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 8D602CA5FA1 for ; Mon, 28 Sep 2026 16:49:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 28A6A10EB31; Mon, 28 Sep 2026 16:49:04 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="JSYB16A5"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.7]) by gabe.freedesktop.org (Postfix) with ESMTPS id DAEF210E941 for ; Mon, 28 Sep 2026 16:49:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1790614141; x=1822150141; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=3O9snaNpj61NGwVpqAErbcwvbhUst7HrWJg9lEhq4og=; b=JSYB16A5A2VyarACDRPnjBd906bs0kuJlFRN6LuJrpGygZOy64mKdDTK DU/CXX/dAkmA4mLXB2tREF1bDsLq0mlXzvWC3Az2BGoRSPSfuOGvW5ZvD DoGgWUUp4r3TvUuGBNdFV053QQUtYK/LojLW1kE4GcThc61fxBO08N1wL Y/BiFb0N/N9MK3RSkjsmJmUhuitHpYMoF3RpDNcKx1ww6uRwPEeYjCQlG u5VYmX4BYUL3BscZrp7AMM3KKtr8WRnCNyXtI2xKSzVX5TIgypSIAkOWu 4LVZUsgaBv+48e5Wa9jXCYQ0nqsqDfE0LYiPixcM/mWb/Hum8jwXBonPg w==; X-CSE-ConnectionGUID: HliwTD8US9W3KTnJIB36RA== X-CSE-MsgGUID: qeiOgbT+QcuEe/wp+pUSwQ== X-IronPort-AV: E=McAfee;i="6800,10657,11919"; a="116845572" X-IronPort-AV: E=Sophos;i="6.27,128,1787036400"; d="scan'208";a="116845572" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Sep 2026 09:49:01 -0700 X-CSE-ConnectionGUID: ufmkoWpKQeizC3j95ZccbQ== X-CSE-MsgGUID: W81AKXMNRQ2F3mzQOlT8Sg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,128,1787036400"; d="scan'208";a="301404251" Received: from pgcooper-mobl3.ger.corp.intel.com (HELO mwauld-desk.intel.com) ([10.245.244.80]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Sep 2026 09:49:01 -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 2/2] drm/xe/vm: make PREFETCH to TT sticky Date: Mon, 28 Sep 2026 17:48:23 +0100 Message-ID: <20260928164820.1237049-6-matthew.auld@intel.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260928164820.1237049-4-matthew.auld@intel.com> References: <20260928164820.1237049-4-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+ --- 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 425c678f4480..2068e0cf50ff 100644 --- a/drivers/gpu/drm/xe/xe_vm.c +++ b/drivers/gpu/drm/xe/xe_vm.c @@ -3406,7 +3406,10 @@ 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