Return-Path: Received: from us-smtp-delivery-194.mimecast.com ([63.128.21.194]:33816 "EHLO us-smtp-delivery-194.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751376AbdHKFzw (ORCPT ); Fri, 11 Aug 2017 01:55:52 -0400 From: Trond Myklebust To: "viro@zeniv.linux.org.uk" , "jlayton@redhat.com" , "neilb@suse.com" CC: "linux-kernel@vger.kernel.org" , "mkoutny@suse.com" , "linux-nfs@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" Subject: Re: Do we really need d_weak_revalidate??? Date: Fri, 11 Aug 2017 05:55:46 +0000 Message-ID: <1502430944.3822.1.camel@primarydata.com> References: <87bmnmrai9.fsf@notabene.neil.brown.name> In-Reply-To: <87bmnmrai9.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: T24gRnJpLCAyMDE3LTA4LTExIGF0IDE0OjMxICsxMDAwLCBOZWlsQnJvd24gd3JvdGU6DQo+IEZ1 bm55IHN0b3J5LiAgNC41IHllYXJzIGFnbyB3ZSBkaXNjYXJkZWQgdGhlIEZTX1JFVkFMX0RPVCBz dXBlcmJsb2NrDQo+IGZsYWcgYW5kIGludHJvZHVjZWQgdGhlIGRfd2Vha19yZXZhbGlkYXRlIGRl bnRyeSBvcGVyYXRpb24gaW5zdGVhZC4NCj4gV2UgZHVseSByZW1vdmVkIHRoZSBmbGFnIGZyb20g TkZTIHN1cGVyYmxvY2tzIGFuZCBORlN2NCBzdXBlcmJsb2NrcywNCj4gYW5kIGFkZGVkIHRoZSBu ZXcgZGVudHJ5IG9wZXJhdGlvbiB0byBORlMgZGVudHJpZXMgLi4uLiBidXQgbm90IHRvDQo+IE5G U3Y0DQo+IGRlbnRyaWVzLg0KPiANCj4gQW5kIG5vYm9keSBub3RpY2VkLg0KPiANCj4gVW50aWwg dG9kYXkuDQo+IA0KPiBBIGN1c3RvbWVyIHJlcG9ydHMgYSBzaXR1YXRpb24gd2hlcmUgbW91bnQo Li4uLixNU19SRU1PVU5ULC4uKSBvbiBhbg0KPiBORlMNCj4gZmlsZXN5c3RlbSBoYW5ncyBiZWNh dXNlIHRoZSBuZXR3b3JrIGhhcyBiZWVuIGRlY29uZmlndXJlZC4gIFRoaXMNCj4gbWFrZXMNCj4g cGVyZmVjdCBzZW5zZSBhbmQgSSBzdWdnZXN0ZWQgYSBjb2RlIGNoYW5nZSB0byBmaXggdGhlIHBy b2JsZW0uDQo+IEhvd2V2ZXIgd2hlbiBhIGNvbGxlYWd1ZSB3YXMgdHJ5aW5nIHRvIHJlcHJvZHVj ZSB0aGUgcHJvYmxlbSB0bw0KPiB2YWxpZGF0ZQ0KPiB0aGUgZml4LCBoZSBjb3VsZG4ndC4gIFRo ZW4gbm9yIGNvdWxkIEkuDQo+IA0KPiBUaGUgcHJvYmxlbSBpcyB0cml2aWFsbHkgcmVwcm9kdWNp YmxlIHdpdGggTkZTdjMsIGFuZCBub3QgYXQgYWxsIHdpdGgNCj4gTkZTdjQuICBUaGUgcmVhc29u IGlzIHRoZSBtaXNzaW5nIGRfd2Vha19yZXZhbGlkYXRlLg0KPiANCj4gV2UgY291bGQgc2ltcGx5 IGFkZCBkX3dlYWtfcmV2YWxpZGF0ZSBmb3IgTkZTdjQsIGJ1dCBnaXZlbiB0aGF0IGl0DQo+IGhh cyBiZWVuIG1pc3NpbmcgZm9yIDQuNSB5ZWFycywgYW5kIHRoZSBvbmx5IHRpbWUgYW55b25lIG5v dGljZWQgd2FzDQo+IHdoZW4gdGhlIG9tbWlzc2lvbiByZXN1bHRlZCBpbiBhIGJldHRlciB1c2Vy IGV4cGVyaWVuY2UsIEkgZG8gd29uZGVyDQo+IGlmDQo+IHdlIG5lZWQgdG8uICBDYW4gd2UganVz dCBkaXNjYXJkIGRfd2Vha19yZXZhbGlkYXRlPyAgV2hhdCBwdXJwb3NlDQo+IGRvZXMNCj4gaXQg c2VydmU/ICBJIGNvdWxkbid0IGZpbmQgb25lLg0KPiANCj4gVGhhbmtzLA0KPiBOZWlsQnJvd24N Cj4gDQo+IEZvciByZWZlcmVuY2UsIHNlZQ0KPiBDb21taXQ6IGVjZjNkMWYxYWE3NCAoInZmczog a2lsbCBGU19SRVZBTF9ET1QgYnkgYWRkaW5nIGENCj4gZF93ZWFrX3JldmFsaWRhdGUgZGVudHJ5 IG9wIikNCj4gDQo+IA0KPiANCj4gVG8gcmVwcm9kdWNlIHRoZSBwcm9ibGVtIGF0IGhvbWUsIG9u IGEgc3lzdGVtIHRoYXQgdXNlcyBzeXN0ZW1kOg0KPiAxLyBwbGFjZSAob3IgZmluZCkgYSBmaWxl c3lzdGVtIGltYWdlIGluIGEgZmlsZSBvbiBhbiBORlMgZmlsZXN5c3RlbS4NCj4gMi8gbW91bnQg dGhlIG5mcyBmaWxlc3lzdGVtIHdpdGggIm5vYWMiIC0gY2hvb3NlIHYzIG9yIHY0DQo+IDMvIGxv b3AtbW91bnQgdGhlIGZpbGVzeXN0ZW0gaW1hZ2UgcmVhZC1vbmx5IHNvbWV3aGVyZQ0KPiA0LyBy ZWJvb3QNCj4gDQo+IElmIHlvdSBjaG9vc2UgdjQsIHRoZSByZWJvb3Qgd2lsbCBzdWNjZWVkLCBw b3NzaWJseSBhZnRlciBhIDkwc2Vjb25kDQo+IHRpbWVvdXQuDQo+IElmIHlvdSBjaG9vc2UgdjMs IHRoZSByZWJvb3Qgd2lsbCBoYW5nIGluZGVmaW5pdGVseSBpbiBzeXN0ZW1kLQ0KPiBzaHV0ZG93 biB3aGlsZQ0KPiByZW1vdW50aW5nIHRoZSBuZnMgZmlsZXN5c3RlbSByZWFkLW9ubHkuDQo+IA0K PiBJZiB5b3UgZG9uJ3QgdXNlICJub2FjIiBpdCBjYW4gc3RpbGwgaGFuZywgYnV0IG9ubHkgaWYg c29tZXRoaW5nDQo+IHNsb3dzDQo+IGRvd24gdGhlIHJlYm9vdCBlbm91Z2ggdGhhdCBhdHRyaWJ1 dGVzIGhhdmUgdGltZWQgb3V0IGJ5IHRoZSB0aW1lDQo+IHRoYXQNCj4gc3lzdGVtZC1zaHV0ZG93 biBydW5zLiAgVGhpcyBoYXBwZW5zIGZvciBvdXIgY3VzdG9tZXIuDQo+IA0KPiBJZiB0aGUgbG9v cC1tb3VudGVkIGZpbGVzeXN0ZW0gaXMgbm90IHJlYWQtb25seSwgeW91IGdldCBvdGhlcg0KPiBw cm9ibGVtcy4NCj4gDQo+IFdlIHJlYWxseSB3YW50IHN5c3RlbWQgdG8gZmlndXJlIG91dCB0aGF0 IHRoZSBsb29wLW1vdW50IG5lZWRzIHRvIGJlDQo+IHVubW91bnRlZCBmaXJzdC4gIEkgaGF2ZSBp ZGVhcyBjb25jZXJuaW5nIHRoYXQsIGJ1dCBpdCBpcyBtZXNzeS4gIEJ1dA0KPiB0aGF0IGlzbid0 IHRoZSBvbmx5IGJ1ZyBoZXJlLg0KDQpUaGUgbWFpbiBwdXJwb3NlIG9mIGRfd2Vha19yZXZhbGlk YXRlKCkgd2FzIHRvIGNhdGNoIHRoZSBpc3N1ZXMgdGhhdA0KYXJpc2Ugd2hlbiBzb21lb25lIGNo YW5nZXMgdGhlIGNvbnRlbnRzIG9mIHRoZSBjdXJyZW50IHdvcmtpbmcNCmRpcmVjdG9yeSBvciBp dHMgcGFyZW50IG9uIHRoZSBzZXJ2ZXIuIFNpbmNlICcuJyBhbmQgJy4uJyBhcmUgdHJlYXRlZA0K c3BlY2lhbGx5IGluIHRoZSBsb29rdXAgY29kZSwgdGhleSB3b3VsZCBub3QgYmUgcmV2YWxpZGF0 ZWQgd2l0aG91dA0Kc3BlY2lhbCB0cmVhdG1lbnQuIFRoYXQgbGVhZHMgdG8gaXNzdWVzIHdoZW4g bG9va2luZyB1cCBmaWxlcyBhcw0KLi88ZmlsZW5hbWU+IG9yIC4uLzxmaWxlbmFtZT4sIHNpbmNl IHRoZSBjbGllbnQgd29uJ3QgZGV0ZWN0IHRoYXQgaXRzDQpkY2FjaGUgaXMgc3RhbGUgdW50aWwg aXQgdHJpZXMgdG8gdXNlIHRoZSBjYWNoZWQgZGVudHJ5K2lub2RlLg0KDQpUaGUgb25lIHRoaW5n IHRoYXQgaGFzIGNoYW5nZWQgc2luY2UgaXRzIGludHJvZHVjdGlvbiBpcywgSSBiZWxpZXZlLA0K dGhlIEVTVEFMRSBoYW5kbGluZyBpbiB0aGUgVkZTIGxheWVyLiBUaGF0IG1pZ2h0IGZpeCBhIGxv dCBvZiB0aGUNCmRjYWNoZSBsb29rdXAgYnVncyB0aGF0IHdlcmUgcHJldmlvdXNseSBoYW5kbGVk IGJ5IGRfd2Vha19yZXZhbGlkYXRlKCkuDQpJIGhhdmVuJ3QgZG9uZSBhbiBhdWRpdCB0byBmaWd1 cmUgb3V0IGlmIGl0IGFjdHVhbGx5IGNhbiBoYW5kbGUgYWxsIG9mDQp0aGVtLg0KDQotLSANClRy b25kIE15a2xlYnVzdA0KTGludXggTkZTIGNsaWVudCBtYWludGFpbmVyLCBQcmltYXJ5RGF0YQ0K dHJvbmQubXlrbGVidXN0QHByaW1hcnlkYXRhLmNvbQ0K