From nobody Mon Feb 9 23:38:58 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) client-ip=66.175.222.108; envelope-from=bounce+27952+112109+1787277+3901457@groups.io; helo=mail02.groups.io; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+112109+1787277+3901457@groups.io; dmarc=fail(p=none dis=none) header.from=intel.com ARC-Seal: i=1; a=rsa-sha256; t=1701856893; cv=none; d=zohomail.com; s=zohoarc; b=W4hWPAwna/JUByIbD1YLZu1W1sltMGNRgVg4lydMTKp9fjoitQ7CYH9Lp9HdgycMMDJBGrufmsrvYHtsK5zT7eD3CNcrFiqJRTiaeS0b0b7MaG5qxMmoMnb0roIBELN1KoGtfK356chVT8bMFPHuZ7KTh+dQMpcPI4mRMcRo8H4= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1701856893; h=Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Id:List-Help:List-Unsubscribe:Message-ID:Reply-To:Reply-To:References:Sender:Subject:Subject:To:To:Message-Id; bh=BA0RN6D/CVRejGuueedxJqa5uHI5YrLIRsTvKM0mmEo=; b=So/kaD8/3R4WyT5hVexp6FwyzDJfIJ7tmltAsybf5V2G76GADOp4/JQzfxz2K3kvL2uvnBf0pBM1mkgTRvyCfahcyDWy/jo7CSsY4lgJWhgsSGcwaU72OB/AE3YJ++oERqXSZaQdV7EOovnlzCCH3dULHeRjOwWjK6IHSVqT1Eg= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+112109+1787277+3901457@groups.io; dmarc=fail header.from= (p=none dis=none) Received: from mail02.groups.io (mail02.groups.io [66.175.222.108]) by mx.zohomail.com with SMTPS id 17018568936491010.2262226220581; Wed, 6 Dec 2023 02:01:33 -0800 (PST) Return-Path: DKIM-Signature: a=rsa-sha256; bh=gD6p6yr3moFfeTckpg57j8nS6ElTl64HtakxqaOlwSc=; c=relaxed/simple; d=groups.io; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References:Precedence:List-Subscribe:List-Help:Sender:List-Id:Mailing-List:Delivered-To:Reply-To:List-Unsubscribe-Post:List-Unsubscribe; s=20140610; t=1701856893; v=1; b=pgXdFnVhr+huq8KktvA+/lbrGG0cMDonPfa+Q+SVkUklhYP+2/J6fUp43VZQfIMwAME3apOL vdT4sdelNGtticPrf68W4ScWxkIWczAZHnTWU36zKHpW71Z7fRtqgisvsZR8awfR8d+UzB9MQrr 8luLoVuokM+teJvYr9MwOcuE= X-Received: by 127.0.0.2 with SMTP id QBUaYY1788612xtvFJ6M4Qdl; Wed, 06 Dec 2023 02:01:33 -0800 X-Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.10]) by mx.groups.io with SMTP id smtpd.web11.28132.1701856892226271583 for ; Wed, 06 Dec 2023 02:01:32 -0800 X-IronPort-AV: E=McAfee;i="6600,9927,10915"; a="1130561" X-IronPort-AV: E=Sophos;i="6.04,254,1695711600"; d="scan'208";a="1130561" X-Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmvoesa104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Dec 2023 02:01:32 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10915"; a="841775343" X-IronPort-AV: E=Sophos;i="6.04,254,1695711600"; d="scan'208";a="841775343" X-Received: from sh1gapp1009.ccr.corp.intel.com ([10.239.189.219]) by fmsmga004.fm.intel.com with ESMTP; 06 Dec 2023 02:01:26 -0800 From: "Wu, Jiaxin" To: devel@edk2.groups.io Cc: Laszlo Ersek , Eric Dong , Ray Ni , Zeng Star , Rahul Kumar , Gerd Hoffmann Subject: [edk2-devel] [PATCH v3 1/6] UefiCpuPkg/PiSmmCpuDxeSmm: Optimize Semaphore Sync between BSP and AP Date: Wed, 6 Dec 2023 18:01:17 +0800 Message-Id: <20231206100122.8028-2-jiaxin.wu@intel.com> In-Reply-To: <20231206100122.8028-1-jiaxin.wu@intel.com> References: <20231206100122.8028-1-jiaxin.wu@intel.com> Precedence: Bulk List-Subscribe: List-Help: Sender: devel@edk2.groups.io List-Id: Mailing-List: list devel@edk2.groups.io; contact devel+owner@edk2.groups.io Reply-To: devel@edk2.groups.io,jiaxin.wu@intel.com List-Unsubscribe-Post: List-Unsubscribe=One-Click List-Unsubscribe: X-Gm-Message-State: QuTUMdf1vCvPGnTI8b36Nd1mx1787277AA= X-ZohoMail-DKIM: pass (identity @groups.io) X-ZM-MESSAGEID: 1701856894643100002 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" This patch is to define 3 new functions (WaitForBsp & ReleaseBsp & ReleaseOneAp) used for the semaphore sync between BSP & AP. With the change, BSP and AP Sync flow will be easy understand as below: BSP: ReleaseAllAPs or ReleaseOneAp --> AP: WaitForBsp BSP: WaitForAllAPs <-- AP: ReleaseBsp Cc: Laszlo Ersek Cc: Eric Dong Cc: Ray Ni Cc: Zeng Star Cc: Rahul Kumar Cc: Gerd Hoffmann Signed-off-by: Jiaxin Wu Reviewed-by: Laszlo Ersek --- UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c | 72 ++++++++++++++++++++++++++++---= ---- 1 file changed, 58 insertions(+), 14 deletions(-) diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c b/UefiCpuPkg/PiSmmCpuDxe= Smm/MpService.c index b279f5dfcc..54542262a2 100644 --- a/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c +++ b/UefiCpuPkg/PiSmmCpuDxeSmm/MpService.c @@ -120,10 +120,11 @@ LockdownSemaphore ( =20 return Value; } =20 /** + Used for BSP to wait all APs. Wait all APs to performs an atomic compare exchange operation to release= semaphore. =20 @param NumberOfAPs AP number =20 **/ @@ -139,10 +140,11 @@ WaitForAllAPs ( WaitForSemaphore (mSmmMpSyncData->CpuData[BspIndex].Run); } } =20 /** + Used for BSP to release all APs. Performs an atomic compare exchange operation to release semaphore for each AP. =20 **/ VOID @@ -157,10 +159,52 @@ ReleaseAllAPs ( ReleaseSemaphore (mSmmMpSyncData->CpuData[Index].Run); } } } =20 +/** + Used for BSP to release one AP. + + @param ApSem IN: 32-bit unsigned integer + OUT: original integer + 1 +**/ +VOID +ReleaseOneAp ( + IN OUT volatile UINT32 *ApSem + ) +{ + ReleaseSemaphore (ApSem); +} + +/** + Used for AP to wait BSP. + + @param ApSem IN: 32-bit unsigned integer + OUT: original integer - 1 +**/ +VOID +WaitForBsp ( + IN OUT volatile UINT32 *ApSem + ) +{ + WaitForSemaphore (ApSem); +} + +/** + Used for AP to release BSP. + + @param BspSem IN: 32-bit unsigned integer + OUT: original integer + 1 +**/ +VOID +ReleaseBsp ( + IN OUT volatile UINT32 *BspSem + ) +{ + ReleaseSemaphore (BspSem); +} + /** Check whether the index of CPU perform the package level register programming during System Management Mode initialization. =20 The index of Processor specified by mPackageFirstThreadIndex[PackageInde= x] @@ -632,11 +676,11 @@ BSPHandler ( // Signal all APs it's time for backup MTRRs // ReleaseAllAPs (); =20 // - // WaitForSemaphore() may wait for ever if an AP happens to enter SM= M at + // WaitForAllAPs() may wait for ever if an AP happens to enter SMM at // exactly this point. Please make sure PcdCpuSmmMaxSyncLoops has be= en set // to a large enough value to avoid this situation. // Note: For HT capable CPUs, threads within a core share the same s= et of MTRRs. // We do the backup first and then set MTRR to avoid race condition = for threads // in the same core. @@ -652,11 +696,11 @@ BSPHandler ( // Let all processors program SMM MTRRs together // ReleaseAllAPs (); =20 // - // WaitForSemaphore() may wait for ever if an AP happens to enter SM= M at + // WaitForAllAPs() may wait for ever if an AP happens to enter SMM at // exactly this point. Please make sure PcdCpuSmmMaxSyncLoops has be= en set // to a large enough value to avoid this situation. // ReplaceOSMtrrs (CpuIndex); =20 @@ -898,50 +942,50 @@ APHandler ( =20 if ((SyncMode =3D=3D SmmCpuSyncModeTradition) || SmmCpuFeaturesNeedConfi= gureMtrrs ()) { // // Notify BSP of arrival at this point // - ReleaseSemaphore (mSmmMpSyncData->CpuData[BspIndex].Run); + ReleaseBsp (mSmmMpSyncData->CpuData[BspIndex].Run); } =20 if (SmmCpuFeaturesNeedConfigureMtrrs ()) { // // Wait for the signal from BSP to backup MTRRs // - WaitForSemaphore (mSmmMpSyncData->CpuData[CpuIndex].Run); + WaitForBsp (mSmmMpSyncData->CpuData[CpuIndex].Run); =20 // // Backup OS MTRRs // MtrrGetAllMtrrs (&Mtrrs); =20 // // Signal BSP the completion of this AP // - ReleaseSemaphore (mSmmMpSyncData->CpuData[BspIndex].Run); + ReleaseBsp (mSmmMpSyncData->CpuData[BspIndex].Run); =20 // // Wait for BSP's signal to program MTRRs // - WaitForSemaphore (mSmmMpSyncData->CpuData[CpuIndex].Run); + WaitForBsp (mSmmMpSyncData->CpuData[CpuIndex].Run); =20 // // Replace OS MTRRs with SMI MTRRs // ReplaceOSMtrrs (CpuIndex); =20 // // Signal BSP the completion of this AP // - ReleaseSemaphore (mSmmMpSyncData->CpuData[BspIndex].Run); + ReleaseBsp (mSmmMpSyncData->CpuData[BspIndex].Run); } =20 while (TRUE) { // // Wait for something to happen // - WaitForSemaphore (mSmmMpSyncData->CpuData[CpuIndex].Run); + WaitForBsp (mSmmMpSyncData->CpuData[CpuIndex].Run); =20 // // Check if BSP wants to exit SMM // if (!(*mSmmMpSyncData->InsideSmm)) { @@ -977,16 +1021,16 @@ APHandler ( =20 if (SmmCpuFeaturesNeedConfigureMtrrs ()) { // // Notify BSP the readiness of this AP to program MTRRs // - ReleaseSemaphore (mSmmMpSyncData->CpuData[BspIndex].Run); + ReleaseBsp (mSmmMpSyncData->CpuData[BspIndex].Run); =20 // // Wait for the signal from BSP to program MTRRs // - WaitForSemaphore (mSmmMpSyncData->CpuData[CpuIndex].Run); + WaitForBsp (mSmmMpSyncData->CpuData[CpuIndex].Run); =20 // // Restore OS MTRRs // SmmCpuFeaturesReenableSmrr (); @@ -994,26 +1038,26 @@ APHandler ( } =20 // // Notify BSP the readiness of this AP to Reset states/semaphore for thi= s processor // - ReleaseSemaphore (mSmmMpSyncData->CpuData[BspIndex].Run); + ReleaseBsp (mSmmMpSyncData->CpuData[BspIndex].Run); =20 // // Wait for the signal from BSP to Reset states/semaphore for this proce= ssor // - WaitForSemaphore (mSmmMpSyncData->CpuData[CpuIndex].Run); + WaitForBsp (mSmmMpSyncData->CpuData[CpuIndex].Run); =20 // // Reset states/semaphore for this processor // *(mSmmMpSyncData->CpuData[CpuIndex].Present) =3D FALSE; =20 // // Notify BSP the readiness of this AP to exit SMM // - ReleaseSemaphore (mSmmMpSyncData->CpuData[BspIndex].Run); + ReleaseBsp (mSmmMpSyncData->CpuData[BspIndex].Run); } =20 /** Checks whether the input token is the current used token. =20 @@ -1277,11 +1321,11 @@ InternalSmmStartupThisAp ( mSmmMpSyncData->CpuData[CpuIndex].Status =3D CpuStatus; if (mSmmMpSyncData->CpuData[CpuIndex].Status !=3D NULL) { *mSmmMpSyncData->CpuData[CpuIndex].Status =3D EFI_NOT_READY; } =20 - ReleaseSemaphore (mSmmMpSyncData->CpuData[CpuIndex].Run); + ReleaseOneAp (mSmmMpSyncData->CpuData[CpuIndex].Run); =20 if (Token =3D=3D NULL) { AcquireSpinLock (mSmmMpSyncData->CpuData[CpuIndex].Busy); ReleaseSpinLock (mSmmMpSyncData->CpuData[CpuIndex].Busy); } --=20 2.16.2.windows.1 -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D- Groups.io Links: You receive all messages sent to this group. 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