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charset="us-ascii" Content-ID: <3F987864893FA84898C6B92CCEE1853F@namprd15.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 41ecc687-2bbb-4fb6-7ac9-08d6a7e0f1f0 X-MS-Exchange-CrossTenant-originalarrivaltime: 13 Mar 2019 18:23:09.6178 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB3192 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-03-13_11:,, signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe 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 Wed, Mar 13, 2019 at 12:00:17PM -0400, Johannes Weiner wrote: > On Tue, Mar 12, 2019 at 03:34:02PM -0700, Roman Gushchin wrote: > > Flush percpu stats and events data to corresponding before releasing > > percpu memory. > >=20 > > Although per-cpu stats are never exactly precise, dropping them on > > floor regularly may lead to an accumulation of an error. So, it's > > safer to flush them before releasing. > >=20 > > To minimize the number of atomic updates, let's sum all stats/events > > on all cpus locally, and then make a single update per entry. > >=20 > > Signed-off-by: Roman Gushchin >=20 > Acked-by: Johannes Weiner >=20 > Do you mind merging 6/6 into this one? That would make it easier to > verify that the code added in this patch and the code removed in 6/6 > are indeed functionally equivalent. >=20 I did try, but the result is the mess of added and removed lines, which are *almost* the same, but are slightly different (e.g. tabs). So it's much easier to review it as two separate patches. Thanks!