From patchwork Thu Jun 7 09:58:10 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10451581 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1205960375 for ; Thu, 7 Jun 2018 10:03:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 037D520407 for ; Thu, 7 Jun 2018 10:03:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id ECADC285BD; Thu, 7 Jun 2018 10:03:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 9122520407 for ; Thu, 7 Jun 2018 10:03:18 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1D1676F20B; Thu, 7 Jun 2018 10:03:18 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id EC2356F209 for ; Thu, 7 Jun 2018 10:03:16 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 11970965-1500050 for multiple; Thu, 07 Jun 2018 10:58:52 +0100 Received: by haswell.alporthouse.com (sSMTP sendmail emulation); Thu, 07 Jun 2018 10:58:51 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Thu, 7 Jun 2018 10:58:10 +0100 Message-Id: <20180607095815.10938-16-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180607095815.10938-1-chris@chris-wilson.co.uk> References: <20180607095815.10938-1-chris@chris-wilson.co.uk> X-Originating-IP: 78.156.65.138 X-Country: code=GB country="United Kingdom" ip=78.156.65.138 Subject: [Intel-gfx] [PATCH 15/20] drm/i915/gtt: Free unused page tables on unbind the context X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP As we cannot reliably change used page tables while the context is active, the earliest opportunity we have to recover excess pages is when the context becomes idle. So whenever we unbind the context (it must be idle, and indeed being evicted) free the unused ptes. Signed-off-by: Chris Wilson Cc: Joonas Lahtinen Cc: Mika Kuoppala Cc: Matthew Auld Reviewed-by: Matthew Auld --- drivers/gpu/drm/i915/i915_gem_gtt.c | 44 +++++++++++++++++++++++++---- drivers/gpu/drm/i915/i915_gem_gtt.h | 1 + 2 files changed, 40 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 660596ebd3c1..838ac936d843 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -1814,20 +1814,28 @@ static void gen6_ppgtt_enable(struct drm_i915_private *dev_priv) static void gen6_ppgtt_clear_range(struct i915_address_space *vm, u64 start, u64 length) { - struct i915_hw_ppgtt *ppgtt = i915_vm_to_ppgtt(vm); + struct gen6_hw_ppgtt *ppgtt = to_gen6_ppgtt(i915_vm_to_ppgtt(vm)); unsigned int first_entry = start >> PAGE_SHIFT; unsigned int pde = first_entry / GEN6_PTES; unsigned int pte = first_entry % GEN6_PTES; unsigned int num_entries = length >> PAGE_SHIFT; - gen6_pte_t scratch_pte = + const gen6_pte_t scratch_pte = vm->pte_encode(vm->scratch_page.daddr, I915_CACHE_LLC, 0); while (num_entries) { - struct i915_page_table *pt = ppgtt->pd.page_table[pde++]; - unsigned int end = min(pte + num_entries, GEN6_PTES); + struct i915_page_table *pt = ppgtt->base.pd.page_table[pde++]; + const unsigned int end = min(pte + num_entries, GEN6_PTES); + const unsigned int count = end - pte; gen6_pte_t *vaddr; - num_entries -= end - pte; + GEM_BUG_ON(pt == vm->scratch_pt); + + num_entries -= count; + + GEM_BUG_ON(count > pt->used_ptes); + pt->used_ptes -= count; + if (!pt->used_ptes) + ppgtt->scan_for_unused_pt = true; /* * Note that the hw doesn't support removing PDE on the fly @@ -1859,6 +1867,8 @@ static void gen6_ppgtt_insert_entries(struct i915_address_space *vm, struct sgt_dma iter = sgt_dma(vma); gen6_pte_t *vaddr; + GEM_BUG_ON(ppgtt->pd.page_table[act_pt] == vm->scratch_pt); + vaddr = kmap_atomic_px(ppgtt->pd.page_table[act_pt]); do { vaddr[act_pte] = pte_encode | GEN6_PTE_ADDR_ENCODE(iter.dma); @@ -1894,6 +1904,8 @@ static int gen6_alloc_va_range(struct i915_address_space *vm, bool flush = false; gen6_for_each_pde(pt, &ppgtt->base.pd, start, length, pde) { + const unsigned int count = gen6_pte_count(start, length); + if (pt == vm->scratch_pt) { pt = alloc_pt(vm); if (IS_ERR(pt)) @@ -1907,7 +1919,11 @@ static int gen6_alloc_va_range(struct i915_address_space *vm, gen6_write_pde(ppgtt, pde, pt); flush = true; } + + GEM_BUG_ON(pt->used_ptes); } + + pt->used_ptes += count; } if (flush) { @@ -2009,6 +2025,24 @@ static int pd_vma_bind(struct i915_vma *vma, static void pd_vma_unbind(struct i915_vma *vma) { + struct gen6_hw_ppgtt *ppgtt = vma->private; + struct i915_page_table * const scratch_pt = ppgtt->base.vm.scratch_pt; + struct i915_page_table *pt; + unsigned int pde; + + if (!ppgtt->scan_for_unused_pt) + return; + + /* Free all no longer used page tables */ + gen6_for_all_pdes(pt, &ppgtt->base.pd, pde) { + if (pt->used_ptes || pt == scratch_pt) + continue; + + free_pt(&ppgtt->base.vm, pt); + ppgtt->base.pd.page_table[pde] = scratch_pt; + } + + ppgtt->scan_for_unused_pt = false; } static const struct i915_vma_ops pd_vma_ops = { diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h index c20a4f06db37..dc98830fae69 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.h +++ b/drivers/gpu/drm/i915/i915_gem_gtt.h @@ -414,6 +414,7 @@ struct gen6_hw_ppgtt { gen6_pte_t __iomem *pd_addr; unsigned int pin_count; + bool scan_for_unused_pt; int (*switch_mm)(struct gen6_hw_ppgtt *ppgtt, struct i915_request *rq); };