From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from esa5.hgst.iphmx.com ([216.71.153.144]:27209 "EHLO esa5.hgst.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755200AbeARRN4 (ORCPT ); Thu, 18 Jan 2018 12:13:56 -0500 From: Bart Van Assche To: "snitzer@redhat.com" CC: "dm-devel@redhat.com" , "linux-block@vger.kernel.org" , "ming.lei@redhat.com" Subject: Re: dm rq: Avoid that request processing stalls sporadically Date: Thu, 18 Jan 2018 17:13:53 +0000 Message-ID: <1516295632.2676.16.camel@wdc.com> References: <20180118163707.11825-1-bart.vanassche@wdc.com> <20180118165050.GA19734@redhat.com> In-Reply-To: <20180118165050.GA19734@redhat.com> Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org T24gVGh1LCAyMDE4LTAxLTE4IGF0IDExOjUwIC0wNTAwLCBNaWtlIFNuaXR6ZXIgd3JvdGU6DQo+ IFRoZSBpc3N1ZSB5b3Ugc2F5IGl0IHdhcyBvcmlnaW5hbGx5IGludGVuZGVkIHRvIGZpeCBfc2hv dWxkXyBiZQ0KPiBhZGRyZXNzZWQgd2l0aCB0aGlzIGNoYW5nZToNCj4gaHR0cHM6Ly9naXQua2Vy bmVsLm9yZy9wdWIvc2NtL2xpbnV4L2tlcm5lbC9naXQvZGV2aWNlLW1hcHBlci9saW51eC1kbS5n aXQvY29tbWl0Lz9oPWRtLTQuMTYmaWQ9NGRkNmVkZDIzZTdlYTk3MWVmZGRjMzAzZjllNjdlYjc5 ZTk1ODA4ZQ0KDQpIZWxsbyBNaWtlLA0KDQpTb3JyeSBidXQgSSdtIG5vdCBjb252aW5jZWQgdGhh dCB0aGF0IHBhdGNoIGlzIHN1ZmZpY2llbnQuIFRoYXQgcGF0Y2ggaGVscHMNCmlmIC5lbmRfaW8o KSBpcyBjYWxsZWQgd2l0aCBzdGF0dXMgQkxLX1NUU19SRVNPVVJDRSBhbmQgYWxzbyBpZg0KYmxr X2luc2VydF9jbG9uZWRfcmVxdWVzdCgpIHJldHVybnMgdGhlIC5xdWV1ZV9ycSgpIHJldHVybiB2 YWx1ZS4gSXQgZG9lcyBub3QNCmhlbHAgaWYgLnF1ZXVlX3JxKCkgcmV0dXJucyBCTEtfU1RTX1JF U09VUkNFIGFuZCB0aGF0IHJldHVybiB2YWx1ZSBnZXRzDQppZ25vcmVkLiBJIHRoaW5rIHRoYXQg Y2FuIGhhcHBlbiBhcyBmb2xsb3dzOg0KLSBSZXF1ZXN0IGNsb25pbmcgaW4gbXVsdGlwYXRoX2Ns b25lX2FuZF9tYXAoKSBzdWNjZWVkcyBhbmQgdGhhdCBmdW5jdGlvbg0KICByZXR1cm5zIERNX01B UElPX1JFTUFQUEVELg0KLSBkbV9kaXNwYXRjaF9jbG9uZV9yZXF1ZXN0KCkgY2FsbHMgYmxrX2lu c2VydF9jbG9uZWRfcmVxdWVzdCgpLg0KLSBibGtfaW5zZXJ0X2Nsb25lZF9yZXF1ZXN0KCkgY2Fs bHMgYmxrX21xX3JlcXVlc3RfZGlyZWN0X2lzc3VlKCksIHdoaWNoDQogIHJlc3VsdHMgaW4gYSBj YWxsIG9mIF9fYmxrX21xX3RyeV9pc3N1ZV9kaXJlY3RseSgpLg0KLSBfX2Jsa19tcV90cnlfaXNz dWVfZGlyZWN0bHkoKSBjYWxscyBibGtfbXFfc2NoZWRfaW5zZXJ0X3JlcXVlc3QoKS4gSW4gdGhp cw0KICBjYXNlIHRoZSBCTEtfU1RTX1JFU09VUkNFIHJldHVybmVkIGJ5IHRoZSAucXVldWVfcnEo KSBpbXBsZW1lbnRhdGlvbiBvZiB0aGUNCiAgdW5kZXJseWluZyBwYXRoIHdpbGwgYmUgaWdub3Jl ZC4NCg0KUGxlYXNlIG5vdGUgdGhhdCBJIGhhdmUgbm90IHRyaWVkIHRvIGZpbmQgYWxsIHBhdGhz IHRoYXQgaWdub3JlIHRoZQ0KLnF1ZXVlX3JxKCkgcmV0dXJuIHZhbHVlLg0KDQpUaGFua3MsDQoN CkJhcnQu