[PATCH 1/7] powerpc/lib: move PPC32 specific functions out of string.S

In preparation of optimisation patches, move PPC32 specific memcmp() and __clear_user() into string_32.S Signed-off-by: Christophe Leroy --- arch/powerpc/lib/Makefile| 5 +-- arch/powerpc/lib/string.S| 61 - arch/powerpc/lib/string_32.S | 72 +

[PATCH 2/7] powerpc/lib: inline memcmp() NUL size verification

Many calls to memcmp() are done with constant size. This patch gives GCC a chance to optimise out the NULL size verification. Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/string.h | 10 ++ arch/powerpc/lib/memcmp_64.S | 4 arch/powerpc/lib/string_32.S | 4

[PATCH 3/7] powerpc/lib: optimise PPC32 memcmp

At the time being, memcmp() compares two chunks of memory byte per byte. This patch optimised the comparison by comparing word by word. A small benchmark performed on an 8xx based on the comparison of two chuncks of 512 bytes performed 10 times gives: Before : 5852274 TB ticks After: 14886

[PATCH 4/7] powerpc/lib: inline memcmp() for small constant sizes

In my 8xx configuration, I get 208 calls to memcmp() Within those 208 calls, about half of them have constant sizes, 46 have a size of 8, 17 have a size of 16, only a few have a size over 16. Other fixed sizes are mostly 4, 6 and 10. This patch inlines calls to memcmp() when size is constant and l

[PATCH 5/7] powerpc/lib: optimise 32 bits __clear_user()

Rewrite clear_user() on the same principle as memset(0), making use of dcbz to clear complete cache lines. This code is a copy/paste of memset(), with some modifications in order to retrieve remaining number of bytes to be cleared, as it needs to be returned in case of error. On a MPC885, through

[PATCH 6/7] powerpc/lib: inline more NUL size verifications

strncmp(), strncpy(), memchr() are often called with constant size. This patch gives GCC a chance to optimise NULL size verification out Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/string.h | 24 arch/powerpc/lib/string.S | 8 2 files

[PATCH 7/7] powerpc/lib: Remove .balign inside string functions for PPC32

commit 87a156fb18fe1 ("Align hot loops of some string functions") degraded the performance of string functions by adding useless nops A simple benchmark on an 8xx calling 10x a memchr() that matches the first byte runs in 41668 TB ticks before this patch and in 35986 TB ticks after this patch.

[PATCH] powerpc/misc: get rid of add_reloc_offset()

add_reloc_offset() is almost redundant with reloc_offset() Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/setup.h | 3 +-- arch/powerpc/kernel/misc.S | 16 arch/powerpc/kernel/prom_init_check.sh | 2 +- 3 files changed, 2 insertions(+), 19 delet

[PATCH 1/2] powernv/npu: Do a PID GPU TLB flush when invalidating a large address range

The NPU has a limited number of address translation shootdown (ATSD) registers and the GPU has limited bandwidth to process ATSDs. This can result in contention of ATSD registers leading to soft lockups on some threads, particularly when invalidating a large address range in pnv_npu2_mn_invalidate_

[PATCH 2/2] powernv/npu: Add a debugfs setting to change ATSD threshold

The threshold at which it becomes more efficient to coalesce a range of ATSDs into a single per-PID ATSD is currently not well understood due to a lack of real-world work loads. This patch adds a debugfs parameter allowing the threshold to be altered at runtime in order to aid future development an

Re: [PATCH 1/2] powernv/npu: Do a PID GPU TLB flush when invalidating a large address range

On Tue, Apr 17, 2018 at 7:11 PM, Alistair Popple wrote: > The NPU has a limited number of address translation shootdown (ATSD) > registers and the GPU has limited bandwidth to process ATSDs. This can > result in contention of ATSD registers leading to soft lockups on some > threads, particularly w

Re: [PATCH] powerpc/misc: get rid of add_reloc_offset()

On Tue, Apr 17, 2018 at 09:56:24AM +0200, Christophe Leroy wrote: > add_reloc_offset() is almost redundant with reloc_offset() > > Signed-off-by: Christophe Leroy > --- > arch/powerpc/include/asm/setup.h | 3 +-- > arch/powerpc/kernel/misc.S | 16 > arch/power

[RESEND PATCH 2/3] powerpc: dts: use 'atmel' as at24 manufacturer for kmcent2

Using compatible strings without the part for at24 is now deprecated. Use a correct 'atmel,' value. Signed-off-by: Bartosz Golaszewski --- arch/powerpc/boot/dts/fsl/kmcent2.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/boot/dts/fsl/kmcent2.dts b/arch/powe

[RESEND PATCH 3/3] powerpc: dts: use a correct at24 compatible fallback in ac14xx

Using 'at24' as fallback is now deprecated - use the full 'atmel,' string. Signed-off-by: Bartosz Golaszewski --- arch/powerpc/boot/dts/ac14xx.dts | 20 ++-- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/boot/dts/ac14xx.dts b/arch/powerpc/boot/dts/a

[RESEND PATCH 1/3] powerpc: dts: use 'atmel' as at24 anufacturer for pdm360ng

Using 'at' as the part of the compatible string is now deprecated. Use a correct string: 'atmel,'. Signed-off-by: Bartosz Golaszewski --- arch/powerpc/boot/dts/pdm360ng.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/boot/dts/pdm360ng.dts b/arch/powerpc/boo

Re: powerpc/64s: Default l1d_size to 64K in RFI fallback flush

On Tue, 2018-04-17 at 01:49:20 UTC, Michael Ellerman wrote: > From: Madhavan Srinivasan > > If there is no d-cache-size property in the device tree, l1d_size could > be zero. We don't actually expect that to happen, it's only been seen > on mambo (simulator) in some configurations. > > A zero-si

Re: [1/5] powerpc/lib: Fix off-by-one in alternate feature patching

On Mon, 2018-04-16 at 14:39:01 UTC, Michael Ellerman wrote: > When we patch an alternate feature section, we have to adjust any > relative branches that branch out of the alternate section. > > But currently we have a bug if we have a branch that points to past > the last instruction of the altern

[PATCH 0/6 v2] Support for fsl-mc bus and its devices in SMMU

This patchset defines IOMMU DT binding for fsl-mc bus and adds support in SMMU for fsl-mc bus. This patch series is dependent on patset: https://patchwork.kernel.org/patch/10317337/ These patches - Define property 'iommu-map' for fsl-mc bus (patch 1) - Integrates the fsl-mc bus with the SMMU

[PATCH 1/6 v2] Docs: dt: add fsl-mc iommu-map device-tree binding

The existing IOMMU bindings cannot be used to specify the relationship between fsl-mc devices and IOMMUs. This patch adds a generic binding for mapping fsl-mc devices to IOMMUs, using iommu-map property. Signed-off-by: Nipun Gupta --- .../devicetree/bindings/misc/fsl,qoriq-mc.txt | 39 +

[PATCH 2/6 v2] iommu: of: make of_pci_map_rid() available for other devices too

iommu-map property is also used by devices with fsl-mc. This patch moves the of_pci_map_rid to generic location, so that it can be used by other busses too. Signed-off-by: Nipun Gupta --- drivers/iommu/of_iommu.c | 106 +-- drivers/of/irq.c |

[PATCH 3/6 v2] iommu: support iommu configuration for fsl-mc devices

Signed-off-by: Nipun Gupta --- drivers/iommu/of_iommu.c | 20 1 file changed, 20 insertions(+) diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 4e7712f..af4fc3b 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -24,6 +24,7 @@ #inc

[PATCH 4/6 v2] iommu: arm-smmu: Add support for the fsl-mc bus

Implement bus specific support for the fsl-mc bus including registering arm_smmu_ops and bus specific device add operations. Signed-off-by: Nipun Gupta --- drivers/iommu/arm-smmu.c | 7 +++ drivers/iommu/iommu.c| 21 + include/linux/fsl/mc.h | 8 include/

[PATCH 5/6 v2] bus: fsl-mc: supoprt dma configure for devices on fsl-mc bus

Signed-off-by: Nipun Gupta --- drivers/bus/fsl-mc/fsl-mc-bus.c | 16 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c index 5d8266c..624828b 100644 --- a/drivers/bus/fsl-mc/fsl-mc-bus.c +++ b/drivers/

[PATCH 6/6 v2] arm64: dts: ls208xa: comply with the iommu map binding for fsl_mc

Fsl-mc bus now support the iommu-map property. Comply to this binding for fsl_mc bus. This patch also updates the dts w.r.t. the DMA configuration. Signed-off-by: Nipun Gupta --- arch/arm64/boot/dts/freescale/fsl-ls208xa.dtsi | 6 +- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git

[PATCH] powerpc: Allow selection of CONFIG_LD_DEAD_CODE_DATA_ELIMINATION

This option does dead code and data elimination with the linker by compiling with -ffunction-sections -fdata-sections and linking with --gc-sections. By selecting this option on mpc885_ads_defconfig, vmlinux LOAD segment size gets reduced by 10% Program Header before the patch: LOAD off0x

[PATCH] powerpc/misc: merge reloc_offset() and add_reloc_offset()

reloc_offset() is the same as add_reloc_offset(0) Signed-off-by: Christophe Leroy --- arch/powerpc/kernel/misc.S | 17 +++-- 1 file changed, 3 insertions(+), 14 deletions(-) diff --git a/arch/powerpc/kernel/misc.S b/arch/powerpc/kernel/misc.S index 384357cb8bc0..e1f3a5d054c4 100644

[PATCH] powerpc/boot: remove unused variable in mpc8xx

Variable div is set but never used. Remove it. Signed-off-by: Christophe Leroy --- arch/powerpc/boot/mpc8xx.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/powerpc/boot/mpc8xx.c b/arch/powerpc/boot/mpc8xx.c index add55a7f184f..c9bd9285c548 100644 --- a/arch/powerpc/b

[PATCH] powerpc/8xx: Remove RTC clock on 88x

The 885 familly processors don't have the Real Time Clock Signed-off-by: Christophe Leroy --- arch/powerpc/platforms/8xx/adder875.c| 2 -- arch/powerpc/platforms/8xx/ep88xc.c | 2 -- arch/powerpc/platforms/8xx/mpc885ads_setup.c | 2 -- 3 files changed, 6 deletions(-) diff --git

Re: [PATCH] powerpc/8xx: Build fix with Hugetlbfs enabled

Le 16/04/2018 à 13:27, Aneesh Kumar K.V a écrit : 8xx use slice code when hugetlbfs is enabled. We missed a header include on 8xx which resulted in the below build failure. config: mpc885_ads_defconfig + CONFIG_HUGETLBFS CC arch/powerpc/mm/slice.o arch/powerpc/mm/slice.c: In function

[PATCH] powerpc/time: remove to_tm and use RTC_LIB

RTC_LIB includes a generic function to convert RTC data into struct rtc_time. Use it and remove to_tm(). Signed-off-by: Christophe Leroy --- arch/powerpc/Kconfig| 1 + arch/powerpc/include/asm/time.h | 1 - arch/powerpc/kernel/rtas-proc.c | 4 +-- arch/powe

Re: [RFC PATCH 1/3] signal: Ensure every siginfo we send has all bits initialized

On Sun, Apr 15, 2018 at 10:57:33AM -0500, Eric W. Biederman wrote: > > Call clear_siginfo to ensure every stack allocated siginfo is properly > initialized before being passed to the signal sending functions. > > Note: It is not safe to depend on C initializers to initialize struct > siginfo on t

[PATCH v10 00/25] Speculative page faults

This is a port on kernel 4.16 of the work done by Peter Zijlstra to handle page fault without holding the mm semaphore [1]. The idea is to try to handle user space page faults without holding the mmap_sem. This should allow better concurrency for massively threaded process since the page fault han

[PATCH v10 01/25] mm: introduce CONFIG_SPECULATIVE_PAGE_FAULT

This configuration variable will be used to build the code needed to handle speculative page fault. By default it is turned off, and activated depending on architecture support, SMP and MMU. Suggested-by: Thomas Gleixner Suggested-by: David Rientjes Signed-off-by: Laurent Dufour --- mm/Kconfi

[PATCH v10 02/25] x86/mm: define ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT

Set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT which turns on the Speculative Page Fault handler when building for 64bit. Cc: Thomas Gleixner Signed-off-by: Laurent Dufour --- arch/x86/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d8983df5a2bc..

[PATCH v10 03/25] powerpc/mm: set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT

Set ARCH_SUPPORTS_SPECULATIVE_PAGE_FAULT for BOOK3S_64. This enables the Speculative Page Fault handler. Support is only provide for BOOK3S_64 currently because: - require CONFIG_PPC_STD_MMU because checks done in set_access_flags_filter() - require BOOK3S because we can't support for book3e_hug

[PATCH v10 04/25] mm: prepare for FAULT_FLAG_SPECULATIVE

From: Peter Zijlstra When speculating faults (without holding mmap_sem) we need to validate that the vma against which we loaded pages is still valid when we're ready to install the new PTE. Therefore, replace the pte_offset_map_lock() calls that (re)take the PTL with pte_map_lock() which can fa

[PATCH v10 05/25] mm: introduce pte_spinlock for FAULT_FLAG_SPECULATIVE

When handling page fault without holding the mmap_sem the fetch of the pte lock pointer and the locking will have to be done while ensuring that the VMA is not touched in our back. So move the fetch and locking operations in a dedicated function. Signed-off-by: Laurent Dufour --- mm/memory.c |

[PATCH v10 06/25] mm: make pte_unmap_same compatible with SPF

pte_unmap_same() is making the assumption that the page table are still around because the mmap_sem is held. This is no more the case when running a speculative page fault and additional check must be made to ensure that the final page table are still there. This is now done by calling pte_spinloc

[PATCH v10 07/25] mm: introduce INIT_VMA()

Some VMA struct fields need to be initialized once the VMA structure is allocated. Currently this only concerns anon_vma_chain field but some other will be added to support the speculative page fault. Instead of spreading the initialization calls all over the code, let's introduce a dedicated inli

[PATCH v10 08/25] mm: VMA sequence count

From: Peter Zijlstra Wrap the VMA modifications (vma_adjust/unmap_page_range) with sequence counts such that we can easily test if a VMA is changed. The unmap_page_range() one allows us to make assumptions about page-tables; when we find the seqcount hasn't changed we can assume page-tables are

[PATCH v10 09/25] mm: protect VMA modifications using VMA sequence count

The VMA sequence count has been introduced to allow fast detection of VMA modification when running a page fault handler without holding the mmap_sem. This patch provides protection against the VMA modification done in : - madvise() - mpol_rebind_policy() - vma_replace_poli

[PATCH v10 10/25] mm: protect mremap() against SPF hanlder

If a thread is remapping an area while another one is faulting on the destination area, the SPF handler may fetch the vma from the RB tree before the pte has been moved by the other thread. This means that the moved ptes will overwrite those create by the page fault handler leading to page leaked.

[PATCH v10 11/25] mm: protect SPF handler against anon_vma changes

The speculative page fault handler must be protected against anon_vma changes. This is because page_add_new_anon_rmap() is called during the speculative path. In addition, don't try speculative page fault if the VMA don't have an anon_vma structure allocated because its allocation should be protec

[PATCH v10 12/25] mm: cache some VMA fields in the vm_fault structure

When handling speculative page fault, the vma->vm_flags and vma->vm_page_prot fields are read once the page table lock is released. So there is no more guarantee that these fields would not change in our back. They will be saved in the vm_fault structure before the VMA is checked for changes. This

[PATCH v10 13/25] mm/migrate: Pass vm_fault pointer to migrate_misplaced_page()

migrate_misplaced_page() is only called during the page fault handling so it's better to pass the pointer to the struct vm_fault instead of the vma. This way during the speculative page fault path the saved vma->vm_flags could be used. Acked-by: David Rientjes Signed-off-by: Laurent Dufour ---

[PATCH v10 14/25] mm: introduce __lru_cache_add_active_or_unevictable

The speculative page fault handler which is run without holding the mmap_sem is calling lru_cache_add_active_or_unevictable() but the vm_flags is not guaranteed to remain constant. Introducing __lru_cache_add_active_or_unevictable() which has the vma flags value parameter instead of the vma pointer

[PATCH v10 15/25] mm: introduce __vm_normal_page()

When dealing with the speculative fault path we should use the VMA's field cached value stored in the vm_fault structure. Currently vm_normal_page() is using the pointer to the VMA to fetch the vm_flags value. This patch provides a new __vm_normal_page() which is receiving the vm_flags flags value

[PATCH v10 16/25] mm: introduce __page_add_new_anon_rmap()

When dealing with speculative page fault handler, we may race with VMA being split or merged. In this case the vma->vm_start and vm->vm_end fields may not match the address the page fault is occurring. This can only happens when the VMA is split but in that case, the anon_vma pointer of the new VM

[PATCH v10 17/25] mm: protect mm_rb tree with a rwlock

This change is inspired by the Peter's proposal patch [1] which was protecting the VMA using SRCU. Unfortunately, SRCU is not scaling well in that particular case, and it is introducing major performance degradation due to excessive scheduling operations. To allow access to the mm_rb tree without

[PATCH v10 18/25] mm: provide speculative fault infrastructure

From: Peter Zijlstra Provide infrastructure to do a speculative fault (not holding mmap_sem). The not holding of mmap_sem means we can race against VMA change/removal and page-table destruction. We use the SRCU VMA freeing to keep the VMA around. We use the VMA seqcount to detect change (includi

[PATCH v10 19/25] mm: adding speculative page fault failure trace events

This patch a set of new trace events to collect the speculative page fault event failures. Signed-off-by: Laurent Dufour --- include/trace/events/pagefault.h | 88 mm/memory.c | 62 ++-- 2 files changed, 137 in

[PATCH v10 20/25] perf: add a speculative page fault sw event

Add a new software event to count succeeded speculative page faults. Acked-by: David Rientjes Signed-off-by: Laurent Dufour --- include/uapi/linux/perf_event.h | 1 + 1 file changed, 1 insertion(+) diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index 912b85b5234

[PATCH v10 21/25] perf tools: add support for the SPF perf event

Add support for the new speculative faults event. Acked-by: David Rientjes Signed-off-by: Laurent Dufour --- tools/include/uapi/linux/perf_event.h | 1 + tools/perf/util/evsel.c | 1 + tools/perf/util/parse-events.c| 4 tools/perf/util/parse-events.l| 1 + too

[PATCH v10 23/25] mm: add speculative page fault vmstats

Add speculative_pgfault vmstat counter to count successful speculative page fault handling. Also fixing a minor typo in include/linux/vm_event_item.h. Signed-off-by: Laurent Dufour --- include/linux/vm_event_item.h | 3 +++ mm/memory.c | 1 + mm/vmstat.c | 5

[PATCH v10 24/25] x86/mm: add speculative pagefault handling

From: Peter Zijlstra Try a speculative fault before acquiring mmap_sem, if it returns with VM_FAULT_RETRY continue with the mmap_sem acquisition and do the traditional fault. Signed-off-by: Peter Zijlstra (Intel) [Clearing of FAULT_FLAG_ALLOW_RETRY is now done in handle_speculative_fault()] [

[PATCH v10 25/25] powerpc/mm: add speculative page fault

This patch enable the speculative page fault on the PowerPC architecture. This will try a speculative page fault without holding the mmap_sem, if it returns with VM_FAULT_RETRY, the mmap_sem is acquired and the traditional page fault processing is done. The speculative path is only tried for mult

[PATCH v10 22/25] mm: speculative page fault handler return VMA

When the speculative page fault handler is returning VM_RETRY, there is a chance that VMA fetched without grabbing the mmap_sem can be reused by the legacy page fault handler. By reusing it, we avoid calling find_vma() again. To achieve, that we must ensure that the VMA structure will not be freed

Re: powerpc/modules: Fix crashes by adding CONFIG_RELOCATABLE to vermagic

On 16 April 2018 at 16:10, Michael Ellerman wrote: > Ard Biesheuvel writes: > >> On 11 April 2018 at 16:49, Michael Ellerman >> wrote: >>> On Tue, 2018-04-10 at 01:22:06 UTC, Michael Ellerman wrote: If you build the kernel with CONFIG_RELOCATABLE=n, then install the modules, rebuild th

Re: [PATCH] powerpc: Allow selection of CONFIG_LD_DEAD_CODE_DATA_ELIMINATION

On Tue, Apr 17, 2018 at 12:49 PM, Christophe Leroy wrote: > This option does dead code and data elimination with the linker by > compiling with -ffunction-sections -fdata-sections and linking with > --gc-sections. > > By selecting this option on mpc885_ads_defconfig, > vmlinux LOAD segment size ge

Re: [PATCH] powerpc: Allow selection of CONFIG_LD_DEAD_CODE_DATA_ELIMINATION

Le 17/04/2018 à 18:45, Mathieu Malaterre a écrit : On Tue, Apr 17, 2018 at 12:49 PM, Christophe Leroy wrote: This option does dead code and data elimination with the linker by compiling with -ffunction-sections -fdata-sections and linking with --gc-sections. By selecting this option on mpc88

Re: [PATCH 2/6 v2] iommu: of: make of_pci_map_rid() available for other devices too

On 17/04/18 11:21, Nipun Gupta wrote: iommu-map property is also used by devices with fsl-mc. This patch moves the of_pci_map_rid to generic location, so that it can be used by other busses too. Signed-off-by: Nipun Gupta --- drivers/iommu/of_iommu.c | 106

[PATCH v2 1/2] powerpc: avoid an unnecessary test and branch in longjmp()

Doing the test at exit of the function avoids an unnecessary test and branch inside longjmp() Signed-off-by: Christophe Leroy --- v2: Swapped both patches in the serie to reduce number of impacted lines arch/powerpc/kernel/misc.S | 9 - 1 file changed, 4 insertions(+), 5 deletions(-)

[PATCH v2 2/2] powerpc/32be: use stmw/lmw for registers save/restore in asm

arch/powerpc/Makefile activates -mmultiple on BE PPC32 configs in order to use multiple word instructions in functions entry/exit The patch does the same for the asm parts, for consistency On processors like the 8xx on which insn fetching is pretty slow, this speeds up registers save/restore Sig

Re: [PATCH] powerpc: Allow selection of CONFIG_LD_DEAD_CODE_DATA_ELIMINATION

On Tue, Apr 17, 2018 at 6:49 PM, Christophe LEROY wrote: > > > Le 17/04/2018 à 18:45, Mathieu Malaterre a écrit : >> >> On Tue, Apr 17, 2018 at 12:49 PM, Christophe Leroy >> wrote: >>> >>> This option does dead code and data elimination with the linker by >>> compiling with -ffunction-sections -f

Re: [RFC PATCH 1/3] signal: Ensure every siginfo we send has all bits initialized

Dave Martin writes: > Hmmm > > memset()/clear_siginfo() may ensure that there are no uninitialised > explicit fields except for those in inactive union members, but I'm not > sure that this approach is guaranteed to sanitise the padding seen by > userspace. > > Rationale below, though it's a bit

Re: [PATCH] powerpc: platform: cell: spufs: Change return type to vm_fault_t

On Tue, Apr 17, 2018 at 9:20 PM, Souptick Joarder wrote: > Use new return type vm_fault_t for fault handler. For > now, this is just documenting that the function returns > a VM_FAULT value rather than an errno. Once all instances > are converted, vm_fault_t will become a distinct type. > > Refere

Re: [PATCH] powerpc: platform: cell: spufs: Change return type to vm_fault_t

On Wed, Apr 18, 2018 at 12:50:38AM +0530, Souptick Joarder wrote: > Use new return type vm_fault_t for fault handler. For > now, this is just documenting that the function returns > a VM_FAULT value rather than an errno. Once all instances > are converted, vm_fault_t will become a distinct type. >

Re: [PATCH 2/2] powernv/npu: Add a debugfs setting to change ATSD threshold

On Tue, 17 Apr 2018 19:11:29 +1000 Alistair Popple wrote: > The threshold at which it becomes more efficient to coalesce a range of > ATSDs into a single per-PID ATSD is currently not well understood due to a > lack of real-world work loads. This patch adds a debugfs parameter allowing > the thre

[PATCH] misc: cxl: Change return type to vm_fault_t

Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Reference id -> 1c8f422059ae ("mm: change return type to vm_fault_t") prev

[PATCH] powerpc: platform: cell: spufs: Change return type to vm_fault_t

Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Reference id -> 1c8f422059ae ("mm: change return type to vm_fault_t") Prev

Re: [PATCH 1/2] powernv/npu: Do a PID GPU TLB flush when invalidating a large address range

On Tue, Apr 17, 2018 at 7:17 PM, Balbir Singh wrote: > On Tue, Apr 17, 2018 at 7:11 PM, Alistair Popple > wrote: >> The NPU has a limited number of address translation shootdown (ATSD) >> registers and the GPU has limited bandwidth to process ATSDs. This can >> result in contention of ATSD regis

Re: [PATCH V1 00/11] powerpc/mm/book3s64: Support for split pmd ptlock

On Mon, 16 Apr 2018 16:57:12 +0530 "Aneesh Kumar K.V" wrote: > This patch series add split pmd pagetable lock for book3s64. nohash64 also > should > be able to switch to this. I need to workout the code dependency. This series > also migh have broken the build on platforms otherthan book3s64. I

Re: [PATCH] misc: cxl: Change return type to vm_fault_t

On 18/04/18 00:53, Souptick Joarder wrote: Use new return type vm_fault_t for fault handler. For now, this is just documenting that the function returns a VM_FAULT value rather than an errno. Once all instances are converted, vm_fault_t will become a distinct type. Reference id -> 1c8f422059ae (

[PATCH v2 2/7] powerpc: Use TIDR CPU feature to control TIDR allocation

From: Alastair D'Silva Switch the use of TIDR on it's CPU feature, rather than assuming it is available based on architecture. Signed-off-by: Alastair D'Silva --- arch/powerpc/kernel/process.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/process

[PATCH v2 4/7] ocxl: Rename pnv_ocxl_spa_remove_pe to clarify it's action

From: Alastair D'Silva The function removes the process element from NPU cache. Signed-off-by: Alastair D'Silva --- arch/powerpc/include/asm/pnv-ocxl.h | 2 +- arch/powerpc/platforms/powernv/ocxl.c | 4 ++-- drivers/misc/ocxl/link.c | 2 +- 3 files changed, 4 insertions(+), 4 de

[PATCH v2 0/7] ocxl: Implement Power9 as_notify/wait for OpenCAPI

From: Alastair D'Silva The Power 9 as_notify/wait feature provides a lower latency way to signal a thread that work is complete. This series enables the use of this feature from OpenCAPI adapters, as well as addressing a potential starvation issue when allocating thread IDs. Changelog: v2: Ren

[PATCH v2 3/7] powerpc: use task_pid_nr() for TID allocation

From: Alastair D'Silva The current implementation of TID allocation, using a global IDR, may result in an errant process starving the system of available TIDs. Instead, use task_pid_nr(), as mentioned by the original author. The scenario described which prevented it's use is not applicable, as se

[PATCH v2 5/7] ocxl: Expose the thread_id needed for wait on p9

From: Alastair D'Silva In order to successfully issue as_notify, an AFU needs to know the TID to notify, which in turn means that this information should be available in userspace so it can be communicated to the AFU. Signed-off-by: Alastair D'Silva --- drivers/misc/ocxl/context.c | 5 +

[PATCH v2 6/7] ocxl: Add an IOCTL so userspace knows what CPU features are available

From: Alastair D'Silva In order for a userspace AFU driver to call the Power9 specific OCXL_IOCTL_ENABLE_P9_WAIT, it needs to verify that it can actually make that call. Signed-off-by: Alastair D'Silva --- Documentation/accelerators/ocxl.rst | 1 - drivers/misc/ocxl/file.c| 25 +++

[PATCH v2 1/7] powerpc: Add TIDR CPU feature for Power9

From: Alastair D'Silva This patch adds a CPU feature bit to show whether the CPU has the TIDR register available, enabling as_notify/wait in userspace. Signed-off-by: Alastair D'Silva --- arch/powerpc/include/asm/cputable.h | 3 ++- arch/powerpc/kernel/dt_cpu_ftrs.c | 1 + 2 files changed, 3

[PATCH v2 7/7] ocxl: Document new OCXL IOCTLs

From: Alastair D'Silva Signed-off-by: Alastair D'Silva --- Documentation/accelerators/ocxl.rst | 11 +++ 1 file changed, 11 insertions(+) diff --git a/Documentation/accelerators/ocxl.rst b/Documentation/accelerators/ocxl.rst index 7904adcc07fd..3b8d3b99795c 100644 --- a/Documentation/

Re: [RFC] virtio: Use DMA MAP API for devices without an IOMMU

On 04/15/2018 05:41 PM, Christoph Hellwig wrote: > On Fri, Apr 06, 2018 at 06:37:18PM +1000, Benjamin Herrenschmidt wrote: implemented as DMA API which the virtio core understands. There is no need for an IOMMU to be involved for the device representation in this case IMHO. >>> >>> T

Re: [PATCH] powerpc/8xx: Build fix with Hugetlbfs enabled

"Aneesh Kumar K.V" writes: > 8xx use slice code when hugetlbfs is enabled. We missed a header include on > 8xx which resulted in the below build failure. > > config: mpc885_ads_defconfig + CONFIG_HUGETLBFS > >CC arch/powerpc/mm/slice.o > arch/powerpc/mm/slice.c: In function 'slice_get_un

RE: [PATCH 2/6 v2] iommu: of: make of_pci_map_rid() available for other devices too

> -Original Message- > From: Robin Murphy [mailto:robin.mur...@arm.com] > Sent: Tuesday, April 17, 2018 10:23 PM > To: Nipun Gupta ; robh...@kernel.org; > frowand.l...@gmail.com > Cc: will.dea...@arm.com; mark.rutl...@arm.com; catalin.mari...@arm.com; > h...@lst.de; gre...@linuxfoundation

Re: [PATCH] powerpc: Allow selection of CONFIG_LD_DEAD_CODE_DATA_ELIMINATION

Le 17/04/2018 à 19:10, Mathieu Malaterre a écrit : On Tue, Apr 17, 2018 at 6:49 PM, Christophe LEROY wrote: Le 17/04/2018 à 18:45, Mathieu Malaterre a écrit : On Tue, Apr 17, 2018 at 12:49 PM, Christophe Leroy wrote: This option does dead code and data elimination with the linker by co