linux.git/arch/x86/kernel/cpu/resctrl/pseudo_lock.c, branch v5.14

x86/resctrl: Fix kernel-doc in pseudo_lock.c

2021-06-24T08:21:05+00:00

Add undocumented parameters detected by scripts/kernel-doc.

Signed-off-by: Fabio M. De Francesco 
Signed-off-by: Borislav Petkov 
Reviewed-by: Reinette Chatre 
Link: https://lkml.kernel.org/r/20210616181530.4094-1-fmdefrancesco@gmail.com

Revert "mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio"

2021-04-30T18:20:39+00:00

This reverts commit cd544fd1dc9293c6702fab6effa63dac1cc67e99.

As discussed in [1] this commit was a no-op because the mapping type was
checked in vma_to_resize before move_vma is ever called.  This meant that
vm_ops->mremap() would never be called on such mappings.  Furthermore,
we've since expanded support of MREMAP_DONTUNMAP to non-anonymous
mappings, and these special mappings are still protected by the existing
check of !VM_DONTEXPAND and !VM_PFNMAP which will result in a -EINVAL.

1. https://lkml.org/lkml/2020/12/28/2340

Link: https://lkml.kernel.org/r/20210323182520.2712101-2-bgeffon@google.com
Signed-off-by: Brian Geffon 
Acked-by: Hugh Dickins 
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Alejandro Colomar 
Cc: Andrea Arcangeli 
Cc: Andy Lutomirski 
Cc: Axel Rasmussen 
Cc: "Kirill A . Shutemov" 
Cc: Lokesh Gidra 
Cc: Michael Kerrisk 
Cc: "Michael S . Tsirkin" 
Cc: Mike Rapoport 
Cc: Minchan Kim 
Cc: Peter Xu 
Cc: Sonny Rao 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

x86: Fix various typos in comments

2021-03-18T14:31:53+00:00

Fix ~144 single-word typos in arch/x86/ code comments.

Doing this in a single commit should reduce the churn.

Signed-off-by: Ingo Molnar 
Cc: Borislav Petkov 
Cc: Thomas Gleixner 
Cc: Peter Zijlstra 
Cc: Paolo Bonzini 
Cc: Bjorn Helgaas 
Cc: linux-kernel@vger.kernel.org

mremap: don't allow MREMAP_DONTUNMAP on special_mappings and aio

2020-12-15T20:13:41+00:00

As kernel expect to see only one of such mappings, any further operations
on the VMA-copy may be unexpected by the kernel.  Maybe it's being on the
safe side, but there doesn't seem to be any expected use-case for this, so
restrict it now.

Link: https://lkml.kernel.org/r/20201013013416.390574-4-dima@arista.com
Fixes: commit e346b3813067 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()")
Signed-off-by: Dmitry Safonov 
Cc: Alexander Viro 
Cc: Andy Lutomirski 
Cc: Brian Geffon 
Cc: Catalin Marinas 
Cc: Dan Carpenter 
Cc: Dan Williams 
Cc: Dave Jiang 
Cc: Hugh Dickins 
Cc: Ingo Molnar 
Cc: Jason Gunthorpe 
Cc: John Hubbard 
Cc: "Kirill A. Shutemov" 
Cc: Mike Kravetz 
Cc: Minchan Kim 
Cc: Ralph Campbell 
Cc: Russell King 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vishal Verma 
Cc: Vlastimil Babka 
Cc: Will Deacon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mmap locking API: convert mmap_sem comments

2020-06-09T16:39:14+00:00

Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse 
Signed-off-by: Andrew Morton 
Reviewed-by: Vlastimil Babka 
Reviewed-by: Daniel Jordan 
Cc: Davidlohr Bueso 
Cc: David Rientjes 
Cc: Hugh Dickins 
Cc: Jason Gunthorpe 
Cc: Jerome Glisse 
Cc: John Hubbard 
Cc: Laurent Dufour 
Cc: Liam Howlett 
Cc: Matthew Wilcox 
Cc: Peter Zijlstra 
Cc: Ying Han 
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds

x86/resctrl: Rename asm/resctrl_sched.h to asm/resctrl.h

2020-05-06T15:45:22+00:00

asm/resctrl_sched.h is dedicated to the code used for configuration
of the CPU resource control state when a task is scheduled.

Rename resctrl_sched.h to resctrl.h in preparation of additions that
will no longer make this file dedicated to work done during scheduling.

No functional change.

Suggested-by: Borislav Petkov 
Signed-off-by: Reinette Chatre 
Signed-off-by: Borislav Petkov 
Link: https://lkml.kernel.org/r/6914e0ef880b539a82a6d889f9423496d471ad1d.1588715690.git.reinette.chatre@intel.com

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

2019-07-09T00:25:53+00:00

Pull x86 cache resource control update from Ingo Molnar:
 "Two cleanup patches"

* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Cleanup cbm_ensure_valid()
  x86/resctrl: Use _ASM_BX to avoid ifdeffery

x86/resctrl: Use _ASM_BX to avoid ifdeffery

2019-06-10T20:36:38+00:00

Use the _ASM_BX macro which expands to either %rbx or %ebx, depending on
the 32-bit or 64-bit config selected.

Signed-off-by: Uros Bizjak 
Signed-off-by: Borislav Petkov 
Acked-by: Reinette Chatre 
Cc: Fenghua Yu 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Thomas Gleixner 
Cc: x86-ml 
Link: https://lkml.kernel.org/r/20190606200044.5730-1-ubizjak@gmail.com

sched/core: Provide a pointer to the valid CPU mask

2019-06-03T09:49:37+00:00

In commit:

  4b53a3412d66 ("sched/core: Remove the tsk_nr_cpus_allowed() wrapper")

the tsk_nr_cpus_allowed() wrapper was removed. There was not
much difference in !RT but in RT we used this to implement
migrate_disable(). Within a migrate_disable() section the CPU mask is
restricted to single CPU while the "normal" CPU mask remains untouched.

As an alternative implementation Ingo suggested to use:

	struct task_struct {
		const cpumask_t		*cpus_ptr;
		cpumask_t		cpus_mask;
        };
with
	t->cpus_ptr = &t->cpus_mask;

In -RT we then can switch the cpus_ptr to:

	t->cpus_ptr = &cpumask_of(task_cpu(p));

in a migration disabled region. The rules are simple:

 - Code that 'uses' ->cpus_allowed would use the pointer.
 - Code that 'modifies' ->cpus_allowed would use the direct mask.

Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Thomas Gleixner 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Link: https://lkml.kernel.org/r/20190423142636.14347-1-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar

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