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b=krE6JAQ0OZVHWVWC1nNKQBIM0kq3ujcF8o1RX3BwwG1LiN0Tv71PBTQRsaoP3RhxlVuJ5G68B0ViAtPryGXdi4IDZxL/jU/LKLphBHzvWmXmcjUFhHb0DsV7oQGz5hPf94Z6lX+UmyEN8U/x5/2RPLsohMjX8hgMqpCZILJdLMA= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from MN0PR12MB6101.namprd12.prod.outlook.com (2603:10b6:208:3cb::10) by CH3PR12MB7665.namprd12.prod.outlook.com (2603:10b6:610:14a::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8857.21; Wed, 9 Jul 2025 16:08:52 +0000 Received: from MN0PR12MB6101.namprd12.prod.outlook.com ([fe80::37ee:a763:6d04:81ca]) by MN0PR12MB6101.namprd12.prod.outlook.com ([fe80::37ee:a763:6d04:81ca%3]) with mapi id 15.20.8901.024; Wed, 9 Jul 2025 16:08:52 +0000 Message-ID: <0bb800f5-fa0b-4fb1-8a8b-f65e698d587a@amd.com> Date: Wed, 9 Jul 2025 12:08:49 -0400 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 3/5] PM: hibernate: shrink shmem pages after dev_pm_ops.prepare() To: Samuel Zhang , alexander.deucher@amd.com, christian.koenig@amd.com, rafael@kernel.org, len.brown@intel.com, pavel@kernel.org, gregkh@linuxfoundation.org, dakr@kernel.org, airlied@gmail.com, simona@ffwll.ch, ray.huang@amd.com, matthew.auld@intel.com, matthew.brost@intel.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de Cc: lijo.lazar@amd.com, victor.zhao@amd.com, haijun.chang@amd.com, Qing.Ma@amd.com, Owen.Zhang2@amd.com, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org References: <20250709100512.3762063-1-guoqing.zhang@amd.com> <20250709100512.3762063-4-guoqing.zhang@amd.com> Content-Language: en-US From: Mario Limonciello In-Reply-To: <20250709100512.3762063-4-guoqing.zhang@amd.com> Content-Type: text/plain; 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These shmem pages take a lot > of system memory so that there's no enough free memory for creating the > hibernation image. This will cause hibernation fail and abort. > > After dev_pm_ops.prepare(), call shrink_all_memory() to force move shmem > pages to swap disk and reclaim the pages, so that there's enough system > memory for hibernation image and less pages needed to copy to the image. > > This patch can only flush and free about half shmem pages. It will be > better to flush and free more pages, even all of shmem pages, so that > there're less pages to be copied to the hibernation image and the overall > hibernation time can be reduced. > > Signed-off-by: Samuel Zhang > Acked-by: Rafael J. Wysocki What is your base for this patch? I wanted to get it tested but I tried on top of the latest 6.16-rc as well as linux-next but couldn't apply it on either. I suspect you're missing both 12ffc3b1513ebc1f11ae77d053948504a94a68a6 and e9cec4487cb789645a8c84b13a9ce54c2d89e3bb in your base. Could you please rebase on something newer? > --- > kernel/power/hibernate.c | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c > index 10a01af63a80..7ae9d9a7aa1d 100644 > --- a/kernel/power/hibernate.c > +++ b/kernel/power/hibernate.c > @@ -370,6 +370,23 @@ static int create_image(int platform_mode) > return error; > } > > +static void shrink_shmem_memory(void) > +{ > + struct sysinfo info; > + unsigned long nr_shmem_pages, nr_freed_pages; > + > + si_meminfo(&info); > + nr_shmem_pages = info.sharedram; /* current page count used for shmem */ > + /* > + * The intent is to reclaim all shmem pages. Though shrink_all_memory() can > + * only reclaim about half of them, it's enough for creating the hibernation > + * image. > + */ > + nr_freed_pages = shrink_all_memory(nr_shmem_pages); > + pr_debug("requested to reclaim %lu shmem pages, actually freed %lu pages\n", > + nr_shmem_pages, nr_freed_pages); > +} > + > /** > * hibernation_snapshot - Quiesce devices and create a hibernation image. > * @platform_mode: If set, use platform driver to prepare for the transition. > @@ -411,6 +428,15 @@ int hibernation_snapshot(int platform_mode) > goto Thaw; > } > > + /* > + * Device drivers may move lots of data to shmem in dpm_prepare(). The shmem > + * pages will use lots of system memory, causing hibernation image creation > + * fail due to insufficient free memory. > + * This call is to force flush the shmem pages to swap disk and reclaim > + * the system memory so that image creation can succeed. > + */ > + shrink_shmem_memory(); > + > suspend_console(); > pm_restrict_gfp_mask(); >