From patchwork Mon Feb 12 18:12:28 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 872255 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3zgDWK6hLFz9s7h for ; Tue, 13 Feb 2018 05:21:01 +1100 (AEDT) Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 3zgDWK58gvzF0bg for ; Tue, 13 Feb 2018 05:21:01 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=c-s.fr (client-ip=93.17.236.30; helo=pegase1.c-s.fr; envelope-from=christophe.leroy@c-s.fr; receiver=) Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3zgDKW72MNzF0r8 for ; Tue, 13 Feb 2018 05:12:31 +1100 (AEDT) Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 3zgDKL4s3tz9tvMx; Mon, 12 Feb 2018 19:12:22 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id z8BRrVMpsJH1; Mon, 12 Feb 2018 19:12:22 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase1.c-s.fr (Postfix) with ESMTP id 3zgDKL4KB9z9tvMh; Mon, 12 Feb 2018 19:12:22 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id E96B78B96C; Mon, 12 Feb 2018 19:12:28 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id xYbeuPKjHPS1; Mon, 12 Feb 2018 19:12:28 +0100 (CET) Received: from po15720vm.idsi0.si.c-s.fr (unknown [192.168.232.3]) by messagerie.si.c-s.fr (Postfix) with ESMTP id A31D88B962; Mon, 12 Feb 2018 19:12:28 +0100 (CET) Received: by po15720vm.idsi0.si.c-s.fr (Postfix, from userid 0) id 7C1AD67B0B; Mon, 12 Feb 2018 19:12:28 +0100 (CET) Message-Id: <6a8c9183257dfcfeb1d8ed1ecc778ec3da19dcd4.1518382747.git.christophe.leroy@c-s.fr> In-Reply-To: <02a62db83282b5ef3e0e8281fdc46fa91beffc86.1518382747.git.christophe.leroy@c-s.fr> References: <02a62db83282b5ef3e0e8281fdc46fa91beffc86.1518382747.git.christophe.leroy@c-s.fr> From: Christophe Leroy Subject: [RFC REBASED 4/5] powerpc/mm/slice: Use const pointers to cached slice masks where possible To: Nicholas Piggin Date: Mon, 12 Feb 2018 19:12:28 +0100 (CET) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" The slice_mask cache was a basic conversion which copied the slice mask into caller's structures, because that's how the original code worked. In most cases the pointer can be used directly instead, saving a copy and an on-stack structure. This also converts the slice_mask bit operation helpers to be the usual 3-operand kind, which is clearer to work with. And we remove some unnecessary intermediate bitmaps, reducing stack and copy overhead further. Signed-off-by: Nicholas Piggin Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/book3s/64/slice.h | 7 +++ arch/powerpc/include/asm/nohash/32/slice.h | 6 +++ arch/powerpc/mm/slice.c | 77 ++++++++++++++++++------------ 3 files changed, 59 insertions(+), 31 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/slice.h b/arch/powerpc/include/asm/book3s/64/slice.h index f9a2c8bd7a77..be1ce8e91ad1 100644 --- a/arch/powerpc/include/asm/book3s/64/slice.h +++ b/arch/powerpc/include/asm/book3s/64/slice.h @@ -63,6 +63,13 @@ static inline void slice_bitmap_set(unsigned long *map, unsigned int start, { bitmap_set(map, start, nbits); } + +static inline void slice_bitmap_copy(unsigned long *dst, + const unsigned long *src, + unsigned int nbits) +{ + bitmap_copy(dst, src, nbits); +} #endif /* __ASSEMBLY__ */ #else /* CONFIG_PPC_MM_SLICES */ diff --git a/arch/powerpc/include/asm/nohash/32/slice.h b/arch/powerpc/include/asm/nohash/32/slice.h index bcb4924f7d22..38f041e01a0a 100644 --- a/arch/powerpc/include/asm/nohash/32/slice.h +++ b/arch/powerpc/include/asm/nohash/32/slice.h @@ -58,6 +58,12 @@ static inline void slice_bitmap_set(unsigned long *map, unsigned int start, unsigned int nbits) { } + +static inline void slice_bitmap_copy(unsigned long *dst, + const unsigned long *src, + unsigned int nbits) +{ +} #endif /* __ASSEMBLY__ */ #endif /* CONFIG_PPC_MM_SLICES */ diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c index 311168ca3939..b8b691369c29 100644 --- a/arch/powerpc/mm/slice.c +++ b/arch/powerpc/mm/slice.c @@ -468,21 +468,30 @@ static unsigned long slice_find_area(struct mm_struct *mm, unsigned long len, return slice_find_area_bottomup(mm, len, mask, psize, high_limit); } -static inline void slice_or_mask(struct slice_mask *dst, +static inline void slice_copy_mask(struct slice_mask *dst, const struct slice_mask *src) { - dst->low_slices |= src->low_slices; - slice_bitmap_or(dst->high_slices, dst->high_slices, src->high_slices, + dst->low_slices = src->low_slices; + slice_bitmap_copy(dst->high_slices, src->high_slices, SLICE_NUM_HIGH); +} + +static inline void slice_or_mask(struct slice_mask *dst, + const struct slice_mask *src1, + const struct slice_mask *src2) +{ + dst->low_slices = src1->low_slices | src2->low_slices; + slice_bitmap_or(dst->high_slices, src1->high_slices, src2->high_slices, SLICE_NUM_HIGH); } static inline void slice_andnot_mask(struct slice_mask *dst, - const struct slice_mask *src) + const struct slice_mask *src1, + const struct slice_mask *src2) { - dst->low_slices &= ~src->low_slices; + dst->low_slices = src1->low_slices & ~src2->low_slices; - slice_bitmap_andnot(dst->high_slices, dst->high_slices, - src->high_slices, SLICE_NUM_HIGH); + slice_bitmap_andnot(dst->high_slices, src1->high_slices, + src2->high_slices, SLICE_NUM_HIGH); } #ifdef CONFIG_PPC_64K_PAGES @@ -495,10 +504,10 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, unsigned long flags, unsigned int psize, int topdown) { - struct slice_mask mask; struct slice_mask good_mask; struct slice_mask potential_mask; - struct slice_mask compat_mask; + const struct slice_mask *maskp; + const struct slice_mask *compat_maskp = NULL; int fixed = (flags & MAP_FIXED); int pshift = max_t(int, mmu_psize_defs[psize].shift, PAGE_SHIFT); unsigned long page_size = 1UL << pshift; @@ -537,9 +546,6 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, potential_mask.low_slices = 0; slice_bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH); - compat_mask.low_slices = 0; - slice_bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH); - /* Sanity checks */ BUG_ON(mm->task_size == 0); BUG_ON(mm->context.slb_addr_limit == 0); @@ -562,7 +568,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, /* First make up a "good" mask of slices that have the right size * already */ - good_mask = *slice_mask_for_size(mm, psize); + maskp = slice_mask_for_size(mm, psize); slice_print_mask(" good_mask", &good_mask); /* @@ -587,11 +593,16 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, #ifdef CONFIG_PPC_64K_PAGES /* If we support combo pages, we can allow 64k pages in 4k slices */ if (psize == MMU_PAGE_64K) { - compat_mask = *slice_mask_for_size(mm, MMU_PAGE_4K); + compat_maskp = slice_mask_for_size(mm, MMU_PAGE_4K); if (fixed) - slice_or_mask(&good_mask, &compat_mask); - } + slice_or_mask(&good_mask, maskp, compat_maskp); + else + slice_copy_mask(&good_mask, maskp); + } else #endif + { + slice_copy_mask(&good_mask, maskp); + } /* First check hint if it's valid or if we have MAP_FIXED */ if (addr || fixed) { @@ -621,7 +632,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, * empty and thus can be converted */ slice_mask_for_free(mm, &potential_mask, high_limit); - slice_or_mask(&potential_mask, &good_mask); + slice_or_mask(&potential_mask, &potential_mask, &good_mask); slice_print_mask(" potential", &potential_mask); if (addr || fixed) { @@ -658,7 +669,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, #ifdef CONFIG_PPC_64K_PAGES if (addr == -ENOMEM && psize == MMU_PAGE_64K) { /* retry the search with 4k-page slices included */ - slice_or_mask(&potential_mask, &compat_mask); + slice_or_mask(&potential_mask, &potential_mask, compat_maskp); addr = slice_find_area(mm, len, &potential_mask, psize, topdown, high_limit); } @@ -667,16 +678,17 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, if (addr == -ENOMEM) return -ENOMEM; - slice_range_to_mask(addr, len, &mask); + slice_range_to_mask(addr, len, &potential_mask); slice_dbg(" found potential area at 0x%lx\n", addr); - slice_print_mask(" mask", &mask); + slice_print_mask(" mask", maskp); convert: - slice_andnot_mask(&mask, &good_mask); - slice_andnot_mask(&mask, &compat_mask); - if (mask.low_slices || - !slice_bitmap_empty(mask.high_slices, SLICE_NUM_HIGH)) { - slice_convert(mm, &mask, psize); + slice_andnot_mask(&potential_mask, &potential_mask, &good_mask); + if (compat_maskp && !fixed) + slice_andnot_mask(&potential_mask, &potential_mask, compat_maskp); + if (potential_mask.low_slices || + !slice_bitmap_empty(potential_mask.high_slices, SLICE_NUM_HIGH)) { + slice_convert(mm, &potential_mask, psize); if (psize > MMU_PAGE_BASE) on_each_cpu(slice_flush_segments, mm, 1); } @@ -834,19 +846,22 @@ void slice_set_range_psize(struct mm_struct *mm, unsigned long start, int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr, unsigned long len) { - struct slice_mask available; + const struct slice_mask *maskp; unsigned int psize = mm->context.user_psize; if (radix_enabled()) return 0; - available = *slice_mask_for_size(mm, psize); + maskp = slice_mask_for_size(mm, psize); #ifdef CONFIG_PPC_64K_PAGES /* We need to account for 4k slices too */ if (psize == MMU_PAGE_64K) { - struct slice_mask compat_mask; - compat_mask = *slice_mask_for_size(mm, MMU_PAGE_4K); - slice_or_mask(&available, &compat_mask); + const struct slice_mask *compat_maskp; + struct slice_mask available; + + compat_maskp = slice_mask_for_size(mm, MMU_PAGE_4K); + slice_or_mask(&available, maskp, compat_maskp); + return !slice_check_range_fits(mm, &available, addr, len); } #endif @@ -856,6 +871,6 @@ int is_hugepage_only_range(struct mm_struct *mm, unsigned long addr, slice_print_mask(" mask", &mask); slice_print_mask(" available", &available); #endif - return !slice_check_range_fits(mm, &available, addr, len); + return !slice_check_range_fits(mm, maskp, addr, len); } #endif