From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH] x86: Add an explicit barrier() to clflushopt() Date: Thu, 7 Jan 2016 14:29:58 -0800 Message-ID: <568EE6E6.4000904@zytor.com> References: <1445248735-11915-1-git-send-email-chris@chris-wilson.co.uk> <20160107101652.GF652@nuc-i3427.alporthouse.com> <20160107194413.GA25144@nuc-i3427.alporthouse.com> <568ED31F.1090004@zytor.com> <20160107215401.GB25144@nuc-i3427.alporthouse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail.zytor.com (terminus.zytor.com [198.137.202.10]) by gabe.freedesktop.org (Postfix) with ESMTPS id CEF576E36A for ; Thu, 7 Jan 2016 14:30:41 -0800 (PST) In-Reply-To: <20160107215401.GB25144@nuc-i3427.alporthouse.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Chris Wilson , Andy Lutomirski , "linux-kernel@vger.kernel.org" , Ross Zwisler , "H . Peter Anvin" , Borislav Petkov , Brian Gerst , Denys Vlasenko , Linus Torvalds , Thomas Gleixner , Imre Deak , Daniel Vetter , DRI List-Id: dri-devel@lists.freedesktop.org T24gMDEvMDcvMTYgMTM6NTQsIENocmlzIFdpbHNvbiB3cm90ZToKPiAKPiBXaGlsc3QgeW91IGFy ZSBsb29raW5nIGF0IHRoaXMgYXNtLCBub3RlIHRoYXQgd2UgcmVsb2FkCj4gYm9vdF9jcHVfZGF0 YS54ODZfY2ZsdXNoX3NpemUgZXZlcnl0aW1lIGFyb3VuZCB0aGUgbG9vcC4gVGhhdCdzIGEgc21h bGwKPiBidXQgbm90aWNlYWJsZSBleHRyYSBjb3N0IChlc3BlY2lhbGx5IHdoZW4gd2UgYXJlIG9u bHkgZmx1c2hpbmcgYSBzaW5nbGUKPiBjYWNoZWxpbmUpLgo+IAoKSSBkaWQgbm90aWNlIHRoYXQ7 IEkgZG9uJ3Qga25vdyBpZiB0aGlzIGlzIGEgY29tcGlsZXIgZmFpbHVyZSB0byBkbyBhbgpvYnZp b3VzIGhvaXN0aW5nICh3aGljaCBzaG91bGQgdGhlbiBiZSBtZXJnZWQgd2l0aCB0aGUgb3RoZXIg bG9hZCkgb3IgYQpjb25zZXF1ZW5jZSBvZiB0aGUgdm9sYXRpbGUuICBJdCBtaWdodCBiZSB1c2Vm dWwgdG8gcmVwb3J0IHRoaXMgdG8gdGhlCmdjYyBidWd6aWxsYSB0byBsZXQgdGhlbSBsb29rIGF0 IGl0LgoKRWl0aGVyIHdheSwgdGhlIGRpZmYgbG9va3MgZ29vZCBhbmQgeW91IGNhbiBhZGQgbXk6 CgpBY2tlZC1ieTogSC4gUGV0ZXIgQW52aW4gPGhwYUBsaW51eC5pbnRlbC5jb20+CgpIb3dldmVy LCBJIHNlZSBhYnNvbHV0ZWx5IG5vdGhpbmcgd3Jvbmcgd2l0aCB0aGUgYXNzZW1ibHkgb3RoZXIg dGhhbgptaW5vciBvcHRpbWl6YXRpb24gcG9zc2liaWxpdGllczogc2luY2UgZ2NjIGdlbmVyYXRl cyBhbiBlYXJseS1vdXQgdGVzdAphcyB3ZWxsIGFzIGEgbGF0ZS1vdXQgdGVzdCBhbnl3YXksIHdl IGNvdWxkIGFkZCBhbiBleHBsaWNpdDoKCglpZiAocCA8IHZlbmQpCgkJcmV0dXJuOwoKYmVmb3Jl IHRoZSBmaXJzdCBtYigpIGF0IG5vIGFkZGl0aW9uYWwgY29zdCAoYXNzdW1pbmcgZ2NjIGlzIHNt YXJ0CmVub3VnaCB0byBza2lwIHRoZSBzZWNvbmQgdGVzdDsgb3RoZXJ3aXNlIHRoYXQgY2FuIGVh c2lseSBiZSBkb25lCm1hbnVhbGx5IGJ5IHJlcGxhY2luZyB0aGUgZm9yIGxvb3Agd2l0aCBhIGRv IHsgfSB3aGlsZSBsb29wLgoKSSB3b3VsZCBiZSB2ZXJ5IGludGVyZXN0ZWQgaW4ga25vd2luZyBp ZiByZXBsYWNpbmcgdGhlIGZpbmFsIGNsZmx1c2hvcHQKd2l0aCBhIGNsZmx1c2ggd291bGQgcmVz b2x2ZSB5b3VyIHByb2JsZW1zIChpbiB3aGljaCBjYXNlIHRoZSBsYXN0IG1iKCkKc2hvdWxkbid0 IGJlIG5lY2Vzc2FyeSBlaXRoZXIuKQoKU29tZXRoaW5nIGxpa2U6Cgp2b2lkIGNsZmx1c2hfY2Fj aGVfcmFuZ2Uodm9pZCAqdmFkZHIsIHVuc2lnbmVkIGludCBzaXplKQp7Cgl1bnNpZ25lZCBsb25n IGNsZmx1c2hfc2l6ZSA9IGJvb3RfY3B1X2RhdGEueDg2X2NsZmx1c2hfc2l6ZTsKCWNoYXIgKnZl bmQgPSAoY2hhciAqKXZhZGRyICsgc2l6ZTsKCWNoYXIgKnAgPSAoY2hhciAqKSgodW5zaWduZWQg bG9uZyl2YWRkciAmIH4oY2xmbHVzaF9zaXplIC0gMSk7CgoJaWYgKHAgPj0gdmVuZCkKCQlyZXR1 cm47CgoJbWIoKTsKCglmb3IgKDsgcCA8IHZlbmQgLSBjbGZsdXNoX3NpemU7IHAgKz0gY2xmbHVz aF9zaXplKQoJCWNsZmx1c2hvcHQocCk7CgoJY2xmbHVzaChwKTsJCS8qIFNlcmlhbGl6aW5nIGFu ZCB0aHVzIGEgYmFycmllciAqLwp9CgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBsaXN0cy5mcmVl ZGVza3RvcC5vcmcKaHR0cDovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZv L2RyaS1kZXZlbAo=