From patchwork Tue Mar 6 13:24:59 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Piggin X-Patchwork-Id: 882066 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [103.22.144.68]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3zwdCF0kNWz9sgW for ; Wed, 7 Mar 2018 00:38:32 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="jNdIjrVD"; dkim-atps=neutral Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 3zwdCC69b8zF13m for ; Wed, 7 Mar 2018 00:38:31 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="jNdIjrVD"; dkim-atps=neutral X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:400e:c01::243; helo=mail-pl0-x243.google.com; envelope-from=npiggin@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="jNdIjrVD"; dkim-atps=neutral Received: from mail-pl0-x243.google.com (mail-pl0-x243.google.com [IPv6:2607:f8b0:400e:c01::243]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3zwcwD28HxzF1Kh for ; Wed, 7 Mar 2018 00:25:32 +1100 (AEDT) Received: by mail-pl0-x243.google.com with SMTP id s13-v6so11824310plq.6 for ; Tue, 06 Mar 2018 05:25:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=XhjFmxXPeIdvxVNFYcrWKPvDVFoxaEk68gcjWAxRklk=; b=jNdIjrVDqmbI7hMeFQU0oV458gUWH5HfaGeN0syLgkufvYJKR10EnrIG8iCSKbKRat W+5VOVph34B1XcP1JBO56fG9OvmdQcgil7XdJ8YV2g0998RH423apWz3mxFwXpxanSrS Flh7SGeVUBSE3WOajEEit8slwqVXRtcqXplKbEG8lanCB0HlKREHuKXaBGAdhxSRfQiE ezXKuXqAN8mrlOESkwz+wC45jWHB3MnJaULxPMIrbxSdmSOS5t+kRGeeNAiXHxOY/dc8 PlRoSDgHyJn6YaMkPGn7c4yo0iGgm+a6hwXCFrydgLwg3rrZ2h8Dp326hTyHt5AErqT8 3nlg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=XhjFmxXPeIdvxVNFYcrWKPvDVFoxaEk68gcjWAxRklk=; b=mpRD+oj7JmmHdDaXc+OtlS3cNaOzWo30+wWtJtP2MmG0YvbXMYuMo7la97/f5AfE8U vMfBIQavQUErNPCRxXUKVav42xJ/EsnuPVFAgvWMeXV84PwBm5rR+JfbO+fSrUBPSoi6 7Ylni2odYsO6ldjfsCivp0+pFQs3cnQdtFCu46xztmkmZjSpR1eAANCY7uxoN4jqIUf3 cQtjGx2Uifark2h0IFZJLhUemyz4fhhrGla4W3obfmsQBvND0x7RVJ2iRP1Bj/zhki4e +JNBGw4XDebTMpZ+8HoJWILmAdnFHmy7wXxknEX78fO/5HKjT/TuZfEVxvfyc4jOYLg9 0lOQ== X-Gm-Message-State: APf1xPBIzSwWVNWmZoJePN6HIcD4/nHNxkNgdP1c61mBiBtyVwcV2XsD Hj/jbH+J8Ii1k9yswIk8s269PQ== X-Google-Smtp-Source: AG47ELtDa3Dp39ApzOGuoBBZRUftg0sypWwbaad0ZC815t6UyAcwoVEwn69Qs3c/fu7VgjkLYrRa4Q== X-Received: by 2002:a17:902:6e8c:: with SMTP id v12-v6mr16670914plk.424.1520342729615; Tue, 06 Mar 2018 05:25:29 -0800 (PST) Received: from roar.au.ibm.com (115-64-218-172.tpgi.com.au. [115.64.218.172]) by smtp.gmail.com with ESMTPSA id j64sm34369772pfe.68.2018.03.06.05.25.26 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 06 Mar 2018 05:25:28 -0800 (PST) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH 02/10] powerpc/mm/slice: Simplify and optimise slice context initialisation Date: Tue, 6 Mar 2018 23:24:59 +1000 Message-Id: <20180306132507.10649-3-npiggin@gmail.com> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180306132507.10649-1-npiggin@gmail.com> References: <20180306132507.10649-1-npiggin@gmail.com> 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: "Aneesh Kumar K . V" , Nicholas Piggin Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" The slice state of an mm gets zeroed then initialised upon exec. This is the only caller of slice_set_user_psize now, so that can be removed and instead implement a faster and simplified approach that requires no locking or checking existing state. This speeds up vfork+exec+exit performance on POWER8 by 3%. Signed-off-by: Nicholas Piggin --- arch/powerpc/include/asm/slice.h | 8 ++-- arch/powerpc/mm/mmu_context_book3s64.c | 9 +---- arch/powerpc/mm/mmu_context_nohash.c | 5 +-- arch/powerpc/mm/slice.c | 69 +++++++--------------------------- 4 files changed, 19 insertions(+), 72 deletions(-) diff --git a/arch/powerpc/include/asm/slice.h b/arch/powerpc/include/asm/slice.h index 172711fadb1c..e40406cf5628 100644 --- a/arch/powerpc/include/asm/slice.h +++ b/arch/powerpc/include/asm/slice.h @@ -28,15 +28,13 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr); -void slice_set_user_psize(struct mm_struct *mm, unsigned int psize); void slice_set_range_psize(struct mm_struct *mm, unsigned long start, unsigned long len, unsigned int psize); -#endif /* __ASSEMBLY__ */ -#else /* CONFIG_PPC_MM_SLICES */ +void slice_init_new_context_exec(struct mm_struct *mm); + +#endif /* __ASSEMBLY__ */ -#define slice_set_range_psize(mm, start, len, psize) \ - slice_set_user_psize((mm), (psize)) #endif /* CONFIG_PPC_MM_SLICES */ #endif /* _ASM_POWERPC_SLICE_H */ diff --git a/arch/powerpc/mm/mmu_context_book3s64.c b/arch/powerpc/mm/mmu_context_book3s64.c index 929d9ef7083f..80acad52b006 100644 --- a/arch/powerpc/mm/mmu_context_book3s64.c +++ b/arch/powerpc/mm/mmu_context_book3s64.c @@ -93,13 +93,6 @@ static int hash__init_new_context(struct mm_struct *mm) if (index < 0) return index; - /* - * In the case of exec, use the default limit, - * otherwise inherit it from the mm we are duplicating. - */ - if (!mm->context.slb_addr_limit) - mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64; - /* * The old code would re-promote on fork, we don't do that when using * slices as it could cause problem promoting slices that have been @@ -115,7 +108,7 @@ static int hash__init_new_context(struct mm_struct *mm) * check against 0 is OK. */ if (mm->context.id == 0) - slice_set_user_psize(mm, mmu_virtual_psize); + slice_init_new_context_exec(mm); subpage_prot_init_new_context(mm); diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c index d98f7e5c141b..be8f5c9d4d08 100644 --- a/arch/powerpc/mm/mmu_context_nohash.c +++ b/arch/powerpc/mm/mmu_context_nohash.c @@ -332,9 +332,6 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm) pr_hard("initing context for mm @%p\n", mm); #ifdef CONFIG_PPC_MM_SLICES - if (!mm->context.slb_addr_limit) - mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW; - /* * We have MMU_NO_CONTEXT set to be ~0. Hence check * explicitly against context.id == 0. This ensures that we properly @@ -343,7 +340,7 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm) * will have id != 0). */ if (mm->context.id == 0) - slice_set_user_psize(mm, mmu_virtual_psize); + slice_init_new_context_exec(mm); #endif mm->context.id = MMU_NO_CONTEXT; mm->context.active = 0; diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c index 5e9e1e57d580..af4351b15d01 100644 --- a/arch/powerpc/mm/slice.c +++ b/arch/powerpc/mm/slice.c @@ -671,70 +671,29 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr) } EXPORT_SYMBOL_GPL(get_slice_psize); -/* - * This is called by hash_page when it needs to do a lazy conversion of - * an address space from real 64K pages to combo 4K pages (typically - * when hitting a non cacheable mapping on a processor or hypervisor - * that won't allow them for 64K pages). - * - * This is also called in init_new_context() to change back the user - * psize from whatever the parent context had it set to - * N.B. This may be called before mm->context.id has been set. - * - * This function will only change the content of the {low,high)_slice_psize - * masks, it will not flush SLBs as this shall be handled lazily by the - * caller. - */ -void slice_set_user_psize(struct mm_struct *mm, unsigned int psize) +void slice_init_new_context_exec(struct mm_struct *mm) { - int index, mask_index; unsigned char *hpsizes, *lpsizes; - unsigned long flags; - unsigned int old_psize; - int i; - - slice_dbg("slice_set_user_psize(mm=%p, psize=%d)\n", mm, psize); - - VM_BUG_ON(radix_enabled()); - spin_lock_irqsave(&slice_convert_lock, flags); + unsigned int psize = mmu_virtual_psize; - old_psize = mm->context.user_psize; - slice_dbg(" old_psize=%d\n", old_psize); - if (old_psize == psize) - goto bail; + slice_dbg("slice_init_new_context_exec(mm=%p)\n", mm); + /* + * In the case of exec, use the default limit. In the + * case of fork it is just inherited from the mm being + * duplicated. + */ + mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64; mm->context.user_psize = psize; - wmb(); + /* + * Set all slice psizes to the default. + */ lpsizes = mm->context.low_slices_psize; - for (i = 0; i < SLICE_NUM_LOW; i++) { - mask_index = i & 0x1; - index = i >> 1; - if (((lpsizes[index] >> (mask_index * 4)) & 0xf) == old_psize) - lpsizes[index] = (lpsizes[index] & - ~(0xf << (mask_index * 4))) | - (((unsigned long)psize) << (mask_index * 4)); - } + memset(lpsizes, (psize << 4) | psize, SLICE_NUM_LOW >> 1); hpsizes = mm->context.high_slices_psize; - for (i = 0; i < SLICE_NUM_HIGH; i++) { - mask_index = i & 0x1; - index = i >> 1; - if (((hpsizes[index] >> (mask_index * 4)) & 0xf) == old_psize) - hpsizes[index] = (hpsizes[index] & - ~(0xf << (mask_index * 4))) | - (((unsigned long)psize) << (mask_index * 4)); - } - - - - - slice_dbg(" lsps=%lx, hsps=%lx\n", - (unsigned long)mm->context.low_slices_psize, - (unsigned long)mm->context.high_slices_psize); - - bail: - spin_unlock_irqrestore(&slice_convert_lock, flags); + memset(hpsizes, (psize << 4) | psize, SLICE_NUM_HIGH >> 1); } void slice_set_range_psize(struct mm_struct *mm, unsigned long start,