Re: [PATCH v7 06/16] tracepoint: use new hashtable implementation

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Oct 29, 2012 at 11:58:14AM -0700, Tejun Heo wrote:
> On Mon, Oct 29, 2012 at 02:53:19PM -0400, Mathieu Desnoyers wrote:
> > The argument about hash_init being useful to add magic values in the
> > future only works for the cases where a hash table is declared with
> > DECLARE_HASHTABLE(). It's completely pointless with DEFINE_HASHTABLE(),
> > because we could initialize any debugging variables from within
> > DEFINE_HASHTABLE().
> 
> You can do that with [0 .. HASH_SIZE - 1] initializer.

And in general, let's please try not to do optimizations which are
pointless.  Just stick to the usual semantics.  You have an abstract
data structure - invoke the initializer before using it.  Sure,
optimize it if it shows up somewhere.  And here, if we do the
initializers properly, it shouldn't cause any more actual overhead -
ie. DEFINE_HASHTABLE() will basicallly boil down to all zero
assignments and the compiler will put the whole thing in .bss anyway.

Thanks.

-- 
tejun

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>


[Index of Archives]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux]     [Linux OMAP]     [Linux MIPS]     [ECOS]     [Asterisk Internet PBX]     [Linux API]