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charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SA1PR15MB5109.namprd15.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: be9acd25-1738-4617-9940-08d963417979 X-MS-Exchange-CrossTenant-originalarrivaltime: 19 Aug 2021 18:45:11.0815 (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-CrossTenant-userprincipalname: Mim6utmp/lBh7SwR7Kz5ievn1YuvNSmGHrAhohokrAObxa2BIKGqoeFvAJhWsgtPaZkgqaxbYGGXoWDM5BOTLA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR15MB5061 X-OriginatorOrg: fb.com X-Proofpoint-ORIG-GUID: h5nvOR7XNrQmZTXq68mPHl-ZyO17P9ym X-Proofpoint-GUID: h5nvOR7XNrQmZTXq68mPHl-ZyO17P9ym X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.790 definitions=2021-08-19_06:2021-08-17,2021-08-19 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 suspectscore=0 malwarescore=0 spamscore=0 priorityscore=1501 lowpriorityscore=0 phishscore=0 bulkscore=0 mlxscore=0 impostorscore=0 clxscore=1015 mlxlogscore=579 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2107140000 definitions=main-2108190109 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, > On Aug 19, 2021, at 11:27 AM, Peter Zijlstra wrote= : >=20 > On Thu, Aug 19, 2021 at 06:22:07PM +0000, Song Liu wrote: >=20 >>> And if we're going to be adding new pmu::methods then I figure one that >>> does the whole sample state might be more useful. >>=20 >> What do you mean by "whole sample state"? To integrate with exiting >> perf_sample_data, like perf_output_sample()? >=20 > Yeah, the PMI can/does set more than data->br_stack, but I'm now > thinking that without an actual PMI, much of that will not be possible. > br_stack is special here. >=20 > Oh well, carry on I suppose. Thanks again for these information and suggestions. I will try to put them together in the code and send the patches.=20 Song