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| author | Babu Moger <babu.moger@amd.com> | 2025-11-12 18:57:35 -0600 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2025-11-22 14:28:31 +0100 |
| commit | 28fa2cce7a8388f09e457f1e24241ca6d5e985d8 (patch) | |
| tree | 5606e726e9b7af020c64fc6f4620745507c22317 /Documentation/filesystems | |
| parent | af1242eeca50b20076d1bc9a41653005634a8a4f (diff) | |
| download | tip-28fa2cce7a8388f09e457f1e24241ca6d5e985d8.tar.gz | |
fs/resctrl: Introduce interface to modify io_alloc capacity bitmasks
The io_alloc feature in resctrl enables system software to configure the
portion of the cache allocated for I/O traffic. When supported, the
io_alloc_cbm file in resctrl provides access to capacity bitmasks (CBMs)
allocated for I/O devices.
Enable users to modify io_alloc CBMs by writing to the io_alloc_cbm resctrl
file when the io_alloc feature is enabled.
Mirror the CBMs between CDP_CODE and CDP_DATA when CDP is enabled to present
consistent I/O allocation information to user space.
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/67609641b03ccfba18a8ee0bf9dbd1f3dcbecda3.1762995456.git.babu.moger@amd.com
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/resctrl.rst | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/Documentation/filesystems/resctrl.rst b/Documentation/filesystems/resctrl.rst index e7994538e0cef7..bbc4b6cbb71dce 100644 --- a/Documentation/filesystems/resctrl.rst +++ b/Documentation/filesystems/resctrl.rst @@ -196,6 +196,18 @@ related to allocation: # cat /sys/fs/resctrl/info/L3/io_alloc_cbm 0=ffff;1=ffff + CBMs can be configured by writing to the interface. + + Example:: + + # echo 1=ff > /sys/fs/resctrl/info/L3/io_alloc_cbm + # cat /sys/fs/resctrl/info/L3/io_alloc_cbm + 0=ffff;1=00ff + + # echo "0=ff;1=f" > /sys/fs/resctrl/info/L3/io_alloc_cbm + # cat /sys/fs/resctrl/info/L3/io_alloc_cbm + 0=00ff;1=000f + 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 |