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s=dreamhost; t=1790551559; bh=2aSMKRCkja4n/VQgEqybQKvbi5xmjbGNpO1qSHqKYOE=; h=Date:From:To:Cc:Subject:Content-Type; b=E+D62Z35SRdU9cbMZcyXmBaunm2mvKP6J/oet/VsA6QZtvpQwYiEdMZMRoUyLl9Pz uGITOgk2tDjNSsp9tdRkBGg4y2L7K+YFz1cXx3R0R9pMihP53UfFaKg3JZ9g/WjnXY bcTgNtyFfYThp8vCi3wl7ZJVW/h4izJx6J0VkjOEFQz7dopOc4zhI+v6skKcKCaXDS RyKMidAKbn/kGxoRSsNIEfysltrVy52mlJg/87pJOEKLXJbqVrGOiBRj0uIyPfsowV MjgaZdMkHoRckeINWirahjclE9pC4kxzb+4eiVSZc0QEEgVNK4fFw9risHFiKtRpR7 77xkxd7s/yiyw== Date: Sun, 27 Sep 2026 16:25:52 -0700 From: Davidlohr Bueso To: Bharata B Rao Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Jonathan.Cameron@huawei.com, dave.hansen@intel.com, gourry@gourry.net, mgorman@techsingularity.net, mingo@redhat.com, peterz@infradead.org, raghavendra.kt@amd.com, riel@surriel.com, rientjes@google.com, sj@kernel.org, weixugc@google.com, willy@infradead.org, ying.huang@linux.alibaba.com, ziy@nvidia.com, nifan.cxl@gmail.com, xuezhengchu@huawei.com, yiannis@zptcorp.com, akpm@linux-foundation.org, david@kernel.org, byungchul@sk.com, kinseyho@google.com, joshua.hahnjy@gmail.com, yuanchu@google.com, balbirs@nvidia.com, alok.rathore@samsung.com, shivankg@amd.com, donettom@linux.ibm.com Subject: Re: [PATCH v8 3/8] mm: Hot page tracking and promotion - pghot Message-ID: <20260927232552.u6iypdeadjf4nyla@offworld> References: <20260728054356.291998-1-bharata@amd.com> <20260728054356.291998-4-bharata@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20260728054356.291998-4-bharata@amd.com> User-Agent: NeoMutt/20220429 On Tue, 28 Jul 2026, Bharata B Rao wrote: >+/** >+ * pghot_record_access() - Record page accesses from lower tier memory >+ * for the purpose of tracking page hotness and subsequent promotion. >+ * >+ * @pfn: PFN of the page >+ * @nid: Unused >+ * @src: The identifier of the sub-system that reports the access >+ * @now: Access time in jiffies >+ * >+ * Updates the frequency and time of access and marks the page as >+ * ready for migration if the frequency crosses a threshold. The pages >+ * marked for migration are migrated by kmigrated kernel thread. >+ * >+ * Return: 0 on success and -EINVAL on failure to record the access. >+ */ >+int pghot_record_access(unsigned long pfn, int nid, int src, unsigned long now) >+{ [...] >+} This needs a EXPORT_SYMBOL_GPL(pghot_record_access) for any module based sources. Thanks, Davidlohr