Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20200706025921.53683-1-songmuchun@bytedance.com>
In-Reply-To: <20200706025921.53683-1-songmuchun@bytedance.com>
From:   Pekka Enberg <penberg@gmail.com>
Date:   Mon, 6 Jul 2020 14:49:55 +0300
Message-ID: <CAOJsxLEgRvkganmNNmeBsHdgHTgJ5tbK=b8Pnrc4LB3tvTzbMA@mail.gmail.com>
Subject: Re: [PATCH v2] mm/page_alloc: skip setting nodemask when we are in interrupt
To:     Muchun Song <songmuchun@bytedance.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        David Hildenbrand <david@redhat.com>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Jul 6, 2020 at 5:59 AM Muchun Song <songmuchun@bytedance.com> wrote:
> When we are in the interrupt context, it is irrelevant to the
> current task context. If we use current task's mems_allowed, we
> can fair to alloc pages in the fast path and fall back to slow
> path memory allocation when the current node(which is the current
> task mems_allowed) does not have enough memory to allocate. In
> this case, it slows down the memory allocation speed of interrupt
> context. So we can skip setting the nodemask to allow any node
> to allocate memory, so that fast path allocation can success.
>
> Signed-off-by: Muchun Song <songmuchun@bytedance.com>

Reviewed-by: Pekka Enberg <penberg@kernel.org>