From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx181.postini.com [74.125.245.181]) by kanga.kvack.org (Postfix) with SMTP id 7BA226B005D for ; Thu, 2 Aug 2012 17:46:35 -0400 (EDT) Received: by bkcjc3 with SMTP id jc3so5028bkc.14 for ; Thu, 02 Aug 2012 14:46:33 -0700 (PDT) Message-ID: <501AF555.3050004@gmail.com> Date: Thu, 02 Aug 2012 23:47:01 +0200 From: Sasha Levin MIME-Version: 1.0 Subject: Re: [RFC 1/4] hashtable: introduce a small and naive hashtable References: <5019B0B4.1090102@gmail.com> <20120801224556.GF15477@google.com> <501A4FC1.8040907@gmail.com> <20120802103244.GA23318@leaf> <501A633B.3010509@gmail.com> <501A7AD3.7000008@gmail.com> <20120802161556.GA25572@leaf> <501AAF47.3090708@gmail.com> <20120802174457.GA6251@jtriplet-mobl1> <501ABEE2.10007@gmail.com> <20120802204157.GB7916@jtriplet-mobl1> In-Reply-To: <20120802204157.GB7916@jtriplet-mobl1> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Josh Triplett Cc: Tejun Heo , torvalds@linux-foundation.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, paul.gortmaker@windriver.com On 08/02/2012 10:41 PM, Josh Triplett wrote: > On Thu, Aug 02, 2012 at 07:54:42PM +0200, Sasha Levin wrote: >> /* I've "preprocessed" the DEFINE macro below */ >> union { >> struct hash_table table; >> struct { >> size_t bits; >> struct hlist_head buckets[32]; >> } >> } my_hashtable; > > That expansion doesn't match the macros. Using the most recent > definitions of DEFINE_HASHTABLE and DEFINE_STATIC_HASHTABLE from above, > the definition would look something like this: > > static union { > struct hash_table my_hashtable; > struct { > size_t bits; > struct hlist_head buckets[1 << 5]; > } __my_hashtable; > } = { .my_hashtable.bits = 5 }; It's different because I don't think you can do what you did above with global variables. You won't be defining any instances of that anonymous struct, so my_hashtable won't exist anywhere. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org