Re: [PATCH V2 04/68] powerpc/mm: Use big endian page table for book3s 64

Hi, > This enables us to share the same page table code for > both radix and hash. Radix use a hardware defined big endian > page table This is measurably worse (a little over 2% on POWER8) on a futex microbenchmark: #define _GNU_SOURCE #include #include #include #define ITERATIONS 1000

[PATCH 1/3] powerpc: Avoid load hit store in __giveup_fpu() and __giveup_altivec()

From: Anton Blanchard In both __giveup_fpu() and __giveup_altivec() we make two modifications to tsk->thread.regs->msr. gcc decides to do a read/modify/write of each change, so we end up with a load hit store: ld r9,264(r10) rldicl r9,r9,50,1 rotldi r9,r9,14

[PATCH 2/3] powerpc: Avoid load hit store in setup_sigcontext()

From: Anton Blanchard In setup_sigcontext(), we set current->thread.vrsave then use it straight after. Since current is hidden from the compiler via inline assembly, it cannot optimise this and we end up with a load hit store. Fix this by using a temporary. Signed-off-by: Anton Blanchard ---

[PATCH 3/3] powerpc: Avoid load hit store when using find_linux_pte_or_hugepte()

From: Anton Blanchard In many cases we disable interrupts right before calling find_linux_pte_or_hugepte(). find_linux_pte_or_hugepte() first checks interrupts are disabled before calling __find_linux_pte_or_hugepte(): if (!arch_irqs_disabled()) { pr_info("%s called with

Re: [PATCH V2 04/68] powerpc/mm: Use big endian page table for book3s 64

On Sun, 2016-05-29 at 21:03 +1000, Anton Blanchard wrote: > Hi, > > > > > This enables us to share the same page table code for > > both radix and hash. Radix use a hardware defined big endian > > page table > This is measurably worse (a little over 2% on POWER8) on a futex > microbenchmark: Tha

Re: [PATCH 2/3] powerpc: Avoid load hit store in setup_sigcontext()

On Sun, 2016-05-29 at 22:03 +1000, Anton Blanchard wrote: > From: Anton Blanchard > > In setup_sigcontext(), we set current->thread.vrsave then use it > straight after. Since current is hidden from the compiler via inline > assembly, it cannot optimise this and we end up with a load hit store. I

Re: [PATCH 2/3] powerpc: Avoid load hit store in setup_sigcontext()

Hi, > On Sun, 2016-05-29 at 22:03 +1000, Anton Blanchard wrote: > > From: Anton Blanchard > > > > In setup_sigcontext(), we set current->thread.vrsave then use it > > straight after. Since current is hidden from the compiler via inline > > assembly, it cannot optimise this and we end up with a l

Re: [PATCH v3 00/16] genrtc removal

Hi, On 03/05/2016 at 12:05:34 +0200, Arnd Bergmann wrote : > On Tuesday 03 May 2016 09:24:18 Alexandre Belloni wrote: > > Hi Arnd, > > > > I see you didn't copy Greg on that series (that may explain his > > confusion on the previous patch), do you expect me to take it > > through the RTC tree? Th

Re: [PATCH V2 04/68] powerpc/mm: Use big endian page table for book3s 64

Hi Ben, > That is surprising, do we have any idea what specifically increases > the overhead so significantly ? Does gcc know about ldbrx/stdbrx ? I > notice in our io.h for example we still do manual ld/std + swap > because old processors didn't know these, we should fix that for > CONFIG_POWER8

Re: [PATCH V2 04/68] powerpc/mm: Use big endian page table for book3s 64

On Mon, 2016-05-30 at 09:08 +1000, Anton Blanchard via Linuxppc-dev wrote: > > That is surprising, do we have any idea what specifically increases > > the overhead so significantly ? Does gcc know about ldbrx/stdbrx ? I > > notice in our io.h for example we still do manual ld/std + swap > > because

Re: [PATCH 3/3] powerpc: Avoid load hit store when using find_linux_pte_or_hugepte()

Anton Blanchard writes: > From: Anton Blanchard > > In many cases we disable interrupts right before calling > find_linux_pte_or_hugepte(). > > find_linux_pte_or_hugepte() first checks interrupts are disabled > before calling __find_linux_pte_or_hugepte(): > > if (!arch_irqs_disabled())

[PATCH 1/5] powerpc/pseries: Drop support for MPIC in pseries

MPIC was only used by Power3 which is now unsupported, so drop support for MPIC. XICS is now the only supported interrupt controller for pSeries so make the XICS functions generic. Signed-off-by: Rashmica Gupta --- arch/powerpc/platforms/pseries/setup.c | 77 +++--- 1

[PATCH 2/5] powerpc/pseries: Remove MPIC from pseries smp

MPIC was only used by Power3 which is now unsupported, so remove MPIC code. XICS is now the only supported interrupt controller for pSeries so do some cleanups too. Signed-off-by: Rashmica Gupta --- arch/powerpc/platforms/pseries/pseries.h | 6 ++ arch/powerpc/platforms/pseries/setup.c |

[PATCH 3/5] powerpc/pseries: Remove MPIC from pseries kexec

MPIC was only used by Power3 which is now unsupported, so remove MPIC code. XICS is now the only supported interrupt controller for pSeries so do some cleanups too. Signed-off-by: Rashmica Gupta --- arch/powerpc/platforms/pseries/kexec.c | 23 +-- arch/powerpc/platforms/pse

[PATCH 4/5] powerpc/pseries: Remove MPIC from pseries cpu hotplug

MPIC was only used by Power3 which is now unsupported, so remove MPIC code. Signed-off-by: Rashmica Gupta --- arch/powerpc/platforms/pseries/hotplug-cpu.c | 13 - 1 file changed, 13 deletions(-) diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pser

[PATCH 5/5] powerpc/pseries: Remove MPIC from pseries event sources

MPIC was only used by Power3 which is now unsupported, so remove MPIC code. XICS is now the only supported interrupt controller for pSeries so do some cleanups too. Signed-off-by: Rashmica Gupta --- arch/powerpc/platforms/pseries/event_sources.c | 53 +++--- 1 file changed, 1