[-next,v3,4/7] md: factor out a helper rdev_removeable() from remove_and_add_spares()
Commit Message
From: Yu Kuai <yukuai3@huawei.com>
There are no functional changes, just to make the code simpler and
prepare to delay remove_and_add_spares() to md_start_sync().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
---
drivers/md/md.c | 33 +++++++++++++++++++--------------
1 file changed, 19 insertions(+), 14 deletions(-)
Comments
Hi,
在 2023/08/22 18:19, Xiao Ni 写道:
> On Sun, Aug 20, 2023 at 5:13 PM Yu Kuai <yukuai1@huaweicloud.com> wrote:
>>
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> There are no functional changes, just to make the code simpler and
>> prepare to delay remove_and_add_spares() to md_start_sync().
>>
>> Signed-off-by: Yu Kuai <yukuai3@huawei.com>
>> ---
>> drivers/md/md.c | 33 +++++++++++++++++++--------------
>> 1 file changed, 19 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/md/md.c b/drivers/md/md.c
>> index 561cac13ff96..ceace5ffadd6 100644
>> --- a/drivers/md/md.c
>> +++ b/drivers/md/md.c
>> @@ -9153,6 +9153,22 @@ void md_do_sync(struct md_thread *thread)
>> }
>> EXPORT_SYMBOL_GPL(md_do_sync);
>>
>> +static bool rdev_removeable(struct md_rdev *rdev)
>> +{
>> + if (rdev->raid_disk < 0 || test_bit(Blocked, &rdev->flags) ||
>> + atomic_read(&rdev->nr_pending))
>> + return false;
>> +
>> + if (test_bit(RemoveSynchronized, &rdev->flags))
>> + return true;
>> +
>> + if (test_bit(In_sync, &rdev->flags) ||
>> + test_bit(Journal, &rdev->flags))
>> + return false;
>> +
>> + return true;
>> +}
>> +
>> static int remove_and_add_spares(struct mddev *mddev,
>> struct md_rdev *this)
>> {
>> @@ -9166,11 +9182,7 @@ static int remove_and_add_spares(struct mddev *mddev,
>> return 0;
>>
>> rdev_for_each(rdev, mddev) {
>> - if ((this == NULL || rdev == this) &&
>> - rdev->raid_disk >= 0 &&
>> - !test_bit(Blocked, &rdev->flags) &&
>> - test_bit(Faulty, &rdev->flags) &&
>> - atomic_read(&rdev->nr_pending)==0) {
>> + if ((this == NULL || rdev == this) && rdev_removeable(rdev)) {
>
> There is a small change with the original method. Before this patch,
> it checks the Faulty flag when setting RemoveSynchronized and it
> checks RemoveSynchronized and "!In_sync && !Journal". I'm not sure if
> it's right or not.
Yes, there is a small change. After a second thought, I think it's OK
to leave the code to set RemoveSynchronized where it is for now, because
it'll be removed later. I don't need to bother factor out a common code
to set RemoveSynchronized and call hot_remove_disk().
By the way, once refactor of mddev_suspend() is done, then access to
rdev from fastpath will be replaced from:
rcu_read_lock()
...
rcu_read_unlock()
to:
md_array_enter()
// grab 'active_io', 'active_io' will probably be renamed
...
md_array_exit()
That's why I said RemoveSynchronized will be removed.
Thanks,
Kuai
>
>> /* Faulty non-Blocked devices with nr_pending == 0
>> * never get nr_pending incremented,
>> * never get Faulty cleared, and never get Blocked set.
>> @@ -9185,19 +9197,12 @@ static int remove_and_add_spares(struct mddev *mddev,
>> synchronize_rcu();
>> rdev_for_each(rdev, mddev) {
>> if ((this == NULL || rdev == this) &&
>> - rdev->raid_disk >= 0 &&
>> - !test_bit(Blocked, &rdev->flags) &&
>> - ((test_bit(RemoveSynchronized, &rdev->flags) ||
>> - (!test_bit(In_sync, &rdev->flags) &&
>> - !test_bit(Journal, &rdev->flags))) &&
>> - atomic_read(&rdev->nr_pending)==0)) {
>> - if (mddev->pers->hot_remove_disk(
>> - mddev, rdev) == 0) {
>> + rdev_removeable(rdev) &&
>> + mddev->pers->hot_remove_disk(mddev, rdev) == 0) {
>> sysfs_unlink_rdev(mddev, rdev);
>> rdev->saved_raid_disk = rdev->raid_disk;
>> rdev->raid_disk = -1;
>> removed++;
>> - }
>> }
>> if (remove_some && test_bit(RemoveSynchronized, &rdev->flags))
>> clear_bit(RemoveSynchronized, &rdev->flags);
>> --
>> 2.39.2
>>
>
> .
>
@@ -9153,6 +9153,22 @@ void md_do_sync(struct md_thread *thread)
}
EXPORT_SYMBOL_GPL(md_do_sync);
+static bool rdev_removeable(struct md_rdev *rdev)
+{
+ if (rdev->raid_disk < 0 || test_bit(Blocked, &rdev->flags) ||
+ atomic_read(&rdev->nr_pending))
+ return false;
+
+ if (test_bit(RemoveSynchronized, &rdev->flags))
+ return true;
+
+ if (test_bit(In_sync, &rdev->flags) ||
+ test_bit(Journal, &rdev->flags))
+ return false;
+
+ return true;
+}
+
static int remove_and_add_spares(struct mddev *mddev,
struct md_rdev *this)
{
@@ -9166,11 +9182,7 @@ static int remove_and_add_spares(struct mddev *mddev,
return 0;
rdev_for_each(rdev, mddev) {
- if ((this == NULL || rdev == this) &&
- rdev->raid_disk >= 0 &&
- !test_bit(Blocked, &rdev->flags) &&
- test_bit(Faulty, &rdev->flags) &&
- atomic_read(&rdev->nr_pending)==0) {
+ if ((this == NULL || rdev == this) && rdev_removeable(rdev)) {
/* Faulty non-Blocked devices with nr_pending == 0
* never get nr_pending incremented,
* never get Faulty cleared, and never get Blocked set.
@@ -9185,19 +9197,12 @@ static int remove_and_add_spares(struct mddev *mddev,
synchronize_rcu();
rdev_for_each(rdev, mddev) {
if ((this == NULL || rdev == this) &&
- rdev->raid_disk >= 0 &&
- !test_bit(Blocked, &rdev->flags) &&
- ((test_bit(RemoveSynchronized, &rdev->flags) ||
- (!test_bit(In_sync, &rdev->flags) &&
- !test_bit(Journal, &rdev->flags))) &&
- atomic_read(&rdev->nr_pending)==0)) {
- if (mddev->pers->hot_remove_disk(
- mddev, rdev) == 0) {
+ rdev_removeable(rdev) &&
+ mddev->pers->hot_remove_disk(mddev, rdev) == 0) {
sysfs_unlink_rdev(mddev, rdev);
rdev->saved_raid_disk = rdev->raid_disk;
rdev->raid_disk = -1;
removed++;
- }
}
if (remove_some && test_bit(RemoveSynchronized, &rdev->flags))
clear_bit(RemoveSynchronized, &rdev->flags);