From 43312b8ea1c61abbc5e3bdc87fe2e18f755d549d Mon Sep 17 00:00:00 2001 From: James Morse Date: Tue, 11 Mar 2025 18:36:51 +0000 Subject: x86/resctrl: Remove data_width and the tabular format The resctrl architecture code provides a data_width for the controls of each resource. This is used to zero pad all control values in the schemata file so they appear in columns. The same is done with the resource names to complete the visual effect. e.g. | SMBA:0=2048 | L3:0=00ff AMD platforms discover their maximum bandwidth for the MB resource from firmware, but hard-code the data_width to 4. If the maximum bandwidth requires more digits - the tabular format is silently broken. This is also broken when the mba_MBps mount option is used as the field width isn't updated. If new schema are added resctrl will need to be able to determine the maximum width. The benefit of this pretty-printing is questionable. Instead of handling runtime discovery of the data_width for AMD platforms, remove the feature. These fields are always zero padded so should be harmless to remove if the whole field has been treated as a number. In the above example, this would now look like this: | SMBA:0=2048 | L3:0=ff Signed-off-by: James Morse Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Shaopeng Tan Reviewed-by: Tony Luck Reviewed-by: Reinette Chatre Reviewed-by: Fenghua Yu Reviewed-by: Babu Moger Tested-by: Shaopeng Tan Tested-by: Peter Newman Tested-by: Amit Singh Tomar # arm64 Tested-by: Shanker Donthineni # arm64 Tested-by: Babu Moger Link: https://lore.kernel.org/r/20250311183715.16445-7-james.morse@arm.com --- include/linux/resctrl.h | 2 -- 1 file changed, 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index 736b9a9a9464..e1a982adef45 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -214,7 +214,6 @@ enum resctrl_schema_fmt { * @ctrl_domains: RCU list of all control domains for this resource * @mon_domains: RCU list of all monitor domains for this resource * @name: Name to use in "schemata" file. - * @data_width: Character width of data when displaying * @default_ctrl: Specifies default cache cbm or memory B/W percent. * @schema_fmt: Which format string and parser is used for this schema. * @evt_list: List of monitoring events @@ -232,7 +231,6 @@ struct rdt_resource { struct list_head ctrl_domains; struct list_head mon_domains; char *name; - int data_width; u32 default_ctrl; enum resctrl_schema_fmt schema_fmt; struct list_head evt_list; -- cgit v1.2.3