From patchwork Wed Mar 5 20:26:30 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Upton X-Patchwork-Id: 14003522 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 244A8C28B22 for ; Wed, 5 Mar 2025 22:18:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xfqIKZG28S2rSPiEQ0brMIbgRTgMNYuFfI/4SHaMPU8=; b=qwZ/frmodCK+SisXnXCUhXNg5c WJG4Z4S2k3RxD5A3lhI824jLAj7uL/8kWwzEpyOKNxOjnZLU/HFPcTzlYJBYug1D7f+a2POdqDMCJ xJIBOZxpy4Yuvdl8tk8Rr41XNru1S6JVOvbEjfEqkPLFMAioTnOfNcly/04i4vFf3qeJVaeV3SrZ1 tlU6fCzhzhXyY0+Kc7ufxvGAOKokLmTNin5OsQrObHPoypiF+PYAbmwO+ysnMJ8b1SmdvyPi93h/A f5nYz/7hR7Py4WMKj5qT+y8r9kO7b79KCgA/9kTGtrfGYkBpPhvJW80A6WENioYCpHA8tDYbWnqUA HVUBMbqA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tpx4i-00000009Sa0-2FBL; Wed, 05 Mar 2025 22:18:48 +0000 Received: from out-187.mta1.migadu.com ([95.215.58.187]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tpvKf-00000009D6E-1v2v for linux-arm-kernel@lists.infradead.org; Wed, 05 Mar 2025 20:27:10 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1741206422; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xfqIKZG28S2rSPiEQ0brMIbgRTgMNYuFfI/4SHaMPU8=; b=Uu01N3n1m/d2hGWqII/ulvPTDgJK4auB0XLXgXIOUpzA2VtKUL6P1gZDlKnN23VYW9rJQD IlBIPwJDIvD2XJU1CciUwTwoCyBjsl9zlbHhH9JyUPEMTEJczBg7iXW1nK2ZF09O7Z0Unb nA0X/Zn8YlXNBRl9rcAbsz5yxQBsDMw= From: Oliver Upton To: kvmarm@lists.linux.dev Cc: Marc Zyngier , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Mingwei Zhang , Colton Lewis , Raghavendra Rao Ananta , Catalin Marinas , Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Janne Grunau , Oliver Upton Subject: [PATCH v3 03/14] KVM: arm64: Compute PMCEID from arm_pmu's event bitmaps Date: Wed, 5 Mar 2025 12:26:30 -0800 Message-Id: <20250305202641.428114-4-oliver.upton@linux.dev> In-Reply-To: <20250305202641.428114-1-oliver.upton@linux.dev> References: <20250305202641.428114-1-oliver.upton@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250305_122709_648416_492ABCF7 X-CRM114-Status: GOOD ( 12.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The PMUv3 driver populates a couple of bitmaps with the values of PMCEID{0,1}, from which the guest's PMCEID{0,1} can be derived. This is particularly convenient when virtualizing PMUv3 on IMP DEF hardware, as reading the nonexistent PMCEID registers leads to a rather unpleasant UNDEF. Tested-by: Janne Grunau Signed-off-by: Oliver Upton --- arch/arm64/kvm/pmu-emul.c | 47 ++++++++++++++++++++++++++++++--------- 1 file changed, 36 insertions(+), 11 deletions(-) diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 6c5950b9ceac..104672a0c5a2 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -842,8 +842,42 @@ static struct arm_pmu *kvm_pmu_probe_armpmu(void) return pmu; } +static u64 __compute_pmceid(struct arm_pmu *pmu, bool pmceid1) +{ + u32 hi[2], lo[2]; + + bitmap_to_arr32(lo, pmu->pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); + bitmap_to_arr32(hi, pmu->pmceid_ext_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); + + return ((u64)hi[pmceid1] << 32) | lo[pmceid1]; +} + +static u64 compute_pmceid0(struct arm_pmu *pmu) +{ + u64 val = __compute_pmceid(pmu, 0); + + /* always support CHAIN */ + val |= BIT(ARMV8_PMUV3_PERFCTR_CHAIN); + return val; +} + +static u64 compute_pmceid1(struct arm_pmu *pmu) +{ + u64 val = __compute_pmceid(pmu, 1); + + /* + * Don't advertise STALL_SLOT*, as PMMIR_EL0 is handled + * as RAZ + */ + val &= ~(BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32) | + BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND - 32) | + BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND - 32)); + return val; +} + u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) { + struct arm_pmu *cpu_pmu = vcpu->kvm->arch.arm_pmu; unsigned long *bmap = vcpu->kvm->arch.pmu_filter; u64 val, mask = 0; int base, i, nr_events; @@ -852,19 +886,10 @@ u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) return 0; if (!pmceid1) { - val = read_sysreg(pmceid0_el0); - /* always support CHAIN */ - val |= BIT(ARMV8_PMUV3_PERFCTR_CHAIN); + val = compute_pmceid0(cpu_pmu); base = 0; } else { - val = read_sysreg(pmceid1_el0); - /* - * Don't advertise STALL_SLOT*, as PMMIR_EL0 is handled - * as RAZ - */ - val &= ~(BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32) | - BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND - 32) | - BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND - 32)); + val = compute_pmceid1(cpu_pmu); base = 32; }