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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?4WkhGw0PgdzLngogZLoZ31p5EEJjZTpJjjrGd1r2M32AzBgjyn6qo1QT1w5X?= =?us-ascii?Q?o7XPGfWx1hTDSzGj9ixCsoIPThF/E0AAyAjPVuRcEMEThfgeOqombgTGCAtL?= =?us-ascii?Q?uPsn/RywgD9zdfGFfsvfTtwDoqNQhyTHRydE6UglKPjk1C5WZlKvTn5Is/SK?= =?us-ascii?Q?sPMiO6iLCy91hSASBPJzxKcvskWwA3XOSpqJ6Zi+T2y2jG64NMSYDyRNwZ9T?= =?us-ascii?Q?X4FFkXF12zyxxveVoXMEo5TCZLl3Hk4XFsWKKM6KnsncFR/Dry0c58NgO/LW?= =?us-ascii?Q?DDz0oep9wh4OZDRviNc/kOMeNuiwU14ZQ3VM9iD4RiobxX+AXSK0OwhQU1lq?= =?us-ascii?Q?Oh76Fz8T4gQVIY9RK/A2raqXqXgkMXl8NOvX/crk4lnOwydDANGwl5a9jSi9?= =?us-ascii?Q?YHLFg+235wIQ1dmEQAW2DICX/72+Fa9BjZAQlF8kWVhtnoI80rnsUyFXxpWz?= =?us-ascii?Q?NzD11SAZpSniZjqMfZEEpvLkDil+2VKvR9UGN03rbYtyFPuroTKr7xBZSwd6?= =?us-ascii?Q?v8dMHikdzc0N29Z/SYCO3Hlqd++QbZAk89NgYlY7Ld4BJzi8yqRlJSBcn/v9?= =?us-ascii?Q?mQzdcxt3dP+w0oovU+7GBSGFOWaoAieMEhAqG0nstyBjZj09fcV/LU+OetdL?= =?us-ascii?Q?N5ox6WvPsZOfLmvdvPMoDbRybNTSMtqVgntZUTnfUGus+fFh+pOAorziukvQ?= =?us-ascii?Q?L/VexGdrZDEd/1g5o0zgLRVHcBzwyf98OMfy+S4lp3FlyKqGwo09/qN8aYZG?= =?us-ascii?Q?iKCAzU8StLgZWRFOJcI+yM2GyECgHXvLnGE53Ba9phlc+YOxACQtJdeccNph?= =?us-ascii?Q?DxY1IoQOZ4Vs1q8mySZMdLKO5yGo+8GvnT31IvKD3lFHjqNujfX9hOc6qyol?= =?us-ascii?Q?K9ExJnaQyxjRi17m67TaaWYLj/o9Z0230CGFCxZdewMqexKNPNLV6WePlhK0?= =?us-ascii?Q?61e+Zw2aIqlnZ5tG9F9t/Wj8mI45L4U77XGp0mtIqx9veU0u3hZ03ofAc3hg?= =?us-ascii?Q?fiGk2aDhPX69bEoFWUryXUr1Gl/izW9KRATunlAe53LyIJ11EjwlYIt5Blq2?= =?us-ascii?Q?P1YaasiSm0pEPLin0ce3j3QliIKy7v0yJjDk9JEJ2eUq98CTDdRWjkbcLEAl?= =?us-ascii?Q?3F49CoaFhZXgD56lxGt6ofejOoPVtmwkrOfHGhb1r4GxDxjDlyey+tXFTAUm?= =?us-ascii?Q?lA2jd0qMmLsLPz0R5QVqau4cRQqFJUxj/tVu9dhCSujGgkQnI9tEUIqCXds8?= =?us-ascii?Q?jz/G+Stk1FTZGunXG4T5uJtQPm/b3QeEPx6ahMEuZAvvdquZKeJyc7xwQif0?= =?us-ascii?Q?50IOkKKZIiuNziTUvnArrEof?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 32c22205-b36d-48d9-57a2-08d97d9725d9 X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Sep 2021 07:03:57.9179 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Sf4dMh+25Gj6y+0CaXeYxhsz/LpWuE9c8J9Pg5ESTLbRp2jnOIQH27wUHPbyVQQO4IHwEhjY/qwYF5aKB/UDPA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB5901 On 21.09.2021 22:08, Andrew Cooper wrote: > Not a patch, but an RFC idea for one... >=20 > It occurred to me that the cycles parameter from __trace_var() and > friends is pointless, as the cycles bit is encoded in the top bit of the > event field anyway, and passed in the adjacent parameter. >=20 > Dropping the cycles parameter results in +85/-1029 (-944) net change. >=20 > The common change in callers is e.g. from: >=20 > lea=C2=A0=C2=A0=C2=A0 0x3c(%rsp),%rcx > mov=C2=A0=C2=A0=C2=A0 $0x4,%edx > mov=C2=A0=C2=A0=C2=A0 $0x1,%esi > mov=C2=A0=C2=A0=C2=A0 $0x10f002,%edi > mov=C2=A0=C2=A0=C2=A0 %ebp,0x3c(%rsp) > callq=C2=A0 ffff82d04022ea20 <__trace_var> >=20 > to this: >=20 > lea=C2=A0=C2=A0=C2=A0 0x3c(%rsp),%rdx > mov=C2=A0=C2=A0=C2=A0 $0x4,%esi > mov=C2=A0=C2=A0=C2=A0 $0x8010f002,%edi > mov=C2=A0=C2=A0=C2=A0 %ebp,0x3c(%rsp) > callq=C2=A0 ffff82d04022ea20 <__trace_var> >=20 >=20 > Just sprinkling "| TRC_HD_CYCLE_FLAG" over the place makes things a > little bit unwieldy. >=20 > Instead, I was thinking of implementing trace() (and a thin trace_time() > wrapper) mirroring the "new API" in patch 14.=C2=A0 Half of the trace_var= () > users should be __trace_var() already because of living inside a > tb_init_done conditional, and the rest are actually opencoded TRACE() > taking no extra data. >=20 > Thoughts? Sounds quite reasonable to me. Jan