From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [PATCH 2/2] xen: sched: we never get into context_switch() with prev==next Date: Fri, 26 Apr 2019 17:26:25 +0100 Message-ID: <04305f60-785d-cd21-1de4-9772f5bda198@citrix.com> References: <155577364571.25746.11988517450711182732.stgit@wayrath> <155577388740.25746.3780283868034526234.stgit@wayrath> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from us1-rack-dfw2.inumbo.com ([104.130.134.6]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hK3gE-0006T9-CC for xen-devel@lists.xenproject.org; Fri, 26 Apr 2019 16:26:30 +0000 In-Reply-To: Content-Language: en-GB List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" To: Julien Grall , Dario Faggioli , Andrii Anisov , xen-devel@lists.xenproject.org Cc: Juergen Gross , Stefano Stabellini , Wei Liu , George Dunlap , Jan Beulich , =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= List-Id: xen-devel@lists.xenproject.org T24gMjYvMDQvMjAxOSAxNzoyMiwgSnVsaWVuIEdyYWxsIHdyb3RlOgo+IEhpIERhcmlvLAo+Cj4g T24gMjYvMDQvMjAxOSAxNjoxMywgRGFyaW8gRmFnZ2lvbGkgd3JvdGU6Cj4+IE9uIFR1ZSwgMjAx OS0wNC0yMyBhdCAxMjoxMyArMDMwMCwgQW5kcmlpIEFuaXNvdiB3cm90ZToKPj4+IEhlbGxvIERh cmlvLAo+Pj4KPj4+IE9uIDIwLjA0LjE5IDE4OjI0LCBEYXJpbyBGYWdnaW9saSB3cm90ZToKPj4+ PiBJbiBzY2hlZHVsZSgpLCBpZiB3ZSBwaWNrLCBhcyB0aGUgbmV4dCB2Y3B1IHRvIHJ1biAobmV4 dCkgdGhlIHNhbWUKPj4+PiBvbmUKPj4+PiB0aGF0IGlzIHJ1bm5pbmcgYWxyZWFkeSAocHJldiks IHdlIG5ldmVyIGdldCB0byBjYWxsCj4+Pj4gY29udGV4dF9zd2l0Y2goKS4KPj4+Cj4+PiBBbmQg d2hhdCBhYm91dCBgaWYgKCBwcmV2ICE9IGN1cnJlbnQgKWAgaW4KPj4+IGFybS9kb21haW4uYzpz Y2hlZHVsZV90YWlsKCkgPwo+Pj4KPj4gWW91J3JlIHN1Z2dlc3RpbmcgdGhhdCdzIHJlZHVuZGFu dCB0b28sIGFyZW4ndCB5b3U/Cj4+Cj4+IMKgRnJvbSBhIHF1aWNrIGxvb2ssIGl0IHNlZW1zIHRv IG1lIGFzIHdlbGwgdGhhdCBpdCB3b3VsZCBiZS4gSSdtIG9rCj4+IHRha2luZyBjYXJlIG9mIGl0 LCBub3Qgc3VyZSBpZiBpbiB0aGlzIHBhdGNoLCBvciBpbiBhbm90aGVyIG9uZS4KPgo+IEkgdGhv dWdodCBBbmRyZXcgYWxyZWFkeSBxdWV1ZWQgdGhpcyBwYXRjaD8KCkkgZGlkLgoKPgo+IEFueXdh eSwgSSB0aGluayB5b3UgYXJlIHJpZ2h0LiBXZSBjYW4gZHJvcCB0aGUgY2hlY2sgaW4KPiBzY2hl ZHVsZV90YWlsKCkgYXMgd2VsbC4KClRoYXQgc2hvdWxkIHJlYWxseSBiZSBhIHNlcGFyYXRlIHBh dGNoLCBiZWNhdXNlIGl0IGlzIEFSTS1zcGVjaWZpYwpzY2hlZHVsaW5nIGJlaGF2aW91ci7CoCBU aGUgc2FtZSBpcyBub3QgdHJ1ZSBvbiB4ODYuCgp+QW5kcmV3CgpfX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fXwpYZW4tZGV2ZWwgbWFpbGluZyBsaXN0Clhlbi1k ZXZlbEBsaXN0cy54ZW5wcm9qZWN0Lm9yZwpodHRwczovL2xpc3RzLnhlbnByb2plY3Qub3JnL21h aWxtYW4vbGlzdGluZm8veGVuLWRldmVs From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10786C43219 for ; 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Fri, 26 Apr 2019 16:26:28 +0000 (UTC) X-IronPort-AV: E=Sophos;i="5.60,398,1549929600"; d="scan'208";a="89345938" To: Julien Grall , Dario Faggioli , Andrii Anisov , References: <155577364571.25746.11988517450711182732.stgit@wayrath> <155577388740.25746.3780283868034526234.stgit@wayrath> From: Andrew Cooper Openpgp: preference=signencrypt Autocrypt: addr=andrew.cooper3@citrix.com; prefer-encrypt=mutual; keydata= mQINBFLhNn8BEADVhE+Hb8i0GV6mihnnr/uiQQdPF8kUoFzCOPXkf7jQ5sLYeJa0cQi6Penp VtiFYznTairnVsN5J+ujSTIb+OlMSJUWV4opS7WVNnxHbFTPYZVQ3erv7NKc2iVizCRZ2Kxn srM1oPXWRic8BIAdYOKOloF2300SL/bIpeD+x7h3w9B/qez7nOin5NzkxgFoaUeIal12pXSR Q354FKFoy6Vh96gc4VRqte3jw8mPuJQpfws+Pb+swvSf/i1q1+1I4jsRQQh2m6OTADHIqg2E ofTYAEh7R5HfPx0EXoEDMdRjOeKn8+vvkAwhviWXTHlG3R1QkbE5M/oywnZ83udJmi+lxjJ5 YhQ5IzomvJ16H0Bq+TLyVLO/VRksp1VR9HxCzItLNCS8PdpYYz5TC204ViycobYU65WMpzWe LFAGn8jSS25XIpqv0Y9k87dLbctKKA14Ifw2kq5OIVu2FuX+3i446JOa2vpCI9GcjCzi3oHV e00bzYiHMIl0FICrNJU0Kjho8pdo0m2uxkn6SYEpogAy9pnatUlO+erL4LqFUO7GXSdBRbw5 gNt25XTLdSFuZtMxkY3tq8MFss5QnjhehCVPEpE6y9ZjI4XB8ad1G4oBHVGK5LMsvg22PfMJ ISWFSHoF/B5+lHkCKWkFxZ0gZn33ju5n6/FOdEx4B8cMJt+cWwARAQABtClBbmRyZXcgQ29v cGVyIDxhbmRyZXcuY29vcGVyM0BjaXRyaXguY29tPokCOgQTAQgAJAIbAwULCQgHAwUVCgkI CwUWAgMBAAIeAQIXgAUCWKD95wIZAQAKCRBlw/kGpdefoHbdD/9AIoR3k6fKl+RFiFpyAhvO 59ttDFI7nIAnlYngev2XUR3acFElJATHSDO0ju+hqWqAb8kVijXLops0gOfqt3VPZq9cuHlh IMDquatGLzAadfFx2eQYIYT+FYuMoPZy/aTUazmJIDVxP7L383grjIkn+7tAv+qeDfE+txL4 SAm1UHNvmdfgL2/lcmL3xRh7sub3nJilM93RWX1Pe5LBSDXO45uzCGEdst6uSlzYR/MEr+5Z JQQ32JV64zwvf/aKaagSQSQMYNX9JFgfZ3TKWC1KJQbX5ssoX/5hNLqxMcZV3TN7kU8I3kjK mPec9+1nECOjjJSO/h4P0sBZyIUGfguwzhEeGf4sMCuSEM4xjCnwiBwftR17sr0spYcOpqET ZGcAmyYcNjy6CYadNCnfR40vhhWuCfNCBzWnUW0lFoo12wb0YnzoOLjvfD6OL3JjIUJNOmJy RCsJ5IA/Iz33RhSVRmROu+TztwuThClw63g7+hoyewv7BemKyuU6FTVhjjW+XUWmS/FzknSi dAG+insr0746cTPpSkGl3KAXeWDGJzve7/SBBfyznWCMGaf8E2P1oOdIZRxHgWj0zNr1+ooF /PzgLPiCI4OMUttTlEKChgbUTQ+5o0P080JojqfXwbPAyumbaYcQNiH1/xYbJdOFSiBv9rpt TQTBLzDKXok86LkCDQRS4TZ/ARAAkgqudHsp+hd82UVkvgnlqZjzz2vyrYfz7bkPtXaGb9H4 Rfo7mQsEQavEBdWWjbga6eMnDqtu+FC+qeTGYebToxEyp2lKDSoAsvt8w82tIlP/EbmRbDVn 7bhjBlfRcFjVYw8uVDPptT0TV47vpoCVkTwcyb6OltJrvg/QzV9f07DJswuda1JH3/qvYu0p vjPnYvCq4NsqY2XSdAJ02HrdYPFtNyPEntu1n1KK+gJrstjtw7KsZ4ygXYrsm/oCBiVW/OgU g/XIlGErkrxe4vQvJyVwg6YH653YTX5hLLUEL1NS4TCo47RP+wi6y+TnuAL36UtK/uFyEuPy wwrDVcC4cIFhYSfsO0BumEI65yu7a8aHbGfq2lW251UcoU48Z27ZUUZd2Dr6O/n8poQHbaTd 6bJJSjzGGHZVbRP9UQ3lkmkmc0+XCHmj5WhwNNYjgbbmML7y0fsJT5RgvefAIFfHBg7fTY/i kBEimoUsTEQz+N4hbKwo1hULfVxDJStE4sbPhjbsPCrlXf6W9CxSyQ0qmZ2bXsLQYRj2xqd1 bpA+1o1j2N4/au1R/uSiUFjewJdT/LX1EklKDcQwpk06Af/N7VZtSfEJeRV04unbsKVXWZAk uAJyDDKN99ziC0Wz5kcPyVD1HNf8bgaqGDzrv3TfYjwqayRFcMf7xJaL9xXedMcAEQEAAYkC HwQYAQgACQUCUuE2fwIbDAAKCRBlw/kGpdefoG4XEACD1Qf/er8EA7g23HMxYWd3FXHThrVQ HgiGdk5Yh632vjOm9L4sd/GCEACVQKjsu98e8o3ysitFlznEns5EAAXEbITrgKWXDDUWGYxd pnjj2u+GkVdsOAGk0kxczX6s+VRBhpbBI2PWnOsRJgU2n10PZ3mZD4Xu9kU2IXYmuW+e5KCA vTArRUdCrAtIa1k01sPipPPw6dfxx2e5asy21YOytzxuWFfJTGnVxZZSCyLUO83sh6OZhJkk b9rxL9wPmpN/t2IPaEKoAc0FTQZS36wAMOXkBh24PQ9gaLJvfPKpNzGD8XWR5HHF0NLIJhgg 4ZlEXQ2fVp3XrtocHqhu4UZR4koCijgB8sB7Tb0GCpwK+C4UePdFLfhKyRdSXuvY3AHJd4CP 4JzW0Bzq/WXY3XMOzUTYApGQpnUpdOmuQSfpV9MQO+/jo7r6yPbxT7CwRS5dcQPzUiuHLK9i nvjREdh84qycnx0/6dDroYhp0DFv4udxuAvt1h4wGwTPRQZerSm4xaYegEFusyhbZrI0U9tJ B8WrhBLXDiYlyJT6zOV2yZFuW47VrLsjYnHwn27hmxTC/7tvG3euCklmkn9Sl9IAKFu29RSo d5bD8kMSCYsTqtTfT6W4A3qHGvIDta3ptLYpIAOD2sY3GYq2nf3Bbzx81wZK14JdDDHUX2Rs 6+ahAA== Message-ID: <04305f60-785d-cd21-1de4-9772f5bda198@citrix.com> Date: Fri, 26 Apr 2019 17:26:25 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-GB X-ClientProxiedBy: AMSPEX02CAS01.citrite.net (10.69.22.112) To AMSPEX02CL02.citrite.net (10.69.22.126) Subject: Re: [Xen-devel] [PATCH 2/2] xen: sched: we never get into context_switch() with prev==next X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , Stefano Stabellini , Wei Liu , George Dunlap , Jan Beulich , =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: base64 Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Message-ID: <20190426162625.OimJdzYENCHsWUHbJWjJIVbgJ7-vORhXRPbQFAxaoCA@z> T24gMjYvMDQvMjAxOSAxNzoyMiwgSnVsaWVuIEdyYWxsIHdyb3RlOgo+IEhpIERhcmlvLAo+Cj4g T24gMjYvMDQvMjAxOSAxNjoxMywgRGFyaW8gRmFnZ2lvbGkgd3JvdGU6Cj4+IE9uIFR1ZSwgMjAx OS0wNC0yMyBhdCAxMjoxMyArMDMwMCwgQW5kcmlpIEFuaXNvdiB3cm90ZToKPj4+IEhlbGxvIERh cmlvLAo+Pj4KPj4+IE9uIDIwLjA0LjE5IDE4OjI0LCBEYXJpbyBGYWdnaW9saSB3cm90ZToKPj4+ PiBJbiBzY2hlZHVsZSgpLCBpZiB3ZSBwaWNrLCBhcyB0aGUgbmV4dCB2Y3B1IHRvIHJ1biAobmV4 dCkgdGhlIHNhbWUKPj4+PiBvbmUKPj4+PiB0aGF0IGlzIHJ1bm5pbmcgYWxyZWFkeSAocHJldiks IHdlIG5ldmVyIGdldCB0byBjYWxsCj4+Pj4gY29udGV4dF9zd2l0Y2goKS4KPj4+Cj4+PiBBbmQg d2hhdCBhYm91dCBgaWYgKCBwcmV2ICE9IGN1cnJlbnQgKWAgaW4KPj4+IGFybS9kb21haW4uYzpz Y2hlZHVsZV90YWlsKCkgPwo+Pj4KPj4gWW91J3JlIHN1Z2dlc3RpbmcgdGhhdCdzIHJlZHVuZGFu dCB0b28sIGFyZW4ndCB5b3U/Cj4+Cj4+IMKgRnJvbSBhIHF1aWNrIGxvb2ssIGl0IHNlZW1zIHRv IG1lIGFzIHdlbGwgdGhhdCBpdCB3b3VsZCBiZS4gSSdtIG9rCj4+IHRha2luZyBjYXJlIG9mIGl0 LCBub3Qgc3VyZSBpZiBpbiB0aGlzIHBhdGNoLCBvciBpbiBhbm90aGVyIG9uZS4KPgo+IEkgdGhv dWdodCBBbmRyZXcgYWxyZWFkeSBxdWV1ZWQgdGhpcyBwYXRjaD8KCkkgZGlkLgoKPgo+IEFueXdh eSwgSSB0aGluayB5b3UgYXJlIHJpZ2h0LiBXZSBjYW4gZHJvcCB0aGUgY2hlY2sgaW4KPiBzY2hl ZHVsZV90YWlsKCkgYXMgd2VsbC4KClRoYXQgc2hvdWxkIHJlYWxseSBiZSBhIHNlcGFyYXRlIHBh dGNoLCBiZWNhdXNlIGl0IGlzIEFSTS1zcGVjaWZpYwpzY2hlZHVsaW5nIGJlaGF2aW91ci7CoCBU aGUgc2FtZSBpcyBub3QgdHJ1ZSBvbiB4ODYuCgp+QW5kcmV3CgpfX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fXwpYZW4tZGV2ZWwgbWFpbGluZyBsaXN0Clhlbi1k ZXZlbEBsaXN0cy54ZW5wcm9qZWN0Lm9yZwpodHRwczovL2xpc3RzLnhlbnByb2plY3Qub3JnL21h aWxtYW4vbGlzdGluZm8veGVuLWRldmVs