From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f181.google.com (mail-io0-f181.google.com [209.85.223.181]) by kanga.kvack.org (Postfix) with ESMTP id 6C01D828ED for ; Fri, 8 Jan 2016 18:31:04 -0500 (EST) Received: by mail-io0-f181.google.com with SMTP id 77so270537687ioc.2 for ; Fri, 08 Jan 2016 15:31:04 -0800 (PST) Received: from mail-ig0-x230.google.com (mail-ig0-x230.google.com. [2607:f8b0:4001:c05::230]) by mx.google.com with ESMTPS id z9si17753309ioi.192.2016.01.08.15.31.03 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 08 Jan 2016 15:31:03 -0800 (PST) Received: by mail-ig0-x230.google.com with SMTP id z14so67825059igp.1 for ; Fri, 08 Jan 2016 15:31:03 -0800 (PST) MIME-Version: 1.0 In-Reply-To: References: Date: Fri, 8 Jan 2016 15:31:03 -0800 Message-ID: Subject: Re: [RFC 00/13] x86/mm: PCID and INVPCID From: Linus Torvalds Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Andy Lutomirski Cc: the arch/x86 maintainers , Linux Kernel Mailing List , Borislav Petkov , Brian Gerst , Dave Hansen , Oleg Nesterov , "linux-mm@kvack.org" On Fri, Jan 8, 2016 at 3:15 PM, Andy Lutomirski wrote: > > Please play around and suggest (and run?) good benchmarks. It seems > to save around 100ns on cross-process context switches for me. Interesting. There was reportedly (I never saw it) a test-patch to use pcids inside of Intel a couple of years ago, and it never got outside because it didn't make a difference. Either things have changed (newer hardware with more pcids perhaps?) or you did a better job at it. Linus -- 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