From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailhub1.si.c-s.fr (2.236.17.93.rev.sfr.net [93.17.236.2]) by lists.ozlabs.org (Postfix) with ESMTP id 4581F1A006B for ; Wed, 23 Sep 2015 02:50:31 +1000 (AEST) Message-Id: From: Christophe Leroy Subject: [PATCH v2 00/25] powerpc/8xx: Use large pages for RAM and IMMR and other improvments To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , scottwood@freescale.com Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Date: Tue, 22 Sep 2015 18:50:27 +0200 (CEST) List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The main purpose of this patchset is to dramatically reduce the time spent in DTLB miss handler. This is achieved by: 1/ Mapping RAM with 8M pages 2/ Mapping IMMR with a fixed 512K page On a live running system (VoIP gateway for Air Trafic Control), over a 10 minutes period (with 277s idle), we get 87 millions DTLB misses and approximatly 35 secondes are spent in DTLB handler. This represents 5.8% of the overall time and even 10.8% of the non-idle time. Among those 87 millions DTLB misses, 15% are on user addresses and 85% are on kernel addresses. And within the kernel addresses, 93% are on addresses from the linear address space and only 7% are on addresses from the virtual address space. Once the full patchset applied, the number of DTLB misses during the period is reduced to 11.8 millions for a duration of 5.8s, which represents 2% of the non-idle time. This patch also includes other miscellaneous improvements: 1/ Handling of CPU6 ERRATA directly in mtspr() C macro to reduce code specific to PPC8xx 2/ Rewrite of a few non critical ASM functions in C 3/ Removal of some unused items See related patches for details Christophe Leroy (25): powerpc/8xx: Save r3 all the time in DTLB miss handler powerpc/8xx: Map linear kernel RAM with 8M pages powerpc: Update documentation for noltlbs kernel parameter powerpc/8xx: move setup_initial_memory_limit() into 8xx_mmu.c powerpc/8xx: Fix vaddr for IMMR early remap powerpc32: iounmap() cannot vunmap() area mapped by TLBCAMs either powerpc32: refactor x_mapped_by_bats() and x_mapped_by_tlbcam() together powerpc/8xx: Map IMMR area with 512k page at a fixed address powerpc/8xx: show IMMR area in startup memory layout powerpc/8xx: CONFIG_PIN_TLB unneeded for CONFIG_PPC_EARLY_DEBUG_CPM powerpc/8xx: map 16M RAM at startup powerpc32: Remove useless/wrong MMU:setio progress message powerpc/8xx: also use r3 in the ITLB miss in all situations powerpc32: remove ioremap_base powerpc/8xx: move 8xx SPRN defines into reg_8xx.h and add some missing ones powerpc/8xx: Handle CPU6 ERRATA directly in mtspr() macro powerpc/8xx: remove special handling of CPU6 errata in set_dec() powerpc/8xx: rewrite set_context() in C powerpc/8xx: rewrite flush_instruction_cache() in C powerpc32: Remove clear_pages() and define clear_page() inline powerpc: add inline functions for cache related instructions powerpc32: move xxxxx_dcache_range() functions inline powerpc: Simplify test in __dma_sync() powerpc32: small optimisation in flush_icache_range() powerpc32: Remove one insn in mulhdu Documentation/kernel-parameters.txt | 2 +- arch/powerpc/Kconfig.debug | 2 - arch/powerpc/include/asm/cache.h | 19 +++ arch/powerpc/include/asm/cacheflush.h | 55 +++++++- arch/powerpc/include/asm/mmu-8xx.h | 26 ++-- arch/powerpc/include/asm/page_32.h | 17 ++- arch/powerpc/include/asm/pgtable-ppc32.h | 5 + arch/powerpc/include/asm/reg.h | 2 + arch/powerpc/include/asm/reg_8xx.h | 106 +++++++++++++++ arch/powerpc/include/asm/time.h | 6 +- arch/powerpc/kernel/head_8xx.S | 167 ++++++++++++------------ arch/powerpc/kernel/misc_32.S | 107 ++-------------- arch/powerpc/kernel/ppc_ksyms.c | 2 + arch/powerpc/kernel/ppc_ksyms_32.c | 1 - arch/powerpc/mm/8xx_mmu.c | 191 ++++++++++++++++++++++++++++ arch/powerpc/mm/Makefile | 1 + arch/powerpc/mm/dma-noncoherent.c | 2 +- arch/powerpc/mm/init_32.c | 23 ---- arch/powerpc/mm/mem.c | 4 + arch/powerpc/mm/mmu_decl.h | 16 +-- arch/powerpc/mm/pgtable_32.c | 54 +++++++- arch/powerpc/platforms/embedded6xx/mpc10x.h | 8 -- 22 files changed, 553 insertions(+), 263 deletions(-) create mode 100644 arch/powerpc/mm/8xx_mmu.c -- 2.1.0