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charset="iso-8859-2" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: siemens.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: AS1PR10MB5675.EURPRD10.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-Network-Message-Id: 41dfc1d3-121f-4ca6-6c73-08db2f705922 X-MS-Exchange-CrossTenant-originalarrivaltime: 28 Mar 2023 09:39:38.1032 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 38ae3bcd-9579-4fd4-adda-b42e1495d55a X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 8fFIkn37dY/09pDNo1i/+LjeBne4LmyKrkXOMWFcJo+PMB1QjVjxDtXVAfefoYQI2WBobawdFabZ8H/oaluPpWf95INIdGnnP2Vybb5KJcY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: GV1PR10MB6123 Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org > > A longer cpu_relax() here would improve things (on arm64 this function= =0A= > > is a no-op) but maybe Thomas or Will have a better idea.=0A= >=0A= > I had a pretty gross cpu_relax() implementation using wfe somewhere on=0A= > LKML, so you could try that if you can dig it up.=0A= =0A= Do you mean cpu_relax() implementation from this email [1] from=0A= Fri, 28 Jul 2017 ?=0A= =0A= I tried to rebase it on recent Linux, but it did not even boot for me.=0A= Only this was printed:=0A= [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x410fd034]=0A= [ 0=0A= =0A= But cpu_relax() implementation from [1] fixes my problem if I use it=0A= only in irq_finalize_oneshot().=0A= =0A= [1] https://lore.kernel.org/lkml/20170728092831.GA24839@arm.com/=0A= =0A= Zdenek Bouska=0A= =0A= --=0A= Siemens, s.r.o=0A= Siemens Advanta Development=