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(unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 12A4717E1154; Fri, 5 Dec 2025 10:12:22 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 01/10] drm/shmem-helper: Simplify page offset calculation in fault handler Date: Fri, 5 Dec 2025 10:12:07 +0100 Message-ID: <20251205091216.150968-2-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable For a fault at address addr, the page offset is page_offset =3D (vmf->address - vma->vm_start) >> PAGE_SHIFT =3D ((addr & PAGE_MASK) - vma->vm_start) >> PAGE_SHIFT =3D (addr - vma->vm_start) >> PAGE_SHIFT Since the faulty logical page offset based on VMA is vmf->pgoff =3D vma->vm_pgoff + ((addr - vma->vm_start) >> PAGE_SHIFT) We can slightly simplify the calculation using page_offset =3D vmf->pgoff - vma->vm_pgoff v11: - remove misleading comment - add Boris R-b Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Boris Brezillon --- drivers/gpu/drm/drm_gem_shmem_helper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_g= em_shmem_helper.c index dc94a27710e5..e47ab3ebb5c2 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -577,8 +577,8 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault *= vmf) struct page *page; pgoff_t page_offset; =20 - /* We don't use vmf->pgoff since that has the fake offset */ - page_offset =3D (vmf->address - vma->vm_start) >> PAGE_SHIFT; + /* Offset to faulty address in the VMA. */ + page_offset =3D vmf->pgoff - vma->vm_pgoff; =20 dma_resv_lock(shmem->base.resv, NULL); =20 --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 08A523358D2; Fri, 5 Dec 2025 09:12:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925954; cv=none; b=S5MSO1cEjl5OqJl5dpB4cvyKOJ4jdBUosGHWqRJtSeIN9WfqxYGnwrSfFFevREqGgcNuUJr5OrY+BQzZXNS/TPjMsuTDU2/vIxrBwmThlGw7veoAHND1nOngz/rfZ5fa0N1Ug+v/1iXF8U8aTUktp/zUCq7DNMjpS1jysX0UR2k= ARC-Message-Signature: i=1; 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(unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 186DA17E126B; Fri, 5 Dec 2025 10:12:23 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 02/10] drm/shmem-helper: Map huge pages in fault handler Date: Fri, 5 Dec 2025 10:12:08 +0100 Message-ID: <20251205091216.150968-3-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Attempt a PMD sized PFN insertion into the VMA if the faulty address of the fault handler is part of a huge page. On builds with CONFIG_TRANSPARENT_HUGEPAGE enabled, if the mmap() user address is PMD size aligned, if the GEM object is backed by shmem buffers on mountpoints setting the 'huge=3D' option and if the shmem backing store manages to allocate a huge folio, CPU mapping would then benefit from significantly increased memcpy() performance. When these conditions are met on a system with 2 MiB huge pages, an aligned copy of 2 MiB would raise a single page fault instead of 4096. v4: - implement map_pages instead of huge_fault v6: - get rid of map_pages handler for now (keep it for another series along with arm64 contpte support) v11: - remove page fault validity check helper - rename drm_gem_shmem_map_pmd() to drm_gem_shmem_try_map_pmd() - add Boris R-b v12: - move up ret var decl in fault handler to minimize diff Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Boris Brezillon --- drivers/gpu/drm/drm_gem_shmem_helper.c | 35 +++++++++++++++++++++++--- 1 file changed, 31 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_g= em_shmem_helper.c index e47ab3ebb5c2..e67216cbb469 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -567,6 +567,26 @@ int drm_gem_shmem_dumb_create(struct drm_file *file, s= truct drm_device *dev, } EXPORT_SYMBOL_GPL(drm_gem_shmem_dumb_create); =20 +static bool drm_gem_shmem_try_map_pmd(struct vm_fault *vmf, unsigned long = addr, + struct page *page) +{ +#ifdef CONFIG_ARCH_SUPPORTS_PMD_PFNMAP + unsigned long pfn =3D page_to_pfn(page); + unsigned long paddr =3D pfn << PAGE_SHIFT; + bool aligned =3D (addr & ~PMD_MASK) =3D=3D (paddr & ~PMD_MASK); + + if (aligned && + pmd_none(*vmf->pmd) && + folio_test_pmd_mappable(page_folio(page))) { + pfn &=3D PMD_MASK >> PAGE_SHIFT; + if (vmf_insert_pfn_pmd(vmf, pfn, false) =3D=3D VM_FAULT_NOPAGE) + return true; + } +#endif + + return false; +} + static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf) { struct vm_area_struct *vma =3D vmf->vma; @@ -574,8 +594,9 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault *= vmf) struct drm_gem_shmem_object *shmem =3D to_drm_gem_shmem_obj(obj); loff_t num_pages =3D obj->size >> PAGE_SHIFT; vm_fault_t ret; - struct page *page; + struct page **pages =3D shmem->pages; pgoff_t page_offset; + unsigned long pfn; =20 /* Offset to faulty address in the VMA. */ page_offset =3D vmf->pgoff - vma->vm_pgoff; @@ -586,12 +607,18 @@ static vm_fault_t drm_gem_shmem_fault(struct vm_fault= *vmf) drm_WARN_ON_ONCE(obj->dev, !shmem->pages) || shmem->madv < 0) { ret =3D VM_FAULT_SIGBUS; - } else { - page =3D shmem->pages[page_offset]; + goto out; + } =20 - ret =3D vmf_insert_pfn(vma, vmf->address, page_to_pfn(page)); + if (drm_gem_shmem_try_map_pmd(vmf, vmf->address, pages[page_offset])) { + ret =3D VM_FAULT_NOPAGE; + goto out; } =20 + pfn =3D page_to_pfn(pages[page_offset]); + ret =3D vmf_insert_pfn(vma, vmf->address, pfn); + + out: dma_resv_unlock(shmem->base.resv); =20 return ret; --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2F4A53385B5; Fri, 5 Dec 2025 09:12:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; 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(unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 1DABE17E12D5; Fri, 5 Dec 2025 10:12:24 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 03/10] drm/gem: Introduce drm_gem_get_unmapped_area() fop Date: Fri, 5 Dec 2025 10:12:09 +0100 Message-ID: <20251205091216.150968-4-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable mmap() calls on the DRM file pointer currently always end up using mm_get_unmapped_area() to get a free mapping region. On builds with CONFIG_TRANSPARENT_HUGEPAGE enabled, this isn't ideal for GEM objects backed by shmem buffers on mountpoints setting the 'huge=3D' option because it can't correctly figure out the potentially huge address alignment required. This commit introduces the drm_gem_get_unmapped_area() function which is meant to be used as a get_unmapped_area file operation on the DRM file pointer to lookup GEM objects based on their fake offsets and get a properly aligned region by calling shmem_get_unmapped_area() with the right file pointer. If a GEM object isn't available at the given offset or if the caller isn't granted access to it, the function falls back to mm_get_unmapped_area(). This also makes drm_gem_get_unmapped_area() part of the default GEM file operations so that all the DRM drivers can benefit from more efficient mappings thanks to the huge page fault handler introduced in previous commit 'drm/shmem-helper: Add huge page fault handler'. The shmem_get_unmapped_area() function needs to be exported so that it can be used from the DRM subsystem. v3: - include in drm_gem.c - forward to shmem layer in builds with CONFIG_TRANSPARENT_HUGEPAGE=3Dn v6: - use GPL variant to export drm_gem_get_unmapped_area() - don't export shmem_get_unmapped_area() anymore (use f_op instead) v11: - rename drm_gem_object_lookup_from_offset() to drm_gem_object_lookup_at_offset() - add Boris R-b Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Boris Brezillon --- drivers/gpu/drm/drm_gem.c | 108 ++++++++++++++++++++++++++++++-------- include/drm/drm_gem.h | 4 ++ 2 files changed, 90 insertions(+), 22 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index efc79bbf3c73..933fc89dd648 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include #include @@ -1177,36 +1178,27 @@ int drm_gem_mmap_obj(struct drm_gem_object *obj, un= signed long obj_size, } EXPORT_SYMBOL(drm_gem_mmap_obj); =20 -/** - * drm_gem_mmap - memory map routine for GEM objects - * @filp: DRM file pointer - * @vma: VMA for the area to be mapped - * - * If a driver supports GEM object mapping, mmap calls on the DRM file - * descriptor will end up here. - * - * Look up the GEM object based on the offset passed in (vma->vm_pgoff will - * contain the fake offset we created when the GTT map ioctl was called on - * the object) and map it with a call to drm_gem_mmap_obj(). - * - * If the caller is not granted access to the buffer object, the mmap will= fail - * with EACCES. Please see the vma manager for more information. +/* + * Look up a GEM object in offset space based on the exact start address. = The + * caller must be granted access to the object. Returns a GEM object on su= ccess + * or a negative error code on failure. The returned GEM object needs to be + * released with drm_gem_object_put(). */ -int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) +static struct drm_gem_object * +drm_gem_object_lookup_at_offset(struct file *filp, unsigned long start, + unsigned long pages) { struct drm_file *priv =3D filp->private_data; struct drm_device *dev =3D priv->minor->dev; struct drm_gem_object *obj =3D NULL; struct drm_vma_offset_node *node; - int ret; =20 if (drm_dev_is_unplugged(dev)) - return -ENODEV; + return ERR_PTR(-ENODEV); =20 drm_vma_offset_lock_lookup(dev->vma_offset_manager); node =3D drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager, - vma->vm_pgoff, - vma_pages(vma)); + start, pages); if (likely(node)) { obj =3D container_of(node, struct drm_gem_object, vma_node); /* @@ -1225,14 +1217,86 @@ int drm_gem_mmap(struct file *filp, struct vm_area_= struct *vma) drm_vma_offset_unlock_lookup(dev->vma_offset_manager); =20 if (!obj) - return -EINVAL; + return ERR_PTR(-EINVAL); =20 if (!drm_vma_node_is_allowed(node, priv)) { drm_gem_object_put(obj); - return -EACCES; + return ERR_PTR(-EACCES); } =20 - ret =3D drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, + return obj; +} + +/** + * drm_gem_get_unmapped_area - get memory mapping region routine for GEM o= bjects + * @filp: DRM file pointer + * @uaddr: User address hint + * @len: Mapping length + * @pgoff: Offset (in pages) + * @flags: Mapping flags + * + * If a driver supports GEM object mapping, before ending up in drm_gem_mm= ap(), + * mmap calls on the DRM file descriptor will first try to find a free lin= ear + * address space large enough for a mapping. Since GEM objects are backed = by + * shmem buffers, this should preferably be handled by the shmem virtual m= emory + * filesystem which can appropriately align addresses to huge page sizes w= hen + * needed. + * + * Look up the GEM object based on the offset passed in (vma->vm_pgoff will + * contain the fake offset we created) and call shmem_get_unmapped_area() = with + * the right file pointer. + * + * If a GEM object is not available at the given offset or if the caller i= s not + * granted access to it, fall back to mm_get_unmapped_area(). + */ +unsigned long drm_gem_get_unmapped_area(struct file *filp, unsigned long u= addr, + unsigned long len, unsigned long pgoff, + unsigned long flags) +{ + struct drm_gem_object *obj; + unsigned long ret; + + obj =3D drm_gem_object_lookup_at_offset(filp, pgoff, len >> PAGE_SHIFT); + if (IS_ERR(obj) || !obj->filp || !obj->filp->f_op->get_unmapped_area) + return mm_get_unmapped_area(current->mm, filp, uaddr, len, 0, + flags); + + ret =3D obj->filp->f_op->get_unmapped_area(obj->filp, uaddr, len, 0, + flags); + + drm_gem_object_put(obj); + + return ret; +} +EXPORT_SYMBOL_GPL(drm_gem_get_unmapped_area); + +/** + * drm_gem_mmap - memory map routine for GEM objects + * @filp: DRM file pointer + * @vma: VMA for the area to be mapped + * + * If a driver supports GEM object mapping, mmap calls on the DRM file + * descriptor will end up here. + * + * Look up the GEM object based on the offset passed in (vma->vm_pgoff will + * contain the fake offset we created) and map it with a call to + * drm_gem_mmap_obj(). + * + * If the caller is not granted access to the buffer object, the mmap will= fail + * with EACCES. Please see the vma manager for more information. + */ +int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct drm_gem_object *obj; + int ret; + + obj =3D drm_gem_object_lookup_at_offset(filp, vma->vm_pgoff, + vma_pages(vma)); + if (IS_ERR(obj)) + return PTR_ERR(obj); + + ret =3D drm_gem_mmap_obj(obj, + drm_vma_node_size(&obj->vma_node) << PAGE_SHIFT, vma); =20 drm_gem_object_put(obj); diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 8d48d2af2649..7c8bd67d087c 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -469,6 +469,7 @@ struct drm_gem_object { .poll =3D drm_poll,\ .read =3D drm_read,\ .llseek =3D noop_llseek,\ + .get_unmapped_area =3D drm_gem_get_unmapped_area,\ .mmap =3D drm_gem_mmap, \ .fop_flags =3D FOP_UNSIGNED_OFFSET =20 @@ -506,6 +507,9 @@ void drm_gem_vm_close(struct vm_area_struct *vma); int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size, struct vm_area_struct *vma); int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma); +unsigned long drm_gem_get_unmapped_area(struct file *filp, unsigned long u= addr, + unsigned long len, unsigned long pgoff, + unsigned long flags); =20 /** * drm_gem_object_get - acquire a GEM buffer object reference --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2A543337103; Fri, 5 Dec 2025 09:12:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925954; cv=none; b=iM+bmUFRLE4sh4eDxZoIFYCLqHkG7KQ2nHQO1kZMUzs+sn5mAXL252i7PIDCPRHsnN9aFgwwdi9cNNIvDGBR/TEj/z4phX4hXZWz59RQrEO+ToIQcYDZIsBHjQIEPAxbYdQJMNphuryuYzhpiU2smT8RYSAlKbGg42fxaND+pr8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925954; c=relaxed/simple; bh=9th0tLAngJVGd6qH652rQnjACAMqlVf6KbfxdfP115A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ikcTx09W4yNYH7VIkg+lTubmdwgHO1nZOTTzIc+tNL3qD8eOu3rUcetRskoISI0n/HeykHHXJNKKVkKjiN4FrrVBINwZwO9qDzKDgE23eDQSnaBBsnbpbsd/PYcbjO3XufD6vW9TOhzqFgNO4EI7Kv4brkMzb2Dej6Gt2UEHaYQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=iDZ32TT6; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="iDZ32TT6" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1764925946; bh=9th0tLAngJVGd6qH652rQnjACAMqlVf6KbfxdfP115A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iDZ32TT6H8iFGyCvNNO1TJ6VEiuqvfBFgZt3zhsS6GkUzB/PzYfUNqY0Efe7YTbiQ Ryvih6SDWs2H0o28Sn/1r3T4aXN/NQ9saKc0r9H5JU4BeT5nefgrkICyyxFa/2DaO2 PTzrN9/H8niEVYl/tREio4W0689SsISXQ//znVm1yP5zCMuqC1fwdpvhGRbsFNPdHL CncanFrbgnNo/UHSQk3rSaMldFmIamDifWyXwUzhZX/D43btUsvQcOo61VPfXquuA1 Licytn4KjyWSU0dNRYf26tXA7ogtfiq6epJ/k2fZfNEYspZrnXMM7V5zDTxTDso4d3 OLcxGpFbol6Cw== Received: from debian-rockchip-rock5b-rk3588.. (unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 247EE17E14DD; Fri, 5 Dec 2025 10:12:25 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 04/10] drm/gem: Add huge tmpfs mountpoint helpers Date: Fri, 5 Dec 2025 10:12:10 +0100 Message-ID: <20251205091216.150968-5-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Add the drm_gem_huge_mnt_create() and drm_gem_get_huge_mnt() helpers to avoid code duplication in the i915, V3D, Panfrost and Panthor drivers. The former creates and mounts a dedicated huge tmpfs mountpoint, for the lifetime of a DRM device, used at GEM object initialization. The latter retrieves the dedicated huge tmpfs mountpoint used by a DRM device. The next commits will port drivers to these helpers. v3: - store huge tmpfs mountpoint in drm_device v4: - return 0 in builds with CONFIG_TRANSPARENT_HUGEPAGE=3Dn - return 0 when huge_mnt already exists - use new vfs_parse_fs_string() helper v5: - remove warning on !dev->huge_mnt and reset to NULL on free - inline drm_gem_huge_mnt_create() to remove func from text and avoid calls in builds with CONFIG_TRANSPARENT_HUGEPAGE=3Dn - compile out drm_device's huge_mnt field in builds with CONFIG_TRANSPARENT_HUGEPAGE=3Dn - add drm_gem_has_huge_mnt() helper v6: - move huge_mnt doc into ifdef'd section - either inline or export drm_gem_huge_mnt_create() v7: - include in drm_gem.h v9: - replace drm_gem_has_huge_mnt() by drm_gem_get_huge_mnt() v11: - doc fixes - add Boris and Ma=C3=ADra R-bs Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Boris Brezillon Reviewed-by: Ma=C3=ADra Canal --- drivers/gpu/drm/drm_gem.c | 57 +++++++++++++++++++++++++++++++++++++++ include/drm/drm_device.h | 15 +++++++++++ include/drm/drm_gem.h | 33 +++++++++++++++++++++++ 3 files changed, 105 insertions(+) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 933fc89dd648..32dddb23e211 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -29,6 +29,9 @@ #include #include #include +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#include +#endif #include #include #include @@ -82,6 +85,60 @@ * up at a later date, and as our interface with shmfs for memory allocati= on. */ =20 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +static void drm_gem_huge_mnt_free(struct drm_device *dev, void *data) +{ + kern_unmount(dev->huge_mnt); +} + +/** + * drm_gem_huge_mnt_create - Create, mount and use a huge tmpfs mountpoint + * @dev: DRM device that will use the huge tmpfs mountpoint + * @value: huge tmpfs mount option value + * + * This function creates and mounts a dedicated huge tmpfs mountpoint for = the + * lifetime of the DRM device @dev which is used at GEM object initializat= ion + * with drm_gem_object_init(). + * + * The most common option for @value is "within_size" which only allocates= huge + * pages if the page will be fully within the GEM object size. "always", + * "advise" and "never" are supported too but the latter would just create= a + * mountpoint similar to the default one (`shm_mnt`). See shmemfs and + * Transparent Hugepage for more information. + * + * Returns: + * 0 on success or a negative error code on failure. + */ +int drm_gem_huge_mnt_create(struct drm_device *dev, const char *value) +{ + struct file_system_type *type; + struct fs_context *fc; + int ret; + + if (unlikely(drm_gem_get_huge_mnt(dev))) + return 0; + + type =3D get_fs_type("tmpfs"); + if (unlikely(!type)) + return -EOPNOTSUPP; + fc =3D fs_context_for_mount(type, SB_KERNMOUNT); + if (IS_ERR(fc)) + return PTR_ERR(fc); + ret =3D vfs_parse_fs_string(fc, "source", "tmpfs"); + if (unlikely(ret)) + return -ENOPARAM; + ret =3D vfs_parse_fs_string(fc, "huge", value); + if (unlikely(ret)) + return -ENOPARAM; + + dev->huge_mnt =3D fc_mount_longterm(fc); + put_fs_context(fc); + + return drmm_add_action_or_reset(dev, drm_gem_huge_mnt_free, NULL); +} +EXPORT_SYMBOL_GPL(drm_gem_huge_mnt_create); +#endif + static void drm_gem_init_release(struct drm_device *dev, void *ptr) { diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h index 5af49c5c3778..bc78fb77cc27 100644 --- a/include/drm/drm_device.h +++ b/include/drm/drm_device.h @@ -3,6 +3,9 @@ =20 #include #include +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#include +#endif #include #include #include @@ -168,6 +171,18 @@ struct drm_device { */ struct drm_master *master; =20 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + /** + * @huge_mnt: + * + * Huge tmpfs mountpoint used at GEM object initialization + * drm_gem_object_init(). Drivers can call drm_gem_huge_mnt_create() to + * create, mount and use it. The default tmpfs mountpoint (`shm_mnt`) is + * used if NULL. + */ + struct vfsmount *huge_mnt; +#endif + /** * @driver_features: per-device driver features * diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 7c8bd67d087c..97b5fca8966d 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -40,6 +40,9 @@ #include #include =20 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +#include +#endif #include =20 struct iosys_map; @@ -492,6 +495,36 @@ struct drm_gem_object { DRM_GEM_FOPS,\ } =20 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +int drm_gem_huge_mnt_create(struct drm_device *dev, const char *value); +#else +static inline int drm_gem_huge_mnt_create(struct drm_device *dev, + const char *value) +{ + return 0; +} +#endif + +/** + * drm_gem_get_huge_mnt - Get the huge tmpfs mountpoint used by a DRM devi= ce + * @dev: DRM device + + * This function gets the huge tmpfs mountpoint used by DRM device @dev. A= huge + * tmpfs mountpoint is used instead of `shm_mnt` after a successful call to + * drm_gem_huge_mnt_create() when CONFIG_TRANSPARENT_HUGEPAGE is enabled. + + * Returns: + * The huge tmpfs mountpoint in use, NULL otherwise. + */ +static inline struct vfsmount *drm_gem_get_huge_mnt(struct drm_device *dev) +{ +#ifdef CONFIG_TRANSPARENT_HUGEPAGE + return dev->huge_mnt; +#else + return NULL; +#endif +} + void drm_gem_object_release(struct drm_gem_object *obj); void drm_gem_object_free(struct kref *kref); int drm_gem_object_init(struct drm_device *dev, --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA43C33A029; Fri, 5 Dec 2025 09:12:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925965; cv=none; b=ltXBKNhE+pwCWHlSfkpp2jbJ0Ss8Q5EOunLBbBFOb5gOeRPUrem/L7IzKDc3ObkNQo69xDCwVCvbyuxEG/2CPuosk75o1A9QH9cGnAi6QZMTs28jHJrG+LuhN8vQwazHwsXa6bC1un7xbEZNnfANUolw3s8efvD9NCzZhx0ossA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925965; c=relaxed/simple; bh=eBqeFd4tGfaL/+oYaUWVSEWVdybaswBZMMYqwL76/us=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Ii5uuBwbQEYFh+FSHqbIaCJHEakL2t4s4LO1LLTb5avOn210uRChrAHjP9OjUO5DA9BMdR3Eiygn4rzMNkyNJLcLrrzeT9ZPtbYao1c57ISYrCYxSk2mrw1V57XqJ2ycHSbrW5na8FXcUZdI/NUMydr3XlqCPCfHTChOVrtlQhQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=NnLz+S/Q; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="NnLz+S/Q" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1764925947; bh=eBqeFd4tGfaL/+oYaUWVSEWVdybaswBZMMYqwL76/us=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NnLz+S/Qxby2WZzVfVo1Oa+jC3KIjaZkdMlCnUQv+Br0EbOdwebDvowqTe+tR8/9O OmDPE7VzXtH5HAlRoXYSV/j4Opru4M8YzY9xRZJ3Eu9p7U9+ZBCHFE5PLjOHy6gC0v Ki9Q9/o+72OcLUUfsLw39ZzCNpGQXoCPwI3aa1Tu8Tuu/7lKPUhVFDPIJqbHKcPa75 iMMEvGEtJ8xbnPgOT1/xBcuJFUPQMFIyRuFkWViZ5iIBhrDHz6zBdwYXAMQWwHz4up cIWEvTazgWSB7u227xx9RIwIMnGz1njRDdLIi5NM9e7P7BUheK+tgDT55k++GHSo3J y1FvYeBZVqnmw== Received: from debian-rockchip-rock5b-rk3588.. (unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 277E817E1572; Fri, 5 Dec 2025 10:12:26 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 05/10] drm/i915: Use huge tmpfs mountpoint helpers Date: Fri, 5 Dec 2025 10:12:11 +0100 Message-ID: <20251205091216.150968-6-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Make use of the new drm_gem_huge_mnt_create() and drm_gem_get_huge_mnt() helpers to avoid code duplication. Now that it's just a few lines long, the single function in i915_gemfs.c is moved into i915_gem_shmem.c. v3: - use huge tmpfs mountpoint in drm_device - move i915_gemfs.c into i915_gem_shmem.c v4: - clean up mountpoint creation error handling v5: - use drm_gem_has_huge_mnt() helper v7: - include in i915_gem_shmem.c v8: - keep logging notice message with CONFIG_TRANSPARENT_HUGEPAGE=3Dn - don't access huge_mnt field with CONFIG_TRANSPARENT_HUGEPAGE=3Dn v9: - replace drm_gem_has_huge_mnt() by drm_gem_get_huge_mnt() - remove useless ternary op test in selftests/huge_pages.c v12: - fix layering violation in selftests (Tvrtko) - fix incorrect filename in commit message Signed-off-by: Lo=C3=AFc Molinari --- drivers/gpu/drm/i915/Makefile | 3 +- .../gpu/drm/i915/gem/i915_gem_object_types.h | 9 +-- drivers/gpu/drm/i915/gem/i915_gem_shmem.c | 58 ++++++++++----- drivers/gpu/drm/i915/gem/i915_gemfs.c | 71 ------------------- drivers/gpu/drm/i915/gem/i915_gemfs.h | 14 ---- .../gpu/drm/i915/gem/selftests/huge_pages.c | 15 +--- drivers/gpu/drm/i915/i915_drv.h | 5 -- 7 files changed, 50 insertions(+), 125 deletions(-) delete mode 100644 drivers/gpu/drm/i915/gem/i915_gemfs.c delete mode 100644 drivers/gpu/drm/i915/gem/i915_gemfs.h diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile index 84ec79b64960..b5a8c0a6b747 100644 --- a/drivers/gpu/drm/i915/Makefile +++ b/drivers/gpu/drm/i915/Makefile @@ -169,8 +169,7 @@ gem-y +=3D \ gem/i915_gem_ttm_move.o \ gem/i915_gem_ttm_pm.o \ gem/i915_gem_userptr.o \ - gem/i915_gem_wait.o \ - gem/i915_gemfs.o + gem/i915_gem_wait.o i915-y +=3D \ $(gem-y) \ i915_active.o \ diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu= /drm/i915/gem/i915_gem_object_types.h index 64600aa8227f..f94409e8ec4c 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h @@ -348,12 +348,13 @@ struct drm_i915_gem_object { */ #define I915_BO_ALLOC_GPU_ONLY BIT(6) #define I915_BO_ALLOC_CCS_AUX BIT(7) +#define I915_BO_ALLOC_NOTHP BIT(8) /* * Object is allowed to retain its initial data and will not be cleared on= first * access if used along with I915_BO_ALLOC_USER. This is mainly to keep * preallocated framebuffer data intact while transitioning it to i915drmf= b. */ -#define I915_BO_PREALLOC BIT(8) +#define I915_BO_PREALLOC BIT(9) #define I915_BO_ALLOC_FLAGS (I915_BO_ALLOC_CONTIGUOUS | \ I915_BO_ALLOC_VOLATILE | \ I915_BO_ALLOC_CPU_CLEAR | \ @@ -363,9 +364,9 @@ struct drm_i915_gem_object { I915_BO_ALLOC_GPU_ONLY | \ I915_BO_ALLOC_CCS_AUX | \ I915_BO_PREALLOC) -#define I915_BO_READONLY BIT(9) -#define I915_TILING_QUIRK_BIT 10 /* unknown swizzling; do not release!= */ -#define I915_BO_PROTECTED BIT(11) +#define I915_BO_READONLY BIT(10) +#define I915_TILING_QUIRK_BIT 11 /* unknown swizzling; do not release!= */ +#define I915_BO_PROTECTED BIT(12) /** * @mem_flags - Mutable placement-related flags * diff --git a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c b/drivers/gpu/drm/i9= 15/gem/i915_gem_shmem.c index 26dda55a07ff..6ad1d6f99363 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_shmem.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_shmem.c @@ -9,14 +9,16 @@ #include =20 #include +#include +#include =20 #include "gem/i915_gem_region.h" #include "i915_drv.h" #include "i915_gem_object.h" #include "i915_gem_tiling.h" -#include "i915_gemfs.h" #include "i915_scatterlist.h" #include "i915_trace.h" +#include "i915_utils.h" =20 /* * Move folios to appropriate lru and release the batch, decrementing the @@ -494,9 +496,11 @@ const struct drm_i915_gem_object_ops i915_gem_shmem_op= s =3D { =20 static int __create_shmem(struct drm_i915_private *i915, struct drm_gem_object *obj, - resource_size_t size) + resource_size_t size, + unsigned int flags) { - unsigned long flags =3D VM_NORESERVE; + unsigned long shmem_flags =3D VM_NORESERVE; + struct vfsmount *huge_mnt; struct file *filp; =20 drm_gem_private_object_init(&i915->drm, obj, size); @@ -515,11 +519,12 @@ static int __create_shmem(struct drm_i915_private *i9= 15, if (BITS_PER_LONG =3D=3D 64 && size > MAX_LFS_FILESIZE) return -E2BIG; =20 - if (i915->mm.gemfs) - filp =3D shmem_file_setup_with_mnt(i915->mm.gemfs, "i915", size, - flags); + huge_mnt =3D drm_gem_get_huge_mnt(&i915->drm); + if (!(flags & I915_BO_ALLOC_NOTHP) && huge_mnt) + filp =3D shmem_file_setup_with_mnt(huge_mnt, "i915", size, + shmem_flags); else - filp =3D shmem_file_setup("i915", size, flags); + filp =3D shmem_file_setup("i915", size, shmem_flags); if (IS_ERR(filp)) return PTR_ERR(filp); =20 @@ -548,7 +553,7 @@ static int shmem_object_init(struct intel_memory_region= *mem, gfp_t mask; int ret; =20 - ret =3D __create_shmem(i915, &obj->base, size); + ret =3D __create_shmem(i915, &obj->base, size, flags); if (ret) return ret; =20 @@ -644,21 +649,40 @@ i915_gem_object_create_shmem_from_data(struct drm_i91= 5_private *i915, =20 static int init_shmem(struct intel_memory_region *mem) { - i915_gemfs_init(mem->i915); - intel_memory_region_set_name(mem, "system"); + struct drm_i915_private *i915 =3D mem->i915; =20 - return 0; /* We have fallback to the kernel mnt if gemfs init failed. */ -} + /* + * By creating our own shmemfs mountpoint, we can pass in + * mount flags that better match our usecase. + * + * One example, although it is probably better with a per-file + * control, is selecting huge page allocations ("huge=3Dwithin_size"). + * However, we only do so on platforms which benefit from it, or to + * offset the overhead of iommu lookups, where with latter it is a net + * win even on platforms which would otherwise see some performance + * regressions such a slow reads issue on Broadwell and Skylake. + */ =20 -static int release_shmem(struct intel_memory_region *mem) -{ - i915_gemfs_fini(mem->i915); - return 0; + if (GRAPHICS_VER(i915) < 11 && !i915_vtd_active(i915)) + goto no_thp; + + drm_gem_huge_mnt_create(&i915->drm, "within_size"); + if (drm_gem_get_huge_mnt(&i915->drm)) + drm_info(&i915->drm, "Using Transparent Hugepages\n"); + else + drm_notice(&i915->drm, + "Transparent Hugepage support is recommended for optimal performance= %s\n", + GRAPHICS_VER(i915) >=3D 11 ? " on this platform!" : + " when IOMMU is enabled!"); + + no_thp: + intel_memory_region_set_name(mem, "system"); + + return 0; /* We have fallback to the kernel mnt if huge mnt failed. */ } =20 static const struct intel_memory_region_ops shmem_region_ops =3D { .init =3D init_shmem, - .release =3D release_shmem, .init_object =3D shmem_object_init, }; =20 diff --git a/drivers/gpu/drm/i915/gem/i915_gemfs.c b/drivers/gpu/drm/i915/g= em/i915_gemfs.c deleted file mode 100644 index 1f1290214031..000000000000 --- a/drivers/gpu/drm/i915/gem/i915_gemfs.c +++ /dev/null @@ -1,71 +0,0 @@ -// SPDX-License-Identifier: MIT -/* - * Copyright =C2=A9 2017 Intel Corporation - */ - -#include -#include -#include - -#include - -#include "i915_drv.h" -#include "i915_gemfs.h" -#include "i915_utils.h" - -void i915_gemfs_init(struct drm_i915_private *i915) -{ - struct file_system_type *type; - struct fs_context *fc; - struct vfsmount *gemfs; - int ret; - - /* - * By creating our own shmemfs mountpoint, we can pass in - * mount flags that better match our usecase. - * - * One example, although it is probably better with a per-file - * control, is selecting huge page allocations ("huge=3Dwithin_size"). - * However, we only do so on platforms which benefit from it, or to - * offset the overhead of iommu lookups, where with latter it is a net - * win even on platforms which would otherwise see some performance - * regressions such a slow reads issue on Broadwell and Skylake. - */ - - if (GRAPHICS_VER(i915) < 11 && !i915_vtd_active(i915)) - return; - - if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) - goto err; - - type =3D get_fs_type("tmpfs"); - if (!type) - goto err; - - fc =3D fs_context_for_mount(type, SB_KERNMOUNT); - if (IS_ERR(fc)) - goto err; - ret =3D vfs_parse_fs_string(fc, "source", "tmpfs"); - if (!ret) - ret =3D vfs_parse_fs_string(fc, "huge", "within_size"); - if (!ret) - gemfs =3D fc_mount_longterm(fc); - put_fs_context(fc); - if (ret) - goto err; - - i915->mm.gemfs =3D gemfs; - drm_info(&i915->drm, "Using Transparent Hugepages\n"); - return; - -err: - drm_notice(&i915->drm, - "Transparent Hugepage support is recommended for optimal performance%= s\n", - GRAPHICS_VER(i915) >=3D 11 ? " on this platform!" : - " when IOMMU is enabled!"); -} - -void i915_gemfs_fini(struct drm_i915_private *i915) -{ - kern_unmount(i915->mm.gemfs); -} diff --git a/drivers/gpu/drm/i915/gem/i915_gemfs.h b/drivers/gpu/drm/i915/g= em/i915_gemfs.h deleted file mode 100644 index 16d4333c9a4e..000000000000 --- a/drivers/gpu/drm/i915/gem/i915_gemfs.h +++ /dev/null @@ -1,14 +0,0 @@ -/* SPDX-License-Identifier: MIT */ -/* - * Copyright =C2=A9 2017 Intel Corporation - */ - -#ifndef __I915_GEMFS_H__ -#define __I915_GEMFS_H__ - -struct drm_i915_private; - -void i915_gemfs_init(struct drm_i915_private *i915); -void i915_gemfs_fini(struct drm_i915_private *i915); - -#endif diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c b/drivers/gpu/= drm/i915/gem/selftests/huge_pages.c index bd08605a1611..02e9bf87f654 100644 --- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c +++ b/drivers/gpu/drm/i915/gem/selftests/huge_pages.c @@ -1316,7 +1316,7 @@ typedef struct drm_i915_gem_object * =20 static inline bool igt_can_allocate_thp(struct drm_i915_private *i915) { - return i915->mm.gemfs && has_transparent_hugepage(); + return !!drm_gem_get_huge_mnt(&i915->drm); } =20 static struct drm_i915_gem_object * @@ -1761,7 +1761,6 @@ static int igt_tmpfs_fallback(void *arg) struct drm_i915_private *i915 =3D arg; struct i915_address_space *vm; struct i915_gem_context *ctx; - struct vfsmount *gemfs =3D i915->mm.gemfs; struct drm_i915_gem_object *obj; struct i915_vma *vma; struct file *file; @@ -1779,15 +1778,8 @@ static int igt_tmpfs_fallback(void *arg) } vm =3D i915_gem_context_get_eb_vm(ctx); =20 - /* - * Make sure that we don't burst into a ball of flames upon falling back - * to tmpfs, which we rely on if on the off-chance we encounter a failure - * when setting up gemfs. - */ - - i915->mm.gemfs =3D NULL; - - obj =3D i915_gem_object_create_shmem(i915, PAGE_SIZE); + obj =3D i915_gem_object_create_region(i915->mm.regions[INTEL_REGION_SMEM], + PAGE_SIZE, 0, I915_BO_ALLOC_NOTHP); if (IS_ERR(obj)) { err =3D PTR_ERR(obj); goto out_restore; @@ -1819,7 +1811,6 @@ static int igt_tmpfs_fallback(void *arg) out_put: i915_gem_object_put(obj); out_restore: - i915->mm.gemfs =3D gemfs; =20 i915_vm_put(vm); out: diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_dr= v.h index 95f9ddf22ce4..93a5af3de334 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -141,11 +141,6 @@ struct i915_gem_mm { */ atomic_t free_count; =20 - /** - * tmpfs instance used for shmem backed objects - */ - struct vfsmount *gemfs; - struct intel_memory_region *regions[INTEL_REGION_UNKNOWN]; =20 struct notifier_block oom_notifier; --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DB92C3370E5; Fri, 5 Dec 2025 09:12:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925957; cv=none; b=j32rLw5oAPQiOp5KU6GSM6Q/ssr7bI1LWAmYMA0rbIK4kYZpE8/0a0mtPCSEQCl8pD9bssktwbqzQC2X3EJ+HJUd7Kh6BLWGXHeVJ2TaAjSnuCSsX7BVh+dm7GnAuSXPn61hR8+JGhLWzjz8d+NWhbMCVr7gJ3zxkAAXVfFXV7o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925957; c=relaxed/simple; bh=EuOrtawPFONPLL/kLdWEf7FrwFEddCnrCOFPNp5/XKw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=GuDDZeOktIutPHG+9VNgJ/ohsCmD2WuzsCN41Z7TTy3x3lScTCsTIKdETpvo3AnFcDzqdPIvDTTeZN6D5+O8Xbc+CHc0b5AcZwrJ93zim8KGqLHBY4YsdA9wk5pIUHuCCIGQ65VNxnGt+M0H2MJKF5l11ypRUg+6JTK7fsWqgAY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=kxhJMusO; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="kxhJMusO" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1764925948; bh=EuOrtawPFONPLL/kLdWEf7FrwFEddCnrCOFPNp5/XKw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kxhJMusOjBkWoK3Svro3fDI5dbMSxWAHqZddc69/Y1DQ2XiqzarnrygiHs3IrcbuK IN4vgWwl0Hyim8ssS/TXeQhHfA55PDMBeWg2zAVpQTdI6i1mLVzv2gje3XLKKQUUOV AjBFso7HOBpAEI2K6pek8F3ytEbs1HB5TWVDtjWqXDHH6YwG0fJhj+oRtYJWix+rxL iG9nC68CDblYKAaW6ohTDNvb6sKpaGN5RiMeBEor67oF0/T0Dnbm1Q2ZiuxCQ/52wd YYNkfv7JzOgwYycrFj3rWRt/i3CjTx+35f5iOERLgwd6X//Bwz42zbsR+KlUFfT2jm t1i4cTjnYsHkQ== Received: from debian-rockchip-rock5b-rk3588.. (unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 3255F17E35CF; Fri, 5 Dec 2025 10:12:27 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 06/10] drm/v3d: Use huge tmpfs mountpoint helpers Date: Fri, 5 Dec 2025 10:12:12 +0100 Message-ID: <20251205091216.150968-7-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Make use of the new drm_gem_huge_mnt_create() and drm_gem_get_huge_mnt() helpers to avoid code duplication. Now that it's just a few lines long, the single function in v3d_gemfs.c is moved into v3d_gem.c. v3: - use huge tmpfs mountpoint in drm_device - move v3d_gemfs.c into v3d_gem.c v4: - clean up mountpoint creation error handling v5: - fix CONFIG_TRANSPARENT_HUGEPAGE check - use drm_gem_has_huge_mnt() helper v8: - don't access huge_mnt field with CONFIG_TRANSPARENT_HUGEPAGE=3Dn v9: - replace drm_gem_has_huge_mnt() by drm_gem_get_huge_mnt() v10: - get rid of CONFIG_TRANSPARENT_HUGEPAGE ifdefs v11: - remove superfluous comment - add Ma=C3=ADra and Boris R-bs Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Ma=C3=ADra Canal Reviewed-by: Boris Brezillon --- drivers/gpu/drm/v3d/Makefile | 3 +- drivers/gpu/drm/v3d/v3d_bo.c | 5 ++- drivers/gpu/drm/v3d/v3d_drv.c | 2 +- drivers/gpu/drm/v3d/v3d_drv.h | 11 +----- drivers/gpu/drm/v3d/v3d_gem.c | 21 +++++++++-- drivers/gpu/drm/v3d/v3d_gemfs.c | 62 --------------------------------- 6 files changed, 24 insertions(+), 80 deletions(-) delete mode 100644 drivers/gpu/drm/v3d/v3d_gemfs.c diff --git a/drivers/gpu/drm/v3d/Makefile b/drivers/gpu/drm/v3d/Makefile index fcf710926057..b7d673f1153b 100644 --- a/drivers/gpu/drm/v3d/Makefile +++ b/drivers/gpu/drm/v3d/Makefile @@ -13,8 +13,7 @@ v3d-y :=3D \ v3d_trace_points.o \ v3d_sched.o \ v3d_sysfs.o \ - v3d_submit.o \ - v3d_gemfs.o + v3d_submit.o =20 v3d-$(CONFIG_DEBUG_FS) +=3D v3d_debugfs.o =20 diff --git a/drivers/gpu/drm/v3d/v3d_bo.c b/drivers/gpu/drm/v3d/v3d_bo.c index d9547f5117b9..3ee8d9c36d92 100644 --- a/drivers/gpu/drm/v3d/v3d_bo.c +++ b/drivers/gpu/drm/v3d/v3d_bo.c @@ -114,7 +114,7 @@ v3d_bo_create_finish(struct drm_gem_object *obj) if (IS_ERR(sgt)) return PTR_ERR(sgt); =20 - if (!v3d->gemfs) + if (!drm_gem_get_huge_mnt(obj->dev)) align =3D SZ_4K; else if (obj->size >=3D SZ_1M) align =3D SZ_1M; @@ -150,12 +150,11 @@ struct v3d_bo *v3d_bo_create(struct drm_device *dev, = struct drm_file *file_priv, size_t unaligned_size) { struct drm_gem_shmem_object *shmem_obj; - struct v3d_dev *v3d =3D to_v3d_dev(dev); struct v3d_bo *bo; int ret; =20 shmem_obj =3D drm_gem_shmem_create_with_mnt(dev, unaligned_size, - v3d->gemfs); + drm_gem_get_huge_mnt(dev)); if (IS_ERR(shmem_obj)) return ERR_CAST(shmem_obj); bo =3D to_v3d_bo(&shmem_obj->base); diff --git a/drivers/gpu/drm/v3d/v3d_drv.c b/drivers/gpu/drm/v3d/v3d_drv.c index e8a46c8bad8a..8faa9382846f 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.c +++ b/drivers/gpu/drm/v3d/v3d_drv.c @@ -107,7 +107,7 @@ static int v3d_get_param_ioctl(struct drm_device *dev, = void *data, args->value =3D v3d->perfmon_info.max_counters; return 0; case DRM_V3D_PARAM_SUPPORTS_SUPER_PAGES: - args->value =3D !!v3d->gemfs; + args->value =3D !!drm_gem_get_huge_mnt(dev); return 0; case DRM_V3D_PARAM_GLOBAL_RESET_COUNTER: mutex_lock(&v3d->reset_lock); diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h index 1884686985b8..99a39329bb85 100644 --- a/drivers/gpu/drm/v3d/v3d_drv.h +++ b/drivers/gpu/drm/v3d/v3d_drv.h @@ -158,11 +158,6 @@ struct v3d_dev { struct drm_mm mm; spinlock_t mm_lock; =20 - /* - * tmpfs instance used for shmem backed objects - */ - struct vfsmount *gemfs; - struct work_struct overflow_mem_work; =20 struct v3d_queue_state queue[V3D_MAX_QUEUES]; @@ -569,6 +564,7 @@ extern const struct dma_fence_ops v3d_fence_ops; struct dma_fence *v3d_fence_create(struct v3d_dev *v3d, enum v3d_queue q); =20 /* v3d_gem.c */ +extern bool super_pages; int v3d_gem_init(struct drm_device *dev); void v3d_gem_destroy(struct drm_device *dev); void v3d_reset_sms(struct v3d_dev *v3d); @@ -576,11 +572,6 @@ void v3d_reset(struct v3d_dev *v3d); void v3d_invalidate_caches(struct v3d_dev *v3d); void v3d_clean_caches(struct v3d_dev *v3d); =20 -/* v3d_gemfs.c */ -extern bool super_pages; -void v3d_gemfs_init(struct v3d_dev *v3d); -void v3d_gemfs_fini(struct v3d_dev *v3d); - /* v3d_submit.c */ void v3d_job_cleanup(struct v3d_job *job); void v3d_job_put(struct v3d_job *job); diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c index 5a180dc6c452..697b0b3ca92c 100644 --- a/drivers/gpu/drm/v3d/v3d_gem.c +++ b/drivers/gpu/drm/v3d/v3d_gem.c @@ -259,6 +259,24 @@ v3d_invalidate_caches(struct v3d_dev *v3d) v3d_invalidate_slices(v3d, 0); } =20 +static void +v3d_huge_mnt_init(struct v3d_dev *v3d) +{ + int err =3D 0; + + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && super_pages) + err =3D drm_gem_huge_mnt_create(&v3d->drm, "within_size"); + + if (drm_gem_get_huge_mnt(&v3d->drm)) + drm_info(&v3d->drm, "Using Transparent Hugepages\n"); + else if (err) + drm_warn(&v3d->drm, "Can't use Transparent Hugepages (%d)\n", + err); + else + drm_notice(&v3d->drm, + "Transparent Hugepage support is recommended for optimal performance= on this platform!\n"); +} + int v3d_gem_init(struct drm_device *dev) { @@ -310,7 +328,7 @@ v3d_gem_init(struct drm_device *dev) v3d_init_hw_state(v3d); v3d_mmu_set_page_table(v3d); =20 - v3d_gemfs_init(v3d); + v3d_huge_mnt_init(v3d); =20 ret =3D v3d_sched_init(v3d); if (ret) { @@ -330,7 +348,6 @@ v3d_gem_destroy(struct drm_device *dev) enum v3d_queue q; =20 v3d_sched_fini(v3d); - v3d_gemfs_fini(v3d); =20 /* Waiting for jobs to finish would need to be done before * unregistering V3D. diff --git a/drivers/gpu/drm/v3d/v3d_gemfs.c b/drivers/gpu/drm/v3d/v3d_gemf= s.c deleted file mode 100644 index bf351fc0d488..000000000000 --- a/drivers/gpu/drm/v3d/v3d_gemfs.c +++ /dev/null @@ -1,62 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* Copyright (C) 2024 Raspberry Pi */ - -#include -#include -#include - -#include - -#include "v3d_drv.h" - -void v3d_gemfs_init(struct v3d_dev *v3d) -{ - struct file_system_type *type; - struct fs_context *fc; - struct vfsmount *gemfs; - int ret; - - /* - * By creating our own shmemfs mountpoint, we can pass in - * mount flags that better match our usecase. However, we - * only do so on platforms which benefit from it. - */ - if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) - goto err; - - /* The user doesn't want to enable Super Pages */ - if (!super_pages) - goto err; - - type =3D get_fs_type("tmpfs"); - if (!type) - goto err; - - fc =3D fs_context_for_mount(type, SB_KERNMOUNT); - if (IS_ERR(fc)) - goto err; - ret =3D vfs_parse_fs_string(fc, "source", "tmpfs"); - if (!ret) - ret =3D vfs_parse_fs_string(fc, "huge", "within_size"); - if (!ret) - gemfs =3D fc_mount_longterm(fc); - put_fs_context(fc); - if (ret) - goto err; - - v3d->gemfs =3D gemfs; - drm_info(&v3d->drm, "Using Transparent Hugepages\n"); - - return; - -err: - v3d->gemfs =3D NULL; - drm_notice(&v3d->drm, - "Transparent Hugepage support is recommended for optimal performance = on this platform!\n"); -} - -void v3d_gemfs_fini(struct v3d_dev *v3d) -{ - if (v3d->gemfs) - kern_unmount(v3d->gemfs); -} --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CB1AB337BBB; Fri, 5 Dec 2025 09:12:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925960; cv=none; b=s6gyQKkYXeigQiVDqkqkTSVdTQJmP/zC67aKcNlqkT57CQVo1OI0F8EyPQRC6QaCztO5qw6NPHXEn4Ivn2pTgHYCHbz6HwvBQn1+J5wPF15BrX1FDB0M5Ct5tyG9jN2nVytpoOFpZT0DEgsPBJcPmOFtrxXWaKh2aOumNEdZYxQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925960; c=relaxed/simple; bh=Zex2NKxNRl6ia1F7pINdtc/8BVAWXVoWCqYCGqXTtRw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=jdZkPnVMGc/64wXCWv796jcQ5iD0aIuAnqzD4CZvZ0PM8gh4obAvOBrNpzWbDQTsQw/+qvf7TLAd89pcanfRpt1tlPr6HkqEGUg590gODQYW4tZIkMUQKUzB5AXisAiEczRSOV1r6/1a9RtrtshUdoN1h9Tzz1gkKsp0s0jFFLk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=B0O8Ct9y; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="B0O8Ct9y" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1764925949; bh=Zex2NKxNRl6ia1F7pINdtc/8BVAWXVoWCqYCGqXTtRw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B0O8Ct9yxpHDt9iBZpzzu+4ZxNC2XuEDs5BfTgI8X3WApjaTp5S8XVvzpWoWM5JdB CWQTW7YroM2QB+FWy5qUvyX78cL1PJmhc2kixKIf40HzOm0J3uHwB8QgF4uHr4cMW8 Fsf51VAsQ/B5bomUuZHJpTZjl6pzGV3fwNBQeK8PwMZbvhgWqSOYx9aqhag7kI4S6Y am54+3UMIuGRF9nIw4iNLIQzD5XBxtA8yJEIAuutdRN+JXO0KGKIktThj7Tzp+R6KG /ozpOH9rQl2jIPi+dN9rnt0Q1qiwgtojSUOyZok5B3sBbVn/8i/VfgrRKEADBrLlbs B2hWcVTY6SG8A== Received: from debian-rockchip-rock5b-rk3588.. (unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 3C95D17E3656; Fri, 5 Dec 2025 10:12:28 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 07/10] drm/gem: Get rid of *_with_mnt helpers Date: Fri, 5 Dec 2025 10:12:13 +0100 Message-ID: <20251205091216.150968-8-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable drm_gem_object_init_with_mnt() and drm_gem_shmem_create_with_mnt() can be removed now that the drivers use the new drm_gem_huge_mnt_create() and drm_gem_get_huge_mnt() helpers. v5: - use drm_gem_has_huge_mnt() helper - compile out shmem_file_setup_with_mnt() call in builds with CONFIG_TRANSPARENT_HUGEPAGE=3Dn v9: - replace drm_gem_has_huge_mnt() with drm_gem_get_huge_mnt() Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Boris Brezillon --- drivers/gpu/drm/drm_gem.c | 37 +++++++------------------ drivers/gpu/drm/drm_gem_shmem_helper.c | 38 ++++++-------------------- drivers/gpu/drm/v3d/v3d_bo.c | 3 +- include/drm/drm_gem.h | 3 -- include/drm/drm_gem_shmem_helper.h | 3 -- 5 files changed, 19 insertions(+), 65 deletions(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 32dddb23e211..6021c4087a08 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -171,29 +171,28 @@ drm_gem_init(struct drm_device *dev) } =20 /** - * drm_gem_object_init_with_mnt - initialize an allocated shmem-backed GEM - * object in a given shmfs mountpoint + * drm_gem_object_init - initialize an allocated shmem-backed GEM object * * @dev: drm_device the object should be initialized for * @obj: drm_gem_object to initialize * @size: object size - * @gemfs: tmpfs mount where the GEM object will be created. If NULL, use - * the usual tmpfs mountpoint (`shm_mnt`). * * Initialize an already allocated GEM object of the specified size with - * shmfs backing store. + * shmfs backing store. A huge mountpoint can be used by calling + * drm_gem_huge_mnt_create() beforehand. */ -int drm_gem_object_init_with_mnt(struct drm_device *dev, - struct drm_gem_object *obj, size_t size, - struct vfsmount *gemfs) +int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, + size_t size) { + struct vfsmount *huge_mnt; struct file *filp; =20 drm_gem_private_object_init(dev, obj, size); =20 - if (gemfs) - filp =3D shmem_file_setup_with_mnt(gemfs, "drm mm object", size, - VM_NORESERVE); + huge_mnt =3D drm_gem_get_huge_mnt(dev); + if (huge_mnt) + filp =3D shmem_file_setup_with_mnt(huge_mnt, "drm mm object", + size, VM_NORESERVE); else filp =3D shmem_file_setup("drm mm object", size, VM_NORESERVE); =20 @@ -204,22 +203,6 @@ int drm_gem_object_init_with_mnt(struct drm_device *de= v, =20 return 0; } -EXPORT_SYMBOL(drm_gem_object_init_with_mnt); - -/** - * drm_gem_object_init - initialize an allocated shmem-backed GEM object - * @dev: drm_device the object should be initialized for - * @obj: drm_gem_object to initialize - * @size: object size - * - * Initialize an already allocated GEM object of the specified size with - * shmfs backing store. - */ -int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, - size_t size) -{ - return drm_gem_object_init_with_mnt(dev, obj, size, NULL); -} EXPORT_SYMBOL(drm_gem_object_init); =20 /** diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_g= em_shmem_helper.c index e67216cbb469..f8bcd1b0eb32 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -50,7 +50,7 @@ static const struct drm_gem_object_funcs drm_gem_shmem_fu= ncs =3D { }; =20 static int __drm_gem_shmem_init(struct drm_device *dev, struct drm_gem_shm= em_object *shmem, - size_t size, bool private, struct vfsmount *gemfs) + size_t size, bool private) { struct drm_gem_object *obj =3D &shmem->base; int ret =3D 0; @@ -62,7 +62,7 @@ static int __drm_gem_shmem_init(struct drm_device *dev, s= truct drm_gem_shmem_obj drm_gem_private_object_init(dev, obj, size); shmem->map_wc =3D false; /* dma-buf mappings use always writecombine */ } else { - ret =3D drm_gem_object_init_with_mnt(dev, obj, size, gemfs); + ret =3D drm_gem_object_init(dev, obj, size); } if (ret) { drm_gem_private_object_fini(obj); @@ -103,13 +103,12 @@ static int __drm_gem_shmem_init(struct drm_device *de= v, struct drm_gem_shmem_obj */ int drm_gem_shmem_init(struct drm_device *dev, struct drm_gem_shmem_object= *shmem, size_t size) { - return __drm_gem_shmem_init(dev, shmem, size, false, NULL); + return __drm_gem_shmem_init(dev, shmem, size, false); } EXPORT_SYMBOL_GPL(drm_gem_shmem_init); =20 static struct drm_gem_shmem_object * -__drm_gem_shmem_create(struct drm_device *dev, size_t size, bool private, - struct vfsmount *gemfs) +__drm_gem_shmem_create(struct drm_device *dev, size_t size, bool private) { struct drm_gem_shmem_object *shmem; struct drm_gem_object *obj; @@ -129,7 +128,7 @@ __drm_gem_shmem_create(struct drm_device *dev, size_t s= ize, bool private, obj =3D &shmem->base; } =20 - ret =3D __drm_gem_shmem_init(dev, shmem, size, private, gemfs); + ret =3D __drm_gem_shmem_init(dev, shmem, size, private); if (ret) { kfree(obj); return ERR_PTR(ret); @@ -150,31 +149,10 @@ __drm_gem_shmem_create(struct drm_device *dev, size_t= size, bool private, */ struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, = size_t size) { - return __drm_gem_shmem_create(dev, size, false, NULL); + return __drm_gem_shmem_create(dev, size, false); } EXPORT_SYMBOL_GPL(drm_gem_shmem_create); =20 -/** - * drm_gem_shmem_create_with_mnt - Allocate an object with the given size = in a - * given mountpoint - * @dev: DRM device - * @size: Size of the object to allocate - * @gemfs: tmpfs mount where the GEM object will be created - * - * This function creates a shmem GEM object in a given tmpfs mountpoint. - * - * Returns: - * A struct drm_gem_shmem_object * on success or an ERR_PTR()-encoded nega= tive - * error code on failure. - */ -struct drm_gem_shmem_object *drm_gem_shmem_create_with_mnt(struct drm_devi= ce *dev, - size_t size, - struct vfsmount *gemfs) -{ - return __drm_gem_shmem_create(dev, size, false, gemfs); -} -EXPORT_SYMBOL_GPL(drm_gem_shmem_create_with_mnt); - /** * drm_gem_shmem_release - Release resources associated with a shmem GEM o= bject. * @shmem: shmem GEM object @@ -851,7 +829,7 @@ drm_gem_shmem_prime_import_sg_table(struct drm_device *= dev, size_t size =3D PAGE_ALIGN(attach->dmabuf->size); struct drm_gem_shmem_object *shmem; =20 - shmem =3D __drm_gem_shmem_create(dev, size, true, NULL); + shmem =3D __drm_gem_shmem_create(dev, size, true); if (IS_ERR(shmem)) return ERR_CAST(shmem); =20 @@ -899,7 +877,7 @@ struct drm_gem_object *drm_gem_shmem_prime_import_no_ma= p(struct drm_device *dev, =20 size =3D PAGE_ALIGN(attach->dmabuf->size); =20 - shmem =3D __drm_gem_shmem_create(dev, size, true, NULL); + shmem =3D __drm_gem_shmem_create(dev, size, true); if (IS_ERR(shmem)) { ret =3D PTR_ERR(shmem); goto fail_detach; diff --git a/drivers/gpu/drm/v3d/v3d_bo.c b/drivers/gpu/drm/v3d/v3d_bo.c index 3ee8d9c36d92..c4316b768b3d 100644 --- a/drivers/gpu/drm/v3d/v3d_bo.c +++ b/drivers/gpu/drm/v3d/v3d_bo.c @@ -153,8 +153,7 @@ struct v3d_bo *v3d_bo_create(struct drm_device *dev, st= ruct drm_file *file_priv, struct v3d_bo *bo; int ret; =20 - shmem_obj =3D drm_gem_shmem_create_with_mnt(dev, unaligned_size, - drm_gem_get_huge_mnt(dev)); + shmem_obj =3D drm_gem_shmem_create(dev, unaligned_size); if (IS_ERR(shmem_obj)) return ERR_CAST(shmem_obj); bo =3D to_v3d_bo(&shmem_obj->base); diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index 97b5fca8966d..cca815dc87f3 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -529,9 +529,6 @@ void drm_gem_object_release(struct drm_gem_object *obj); void drm_gem_object_free(struct kref *kref); int drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size); -int drm_gem_object_init_with_mnt(struct drm_device *dev, - struct drm_gem_object *obj, size_t size, - struct vfsmount *gemfs); void drm_gem_private_object_init(struct drm_device *dev, struct drm_gem_object *obj, size_t size); void drm_gem_private_object_fini(struct drm_gem_object *obj); diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem= _helper.h index 589f7bfe7506..6b6478f5ca24 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -109,9 +109,6 @@ struct drm_gem_shmem_object { =20 int drm_gem_shmem_init(struct drm_device *dev, struct drm_gem_shmem_object= *shmem, size_t size); struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, = size_t size); -struct drm_gem_shmem_object *drm_gem_shmem_create_with_mnt(struct drm_devi= ce *dev, - size_t size, - struct vfsmount *gemfs); void drm_gem_shmem_release(struct drm_gem_shmem_object *shmem); void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem); =20 --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 38C3932826F; Fri, 5 Dec 2025 09:12:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925965; cv=none; b=GPtQJy8bBLlj/pytgzAhdUnry693LBRhk4jtS4D40AayP/rZ9Al/WWbmq22haYTKs80zEJ3f2BwI1A5C50ar86iTVgbls/pi1UsXu7yJ+HfjTEyNMpPsyyztIvgYzi0adlTNz3MmTNyypPOeR35aWOwuYd8rYcA79iPOw9EzFqw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925965; c=relaxed/simple; bh=wOROUdGmrTopYn8Lks6qkkQ2zPA2SCtrzeNGfh6cEHk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; 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(unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 41CCE17E368E; Fri, 5 Dec 2025 10:12:29 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 08/10] drm/panthor: Introduce huge tmpfs mountpoint option Date: Fri, 5 Dec 2025 10:12:14 +0100 Message-ID: <20251205091216.150968-9-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Introduce the 'panthor.transparent_hugepage' boolean module parameter (false by default). When the parameter is set to true, a new tmpfs mountpoint is created and mounted using the 'huge=3Dwithin_size' option. It's then used at GEM object creation instead of the default 'shm_mnt' mountpoint in order to enable Transparent Hugepage (THP) for the object (without having to rely on a system wide parameter). v3: - use huge tmpfs mountpoint in drm_device v4: - fix builds with CONFIG_TRANSPARENT_HUGEPAGE=3Dn - clean up mountpoint creation error handling - print negative error value v5: - use drm_gem_has_huge_tmp() helper - get rid of CONFIG_TRANSPARENT_HUGEPAGE ifdefs v9: - replace drm_gem_has_huge_tmp() by drm_gem_get_huge_tmp() v11: - enable 'panthor.transparent_hugepage' by default Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Boris Brezillon --- drivers/gpu/drm/panthor/panthor_device.c | 3 +++ drivers/gpu/drm/panthor/panthor_drv.c | 7 +++++++ drivers/gpu/drm/panthor/panthor_drv.h | 9 +++++++++ drivers/gpu/drm/panthor/panthor_gem.c | 18 ++++++++++++++++++ drivers/gpu/drm/panthor/panthor_gem.h | 2 ++ 5 files changed, 39 insertions(+) create mode 100644 drivers/gpu/drm/panthor/panthor_drv.h diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/pan= thor/panthor_device.c index e133b1e0ad6d..2979ee0e52c2 100644 --- a/drivers/gpu/drm/panthor/panthor_device.c +++ b/drivers/gpu/drm/panthor/panthor_device.c @@ -18,6 +18,7 @@ #include "panthor_devfreq.h" #include "panthor_device.h" #include "panthor_fw.h" +#include "panthor_gem.h" #include "panthor_gpu.h" #include "panthor_hw.h" #include "panthor_mmu.h" @@ -294,6 +295,8 @@ int panthor_device_init(struct panthor_device *ptdev) if (ret) goto err_unplug_fw; =20 + panthor_gem_init(ptdev); + /* ~3 frames */ pm_runtime_set_autosuspend_delay(ptdev->base.dev, 50); pm_runtime_use_autosuspend(ptdev->base.dev); diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/pantho= r/panthor_drv.c index d1d4c50da5bf..0e7ab6f5ba89 100644 --- a/drivers/gpu/drm/panthor/panthor_drv.c +++ b/drivers/gpu/drm/panthor/panthor_drv.c @@ -1559,6 +1559,7 @@ static const struct file_operations panthor_drm_drive= r_fops =3D { .read =3D drm_read, .llseek =3D noop_llseek, .mmap =3D panthor_mmap, + .get_unmapped_area =3D drm_gem_get_unmapped_area, .show_fdinfo =3D drm_show_fdinfo, .fop_flags =3D FOP_UNSIGNED_OFFSET, }; @@ -1626,6 +1627,12 @@ static const struct drm_driver panthor_drm_driver = =3D { #endif }; =20 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +bool panthor_transparent_hugepage =3D true; +module_param_named(transparent_hugepage, panthor_transparent_hugepage, boo= l, 0400); +MODULE_PARM_DESC(transparent_hugepage, "Use a dedicated tmpfs mount point = with Transparent Hugepage enabled (true =3D default)"); +#endif + static int panthor_probe(struct platform_device *pdev) { struct panthor_device *ptdev; diff --git a/drivers/gpu/drm/panthor/panthor_drv.h b/drivers/gpu/drm/pantho= r/panthor_drv.h new file mode 100644 index 000000000000..79dccd289881 --- /dev/null +++ b/drivers/gpu/drm/panthor/panthor_drv.h @@ -0,0 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0 or MIT +/* Copyright 2025 Amazon.com, Inc. or its affiliates */ + +#ifndef __PANTHOR_DRV_H__ +#define __PANTHOR_DRV_H__ + +extern bool panthor_transparent_hugepage; + +#endif diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/pantho= r/panthor_gem.c index 10d255cccc09..7ae07a9bc996 100644 --- a/drivers/gpu/drm/panthor/panthor_gem.c +++ b/drivers/gpu/drm/panthor/panthor_gem.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 or MIT /* Copyright 2019 Linaro, Ltd, Rob Herring */ /* Copyright 2023 Collabora ltd. */ +/* Copyright 2025 Amazon.com, Inc. or its affiliates */ =20 #include #include @@ -12,10 +13,27 @@ #include =20 #include "panthor_device.h" +#include "panthor_drv.h" #include "panthor_fw.h" #include "panthor_gem.h" #include "panthor_mmu.h" =20 +void panthor_gem_init(struct panthor_device *ptdev) +{ + int err; + + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && + !panthor_transparent_hugepage) + return; + + err =3D drm_gem_huge_mnt_create(&ptdev->base, "within_size"); + if (drm_gem_get_huge_mnt(&ptdev->base)) + drm_info(&ptdev->base, "Using Transparent Hugepage\n"); + else if (err) + drm_warn(&ptdev->base, "Can't use Transparent Hugepage (%d)\n", + err); +} + #ifdef CONFIG_DEBUG_FS static void panthor_gem_debugfs_bo_init(struct panthor_gem_object *bo) { diff --git a/drivers/gpu/drm/panthor/panthor_gem.h b/drivers/gpu/drm/pantho= r/panthor_gem.h index 80c6e24112d0..2eefe9104e5e 100644 --- a/drivers/gpu/drm/panthor/panthor_gem.h +++ b/drivers/gpu/drm/panthor/panthor_gem.h @@ -136,6 +136,8 @@ struct panthor_gem_object *to_panthor_bo(struct drm_gem= _object *obj) return container_of(to_drm_gem_shmem_obj(obj), struct panthor_gem_object,= base); } =20 +void panthor_gem_init(struct panthor_device *ptdev); + struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, = size_t size); =20 int --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 640AA339708; 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(unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 48EC917E368F; Fri, 5 Dec 2025 10:12:30 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 09/10] drm/panfrost: Introduce huge tmpfs mountpoint option Date: Fri, 5 Dec 2025 10:12:15 +0100 Message-ID: <20251205091216.150968-10-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Introduce the 'panfrost.transparent_hugepage' boolean module parameter (false by default). When the parameter is set to true, a new tmpfs mountpoint is created and mounted using the 'huge=3Dwithin_size' option. It's then used at GEM object creation instead of the default 'shm_mnt' mountpoint in order to enable Transparent Hugepage (THP) for the object (without having to rely on a system wide parameter). v3: - use huge tmpfs mountpoint in drm_device v4: - fix builds with CONFIG_TRANSPARENT_HUGEPAGE=3Dn - clean up mountpoint creation error handling - print negative error value v5: - use drm_gem_has_huge_tmp() helper - get rid of CONFIG_TRANSPARENT_HUGEPAGE ifdefs v9: - replace drm_gem_has_huge_tmp() by drm_gem_get_huge_tmp() v11: - enable 'panfrost.transparent_hugepage' by default Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Boris Brezillon --- drivers/gpu/drm/panfrost/panfrost_device.c | 3 +++ drivers/gpu/drm/panfrost/panfrost_drv.c | 6 ++++++ drivers/gpu/drm/panfrost/panfrost_drv.h | 9 +++++++++ drivers/gpu/drm/panfrost/panfrost_gem.c | 18 ++++++++++++++++++ drivers/gpu/drm/panfrost/panfrost_gem.h | 2 ++ 5 files changed, 38 insertions(+) create mode 100644 drivers/gpu/drm/panfrost/panfrost_drv.h diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/p= anfrost/panfrost_device.c index c61b97af120c..dedc13e56631 100644 --- a/drivers/gpu/drm/panfrost/panfrost_device.c +++ b/drivers/gpu/drm/panfrost/panfrost_device.c @@ -12,6 +12,7 @@ #include "panfrost_device.h" #include "panfrost_devfreq.h" #include "panfrost_features.h" +#include "panfrost_gem.h" #include "panfrost_issues.h" #include "panfrost_gpu.h" #include "panfrost_job.h" @@ -267,6 +268,8 @@ int panfrost_device_init(struct panfrost_device *pfdev) if (err) goto out_job; =20 + panfrost_gem_init(pfdev); + return 0; out_job: panfrost_jm_fini(pfdev); diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panf= rost/panfrost_drv.c index 7d8c7c337606..4f5f19eda587 100644 --- a/drivers/gpu/drm/panfrost/panfrost_drv.c +++ b/drivers/gpu/drm/panfrost/panfrost_drv.c @@ -858,6 +858,12 @@ static const struct drm_driver panfrost_drm_driver =3D= { #endif }; =20 +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +bool panfrost_transparent_hugepage =3D true; +module_param_named(transparent_hugepage, panfrost_transparent_hugepage, bo= ol, 0400); +MODULE_PARM_DESC(transparent_hugepage, "Use a dedicated tmpfs mount point = with Transparent Hugepage enabled (true =3D default)"); +#endif + static int panfrost_probe(struct platform_device *pdev) { struct panfrost_device *pfdev; diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.h b/drivers/gpu/drm/panf= rost/panfrost_drv.h new file mode 100644 index 000000000000..edeb093eb6da --- /dev/null +++ b/drivers/gpu/drm/panfrost/panfrost_drv.h @@ -0,0 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0 or MIT +/* Copyright 2025 Amazon.com, Inc. or its affiliates */ + +#ifndef __PANFROST_DRV_H__ +#define __PANFROST_DRV_H__ + +extern bool panfrost_transparent_hugepage; + +#endif diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.c b/drivers/gpu/drm/panf= rost/panfrost_gem.c index 8041b65c6609..c1688a542ec2 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem.c +++ b/drivers/gpu/drm/panfrost/panfrost_gem.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright 2019 Linaro, Ltd, Rob Herring */ +/* Copyright 2025 Amazon.com, Inc. or its affiliates */ =20 #include #include @@ -10,9 +11,26 @@ #include #include #include "panfrost_device.h" +#include "panfrost_drv.h" #include "panfrost_gem.h" #include "panfrost_mmu.h" =20 +void panfrost_gem_init(struct panfrost_device *pfdev) +{ + int err; + + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && + !panfrost_transparent_hugepage) + return; + + err =3D drm_gem_huge_mnt_create(&pfdev->base, "within_size"); + if (drm_gem_get_huge_mnt(&pfdev->base)) + drm_info(&pfdev->base, "Using Transparent Hugepage\n"); + else if (err) + drm_warn(&pfdev->base, "Can't use Transparent Hugepage (%d)\n", + err); +} + #ifdef CONFIG_DEBUG_FS static void panfrost_gem_debugfs_bo_add(struct panfrost_device *pfdev, struct panfrost_gem_object *bo) diff --git a/drivers/gpu/drm/panfrost/panfrost_gem.h b/drivers/gpu/drm/panf= rost/panfrost_gem.h index 8de3e76f2717..1a62529ff06f 100644 --- a/drivers/gpu/drm/panfrost/panfrost_gem.h +++ b/drivers/gpu/drm/panfrost/panfrost_gem.h @@ -124,6 +124,8 @@ drm_mm_node_to_panfrost_mapping(struct drm_mm_node *nod= e) return container_of(node, struct panfrost_gem_mapping, mmnode); } =20 +void panfrost_gem_init(struct panfrost_device *pfdev); + struct drm_gem_object *panfrost_gem_create_object(struct drm_device *dev, = size_t size); =20 struct drm_gem_object * --=20 2.47.3 From nobody Fri Dec 19 15:50:32 2025 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6530B33971D; Fri, 5 Dec 2025 09:12:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925961; cv=none; b=gebKvaVMaPhSQBKky07O5NCKGJjhQ+WBz/Zb3Q6qB9SwDyOuEJsoUPbxITS5+VlpzNoVumTMbDosValzvziQp20T+ERV4bgeztJe/9K9mUTpuz5VxxQFqmQ8xXzv1kC6d4jMtKlELlrQ9s2DgAU5gU9SKbsX/EFXiP/aTV88X4A= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764925961; c=relaxed/simple; bh=gYX/y+Q9NsyC9DrjRWsLnYa/A4w67M9CU3SA88eKex4=; 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(unknown [IPv6:2a01:e0a:5e3:6100:826d:bc07:e98c:84a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: loicmolinari) by bali.collaboradmins.com (Postfix) with ESMTPSA id 54B8C17E1428; Fri, 5 Dec 2025 10:12:31 +0100 (CET) From: =?UTF-8?q?Lo=C3=AFc=20Molinari?= To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Boris Brezillon , Rob Herring , Steven Price , Liviu Dudau , Melissa Wen , =?UTF-8?q?Ma=C3=ADra=20Canal?= , Hugh Dickins , Baolin Wang , Andrew Morton , =?UTF-8?q?Lo=C3=AFc=20Molinari?= , Al Viro , =?UTF-8?q?Miko=C5=82aj=20Wasiak?= , Christian Brauner , Nitin Gote , Andi Shyti , Jonathan Corbet , Christopher Healy , Matthew Wilcox , Bagas Sanjaya Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, kernel@collabora.com Subject: [PATCH v12 10/10] Documentation/gpu/drm-mm: Add THP paragraph to GEM mapping section Date: Fri, 5 Dec 2025 10:12:16 +0100 Message-ID: <20251205091216.150968-11-loic.molinari@collabora.com> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251205091216.150968-1-loic.molinari@collabora.com> References: <20251205091216.150968-1-loic.molinari@collabora.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Add a paragraph to the GEM Objects Creation section about the drm_gem_huge_mnt_create() helper and to the GEM objects mapping section explaining how transparent huge pages are handled by GEM. v4: - fix wording after huge_pages handler removal v6: - fix wording after map_pages handler removal v11: - mention drm_gem_huge_mnt_create() helper - add Boris and Ma=C3=ADra R-bs Signed-off-by: Lo=C3=AFc Molinari Reviewed-by: Bagas Sanjaya Reviewed-by: Boris Brezillon Reviewed-by: Ma=C3=ADra Canal --- Documentation/gpu/drm-mm.rst | 29 +++++++++++++++++++++++------ 1 file changed, 23 insertions(+), 6 deletions(-) diff --git a/Documentation/gpu/drm-mm.rst b/Documentation/gpu/drm-mm.rst index d55751cad67c..f22433470c76 100644 --- a/Documentation/gpu/drm-mm.rst +++ b/Documentation/gpu/drm-mm.rst @@ -155,7 +155,12 @@ drm_gem_object_init() will create an shmfs file of the requested size and store it into the struct :c:type:`struct drm_gem_object ` filp field. The memory is used as either main storage for the object when the graphics hardware -uses system memory directly or as a backing store otherwise. +uses system memory directly or as a backing store otherwise. Drivers +can call drm_gem_huge_mnt_create() to create, mount and use a huge +shmem mountpoint instead of the default one ('shm_mnt'). For builds +with CONFIG_TRANSPARENT_HUGEPAGE enabled, further calls to +drm_gem_object_init() will let shmem allocate huge pages when +possible. =20 Drivers are responsible for the actual physical pages allocation by calling shmem_read_mapping_page_gfp() for each page. @@ -290,15 +295,27 @@ The open and close operations must update the GEM obj= ect reference count. Drivers can use the drm_gem_vm_open() and drm_gem_vm_close() helper functions directly as open and close handlers. =20 -The fault operation handler is responsible for mapping individual pages -to userspace when a page fault occurs. Depending on the memory -allocation scheme, drivers can allocate pages at fault time, or can -decide to allocate memory for the GEM object at the time the object is -created. +The fault operation handler is responsible for mapping pages to +userspace when a page fault occurs. Depending on the memory allocation +scheme, drivers can allocate pages at fault time, or can decide to +allocate memory for the GEM object at the time the object is created. =20 Drivers that want to map the GEM object upfront instead of handling page faults can implement their own mmap file operation handler. =20 +In order to reduce page table overhead, if the internal shmem mountpoint +"shm_mnt" is configured to use transparent huge pages (for builds with +CONFIG_TRANSPARENT_HUGEPAGE enabled) and if the shmem backing store +managed to allocate a huge page for a faulty address, the fault handler +will first attempt to insert that huge page into the VMA before falling +back to individual page insertion. mmap() user address alignment for GEM +objects is handled by providing a custom get_unmapped_area file +operation which forwards to the shmem backing store. For most drivers, +which don't create a huge mountpoint by default or through a module +parameter, transparent huge pages can be enabled by either setting the +"transparent_hugepage_shmem" kernel parameter or the +"/sys/kernel/mm/transparent_hugepage/shmem_enabled" sysfs knob. + For platforms without MMU the GEM core provides a helper method drm_gem_dma_get_unmapped_area(). The mmap() routines will call this to get= a proposed address for the mapping. --=20 2.47.3