From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hugh Dickins Date: Sat, 28 Apr 2007 05:34:26 +0000 Subject: Re: Fw: [PATCH] ia64: race flushing icache in do_no_page path Message-Id: List-Id: References: <20070425205548.fd51b301.akpm@linux-foundation.org> <46305A8D.2080003@yahoo.com.au> <20070426173544.GA30744@ldl.fc.hp.com> <4631E49C.2030501@yahoo.com.au> <1177723863.13482.379.camel@galaxy.corp.google.com> In-Reply-To: <1177723863.13482.379.camel@galaxy.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Rohit Seth Cc: Nick Piggin , Mike Stroyan , Andrew Morton , "Luck, Tony" , linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org On Fri, 27 Apr 2007, Rohit Seth wrote: > On Fri, 2007-04-27 at 15:18 +0100, Hugh Dickins wrote: > > Right. Extra flush_icache_page routines will add cost to archs that > have non-null definition of this routine. BTW, isn't flush_icache_page > marked for deprecation? Yes, flush_icache_page is marked for deprecation: but that's hardly a reason to add another under a different name! (Not quite what you did, but...) > lazy_mmu_prot_update was added specifically for notifying change in > protection. So, in a way it is closer to update_mmu_cache (Which is for > change in mappings itself). Though for ia64 implementation, this ends > up flushing the icaches when needed. The ia64 implementation is the only one which has any use for it, and it's only interested when it's executable i.e. "lazy_mmu_prot_update" is a name concealing some overdesign. > Hopefully my reply is useful. Yes, thanks Rohit, and I'll want to read through it again later. In particular, I've now a better idea what's "lazy" about it. Hugh