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[209.85.167.42]) by smtp.gmail.com with ESMTPSA id a17sm1127648ljp.129.2020.10.16.11.24.18 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Oct 2020 11:24:19 -0700 (PDT) Received: by mail-lf1-f42.google.com with SMTP id j30so4142939lfp.4 for ; Fri, 16 Oct 2020 11:24:18 -0700 (PDT) X-Received: by 2002:a19:cbcb:: with SMTP id b194mr2024112lfg.133.1602872658198; Fri, 16 Oct 2020 11:24:18 -0700 (PDT) MIME-Version: 1.0 References: <4794a3fa3742a5e84fb0f934944204b55730829b.camel@lca.pw> <20201015151606.GA226448@redhat.com> <20201015195526.GC226448@redhat.com> <20201016181908.GA282856@redhat.com> In-Reply-To: <20201016181908.GA282856@redhat.com> From: Linus Torvalds Date: Fri, 16 Oct 2020 11:24:02 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: Possible deadlock in fuse write path (Was: Re: [PATCH 0/4] Some more lock_page work..) To: Vivek Goyal Cc: Miklos Szeredi , Qian Cai , Hugh Dickins , Matthew Wilcox , "Kirill A . Shutemov" , Linux-MM , Andrew Morton , linux-fsdevel , Amir Goldstein Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Oct 16, 2020 at 11:19 AM Vivek Goyal wrote: > > So with multi page writes performance seems much better for this > particular workload. Looking at that code, I don't see why the page needs to be unlocked after it's been filled, so I do think the easy solution is to just always unlock the pages. Then the rest of the multi-page code is probably fine. But hey, who knows. I might be missing something. Linus