From patchwork Sat Mar 22 21:26:08 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Osipenko X-Patchwork-Id: 14026428 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A3BCFC36008 for ; Sat, 22 Mar 2025 21:29:59 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F421010E22E; Sat, 22 Mar 2025 21:29:58 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=collabora.com header.i=dmitry.osipenko@collabora.com header.b="cKpXo8eB"; dkim-atps=neutral Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) by gabe.freedesktop.org (Postfix) with ESMTPS id 360FA10E18F for ; Sat, 22 Mar 2025 21:29:57 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; t=1742678986; cv=none; d=zohomail.com; s=zohoarc; b=WaJyEL9xZeU5zR4pgHILJlFQFZmUTtzc4hg6lx/PXbWT4I9jrv7pM40vpdVr+pZgLAeUb/nB62lQLYFm06BYCzmulIxWoEsITQ9BXeRLHrmjN62d9KhroTI6K5WGtANV8rjdxJLd3gSyarEUprS8jJvzOIXmIRtGjoT+sEyC0pU= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1742678986; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=jI2A6McB5nUab55GDN4/MJXKSOUMSiNkiu8ByBqPMPM=; b=eGtiThTAXaS4Rt47A4xIkV/+OVQYNyNC1cPlUQXjV5rsweVi4unRJrNTs4M6jHhTVawtNVJZyxHAVudC4kFFs4ENk29Imx6SqzfeY8byrhCY2yG1X34Y40jLqVl3C1w+tnMV1HvdUc+7oz1EWKC/ufjvo+iEm2IQeAWFhJVYMW8= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=dmitry.osipenko@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1742678986; s=zohomail; d=collabora.com; i=dmitry.osipenko@collabora.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:In-Reply-To:References:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=jI2A6McB5nUab55GDN4/MJXKSOUMSiNkiu8ByBqPMPM=; b=cKpXo8eBxoYzi7gEo4QhSot4SporbIAkd8H4e2AB5UtPtPnHLRFt11XciaDf12DI qdT0AZl9NSF1oM+KQutMmO/4V/DptjOAsYd9Nbk8r6SpucaDhT41BO7ylAIVRm8K7Li I7181BxmAsVXSBo/4VeWRjFbKunvKd2E/7znELSU= Received: by mx.zohomail.com with SMTPS id 1742678984353357.2761177607125; Sat, 22 Mar 2025 14:29:44 -0700 (PDT) From: Dmitry Osipenko To: David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , =?utf-8?q?Christian_K=C3=B6nig?= , Gerd Hoffmann , Qiang Yu , Steven Price , Boris Brezillon , Frank Binns , Matt Coster Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel@collabora.com Subject: [PATCH v20 10/10] drm/shmem-helper: Use refcount_t for vmap_use_count Date: Sun, 23 Mar 2025 00:26:08 +0300 Message-ID: <20250322212608.40511-11-dmitry.osipenko@collabora.com> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250322212608.40511-1-dmitry.osipenko@collabora.com> References: <20250322212608.40511-1-dmitry.osipenko@collabora.com> MIME-Version: 1.0 X-ZohoMailClient: External X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Use refcount_t helper for vmap_use_count to make refcounting consistent with pages_use_count and pages_pin_count that use refcount_t. This also makes vmapping to benefit from the refcount_t's overflow checks. Acked-by: Maxime Ripard Reviewed-by: Boris Brezillon Suggested-by: Boris Brezillon Signed-off-by: Dmitry Osipenko --- drivers/gpu/drm/drm_gem_shmem_helper.c | 28 ++++++++++------------ drivers/gpu/drm/tests/drm_gem_shmem_test.c | 6 ++--- include/drm/drm_gem_shmem_helper.h | 2 +- 3 files changed, 16 insertions(+), 20 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 84a196bbe44f..2d924d547a51 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -165,7 +165,7 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem) } else { dma_resv_lock(shmem->base.resv, NULL); - drm_WARN_ON(obj->dev, shmem->vmap_use_count); + drm_WARN_ON(obj->dev, refcount_read(&shmem->vmap_use_count)); if (shmem->sgt) { dma_unmap_sgtable(obj->dev->dev, shmem->sgt, @@ -355,23 +355,25 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, dma_resv_assert_held(shmem->base.resv); - if (shmem->vmap_use_count++ > 0) { + if (refcount_inc_not_zero(&shmem->vmap_use_count)) { iosys_map_set_vaddr(map, shmem->vaddr); return 0; } ret = drm_gem_shmem_pin_locked(shmem); if (ret) - goto err_zero_use; + return ret; if (shmem->map_wc) prot = pgprot_writecombine(prot); shmem->vaddr = vmap(shmem->pages, obj->size >> PAGE_SHIFT, VM_MAP, prot); - if (!shmem->vaddr) + if (!shmem->vaddr) { ret = -ENOMEM; - else + } else { iosys_map_set_vaddr(map, shmem->vaddr); + refcount_set(&shmem->vmap_use_count, 1); + } } if (ret) { @@ -384,8 +386,6 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, err_put_pages: if (!drm_gem_is_imported(obj)) drm_gem_shmem_unpin_locked(shmem); -err_zero_use: - shmem->vmap_use_count = 0; return ret; } @@ -413,14 +413,10 @@ void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem, } else { dma_resv_assert_held(shmem->base.resv); - if (drm_WARN_ON_ONCE(obj->dev, !shmem->vmap_use_count)) - return; - - if (--shmem->vmap_use_count > 0) - return; - - vunmap(shmem->vaddr); - drm_gem_shmem_unpin_locked(shmem); + if (refcount_dec_and_test(&shmem->vmap_use_count)) { + vunmap(shmem->vaddr); + drm_gem_shmem_unpin_locked(shmem); + } } shmem->vaddr = NULL; @@ -672,7 +668,7 @@ void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem, drm_printf_indent(p, indent, "pages_pin_count=%u\n", refcount_read(&shmem->pages_pin_count)); drm_printf_indent(p, indent, "pages_use_count=%u\n", refcount_read(&shmem->pages_use_count)); - drm_printf_indent(p, indent, "vmap_use_count=%u\n", shmem->vmap_use_count); + drm_printf_indent(p, indent, "vmap_use_count=%u\n", refcount_read(&shmem->vmap_use_count)); drm_printf_indent(p, indent, "vaddr=%p\n", shmem->vaddr); } EXPORT_SYMBOL_GPL(drm_gem_shmem_print_info); diff --git a/drivers/gpu/drm/tests/drm_gem_shmem_test.c b/drivers/gpu/drm/tests/drm_gem_shmem_test.c index 1459cdb0c413..81cadaecdd4f 100644 --- a/drivers/gpu/drm/tests/drm_gem_shmem_test.c +++ b/drivers/gpu/drm/tests/drm_gem_shmem_test.c @@ -168,7 +168,7 @@ static void drm_gem_shmem_test_vmap(struct kunit *test) shmem = drm_gem_shmem_create(drm_dev, TEST_SIZE); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, shmem); KUNIT_EXPECT_NULL(test, shmem->vaddr); - KUNIT_EXPECT_EQ(test, shmem->vmap_use_count, 0); + KUNIT_EXPECT_EQ(test, refcount_read(&shmem->vmap_use_count), 0); ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem); KUNIT_ASSERT_EQ(test, ret, 0); @@ -177,7 +177,7 @@ static void drm_gem_shmem_test_vmap(struct kunit *test) KUNIT_ASSERT_EQ(test, ret, 0); KUNIT_ASSERT_NOT_NULL(test, shmem->vaddr); KUNIT_ASSERT_FALSE(test, iosys_map_is_null(&map)); - KUNIT_EXPECT_EQ(test, shmem->vmap_use_count, 1); + KUNIT_EXPECT_EQ(test, refcount_read(&shmem->vmap_use_count), 1); iosys_map_memset(&map, 0, TEST_BYTE, TEST_SIZE); for (i = 0; i < TEST_SIZE; i++) @@ -185,7 +185,7 @@ static void drm_gem_shmem_test_vmap(struct kunit *test) drm_gem_shmem_vunmap_locked(shmem, &map); KUNIT_EXPECT_NULL(test, shmem->vaddr); - KUNIT_EXPECT_EQ(test, shmem->vmap_use_count, 0); + KUNIT_EXPECT_EQ(test, refcount_read(&shmem->vmap_use_count), 0); } /* diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index 8b9bba87ae63..b4f993da3cae 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -82,7 +82,7 @@ struct drm_gem_shmem_object { * Reference count on the virtual address. * The address are un-mapped when the count reaches zero. */ - unsigned int vmap_use_count; + refcount_t vmap_use_count; /** * @pages_mark_dirty_on_put: