>>>>> "Tomasz" == Tomasz Majchrzak <tomasz.majchrzak@xxxxxxxxx> writes:
Tomasz> A 'faulty' drive is being removed from a container after it
Tomasz> has been released by an array, however there is a race
Tomasz> there. The drive is released asynchronously by a monitor but
Tomasz> sometimes it doesn't happen before container checks it. It
Tomasz> results in a container refusing to remove a drive as it still
Tomasz> seems to be a part of some array.
Tomasz> It seems 'ping_monitor' could be a solution here to assure
Tomasz> monitor has had a chance to process the events, however it
Tomasz> doesn't resolve the problem - sometimes an array has to
Tomasz> request a release of the drive few times (as the array is
Tomasz> busy) and single 'ping_monitor' call is not sufficient. As
Tomasz> there is no way to query monitor progress, it forces us to
Tomasz> retry a check several times before an error is returned.
Tomasz> Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@xxxxxxxxx>
Tomasz> ---
Tomasz> Manage.c | 38 +++++++++++++++++++++++++-------------
Tomasz> 1 file changed, 25 insertions(+), 13 deletions(-)
Tomasz> diff --git a/Manage.c b/Manage.c
Tomasz> index e2e88b8..7f8eb88 100644
Tomasz> --- a/Manage.c
Tomasz> +++ b/Manage.c
Tomasz> @@ -1125,19 +1125,31 @@ int Manage_remove(struct supertype *tst, int fd, struct mddev_dev *dv,
Tomasz> */
Tomasz> if (rdev == 0)
Tomasz> ret = -1;
Tomasz> - else
Tomasz> - ret = sysfs_unique_holder(devnm, rdev);
Tomasz> - if (ret == 0) {
Tomasz> - pr_err("%s is not a member, cannot remove.\n",
Tomasz> - dv->devname);
Tomasz> - close(lfd);
Tomasz> - return -1;
Tomasz> - }
Tomasz> - if (ret >= 2) {
Tomasz> - pr_err("%s is still in use, cannot remove.\n",
Tomasz> - dv->devname);
Tomasz> - close(lfd);
Tomasz> - return -1;
Tomasz> + else {
Tomasz> + /* The drive has already been set to 'faulty', however monitor might
Tomasz> + * not have had time to process it and the drive might still have
Tomasz> + * an entry in the 'holders' directory. Try a few times to avoid
Tomasz> + * a false error */
Tomasz> + int count = 20;
Tomasz> + do {
Tomasz> + ret = sysfs_unique_holder(devnm, rdev);
Tomasz> + if (ret < 2)
Tomasz> + break;
Tomasz> + usleep(100000);
Really, you're sleeping 10 seconds without telling the user? That
seems to be a bit obnoxious. Logging something here would be good.
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