From mboxrd@z Thu Jan 1 00:00:00 1970 From: majianpeng Subject: Re: Re: [RFC PATCH] raid5: Add R5_ReadNoMerge flag which prevent bio from merging at block layer Date: Wed, 4 Jul 2012 13:29:23 +0800 Message-ID: <201207041329205003713@gmail.com> References: <201207031423377650880@gmail.com> <20120703163810.531a000c@notabene.brown> <201207031652444687381@gmail.com>, <20120704123006.031f8b5d@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset="gb2312" Content-Transfer-Encoding: base64 Return-path: Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: linux-raid , axboe List-Id: linux-raid.ids T24gMjAxMi0wNy0wNCAxMDozMCBOZWlsQnJvd24gPG5laWxiQHN1c2UuZGU+IFdyb3RlOg0KPk9u IFR1ZSwgMyBKdWwgMjAxMiAxNjo1Mjo0OSArMDgwMCBtYWppYW5wZW5nIDxtYWppYW5wZW5nQGdt YWlsLmNvbT4gd3JvdGU6DQo+DQo+PiBPbiAyMDEyLTA3LTAzIDE0OjM4IE5laWxCcm93biA8bmVp bGJAc3VzZS5kZT4gV3JvdGU6DQo+PiA+T24gVHVlLCAzIEp1bCAyMDEyIDE0OjIzOjQxICswODAw IG1hamlhbnBlbmcgPG1hamlhbnBlbmdAZ21haWwuY29tPiB3cm90ZToNCj4+ID4NCj4+ID4+IEJl Y2F1c2UgYmlvcyB3aWxsIG1lcmdlIGF0IGJsb2NrLWxheWVyLHNvIGJpb3MtZXJyb3IgbWF5IGNh dXNlZCBieSBvdGhlcg0KPj4gPj4gYmlvIHdoaWNoIGJlIG1lcmdlZCBpbnRvIHRvIHRoZSBzYW1l IHJlcXVlc3QuDQo+PiA+PiBVc2luZyB0aGlzIGZsYWcsaXQgd2lsbCBmaW5kIGV4YWN0bHkgZXJy b3Itc2VjdG9yIGFuZCBub3QgZG8gcmVkdW5kYW50DQo+PiA+PiBvcGVyYXRpb24gbGlrZSByZS13 cml0ZSBhbmQgcmUtcmVhZC4NCj4+ID4+IA0KPj4gPj4gU2lnbmVkLW9mZi1ieTogbWFqaWFucGVu ZyA8bWFqaWFucGVuZ0BnbWFpbC5jb20+DQo+PiA+DQo+PiA+SGksDQo+PiA+IEkgdGhpbmsgdGhp cyBwYXRjaCBuZWVkcyBhIG1vcmUgZGV0YWlsZWQgZXhwbGFuYXRpb24uDQo+PiA+DQo+PiA+V2hh dCBleGFjdGx5IGlzIHRoZSBzaXR1YXRpb24gdGhhdCBjYXVzZXMgYSBwcm9ibGVtLCBhbmQgd2hh dCBleGFjdGx5IGlzIHRoZQ0KPj4gPnByb2JsZW0gdGhhdCBpdCBjYXVzZXM/DQo+PiA+DQo+PiA+ UHJldGVuZCB0aGF0IEkgZG9uJ3Qga25vdyBhbnl0aGluZyBhYm91dCB3aGF0IGhhcHBlbnMgYmVs b3cgdGhlIG1kIGxldmVsLi4NCj4+ID4NCj4+ID5UaGFua3MsDQo+PiA+TmVpbEJyb3duDQo+PiA+ DQo+PiA+DQouLi4uDQo+PiA+PiAgDQo+PiA+DQo+PiA+DQo+PiBIb3cgYWJvdXQgdGhlIGJlbG93 IGV4cGxhbmF0aW9uOg0KPj4gDQo+PiBCZWNhdXNlIGJpbyB3aWxsIGJlIG1lcmdlZCBhdCBibG9j ay1sYXllcixzbyBiaW9zLWVycm9yIG1heSBjYXVzZWQgYnkgb3RoZXINCj4+IGJpbyB3aGljaCBi ZSBtZXJnZWQgaW50byB0byB0aGUgc2FtZSByZXF1ZXN0Lg0KPj4gRm9yIGV4YW1wbGU6IGlmIGNo dW5rX2FsaWduZWRfcmVhZCBmYWlsZWQsIGl0IHdpbGwgYWRkIGJpbyB0byBzb21lIHN0aXBlLg0K Pj4gQnV0IGJlY2F1c2UgdGhlIGJpby1tZXJnZSBmdW5jdGlvbix0aG9zZSBiaW9zIGF0IG1vc3Qg YmUgbWVyZ2VkLkl0IHdpbGwgbGlrZQ0KPj4gdGhlIGNodW5rX2FsaWduZWRfcmVhZCBhbmQgcmV0 dXJlbiBlcnJvci5UaGVuIGl0IHdpbGwgcmUtd3JpdGUgYW5kIHJlLXJlYWQuDQo+PiBTdXBwb3Nl IFJBSUQ1IGNyZWF0ZWQgYnkgbiBkaXNrIGFuZCBjaHVuay1zaXplIGlzIDUxMksuDQo+PiBJZiBy ZWFkIDUxMmsgY2h1bmtfYWxpZ25lZCBhbmQgbWV0IGVycm9yKHNlY3RvciAwIGlzIG1lZGlhIGVy cm9yKSwgDQo+PiB0aGVuIGFkZCA1MTIvND0xMjggc3RpcGUuSWYgdGhvc2UgYmlvcyBtZXJnZWQg YW5kIG11c3QgYmUgZXJyb3IuVGhlIHJld3JpdGUgb3BlcmF0aW9uDQo+PiB3aWxsIHJlYWQgKG4t MSkgKiAxMjggYW5kIGNvbXB1dGVyIDEyOCBzdHJpcGUuQnV0IHVzaW5nIHRoaXMgZmxhZyx3ZSBv bmx5IGV4ZWMgb25lIHJld3JpdGUuDQo+PiBUaGlzIG9jY3VyIGluIHJlc3luYy9yZXBhaXIgc2l0 dWF0aW9uIGFuZCBjaHVuay1hbGlnbmVkLXJlYWQuDQo+PiANCj4+IE1heSBiZSB1c2luZyB0aGlz IGZsYWcsd2UgY2FuIGZpbmQgZXhhY3QgYmFkLXNlY3Rvci5Ob3QgcmVjb3JkZWQgdGhlIHdob2xl IHJlcXVlc3QgYmlvcyANCj4+IGFzIGJhZC1zZWN0b3INCj4NCj5UaGFua3MuICBUaGF0IG1ha2Ug c29tZSBzZW5zZS4NCj4NCj5JIHdvbmRlciBpZiB3ZSBjYW4ganVzdCB1c2UgUkVRX0ZVQSB0byBz dG9wIHJlcXVlc3RzIGJlaW5nIG1lcmdlZCwgcmF0aGVyDQo+dGhhbiBjcmVhdGUgYSBuZXcgZmxh Zy4gIEluIGdlbmVyYWwgd2Ugc2hvdWxkIHByb2JhYmx5IGJlIHVzaW5nIFJFUV9GVUEgaW4NCj5h bGwgdGhlIGNhc2VzIHdoZXJlIHdlIGFyZSBjaGVja2luZyBmb3IsIGFuZCB0cnlpbmcgdG8gZml4 LCByZWFkIGVycm9ycy4NCj4NCj5UaGFua3MsDQo+TmVpbEJyb3duDQo+DQo+DQpVc2luZyBSRVFf RlVBL1JFUV9GTFVTSCBjYW4gaGF2ZSBzYW1lIGVmZmVjdC4NCkJ1dCBpIHRoaW5rIFJFUV9GVUEv UkVRX0ZMVVNIIG9wZXJhdGlvbiBkbyBtb3JlIHdvcmsgZm9yIGV4YW1wbGUsIHByZV9mbHVzaC9w b3N0X3BmbHVzaCBhbmQgdGhlIGhhcmRkaXNrIHdpbGwgZG8gbW9yZQ0Kd29yay5CdXQgb3VyIHB1 cnBvc2Ugb25seSBleGVjIGJpbyBzbG9uZWx5Lg==