From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33372C433EF for ; Tue, 12 Oct 2021 00:06:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13E8B61038 for ; Tue, 12 Oct 2021 00:06:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233990AbhJLAI3 (ORCPT ); Mon, 11 Oct 2021 20:08:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231352AbhJLAIX (ORCPT ); Mon, 11 Oct 2021 20:08:23 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D018C06161C; Mon, 11 Oct 2021 17:06:22 -0700 (PDT) Message-ID: <20211011223610.950054267@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1633997181; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=4EHKPcl4JlAkis6eUZZQUW/49IdenRLk1IEf79GkDUo=; b=enbtcQDhqeYiyz2Z/05myFc/NHMseN8qMYLy5yOCCpOqN52G8ISj1qOxeT9Il4+UaXeWKi XlKiikJiVvSWqLo1ctNjytPyUsVMHmn5rRhgj21e3qOAsM7KByXJAYmd9sLoD8V5OfC1h0 jFI7m5ACjVwiV1F8EISv0i+jPEN+JWA8mMWYcfooGjuwqdy4XDCiJ25inzPAaliPZ4PdsT c3YDTEJkW62G3//if7bALwTxKebY31+Py1GOAq85Ut6L4ImLiaT/mbxraTfuXXIJ9cbDwv mA6i1efdWgrCZNWl6MdTLiZufI9JEmaJJfVLmSQdeiw+t+Fq9ehPQnlo2jTdig== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1633997181; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=4EHKPcl4JlAkis6eUZZQUW/49IdenRLk1IEf79GkDUo=; b=lMnZZ8wHxx2R97Q0c0pAzokvQkIx3zsYmLLWcxBqJ/wY/5kmxfcZecJvOjPG3gj3atdSOU y/3QXBAImZc9DSBA== From: Thomas Gleixner To: LKML Cc: x86@kernel.org, "Chang S. Bae" , Dave Hansen , Arjan van de Ven , kvm@vger.kernel.org, Paolo Bonzini Subject: [patch 11/31] x86/fpu/xstate: Provide and use for_each_xfeature() References: <20211011215813.558681373@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Date: Tue, 12 Oct 2021 02:00:14 +0200 (CEST) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org These loops evaluating xfeature bits are really hard to read. Create an iterator and use for_each_set_bit_from() inside which already does the right thing. Signed-off-by: Thomas Gleixner --- arch/x86/kernel/fpu/xstate.c | 56 +++++++++++++++++-------------------------- 1 file changed, 23 insertions(+), 33 deletions(-) --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -4,6 +4,7 @@ * * Author: Suresh Siddha */ +#include #include #include #include @@ -20,6 +21,10 @@ #include "xstate.h" +#define for_each_extended_xfeature(bit, mask) \ + (bit) = FIRST_EXTENDED_XFEATURE; \ + for_each_set_bit_from(bit, (unsigned long *)&(mask), 8 * sizeof(mask)) + /* * Although we spell it out in here, the Processor Trace * xfeature is completely unused. We use other mechanisms @@ -184,10 +189,7 @@ static void __init setup_xstate_features xstate_sizes[XFEATURE_SSE] = sizeof_field(struct fxregs_state, xmm_space); - for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { - if (!xfeature_enabled(i)) - continue; - + for_each_extended_xfeature(i, xfeatures_mask_all) { cpuid_count(XSTATE_CPUID, i, &eax, &ebx, &ecx, &edx); xstate_sizes[i] = eax; @@ -291,20 +293,15 @@ static void __init setup_xstate_comp_off xstate_comp_offsets[XFEATURE_SSE] = offsetof(struct fxregs_state, xmm_space); - if (!boot_cpu_has(X86_FEATURE_XSAVES)) { - for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { - if (xfeature_enabled(i)) - xstate_comp_offsets[i] = xstate_offsets[i]; - } + if (!cpu_feature_enabled(X86_FEATURE_XSAVES)) { + for_each_extended_xfeature(i, xfeatures_mask_all) + xstate_comp_offsets[i] = xstate_offsets[i]; return; } next_offset = FXSAVE_SIZE + XSAVE_HDR_SIZE; - for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { - if (!xfeature_enabled(i)) - continue; - + for_each_extended_xfeature(i, xfeatures_mask_all) { if (xfeature_is_aligned(i)) next_offset = ALIGN(next_offset, 64); @@ -328,8 +325,8 @@ static void __init setup_supervisor_only next_offset = FXSAVE_SIZE + XSAVE_HDR_SIZE; - for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { - if (!xfeature_enabled(i) || !xfeature_is_supervisor(i)) + for_each_extended_xfeature(i, xfeatures_mask_all) { + if (!xfeature_is_supervisor(i)) continue; if (xfeature_is_aligned(i)) @@ -347,9 +344,7 @@ static void __init print_xstate_offset_s { int i; - for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { - if (!xfeature_enabled(i)) - continue; + for_each_extended_xfeature(i, xfeatures_mask_all) { pr_info("x86/fpu: xstate_offset[%d]: %4d, xstate_sizes[%d]: %4d\n", i, xstate_comp_offsets[i], i, xstate_sizes[i]); } @@ -554,10 +549,7 @@ static void do_extra_xstate_size_checks( int paranoid_xstate_size = FXSAVE_SIZE + XSAVE_HDR_SIZE; int i; - for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { - if (!xfeature_enabled(i)) - continue; - + for_each_extended_xfeature(i, xfeatures_mask_all) { check_xstate_against_struct(i); /* * Supervisor state components can be managed only by @@ -586,7 +578,6 @@ static void do_extra_xstate_size_checks( XSTATE_WARN_ON(paranoid_xstate_size != fpu_kernel_xstate_size); } - /* * Get total size of enabled xstates in XCR0 | IA32_XSS. * @@ -969,6 +960,7 @@ void copy_xstate_to_uabi_buf(struct memb struct xregs_state *xinit = &init_fpstate.xsave; struct xstate_header header; unsigned int zerofrom; + u64 mask; int i; memset(&header, 0, sizeof(header)); @@ -1022,17 +1014,15 @@ void copy_xstate_to_uabi_buf(struct memb zerofrom = offsetof(struct xregs_state, extended_state_area); - for (i = FIRST_EXTENDED_XFEATURE; i < XFEATURE_MAX; i++) { - /* - * The ptrace buffer is in non-compacted XSAVE format. - * In non-compacted format disabled features still occupy - * state space, but there is no state to copy from in the - * compacted init_fpstate. The gap tracking will zero this - * later. - */ - if (!(xfeatures_mask_uabi() & BIT_ULL(i))) - continue; + /* + * The ptrace buffer is in non-compacted XSAVE format. In + * non-compacted format disabled features still occupy state space, + * but there is no state to copy from in the compacted + * init_fpstate. The gap tracking will zero these states. + */ + mask = xfeatures_mask_uabi(); + for_each_extended_xfeature(i, mask) { /* * If there was a feature or alignment gap, zero the space * in the destination buffer.