linux-toradex.git/arch/arc/include/asm/mmu_context.h, branch v6.0-rc1 Linux kernel for Apalis and Colibri modules ARC: mm: move MMU specific bits out of ASID allocator 2021-08-24T21:25:48+00:00 Vineet Gupta vgupta@kernel.org 2019-09-13T22:20:01+00:00 89d0d42412a116563c28c763d9c1bdee83b5b6af And while at it, rewrite commentary on ASID allocator Signed-off-by: Vineet Gupta <vgupta@kernel.org> 
And while at it, rewrite commentary on ASID allocator

Signed-off-by: Vineet Gupta <vgupta@kernel.org>
ARC: mm: use SCRATCH_DATA0 register for caching pgdir in ARCv2 only 2021-08-24T21:25:48+00:00 Vineet Gupta vgupta@kernel.org 2020-01-13T17:16:06+00:00 6128df5be48f48d63efdc7c52022dd163f612373 MMU SCRATCH_DATA0 register is intended to cache task pgd. However in ARC700 SMP port, it has to be repurposed for re-entrant interrupt handling, while UP port doesn't. We currently handle these use-cases using a fabricated #define which has usual issues of dependency nesting and obvious ugliness. So clean this up: for ARC700 don't use to cache pgd (even in UP) and do the opposite for ARCv2. And while here, switch to canonical pgd_offset(). Acked-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Vineet Gupta <vgupta@kernel.org> 
MMU SCRATCH_DATA0 register is intended to cache task pgd. However in
ARC700 SMP port, it has to be repurposed for re-entrant interrupt
handling, while UP port doesn't. We currently handle these use-cases
using a fabricated #define which has usual issues of dependency nesting
and obvious ugliness.

So clean this up: for ARC700 don't use to cache pgd (even in UP) and do
the opposite for ARCv2.

And while here, switch to canonical pgd_offset().

Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Vineet Gupta <vgupta@kernel.org>
arc: use asm-generic/mmu_context.h for no-op implementations 2020-10-26T15:45:05+00:00 Nicholas Piggin npiggin@gmail.com 2020-09-01T14:15:19+00:00 75e6a851d696218a446028ea10339f3039e47a35 Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: linux-snps-arc@lists.infradead.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> 
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: linux-snps-arc@lists.infradead.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
ARCv2: mm: TLB Miss optim: SMP builds can cache pgd pointer in mmu scratch reg 2019-10-28T19:12:31+00:00 Vineet Gupta vgupta@synopsys.com 2014-11-13T13:57:24+00:00 cfd9d70a855edf6adb37d0ed88be9e35274dbe49 ARC700 exception (and intr handling) didn't have auto stack switching thus had to rely on stashing a reg temporarily (to free it up) at a known place in memory, allowing to code up the low level stack switching. This however was not re-entrant in SMP which thus had to repurpose the per-cpu MMU SCRATCH DATA register otherwise used to "cache" the task pdg pointer (vs. reading it from mm struct) The newer HS cores do have auto-stack switching and thus even SMP builds can use the MMU SCRATCH reg as originally intended. This patch fixes the restriction to ARC700 SMP builds only Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
ARC700 exception (and intr handling) didn't have auto stack switching
thus had to rely on stashing a reg temporarily (to free it up) at a
known place in memory, allowing to code up the low level stack switching.
This however was not re-entrant in SMP which thus had to repurpose the
per-cpu MMU SCRATCH DATA register otherwise used to "cache" the task pdg
pointer (vs. reading it from mm struct)

The newer HS cores do have auto-stack switching and thus even SMP builds
can use the MMU SCRATCH reg as originally intended.

This patch fixes the restriction to ARC700 SMP builds only

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19T15:09:55+00:00 Thomas Gleixner tglx@linutronix.de 2019-06-04T08:11:33+00:00 d2912cb15bdda8ba4a5dd73396ad62641af2f520 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sched/headers: Prepare for new header dependencies before moving code to <linux/sched/mm.h> 2017-03-02T07:42:28+00:00 Ingo Molnar mingo@kernel.org 2017-02-08T17:51:29+00:00 6e84f31522f931027bf695752087ece278c10d3f We are going to split <linux/sched/mm.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/mm.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. The APIs that are going to be moved first are: mm_alloc() __mmdrop() mmdrop() mmdrop_async_fn() mmdrop_async() mmget_not_zero() mmput() mmput_async() get_task_mm() mm_access() mm_release() Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> 
We are going to split <linux/sched/mm.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/mm.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

The APIs that are going to be moved first are:

   mm_alloc()
   __mmdrop()
   mmdrop()
   mmdrop_async_fn()
   mmdrop_async()
   mmget_not_zero()
   mmput()
   mmput_async()
   get_task_mm()
   mm_access()
   mm_release()

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix typos 2016-05-30T04:37:32+00:00 Andrea Gelmini andrea.gelmini@gelma.net 2016-05-21T11:45:35+00:00 2547476a5e4061f6addb88d5fc837d3a950f54c4 Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC: [SMP] TLB flush 2013-11-06T05:11:45+00:00 Vineet Gupta vgupta@synopsys.com 2013-10-27T09:19:02+00:00 5ea72a90261552ed5fdca35239feb6cba498301e - Add mm_cpumask setting (aggregating only, unlike some other arches) used to restrict the TLB flush cross-calling - cross-calling versions of TLB flush routines (thanks to Noam) Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
- Add mm_cpumask setting (aggregating only, unlike some other arches)
  used to restrict the TLB flush cross-calling

- cross-calling versions of TLB flush routines (thanks to Noam)

Signed-off-by: Noam Camus <noamc@ezchip.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC: [SMP] ASID allocation 2013-11-06T05:11:45+00:00 Vineet Gupta vgupta@synopsys.com 2013-08-23T13:46:34+00:00 63eca94ca206e342bad4a06a86d8e7eda3053a4e -Track a Per CPU ASID counter -mm-per-cpu ASID (multiple threads, or mm migrated around) Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
-Track a Per CPU ASID counter
-mm-per-cpu ASID (multiple threads, or mm migrated around)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC: [ASID] Track ASID allocation cycles/generations 2013-08-30T16:12:19+00:00 Vineet Gupta vgupta@synopsys.com 2013-07-25T22:45:50+00:00 947bf103fcd2defa3bc4b7ebc6b05d0427bcde2d This helps remove asid-to-mm reverse map While mm->context.id contains the ASID assigned to a process, our ASID allocator also used asid_mm_map[] reverse map. In a new allocation cycle (mm->ASID >= @asid_cache), the Round Robin ASID allocator used this to check if new @asid_cache belonged to some mm2 (from prev cycle). If so, it could locate that mm using the ASID reverse map, and mark that mm as unallocated ASID, to force it to refresh at the time of switch_mm() However, for SMP, the reverse map has to be maintained per CPU, so becomes 2 dimensional, hence got rid of it. With reverse map gone, it is NOT possible to reach out to current assignee. So we track the ASID allocation generation/cycle and on every switch_mm(), check if the current generation of CPU ASID is same as mm's ASID; If not it is refreshed. (Based loosely on arch/sh implementation) Signed-off-by: Vineet Gupta <vgupta@synopsys.com> 
This helps remove asid-to-mm reverse map

While mm->context.id contains the ASID assigned to a process, our ASID
allocator also used asid_mm_map[] reverse map. In a new allocation
cycle (mm->ASID >= @asid_cache), the Round Robin ASID allocator used this
to check if new @asid_cache belonged to some mm2 (from prev cycle).
If so, it could locate that mm using the ASID reverse map, and mark that
mm as unallocated ASID, to force it to refresh at the time of switch_mm()

However, for SMP, the reverse map has to be maintained per CPU, so
becomes 2 dimensional, hence got rid of it.

With reverse map gone, it is NOT possible to reach out to current
assignee. So we track the ASID allocation generation/cycle and
on every switch_mm(), check if the current generation of CPU ASID is
same as mm's ASID; If not it is refreshed.

(Based loosely on arch/sh implementation)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>