From: wuzhouhui <wuzhouhui14@mails.ucas.ac.cn>
To: linux-newbie@vger.kernel.org
Subject: Pointer compare in md driver
Date: Fri, 27 Oct 2017 16:08:25 +0800 [thread overview]
Message-ID: <aa2d080d-8410-ba9a-0e0b-084a08079dd8@mails.ucas.ac.cn> (raw)
Hi,
I have a question when reading md driver. Following is the code from
linux/drivers/md/md.c, function md_do_sync():
> for_each_mddev(mddev2, tmp) {
> if (mddev2 == mddev)
> continue;
> if (!mddev->parallel_resync
> && mddev2->curr_resync
> && match_mddev_units(mddev, mddev2)) {
> DEFINE_WAIT(wq);
> if (mddev < mddev2 && mddev->curr_resync == 2) {
> /* arbitrarily yield */
> mddev->curr_resync = 1;
> wake_up(&resync_wait);
> }
> if (mddev > mddev2 && mddev->curr_resync == 1)
> /* no need to wait here, we can wait the next
> * time 'round when curr_resync == 2
> */
> continue;
> /* We need to wait 'interruptible' so as not to
The type of mddev2 and mddev both are struct mddev *, so what's the
meaning of comparing these two variables?
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reply other threads:[~2017-10-27 8:08 UTC|newest]
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