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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Jan 2026 21:13:28.9365 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 79b753ea-6ab7-4e69-957e-08de5931ec8d X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ1PEPF00001CE7.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB5604 Content-Type: text/plain; charset="utf-8" While min_bandwidth is exposed for each resource under /sys/fs/resctrl, the maximum supported bandwidth is not currently shown. Add max_bandwidth to report the maximum bandwidth permitted for a resource. This helps users understand the limits of the associated resource control group. Signed-off-by: Babu Moger --- Documentation/filesystems/resctrl.rst | 6 +++++- fs/resctrl/rdtgroup.c | 17 +++++++++++++++++ 2 files changed, 22 insertions(+), 1 deletion(-) diff --git a/Documentation/filesystems/resctrl.rst b/Documentation/filesyst= ems/resctrl.rst index 45dde8774128..94187dd3c244 100644 --- a/Documentation/filesystems/resctrl.rst +++ b/Documentation/filesystems/resctrl.rst @@ -224,7 +224,11 @@ Memory bandwidth(MB) subdirectory contains the followi= ng files with respect to allocation: =20 "min_bandwidth": - The minimum memory bandwidth percentage which + The minimum memory bandwidth percentage or units which + user can request. + +"max_bandwidth": + The maximum memory bandwidth percentage or units which user can request. =20 "bandwidth_gran": diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c index ae6c515f4c19..d2eab9007cc1 100644 --- a/fs/resctrl/rdtgroup.c +++ b/fs/resctrl/rdtgroup.c @@ -1153,6 +1153,16 @@ static int rdt_min_bw_show(struct kernfs_open_file *= of, return 0; } =20 +static int rdt_max_bw_show(struct kernfs_open_file *of, + struct seq_file *seq, void *v) +{ + struct resctrl_schema *s =3D rdt_kn_parent_priv(of->kn); + struct rdt_resource *r =3D s->res; + + seq_printf(seq, "%u\n", r->membw.max_bw); + return 0; +} + static int rdt_num_rmids_show(struct kernfs_open_file *of, struct seq_file *seq, void *v) { @@ -1959,6 +1969,13 @@ static struct rftype res_common_files[] =3D { .seq_show =3D rdt_min_bw_show, .fflags =3D RFTYPE_CTRL_INFO | RFTYPE_RES_MB, }, + { + .name =3D "max_bandwidth", + .mode =3D 0444, + .kf_ops =3D &rdtgroup_kf_single_ops, + .seq_show =3D rdt_max_bw_show, + .fflags =3D RFTYPE_CTRL_INFO | RFTYPE_RES_MB, + }, { .name =3D "bandwidth_gran", .mode =3D 0444, --=20 2.34.1