From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey Brodkin Subject: Do we need to disable preemption in flush_tlb_range()? Date: Thu, 1 Mar 2018 15:13:10 +0000 Message-ID: <1519917189.13866.6.camel@synopsys.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Language: en-US Content-ID: Sender: linux-kernel-owner@vger.kernel.org To: Vineet Gupta Cc: "linux-arch@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-snps-arc@lists.infradead.org" List-Id: linux-arch.vger.kernel.org SGkgVmluZWV0LA0KDQpKdXN0IG5vdGljZWQgdGhhdCBpbiBjb21tZW50cyBmb3Igc21wX2NhbGxf ZnVuY3Rpb25fbWFueSgpIGl0IGlzIHNhaWQgdGhhdA0KcHJlZW1wdGlvbiBtdXN0IGJlIGRpc2Fi bGVkIGR1cmluZyBpdHMgZXhlY3V0aW9uLiBBbmQgdGhhdCBmdW5jdGlvbiBnZXRzIGV4ZWN1dGVk DQphbW9uZyBvdGhlciB3YXlzIGxpa2UgdGhhdDoNCi0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0t PjgtLS0tLS0tLS0tLS0tLS0tLS0tLS0tLQ0KICBmbHVzaF90bGJfcmFuZ2UoKQ0KICAgIC0+IG9u X2VhY2hfY3B1X21hc2soKQ0KICAgICAgICAgLT4gc21wX2NhbGxfZnVuY3Rpb25fbWFueSgpDQot LS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLT44LS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0NCg0KSSdt IG5vdCBzZWVpbmcgcmlnaHQgbm93IGFueSByZWFsIHByb2JsZW0gd2l0aCBjdXJyZW50IGltcGxl bWVudGF0aW9uIGJ1dA0Kc29tZSBhcmNoaXRlY3R1cmVzIGRvIHRoYXQgdGh1cyB0aGUgcXVlc3Rp b24uDQoNCi1BbGV4ZXk= From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey.Brodkin@synopsys.com (Alexey Brodkin) Date: Thu, 1 Mar 2018 15:13:10 +0000 Subject: Do we need to disable preemption in flush_tlb_range()? List-ID: Message-ID: <1519917189.13866.6.camel@synopsys.com> To: linux-snps-arc@lists.infradead.org Hi Vineet, Just noticed that in comments for smp_call_function_many() it is said that preemption must be disabled during its execution. And that function gets executed among other ways like that: -------------------------->8----------------------- flush_tlb_range() -> on_each_cpu_mask() -> smp_call_function_many() -------------------------->8----------------------- I'm not seeing right now any real problem with current implementation but some architectures do that thus the question. -Alexey