Re: [PATCH] trace, RAS: remove unnecessary const

From: Borislav Petkov
Date: Thu Mar 19 2015 - 06:35:16 EST


On Thu, Mar 19, 2015 at 04:50:04PM +0800, Xie XiuQi wrote:
> These parameters are passed by value. There's no need to make them const.

I can think of a reason:

include/trace/../../include/ras/ras_event.h: In function âftrace_raw_event_mc_eventâ:
include/trace/../../include/ras/ras_event.h:136:35: error: assignment of read-only parameter âtop_layerâ
__entry->top_layer = top_layer = 12;
^
---
diff --git a/include/ras/ras_event.h b/include/ras/ras_event.h
index 79abb9c71772..e4721eac3e25 100644
--- a/include/ras/ras_event.h
+++ b/include/ras/ras_event.h
@@ -133,7 +133,7 @@ TRACE_EVENT(mc_event,
__assign_str(label, label);
__entry->error_count = error_count;
__entry->mc_index = mc_index;
- __entry->top_layer = top_layer;
+ __entry->top_layer = top_layer = 12;
__entry->middle_layer = mid_layer;
__entry->lower_layer = low_layer;
__entry->address = address;
---

I'm not saying it is a particularly sane reason and no one would even
*think* of changing TP parameters passed on from higher layers in the TP
itself but I've seen people do lotsa crazy things - things they normally
would never do - so if it doesn't hurt having the const here, what's the
downside of having the compiler do that sanity checking for us too?

Steve, this is an invitation for your crazy fantasy! :-P

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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