symbolic_str(int type, struct trace_print_flags *symbols)
+{
+ for (; symbols->name != NULL; symbols++) {
+ if (type == symbols->mask)
+ return symbols->name;
+ }
+ return "<invalid>";
+}
+#endif
+
+#undef __print_symbolic
+#define __print_symbolic(value, symbol_array...) \
+ ({ \
+ static const struct trace_print_flags symbols[] = \
+ { symbol_array, { -1, NULL }}; \
+ __print_symbolic_str(value, symbols); \
+ })
+
#endif /* CREATE_TRACE_POINTS */
diff --git a/include/trace/stages/stage7_class_define.h b/include/trace/stages/stage7_class_define.h
index 8a7ec24c246d..6fe83397f65d 100644
--- a/include/trace/stages/stage7_class_define.h
+++ b/include/trace/stages/stage7_class_define.h
@@ -6,7 +6,6 @@
#define __entry REC

#undef __print_flags
-#undef __print_symbolic
#undef __print_hex
#undef __print_hex_str
#undef __get_dynamic_array