From patchwork Tue Jun 6 13:24:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Piggin X-Patchwork-Id: 1791174 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=2404:9400:2:0:216:3eff:fee1:b9f1; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20221208 header.b=fFB3ltwh; dkim-atps=neutral Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2404:9400:2:0:216:3eff:fee1:b9f1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4QbB8X4wzdz20QH for ; Tue, 6 Jun 2023 23:26:52 +1000 (AEST) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4QbB8W59Bbz3fJ8 for ; Tue, 6 Jun 2023 23:26:51 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20221208 header.b=fFB3ltwh; 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 (sender SPF authorized) smtp.mailfrom=gmail.com (client-ip=2607:f8b0:4864:20::52b; helo=mail-pg1-x52b.google.com; envelope-from=npiggin@gmail.com; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20221208 header.b=fFB3ltwh; dkim-atps=neutral Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4QbB6S6zNBz3dsb for ; Tue, 6 Jun 2023 23:25:04 +1000 (AEST) Received: by mail-pg1-x52b.google.com with SMTP id 41be03b00d2f7-543a6cc5f15so2341141a12.2 for ; Tue, 06 Jun 2023 06:25:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1686057902; x=1688649902; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=gPiTwbD/urG3YDVam4lKmMQHRx/vZY2THnt7HZL6g5A=; b=fFB3ltwhdNHwvn4Q3d4svAnWTcRsX5y4OuY2eXknbOCR71+Iwb5iznIHqUlrsJMnld kV+53+mOHC8uiUhzEgfq94L5vbEmBoKyKuiVqloFCW190g62/gyUHofwJi/QarCsS7CA 0ls2uKhDaMNb6ikI1D6RNlWXGmEGlS0zOaG1dHB3kN7lsEC7HhNrcHca6613AzmHKBIh A7UIfHwtXXltWuQNBt29Iw3uElFH/zX8ywg0QAGsE+wqgPjf+ArhxrFMOHWTVh3YopAB fL0IGEAhMy6SDn43cKtLBYfHFneDT2OIYvOGjxduqw6sXjklr7JHQcWK58oGWQIExGq0 7BpA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686057902; x=1688649902; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=gPiTwbD/urG3YDVam4lKmMQHRx/vZY2THnt7HZL6g5A=; b=L8uf9IcVfXfarCOLC6L4RG3KZDO6ckxvivTBw9bY4rzqFnJefGi+wEHd3jSXsCeCoe hiFjbm/twi4mXFsfDDColyoeXBln5mOY1MZSmYfYUfHoDVD7+eQ+if9hI4zZ6uT3FWX8 nEiKtz+kOS81vs1WPyX0Q0857Iq5u0oC4v/Pe9t8FctO7ppVbFIrqq1VgPyodiAcJr+8 euKjCnbCYvFjqZbaFIemNNyrpZYdF2SCJ/cRXZAWAETYi069dCbPT0NY7/Otu2HQwLat xjK2eulcrcvh9vtvGG46HeY/l2WJO41Iq4FKVOSnURk4tyOtWzoiW5qrJMO505DaQERs PKNg== X-Gm-Message-State: AC+VfDy4cTgw/Iy3yh+pZU22nk1iQ+KfuJyJeU8kQYqbAkup+f75XsdP OLo5tOrUxymxMGOrVsK5k/MM2Of5lvU= X-Google-Smtp-Source: ACHHUZ6TTuvFl3lqmVrQZ3POwc/Astpa0f26PxAdJH6h6RDXeKmaWGUPtuxmfwLNTereca42QQ34gQ== X-Received: by 2002:a17:903:228c:b0:1af:e295:ad56 with SMTP id b12-20020a170903228c00b001afe295ad56mr2639951plh.49.1686057902243; Tue, 06 Jun 2023 06:25:02 -0700 (PDT) Received: from wheely.local0.net (58-6-230-127.tpgi.com.au. [58.6.230.127]) by smtp.gmail.com with ESMTPSA id jd18-20020a170903261200b001ac2c3e54adsm8522132plb.118.2023.06.06.06.25.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 06 Jun 2023 06:25:01 -0700 (PDT) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v3 2/6] powerpc/64: Rearrange 64-bit _switch to prepare for 32/64 merge Date: Tue, 6 Jun 2023 23:24:43 +1000 Message-Id: <20230606132447.315714-3-npiggin@gmail.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230606132447.315714-1-npiggin@gmail.com> References: <20230606132447.315714-1-npiggin@gmail.com> MIME-Version: 1.0 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nicholas Piggin Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" More some 64-bit specifics out from the function epilogue and rearrange this to be a bit neater, use 32-bit mem ops for CR save/restore, and change some register numbers. This is preparation to consolidate 32-bit and 64-bit switch code. Signed-off-by: Nicholas Piggin --- arch/powerpc/kernel/entry_64.S | 38 ++++++++++++++++------------------ 1 file changed, 18 insertions(+), 20 deletions(-) diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 2e02834c5824..7430bd020a2a 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -190,12 +190,13 @@ _GLOBAL(_switch) mflr r0 std r0,16(r1) stdu r1,-SWITCH_FRAME_SIZE(r1) + std r1,KSP(r3) /* Set old stack pointer */ /* r3-r13 are caller saved -- Cort */ SAVE_NVGPRS(r1) std r0,_NIP(r1) /* Return to switch caller */ - mfcr r23 - std r23,_CCR(r1) - std r1,KSP(r3) /* Set old stack pointer */ + mfcr r0 + stw r0,_CCR(r1) + ld r8,KSP(r4) /* Load new stack pointer */ kuap_check_amr r9, r10 @@ -232,14 +233,20 @@ _GLOBAL(_switch) DCBT_BOOK3S_STOP_ALL_STREAM_IDS(r6) #endif - addi r6,r4,-THREAD /* Convert THREAD to 'current' */ - std r6,PACACURRENT(r13) /* Set new 'current' */ + addi r3,r3,-THREAD /* old thread -> task_struct for return value */ + addi r6,r4,-THREAD /* new thread -> task_struct */ + std r6,PACACURRENT(r13) /* Set new task_struct to 'current' */ #if defined(CONFIG_STACKPROTECTOR) ld r6, TASK_CANARY(r6) std r6, PACA_CANARY(r13) #endif - - ld r8,KSP(r4) /* new stack pointer */ + /* Set the new PACAKSAVE */ + clrrdi r7, r8, THREAD_SHIFT /* base of new stack */ + /* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE + because we don't need to leave the 288-byte ABI gap at the + top of the kernel stack. */ + addi r7,r7,THREAD_SIZE-SWITCH_FRAME_SIZE + std r7,PACAKSAVE(r13) #ifdef CONFIG_PPC_64S_HASH_MMU BEGIN_MMU_FTR_SECTION @@ -247,12 +254,6 @@ BEGIN_MMU_FTR_SECTION END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) #endif - clrrdi r7, r8, THREAD_SHIFT /* base of new stack */ - /* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE - because we don't need to leave the 288-byte ABI gap at the - top of the kernel stack. */ - addi r7,r7,THREAD_SIZE-SWITCH_FRAME_SIZE - /* * PMU interrupts in radix may come in here. They will use r1, not * PACAKSAVE, so this stack switch will not cause a problem. They @@ -262,18 +263,15 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) * active on the new CPU, will order those stores. */ mr r1,r8 /* start using new stack pointer */ - std r7,PACAKSAVE(r13) - ld r6,_CCR(r1) - mtcrf 0xFF,r6 + lwz r0,_CCR(r1) + mtcrf 0xFF,r0 /* r3-r13 are destroyed -- Cort */ REST_NVGPRS(r1) - /* convert old thread to its task_struct for return value */ - addi r3,r3,-THREAD - ld r7,_NIP(r1) /* Return to _switch caller in new task */ - mtlr r7 + ld r0,_NIP(r1) /* Return to _switch caller in new task */ + mtlr r0 addi r1,r1,SWITCH_FRAME_SIZE blr