I remake the test case to be more simply.

And the send the new email.

Thanks,

--Hongzhi


On 9/4/19 10:36 AM, Hongzhi, Song wrote:
Anybody notice this?

--Hongzhi


On 7/17/19 4:34 PM, Hongzhi, Song wrote:
Hi friends,

*Description:*


    One LTP testcase, fs_fill.c, fails on btrfs with kernel error when unlink files on Btrfs device:

    "BTRFS warning (device loop0): could not allocate space for a delete; will truncate on mount".


    I found the loop block device formatted with btrfs roughly rangs from 460M to 560M will cause the error.

    256M and 1G all pass.


    The fs_fill.c source code:

[https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/fs/fs_fill/fs_fill.c]

    The fs_fill.c calls unlink which triggers the error.

[https://github.com/linux-test-project/ltp/blob/e3457e42c1b93f54bb81da746eba314fd34ad40e/testcases/kernel/fs/fs_fill/fs_fill.c#L55]

[https://github.com/linux-test-project/ltp/blob/e3457e42c1b93f54bb81da746eba314fd34ad40e/lib/safe_macros.c#L358]


*Error info:*

    The issue maybe not reproduced everytime but four fifths chance.

    fs_fill.c:53: INFO: Unlinking mntpoint/thread5/file0
    safe_macros.c:360: BROK: fs_fill.c:55: unlink(mntpoint/thread10/file0) failed: ENOSPC     safe_macros.c:360: BROK: fs_fill.c:55: unlink(mntpoint/thread11/file0) failed: ENOSPC     [62477.378848] BTRFS warning (device loop0): could not allocate space for a delete; will truncate on mount     [62477.378905] BTRFS warning (device loop0): could not allocate space for a delete; will truncate on mount



*Kernel:*

    After v5.2-rc1, qemux86-64

    # make -j40 ARCH=x86_64 CROSS_COMPILE=x86-64-gcc
    use qemu to bootup kernel


*LTP:*

    master branch: I tested on 20190625
    Reproduce:

    // build Ltp
    # cd Ltp-source
    # ./build.sh

    // copy files to qemu
    # cp runltp testcases/kernel/fs/fs_fill/fs_fill to qemu

    // login to qemu:
    // adjust block device size to 512M
    # vi runltp
    in function: create_block()
        dd if=/dev/zero of=${TMP}/test.img bs=1024 count=262144
        --->
        dd if=/dev/zero of=${TMP}/test.img bs=1024 count=524288

    // execute testcase
    # runltp -f fs -s fs_fill


*Analysis:*

    One new kernel commit contained in v5.2-rc1 introduces the issue.

    commit c8eaeac7b734347c3afba7008b7af62f37b9c140
    Author: Josef Bacik <jo...@toxicpanda.com>
    Date:   Wed Apr 10 15:56:10 2019 -0400

        btrfs: reserve delalloc metadata differently
        ...


Anyone's reply will be appreciated.

--Hongzhi







Reply via email to