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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 10A74CA6007 for ; Wed, 7 Oct 2026 15:36:52 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id C2C5410E60B; Wed, 7 Oct 2026 15:36:51 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="D5IeN6XY"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id DD32310E4A3 for ; Wed, 7 Oct 2026 15:36:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1791387411; x=1822923411; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=oqGquNhYv9lBDrIUsGR2l/ExzkE8Y5cxEfGHv0t5gT0=; b=D5IeN6XY/qWhRLvkt6s4f+2vccqTjS+dNRuGtBzCgjXU4aJ1fl5WAmE2 bQbNvK6Dl4dnh8lUiTYYSLQobShs/Nruf2kr80G4DbCkZrrRqjHe3z5zi yxiBAwEkmNKPGSnwHQEBFq0NbS04SktmMRrMuAf1RU8jWg+uPqukr5M+x tnjU1hIpOZpZ7Em46ozTCYzUpodqpKMIjJdn3c/6tmrhS3oiijRhl6qzg JRRRRuYO4STzCOJRdru0w3cn+Uy2bAeAd51eZMcvhBw1Ya0ikimY3ewqW KP//49sTuV9M/N1DeFxA7lUww18gJdjd/BSVd4/FxVpguc7ZSGqrBvhMV Q==; X-CSE-ConnectionGUID: Y658PivxSrOOUUQDZkBDZw== X-CSE-MsgGUID: BcvNUhS/T5eOn5EoCcdz2g== X-IronPort-AV: E=McAfee;i="6800,10657,11928"; a="148787" X-IronPort-AV: E=Sophos;i="6.27,144,1787036400"; d="scan'208";a="148787" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Oct 2026 08:36:50 -0700 X-CSE-ConnectionGUID: 5OJabNkRT2qCbxQDkXX9Ow== X-CSE-MsgGUID: DRpgFUUsTl2EH1lnGPAQqg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,144,1787036400"; d="scan'208";a="277583533" Received: from ettammin-mobl3.ger.corp.intel.com (HELO mwauld-desk.intel.com) ([10.245.244.246]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Oct 2026 08:36:49 -0700 From: Matthew Auld To: intel-xe@lists.freedesktop.org Cc: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Matthew Brost , stable@vger.kernel.org Subject: [PATCH v2 2/3] drm/xe/vm: make PREFETCH to TT sticky Date: Wed, 7 Oct 2026 16:36:08 +0100 Message-ID: <20261007153605.1743626-7-matthew.auld@intel.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20261007153605.1743626-5-matthew.auld@intel.com> References: <20261007153605.1743626-5-matthew.auld@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" When userspace explicitly requests DRM_XE_VM_BIND_OP_PREFETCH to system memory (XE_PL_TT), xe_bo_migrate() moves the buffer object to TT. However, because XE_PL_TT is marked with TTM_PL_FLAG_FALLBACK in the buffer's default placement (introduced in commit 5c87fee3c96c ("drm/xe: Attempt to bring bos back to VRAM after eviction")), any subsequent validation during exec immediately migrates the buffer back to VRAM, completely undoing the userspace prefetch request. Use xe_bo_migrate_tt_sticky() when prefetching to XE_PL_TT so that the buffer remains resident in system memory across subsequent validations. Assisted-by: LLM Reported-by: Thomas Hellström Fixes: 5c87fee3c96c ("drm/xe: Attempt to bring bos back to VRAM after eviction") Signed-off-by: Matthew Auld Cc: Matthew Brost Cc: # v6.12+ Reviewed-by: Thomas Hellström --- drivers/gpu/drm/xe/xe_vm.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c index ef369df4aa26..093ad3e39608 100644 --- a/drivers/gpu/drm/xe/xe_vm.c +++ b/drivers/gpu/drm/xe/xe_vm.c @@ -3428,7 +3428,10 @@ static int op_lock_and_prep(struct drm_exec *exec, struct xe_vm *vm, mem_type = region_to_mem_type[region]; } - err = xe_bo_migrate(bo, mem_type, NULL, exec); + if (mem_type == XE_PL_TT) + err = xe_bo_migrate_tt_sticky(bo, NULL, exec); + else + err = xe_bo_migrate(bo, mem_type, NULL, exec); } break; } -- 2.55.0