linux.git/arch/x86/kernel/cpu/resctrl, branch v5.1

x86/resctrl: Do not repeat rdtgroup mode initialization

2019-04-14T16:23:13+00:00

When cache allocation is supported and the user creates a new resctrl
resource group, the allocations of the new resource group are
initialized to all regions that it can possibly use. At this time these
regions are all that are shareable by other resource groups as well as
regions that are not currently used. The new resource group's mode is
also initialized to reflect this initialization and set to "shareable".

The new resource group's mode is currently repeatedly initialized within
the loop that configures the hardware with the resource group's default
allocations.

Move the initialization of the resource group's mode outside the
hardware configuration loop. The resource group's mode is now
initialized only once as the final step to reflect that its configured
allocations are "shareable".

Fixes: 95f0b77efa57 ("x86/intel_rdt: Initialize new resource group with sane defaults")
Signed-off-by: Xiaochen Shen 
Signed-off-by: Borislav Petkov 
Reviewed-by: Fenghua Yu 
Acked-by: Reinette Chatre 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: pei.p.jia@intel.com
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/1554839629-5448-1-git-send-email-xiaochen.shen@intel.com

x86/resctrl: Fix typos in the mba_sc mount option

2019-04-01T16:45:27+00:00

The user can control the MBA memory bandwidth in MBps (Mega
Bytes per second) units of the MBA Software Controller (mba_sc)
by using the "mba_MBps" mount option. For details, see
Documentation/x86/resctrl_ui.txt.

However, commit

  23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context")

changed the mount option name from "mba_MBps" to "mba_mpbs" by mistake.

Change it back from to "mba_MBps" because it is user-visible, and
correct "Opt_mba_mpbs" spelling to "Opt_mba_mbps".

 [ bp: massage commit message. ]

Fixes: 23bf1b6be9c2 ("kernfs, sysfs, cgroup, intel_rdt: Support fs_context")
Signed-off-by: Xiaochen Shen 
Signed-off-by: Borislav Petkov 
Cc: dhowells@redhat.com
Cc: Fenghua Yu 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: pei.p.jia@intel.com
Cc: Reinette Chatre 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/1553896238-22130-1-git-send-email-xiaochen.shen@intel.com

x86/resctrl: Remove unused variable

2019-03-24T21:09:27+00:00

Variable "struct rdt_resource *r" is set but not used. So remove it.

Signed-off-by: Peng Hao 
Signed-off-by: Thomas Gleixner 
Link: https://lkml.kernel.org/r/1552152584-26087-1-git-send-email-peng.hao2@zte.com.cn

Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2019-03-12T21:08:19+00:00

Pull vfs mount infrastructure updates from Al Viro:
 "The rest of core infrastructure; no new syscalls in that pile, but the
  old parts are switched to new infrastructure. At that point
  conversions of individual filesystems can happen independently; some
  are done here (afs, cgroup, procfs, etc.), there's also a large series
  outside of that pile dealing with NFS (quite a bit of option-parsing
  stuff is getting used there - it's one of the most convoluted
  filesystems in terms of mount-related logics), but NFS bits are the
  next cycle fodder.

  It got seriously simplified since the last cycle; documentation is
  probably the weakest bit at the moment - I considered dropping the
  commit introducing Documentation/filesystems/mount_api.txt (cutting
  the size increase by quarter ;-), but decided that it would be better
  to fix it up after -rc1 instead.

  That pile allows to do followup work in independent branches, which
  should make life much easier for the next cycle. fs/super.c size
  increase is unpleasant; there's a followup series that allows to
  shrink it considerably, but I decided to leave that until the next
  cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
  afs: Use fs_context to pass parameters over automount
  afs: Add fs_context support
  vfs: Add some logging to the core users of the fs_context log
  vfs: Implement logging through fs_context
  vfs: Provide documentation for new mount API
  vfs: Remove kern_mount_data()
  hugetlbfs: Convert to fs_context
  cpuset: Use fs_context
  kernfs, sysfs, cgroup, intel_rdt: Support fs_context
  cgroup: store a reference to cgroup_ns into cgroup_fs_context
  cgroup1_get_tree(): separate "get cgroup_root to use" into a separate helper
  cgroup_do_mount(): massage calling conventions
  cgroup: stash cgroup_root reference into cgroup_fs_context
  cgroup2: switch to option-by-option parsing
  cgroup1: switch to option-by-option parsing
  cgroup: take options parsing into ->parse_monolithic()
  cgroup: fold cgroup1_mount() into cgroup1_get_tree()
  cgroup: start switching to fs_context
  ipc: Convert mqueue fs to fs_context
  proc: Add fs_context support to procfs
  ...

Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2019-03-08T00:36:57+00:00

Pull x86 cleanups from Ingo Molnar:
 "Various cleanups and simplifications, none of them really stands out,
  they are all over the place"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/uaccess: Remove unused __addr_ok() macro
  x86/smpboot: Remove unused phys_id variable
  x86/mm/dump_pagetables: Remove the unused prev_pud variable
  x86/fpu: Move init_xstate_size() to __init section
  x86/cpu_entry_area: Move percpu_setup_debug_store() to __init section
  x86/mtrr: Remove unused variable
  x86/boot/compressed/64: Explain paging_prepare()'s return value
  x86/resctrl: Remove duplicate MSR_MISC_FEATURE_CONTROL definition
  x86/asm/suspend: Drop ENTRY from local data
  x86/hw_breakpoints, kprobes: Remove kprobes ifdeffery
  x86/boot: Save several bytes in decompressor
  x86/trap: Remove useless declaration
  x86/mm/tlb: Remove unused cpu variable
  x86/events: Mark expected switch-case fall-throughs
  x86/asm-prototypes: Remove duplicate include 
  x86/kernel: Mark expected switch-case fall-throughs
  x86/insn-eval: Mark expected switch-case fall-through
  x86/platform/UV: Replace kmalloc() and memset() with k[cz]alloc() calls
  x86/e820: Replace kmalloc() + memcpy() with kmemdup()

kernfs, sysfs, cgroup, intel_rdt: Support fs_context

2019-02-28T08:29:34+00:00

Make kernfs support superblock creation/mount/remount with fs_context.

This requires that sysfs, cgroup and intel_rdt, which are built on kernfs,
be made to support fs_context also.

Notes:

 (1) A kernfs_fs_context struct is created to wrap fs_context and the
     kernfs mount parameters are moved in here (or are in fs_context).

 (2) kernfs_mount{,_ns}() are made into kernfs_get_tree().  The extra
     namespace tag parameter is passed in the context if desired

 (3) kernfs_free_fs_context() is provided as a destructor for the
     kernfs_fs_context struct, but for the moment it does nothing except
     get called in the right places.

 (4) sysfs doesn't wrap kernfs_fs_context since it has no parameters to
     pass, but possibly this should be done anyway in case someone wants to
     add a parameter in future.

 (5) A cgroup_fs_context struct is created to wrap kernfs_fs_context and
     the cgroup v1 and v2 mount parameters are all moved there.

 (6) cgroup1 parameter parsing error messages are now handled by invalf(),
     which allows userspace to collect them directly.

 (7) cgroup1 parameter cleanup is now done in the context destructor rather
     than in the mount/get_tree and remount functions.

Weirdies:

 (*) cgroup_do_get_tree() calls cset_cgroup_from_root() with locks held,
     but then uses the resulting pointer after dropping the locks.  I'm
     told this is okay and needs commenting.

 (*) The cgroup refcount web.  This really needs documenting.

 (*) cgroup2 only has one root?

Add a suggestion from Thomas Gleixner in which the RDT enablement code is
placed into its own function.

[folded a leak fix from Andrey Vagin]

Signed-off-by: David Howells 
cc: Greg Kroah-Hartman 
cc: Tejun Heo 
cc: Li Zefan 
cc: Johannes Weiner 
cc: cgroups@vger.kernel.org
cc: fenghua.yu@intel.com
Signed-off-by: Al Viro

x86/resctrl: Remove duplicate MSR_MISC_FEATURE_CONTROL definition

2019-02-05T06:21:56+00:00

The definition of MSR_MISC_FEATURE_CONTROL was first introduced in

  98af74599ea0 ("x86 msr_index.h: Define MSR_MISC_FEATURE_CONTROL")

and present in Linux since v4.11.

The Cache Pseudo-Locking code added this duplicate definition in more
recent

  f2a177292bd0 ("x86/intel_rdt: Discover supported platforms via prefetch disable bits"),

available since v4.19.

Remove the duplicate definition from the resctrl subsystem and let that
code obtain the needed definition from the core architecture msr-index.h
instead.

Fixes: f2a177292bd0 ("x86/intel_rdt: Discover supported platforms via prefetch disable bits")
Signed-off-by: Reinette Chatre 
Signed-off-by: Borislav Petkov 
Cc: Fenghua Yu 
Cc: gavin.hindman@intel.com
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: jithu.joseph@intel.com
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/ff6b95d9b6ef6f4ac96267f130719ba1af09614b.1549312475.git.reinette.chatre@intel.com

x86/resctrl: Avoid confusion over the new X86_RESCTRL config

2019-02-02T09:34:52+00:00

"Resource Control" is a very broad term for this CPU feature, and a term
that is also associated with containers, cgroups etc. This can easily
cause confusion.

Make the user prompt more specific. Match the config symbol name.

 [ bp: In the future, the corresponding ARM arch-specific code will be
   under ARM_CPU_RESCTRL and the arch-agnostic bits will be carved out
   under the CPU_RESCTRL umbrella symbol. ]

Signed-off-by: Johannes Weiner 
Signed-off-by: Borislav Petkov 
Cc: Babu Moger 
Cc: Fenghua Yu 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: James Morse 
Cc: Jonathan Corbet 
Cc: "Kirill A. Shutemov" 
Cc: linux-doc@vger.kernel.org
Cc: Peter Zijlstra 
Cc: Pu Wen 
Cc: Reinette Chatre 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/20190130195621.GA30653@cmpxchg.org

x86/cache: Rename config option to CONFIG_X86_RESCTRL

2019-01-09T09:29:03+00:00

CONFIG_RESCTRL is too generic. The final goal is to have a generic
option called like this which is selected by the arch-specific ones
CONFIG_X86_RESCTRL and CONFIG_ARM64_RESCTRL. The generic one will
cover the resctrl filesystem and other generic and shared bits of
functionality.

Signed-off-by: Borislav Petkov 
Suggested-by: Ingo Molnar 
Requested-by: Linus Torvalds 
Cc: Babu Moger 
Cc: Fenghua Yu 
Cc: James Morse 
Cc: Reinette Chatre 
Cc: Tony Luck 
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20190108171401.GC12235@zn.tnic

Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-12-26T20:17:43+00:00

Pull x86 cache control updates from Borislav Petkov:

 - The generalization of the RDT code to accommodate the addition of
   AMD's very similar implementation of the cache monitoring feature.

   This entails a subsystem move into a separate and generic
   arch/x86/kernel/cpu/resctrl/ directory along with adding
   vendor-specific initialization and feature detection helpers.

   Ontop of that is the unification of user-visible strings, both in the
   resctrl filesystem error handling and Kconfig.

   Provided by Babu Moger and Sherry Hurwitz.

 - Code simplifications and error handling improvements by Reinette
   Chatre.

* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Fix rdt_find_domain() return value and checks
  x86/resctrl: Remove unnecessary check for cbm_validate()
  x86/resctrl: Use rdt_last_cmd_puts() where possible
  MAINTAINERS: Update resctrl filename patterns
  Documentation: Rename and update intel_rdt_ui.txt to resctrl_ui.txt
  x86/resctrl: Introduce AMD QOS feature
  x86/resctrl: Fixup the user-visible strings
  x86/resctrl: Add AMD's X86_FEATURE_MBA to the scattered CPUID features
  x86/resctrl: Rename the config option INTEL_RDT to RESCTRL
  x86/resctrl: Add vendor check for the MBA software controller
  x86/resctrl: Bring cbm_validate() into the resource structure
  x86/resctrl: Initialize the vendor-specific resource functions
  x86/resctrl: Move all the macros to resctrl/internal.h
  x86/resctrl: Re-arrange the RDT init code
  x86/resctrl: Rename the RDT functions and definitions
  x86/resctrl: Rename and move rdt files to a separate directory