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| author | Babu Moger <babu.moger@amd.com> | 2025-11-12 18:57:33 -0600 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2025-11-22 11:37:21 +0100 |
| commit | 77b662326200135fe72cedc47fb1b0e5679d604d (patch) | |
| tree | 135b5ca85a3ae13d0dd72a1c64911317e6886793 /Documentation/filesystems | |
| parent | 9445c7059c1c3b097ec8e924eb374df84770bee5 (diff) | |
| download | tip-77b662326200135fe72cedc47fb1b0e5679d604d.tar.gz | |
fs/resctrl: Introduce interface to display io_alloc CBMs
Introduce the "io_alloc_cbm" resctrl file to display the capacity bitmasks
(CBMs) that represent the portions of each cache instance allocated
for I/O traffic on a cache resource that supports the "io_alloc" feature.
io_alloc_cbm resides in the info directory of a cache resource, for example,
/sys/fs/resctrl/info/L3/. Since the resource name is part of the path, it
is not necessary to display the resource name as done in the schemata file.
When CDP is enabled, io_alloc routes traffic using the highest CLOSID
associated with the CDP_CODE resource and that CLOSID becomes unusable for
the CDP_DATA resource. The highest CLOSID of CDP_CODE and CDP_DATA resources
will be kept in sync to ensure consistent user interface. In preparation for
this, access the CBMs for I/O traffic through highest CLOSID of either
CDP_CODE or CDP_DATA resource.
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://patch.msgid.link/55a3ff66a70e7ce8239f022e62b334e9d64af604.1762995456.git.babu.moger@amd.com
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/resctrl.rst | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/Documentation/filesystems/resctrl.rst b/Documentation/filesystems/resctrl.rst index 91c71e254bbd76..e7994538e0cef7 100644 --- a/Documentation/filesystems/resctrl.rst +++ b/Documentation/filesystems/resctrl.rst @@ -182,6 +182,25 @@ related to allocation: available for general (CPU) cache allocation for both the CDP_CODE and CDP_DATA resources. +"io_alloc_cbm": + Capacity bitmasks that describe the portions of cache instances to + which I/O traffic from supported I/O devices are routed when "io_alloc" + is enabled. + + CBMs are displayed in the following format: + + <cache_id0>=<cbm>;<cache_id1>=<cbm>;... + + Example:: + + # cat /sys/fs/resctrl/info/L3/io_alloc_cbm + 0=ffff;1=ffff + + When CDP is enabled "io_alloc_cbm" associated with the CDP_DATA and CDP_CODE + resources may reflect the same values. For example, values read from and + written to /sys/fs/resctrl/info/L3DATA/io_alloc_cbm may be reflected by + /sys/fs/resctrl/info/L3CODE/io_alloc_cbm and vice versa. + Memory bandwidth(MB) subdirectory contains the following files with respect to allocation: |