linux.git/arch/x86/kernel/cpu/resctrl, branch v6.8

Merge tag 'x86_cache_for_6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-10-30T22:07:29+00:00

Pull x86 resource control updates from Borislav Petkov:

 - Add support for non-contiguous capacity bitmasks being added to
   Intel's CAT implementation

 - Other improvements to resctrl code: better configuration,
   simplifications, debugging support, fixes

* tag 'x86_cache_for_6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Display RMID of resource group
  x86/resctrl: Add support for the files of MON groups only
  x86/resctrl: Display CLOSID for resource group
  x86/resctrl: Introduce "-o debug" mount option
  x86/resctrl: Move default group file creation to mount
  x86/resctrl: Unwind properly from rdt_enable_ctx()
  x86/resctrl: Rename rftype flags for consistency
  x86/resctrl: Simplify rftype flag definitions
  x86/resctrl: Add multiple tasks to the resctrl group at once
  Documentation/x86: Document resctrl's new sparse_masks
  x86/resctrl: Add sparse_masks file in info
  x86/resctrl: Enable non-contiguous CBMs in Intel CAT
  x86/resctrl: Rename arch_has_sparse_bitmaps
  x86/resctrl: Fix remaining kernel-doc warnings

x86/resctrl: Display RMID of resource group

2023-10-17T12:05:40+00:00

In x86, hardware uses RMID to identify a monitoring group. When a user
creates a monitor group these details are not visible. These details
can help resctrl debugging.

Add RMID(mon_hw_id) to the monitor groups display in the resctrl interface.
Users can see these details when resctrl is mounted with "-o debug" option.

Add RFTYPE_MON_BASE that complements existing RFTYPE_CTRL_BASE and
represents files belonging to monitoring groups.

Other architectures do not use "RMID". Use the name mon_hw_id to refer
to "RMID" in an effort to keep the naming generic.

For example:
  $cat /sys/fs/resctrl/mon_groups/mon_grp1/mon_hw_id
  3

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-10-babu.moger@amd.com

x86/resctrl: Add support for the files of MON groups only

2023-10-17T12:05:24+00:00

Files unique to monitoring groups have the RFTYPE_MON flag. When a new
monitoring group is created the resctrl files with flags RFTYPE_BASE
(files common to all resource groups) and RFTYPE_MON (files unique to
monitoring groups) are created to support interacting with the new
monitoring group.

A resource group can support both monitoring and control, also termed
a CTRL_MON resource group. CTRL_MON groups should get both monitoring
and control resctrl files but that is not the case. Only the
RFTYPE_BASE and RFTYPE_CTRL files are created for CTRL_MON groups.

Ensure that files with the RFTYPE_MON flag are created for CTRL_MON groups.

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Ilpo Järvinen 
Reviewed-by: Reinette Chatre 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-9-babu.moger@amd.com

x86/resctrl: Display CLOSID for resource group

2023-10-17T12:05:14+00:00

In x86, hardware uses CLOSID to identify a control group. When a user
creates a control group this information is not visible to the user. It
can help resctrl debugging.

Add CLOSID(ctrl_hw_id) to the control groups display in the resctrl
interface. Users can see this detail when resctrl is mounted with the
"-o debug" option.

Other architectures do not use "CLOSID". Use the names ctrl_hw_id to refer
to "CLOSID" in an effort to keep the naming generic.

For example:
  $cat /sys/fs/resctrl/ctrl_grp1/ctrl_hw_id
  1

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-8-babu.moger@amd.com

x86/resctrl: Introduce "-o debug" mount option

2023-10-17T11:07:17+00:00

Add "-o debug" option to mount resctrl filesystem in debug mode.  When
in debug mode resctrl displays files that have the new RFTYPE_DEBUG flag
to help resctrl debugging.

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-7-babu.moger@amd.com

x86/resctrl: Move default group file creation to mount

2023-10-17T10:50:53+00:00

The default resource group and its files are created during kernel init
time. Upcoming changes will make some resctrl files optional based on
a mount parameter. If optional files are to be added to the default
group based on the mount option, then each new file needs to be created
separately and call kernfs_activate() again.

Create all files of the default resource group during resctrl mount,
destroyed during unmount, to avoid scattering resctrl file addition
across two separate code flows.

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-6-babu.moger@amd.com

x86/resctrl: Unwind properly from rdt_enable_ctx()

2023-10-17T10:49:02+00:00

rdt_enable_ctx() enables the features provided during resctrl mount.

Additions to rdt_enable_ctx() are required to also modify error paths
of rdt_enable_ctx() callers to ensure correct unwinding if errors
are encountered after calling rdt_enable_ctx(). This is error prone.

Introduce rdt_disable_ctx() to refactor the error unwinding of
rdt_enable_ctx() to simplify future additions. This also simplifies
cleanup in rdt_kill_sb().

Suggested-by: Reinette Chatre 
Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-5-babu.moger@amd.com

x86/resctrl: Rename rftype flags for consistency

2023-10-17T09:59:14+00:00

resctrl associates rftype flags with its files so that files can be chosen
based on the resource, whether it is info or base, and if it is control
or monitor type file. These flags use the RF_ as well as RFTYPE_ prefixes.

Change the prefix to RFTYPE_ for all these flags to be consistent.

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-4-babu.moger@amd.com

x86/resctrl: Simplify rftype flag definitions

2023-10-17T09:51:16+00:00

The rftype flags are bitmaps used for adding files under the resctrl
filesystem. Some of these bitmap defines have one extra level of
indirection which is not necessary.

Drop the RF_* defines and simplify the macros.

  [ bp: Massage commit message. ]

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-3-babu.moger@amd.com

x86/resctrl: Add multiple tasks to the resctrl group at once

2023-10-17T09:27:50+00:00

The resctrl task assignment for monitor or control group needs to be
done one at a time. For example:

  $mount -t resctrl resctrl /sys/fs/resctrl/
  $mkdir /sys/fs/resctrl/ctrl_grp1
  $echo 123 > /sys/fs/resctrl/ctrl_grp1/tasks
  $echo 456 > /sys/fs/resctrl/ctrl_grp1/tasks
  $echo 789 > /sys/fs/resctrl/ctrl_grp1/tasks

This is not user-friendly when dealing with hundreds of tasks.

Support multiple task assignment in one command with tasks ids separated
by commas. For example:

  $echo 123,456,789 > /sys/fs/resctrl/ctrl_grp1/tasks

Signed-off-by: Babu Moger 
Signed-off-by: Borislav Petkov (AMD) 
Reviewed-by: Peter Newman 
Reviewed-by: Tan Shaopeng 
Reviewed-by: Fenghua Yu 
Reviewed-by: Reinette Chatre 
Reviewed-by: Ilpo Järvinen 
Tested-by: Peter Newman 
Tested-by: Tan Shaopeng 
Link: https://lore.kernel.org/r/20231017002308.134480-2-babu.moger@amd.com