From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E004C433FE for ; Thu, 14 Oct 2021 20:05:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 565146105A for ; Thu, 14 Oct 2021 20:05:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234077AbhJNUHz (ORCPT ); Thu, 14 Oct 2021 16:07:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232635AbhJNUHx (ORCPT ); Thu, 14 Oct 2021 16:07:53 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AE46CC061570 for ; Thu, 14 Oct 2021 13:05:48 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 124-20020a251182000000b005a027223ed9so8318640ybr.13 for ; Thu, 14 Oct 2021 13:05:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:cc; bh=ZRPB/4UTEnoxBnzZ+VTaoJIQynoSb9eRpmHQI9uJw0c=; b=JBXrcusse+VlSdrRREA5cHIAAjdmK1jd/X1u8JinsjqzFLt1bp5nVoka4BeJDqycVO 85lV2yZ7QbmCIc3vI1qAJZYbA941GxPQW6rSANFNC9I7QfzOz6+65YO4L/1zSShzTWJ5 Ga3HGC0nwnpKvTurxRgVumSOGo5L0XscbwuQFOHqcmVeqQ/9s3gr2RUcjWQrfaBkRlLt TT9AytzJFHiTqhMh6r0pqYSmkzJLiJKu44Enx71GacoZswYSz2SxVNavyfirFjDAayWs 51xka5eFo8ZudhX5fB16zO3dgb0ySFRyWH82ezf2cP6BVFy+2AmP4oyfAqbtCxByTced b7fA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:cc; bh=ZRPB/4UTEnoxBnzZ+VTaoJIQynoSb9eRpmHQI9uJw0c=; b=kMcSIhUOnbbkTh4bzWU/1gzl5BIBMrp/bw/4b5RuVWBuy0qoDqu5h1QLOjWA0+qZKX O2g4VP44rSK26Hwc28TKClpgwyZQ4qug2fSDfbNzGIknZbEuVhdvx/Ici88Uk+ws/5L/ o9JkhS3wJlhKYDO4FI7u/73QLRxng3TqR1moJJKO+pu/BkqGDeT1pI0JuhVHXaFtLdtv jyKCrmJ/rPFVnnODwesUIuJFNQ11EuF9fwxPGX4WY+WWQI07mzORT56049XC2S+zvCPx TOdu2MNSyF/EqXGei/3T6tTHLzD+oW48eDfVS89RjbJh2pC+1bL+JnsVQ7NfF/n0vpyp HHgQ== X-Gm-Message-State: AOAM531JRxXxOjssdJEyP4Hrm2JviY6xuto2jO5oyRSJadqf3IH6Ofr4 0D/BPDkpQoHGM4L5fOdYOnLRd9RU3DUKMxY/AA== X-Google-Smtp-Source: ABdhPJxXfBotalDBo3TIoIhP12Kti0OtvnMropJgb1c3OjC5s0+g0NRYI5rr5aFycROowoHQQYGrWBUeEu1pY+wrNA== X-Received: from almasrymina.svl.corp.google.com ([2620:15c:2cd:202:38a9:b808:3666:4b7b]) (user=almasrymina job=sendgmr) by 2002:a25:5ec5:: with SMTP id s188mr8653038ybb.417.1634241947956; Thu, 14 Oct 2021 13:05:47 -0700 (PDT) Date: Thu, 14 Oct 2021 13:05:42 -0700 In-Reply-To: <20211014200542.4126947-1-almasrymina@google.com> Message-Id: <20211014200542.4126947-2-almasrymina@google.com> Mime-Version: 1.0 References: <20211014200542.4126947-1-almasrymina@google.com> X-Mailer: git-send-email 2.33.0.1079.g6e70778dc9-goog Subject: [PATCH v8 2/2] mm, hugepages: Add hugetlb vma mremap() test From: Mina Almasry Cc: Mina Almasry , Mike Kravetz , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ken Chen , Chris Kennelly , Michal Hocko , Vlastimil Babka , Kirill Shutemov Content-Type: text/plain; charset="UTF-8" To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Signed-off-by: Mina Almasry Acked-by: Mike Kravetz Cc: Mike Kravetz Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Cc: Ken Chen Cc: Chris Kennelly Cc: Michal Hocko Cc: Vlastimil Babka Cc: Kirill Shutemov --- Changes in v8: - Integrated hugepage-mremap into run_vmtests.sh - Added Ack from Mike Kravetz Changes in v6: - Reverted change in v4: test case now passes huge page aligned addrs to mmap/mremap. Changes in v4: - Added comments to make test output clearer. - Modified test case slightly to test hugepage alignment of new_addr. --- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 1 + tools/testing/selftests/vm/hugepage-mremap.c | 161 +++++++++++++++++++ tools/testing/selftests/vm/run_vmtests.sh | 11 ++ 4 files changed, 174 insertions(+) create mode 100644 tools/testing/selftests/vm/hugepage-mremap.c diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index b02eac613fdda..2e7e86e852828 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only hugepage-mmap +hugepage-mremap hugepage-shm khugepaged map_hugetlb diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index d9605bd10f2de..1607322a112c9 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -29,6 +29,7 @@ TEST_GEN_FILES = compaction_test TEST_GEN_FILES += gup_test TEST_GEN_FILES += hmm-tests TEST_GEN_FILES += hugepage-mmap +TEST_GEN_FILES += hugepage-mremap TEST_GEN_FILES += hugepage-shm TEST_GEN_FILES += khugepaged TEST_GEN_FILES += madv_populate diff --git a/tools/testing/selftests/vm/hugepage-mremap.c b/tools/testing/selftests/vm/hugepage-mremap.c new file mode 100644 index 0000000000000..76d5f42bf4ae2 --- /dev/null +++ b/tools/testing/selftests/vm/hugepage-mremap.c @@ -0,0 +1,161 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * hugepage-mremap: + * + * Example of remapping huge page memory in a user application using the + * mremap system call. Code assumes a hugetlbfs filesystem is mounted + * at './huge'. The code will use 10MB worth of huge pages. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include /* Definition of O_* constants */ +#include /* Definition of SYS_* constants */ +#include +#include +#include + +#define LENGTH (1UL * 1024 * 1024 * 1024) + +#define PROTECTION (PROT_READ | PROT_WRITE | PROT_EXEC) +#define FLAGS (MAP_SHARED | MAP_ANONYMOUS) + +static void check_bytes(char *addr) +{ + printf("First hex is %x\n", *((unsigned int *)addr)); +} + +static void write_bytes(char *addr) +{ + unsigned long i; + + for (i = 0; i < LENGTH; i++) + *(addr + i) = (char)i; +} + +static int read_bytes(char *addr) +{ + unsigned long i; + + check_bytes(addr); + for (i = 0; i < LENGTH; i++) + if (*(addr + i) != (char)i) { + printf("Mismatch at %lu\n", i); + return 1; + } + return 0; +} + +static void register_region_with_uffd(char *addr, size_t len) +{ + long uffd; /* userfaultfd file descriptor */ + struct uffdio_api uffdio_api; + struct uffdio_register uffdio_register; + + /* Create and enable userfaultfd object. */ + + uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + if (uffd == -1) { + perror("userfaultfd"); + exit(1); + } + + uffdio_api.api = UFFD_API; + uffdio_api.features = 0; + if (ioctl(uffd, UFFDIO_API, &uffdio_api) == -1) { + perror("ioctl-UFFDIO_API"); + exit(1); + } + + /* Create a private anonymous mapping. The memory will be + * demand-zero paged--that is, not yet allocated. When we + * actually touch the memory, it will be allocated via + * the userfaultfd. + */ + + addr = mmap(NULL, len, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + printf("Address returned by mmap() = %p\n", addr); + + /* Register the memory range of the mapping we just created for + * handling by the userfaultfd object. In mode, we request to track + * missing pages (i.e., pages that have not yet been faulted in). + */ + + uffdio_register.range.start = (unsigned long)addr; + uffdio_register.range.len = len; + uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING; + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1) { + perror("ioctl-UFFDIO_REGISTER"); + exit(1); + } +} + +int main(void) +{ + int ret = 0; + + int fd = open("/huge/test", O_CREAT | O_RDWR, 0755); + + if (fd < 0) { + perror("Open failed"); + exit(1); + } + + /* mmap to a PUD aligned address to hopefully trigger pmd sharing. */ + unsigned long suggested_addr = 0x7eaa40000000; + void *haddr = mmap((void *)suggested_addr, LENGTH, PROTECTION, + MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0); + printf("Map haddr: Returned address is %p\n", haddr); + if (haddr == MAP_FAILED) { + perror("mmap1"); + exit(1); + } + + /* mmap again to a dummy address to hopefully trigger pmd sharing. */ + suggested_addr = 0x7daa40000000; + void *daddr = mmap((void *)suggested_addr, LENGTH, PROTECTION, + MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0); + printf("Map daddr: Returned address is %p\n", daddr); + if (daddr == MAP_FAILED) { + perror("mmap3"); + exit(1); + } + + suggested_addr = 0x7faa40000000; + void *vaddr = + mmap((void *)suggested_addr, LENGTH, PROTECTION, FLAGS, -1, 0); + printf("Map vaddr: Returned address is %p\n", vaddr); + if (vaddr == MAP_FAILED) { + perror("mmap2"); + exit(1); + } + + register_region_with_uffd(haddr, LENGTH); + + void *addr = mremap(haddr, LENGTH, LENGTH, + MREMAP_MAYMOVE | MREMAP_FIXED, vaddr); + if (addr == MAP_FAILED) { + perror("mremap"); + exit(1); + } + + printf("Mremap: Returned address is %p\n", addr); + check_bytes(addr); + write_bytes(addr); + ret = read_bytes(addr); + + munmap(addr, LENGTH); + + return ret; +} diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index 45e803af7c775..a24d30af30949 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -108,6 +108,17 @@ else echo "[PASS]" fi +echo "-----------------------" +echo "running hugepage-mremap" +echo "-----------------------" +./hugepage-mremap +if [ $? -ne 0 ]; then + echo "[FAIL]" + exitcode=1 +else + echo "[PASS]" +fi + echo "NOTE: The above hugetlb tests provide minimal coverage. Use" echo " https://github.com/libhugetlbfs/libhugetlbfs.git for" echo " hugetlb regression testing." -- 2.33.0.1079.g6e70778dc9-goog From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F165C433EF for ; Thu, 14 Oct 2021 20:05:50 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CED186105A for ; Thu, 14 Oct 2021 20:05:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org CED186105A Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 617B6900002; Thu, 14 Oct 2021 16:05:49 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5A0E4940008; 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Thu, 14 Oct 2021 13:05:47 -0700 (PDT) Date: Thu, 14 Oct 2021 13:05:42 -0700 In-Reply-To: <20211014200542.4126947-1-almasrymina@google.com> Message-Id: <20211014200542.4126947-2-almasrymina@google.com> Mime-Version: 1.0 References: <20211014200542.4126947-1-almasrymina@google.com> X-Mailer: git-send-email 2.33.0.1079.g6e70778dc9-goog Subject: [PATCH v8 2/2] mm, hugepages: Add hugetlb vma mremap() test From: Mina Almasry Cc: Mina Almasry , Mike Kravetz , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ken Chen , Chris Kennelly , Michal Hocko , Vlastimil Babka , Kirill Shutemov Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: sh4a9cfa9gfhhdbxzms3kdkwwn1j47yg Authentication-Results: imf12.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b=JBXrcuss; spf=pass (imf12.hostedemail.com: domain of 3m41oYQsKCGoITUIaZgUQVIOWWOTM.KWUTQVcf-UUSdIKS.WZO@flex--almasrymina.bounces.google.com designates 209.85.219.202 as permitted sender) smtp.mailfrom=3m41oYQsKCGoITUIaZgUQVIOWWOTM.KWUTQVcf-UUSdIKS.WZO@flex--almasrymina.bounces.google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 9891F10000A0 X-HE-Tag: 1634241948-766188 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Signed-off-by: Mina Almasry Acked-by: Mike Kravetz Cc: Mike Kravetz Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Cc: Ken Chen Cc: Chris Kennelly Cc: Michal Hocko Cc: Vlastimil Babka Cc: Kirill Shutemov --- Changes in v8: - Integrated hugepage-mremap into run_vmtests.sh - Added Ack from Mike Kravetz Changes in v6: - Reverted change in v4: test case now passes huge page aligned addrs to mmap/mremap. Changes in v4: - Added comments to make test output clearer. - Modified test case slightly to test hugepage alignment of new_addr. --- tools/testing/selftests/vm/.gitignore | 1 + tools/testing/selftests/vm/Makefile | 1 + tools/testing/selftests/vm/hugepage-mremap.c | 161 +++++++++++++++++++ tools/testing/selftests/vm/run_vmtests.sh | 11 ++ 4 files changed, 174 insertions(+) create mode 100644 tools/testing/selftests/vm/hugepage-mremap.c diff --git a/tools/testing/selftests/vm/.gitignore b/tools/testing/selftests/vm/.gitignore index b02eac613fdda..2e7e86e852828 100644 --- a/tools/testing/selftests/vm/.gitignore +++ b/tools/testing/selftests/vm/.gitignore @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only hugepage-mmap +hugepage-mremap hugepage-shm khugepaged map_hugetlb diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index d9605bd10f2de..1607322a112c9 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -29,6 +29,7 @@ TEST_GEN_FILES = compaction_test TEST_GEN_FILES += gup_test TEST_GEN_FILES += hmm-tests TEST_GEN_FILES += hugepage-mmap +TEST_GEN_FILES += hugepage-mremap TEST_GEN_FILES += hugepage-shm TEST_GEN_FILES += khugepaged TEST_GEN_FILES += madv_populate diff --git a/tools/testing/selftests/vm/hugepage-mremap.c b/tools/testing/selftests/vm/hugepage-mremap.c new file mode 100644 index 0000000000000..76d5f42bf4ae2 --- /dev/null +++ b/tools/testing/selftests/vm/hugepage-mremap.c @@ -0,0 +1,161 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * hugepage-mremap: + * + * Example of remapping huge page memory in a user application using the + * mremap system call. Code assumes a hugetlbfs filesystem is mounted + * at './huge'. The code will use 10MB worth of huge pages. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include /* Definition of O_* constants */ +#include /* Definition of SYS_* constants */ +#include +#include +#include + +#define LENGTH (1UL * 1024 * 1024 * 1024) + +#define PROTECTION (PROT_READ | PROT_WRITE | PROT_EXEC) +#define FLAGS (MAP_SHARED | MAP_ANONYMOUS) + +static void check_bytes(char *addr) +{ + printf("First hex is %x\n", *((unsigned int *)addr)); +} + +static void write_bytes(char *addr) +{ + unsigned long i; + + for (i = 0; i < LENGTH; i++) + *(addr + i) = (char)i; +} + +static int read_bytes(char *addr) +{ + unsigned long i; + + check_bytes(addr); + for (i = 0; i < LENGTH; i++) + if (*(addr + i) != (char)i) { + printf("Mismatch at %lu\n", i); + return 1; + } + return 0; +} + +static void register_region_with_uffd(char *addr, size_t len) +{ + long uffd; /* userfaultfd file descriptor */ + struct uffdio_api uffdio_api; + struct uffdio_register uffdio_register; + + /* Create and enable userfaultfd object. */ + + uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); + if (uffd == -1) { + perror("userfaultfd"); + exit(1); + } + + uffdio_api.api = UFFD_API; + uffdio_api.features = 0; + if (ioctl(uffd, UFFDIO_API, &uffdio_api) == -1) { + perror("ioctl-UFFDIO_API"); + exit(1); + } + + /* Create a private anonymous mapping. The memory will be + * demand-zero paged--that is, not yet allocated. When we + * actually touch the memory, it will be allocated via + * the userfaultfd. + */ + + addr = mmap(NULL, len, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (addr == MAP_FAILED) { + perror("mmap"); + exit(1); + } + + printf("Address returned by mmap() = %p\n", addr); + + /* Register the memory range of the mapping we just created for + * handling by the userfaultfd object. In mode, we request to track + * missing pages (i.e., pages that have not yet been faulted in). + */ + + uffdio_register.range.start = (unsigned long)addr; + uffdio_register.range.len = len; + uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING; + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1) { + perror("ioctl-UFFDIO_REGISTER"); + exit(1); + } +} + +int main(void) +{ + int ret = 0; + + int fd = open("/huge/test", O_CREAT | O_RDWR, 0755); + + if (fd < 0) { + perror("Open failed"); + exit(1); + } + + /* mmap to a PUD aligned address to hopefully trigger pmd sharing. */ + unsigned long suggested_addr = 0x7eaa40000000; + void *haddr = mmap((void *)suggested_addr, LENGTH, PROTECTION, + MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0); + printf("Map haddr: Returned address is %p\n", haddr); + if (haddr == MAP_FAILED) { + perror("mmap1"); + exit(1); + } + + /* mmap again to a dummy address to hopefully trigger pmd sharing. */ + suggested_addr = 0x7daa40000000; + void *daddr = mmap((void *)suggested_addr, LENGTH, PROTECTION, + MAP_HUGETLB | MAP_SHARED | MAP_POPULATE, fd, 0); + printf("Map daddr: Returned address is %p\n", daddr); + if (daddr == MAP_FAILED) { + perror("mmap3"); + exit(1); + } + + suggested_addr = 0x7faa40000000; + void *vaddr = + mmap((void *)suggested_addr, LENGTH, PROTECTION, FLAGS, -1, 0); + printf("Map vaddr: Returned address is %p\n", vaddr); + if (vaddr == MAP_FAILED) { + perror("mmap2"); + exit(1); + } + + register_region_with_uffd(haddr, LENGTH); + + void *addr = mremap(haddr, LENGTH, LENGTH, + MREMAP_MAYMOVE | MREMAP_FIXED, vaddr); + if (addr == MAP_FAILED) { + perror("mremap"); + exit(1); + } + + printf("Mremap: Returned address is %p\n", addr); + check_bytes(addr); + write_bytes(addr); + ret = read_bytes(addr); + + munmap(addr, LENGTH); + + return ret; +} diff --git a/tools/testing/selftests/vm/run_vmtests.sh b/tools/testing/selftests/vm/run_vmtests.sh index 45e803af7c775..a24d30af30949 100755 --- a/tools/testing/selftests/vm/run_vmtests.sh +++ b/tools/testing/selftests/vm/run_vmtests.sh @@ -108,6 +108,17 @@ else echo "[PASS]" fi +echo "-----------------------" +echo "running hugepage-mremap" +echo "-----------------------" +./hugepage-mremap +if [ $? -ne 0 ]; then + echo "[FAIL]" + exitcode=1 +else + echo "[PASS]" +fi + echo "NOTE: The above hugetlb tests provide minimal coverage. Use" echo " https://github.com/libhugetlbfs/libhugetlbfs.git for" echo " hugetlb regression testing." -- 2.33.0.1079.g6e70778dc9-goog