[LU-7863] ZFS dmu_prefetch API change.

• Status: Resolved
• Project: Lustre
• Fix Version/s: Lustre 2.9.0
• Type: Task
• Priority: Major
• Reporter: John Malmberg (Inactive)
• Assignee: Nathaniel Clark
• Resolution: Fixed
• Labels: zfs

Environment

Centos 7.2, ZFS 0.6.5-158, lustre-2.58.50-3.10.0_327

Description

The API for the ZFS dmu_prefetch routine has changed. The new routine has both more parameters and the parameters in a different order.

Current work around is to append a hack to the ZFS include/sys/dmu.h used for building lustre.

      cat <<DELIM >> include/sys/dmu.h
#ifndef dmu_prefetch
#pragma GCC diagnostic push
#pragma GCC diagnostic warning "-Wunused-function"
#pragma GCC diagnostic ignored "-Wunused-function"
static inline void dmu_prefetch_old(objset_t *os, uint64_t object,
    uint64_t offset, uint64_t len) {
  dmu_prefetch(os, object, 0, offset, len, 0); }
#define dmu_prefetch dmu_prefetch_old
#pragma GCC diagnostic pop
#define dmu_prefetch dmu_prefetch_old
#endif
DELIM

Issue Links

• is duplicated by: LU-8423 error: too few arguments to function ...

Comments

[John Salinas (Inactive)]

This bug is blocking our ability to test zfs 0.6.5 with Lustre 2.8. We need zfs 0.6.5 as it has large blocks (over 1MB) which are needed for CORAL testing.

[Peter Jones]

Nathaniel

Are you able to give some pointers here? AFAIK it is possible to run 0.6.5 with 2.8 but that is just not the default because of LU-7404

Peter

[Nathaniel Clark]

According to Jinshan's comments on LU-7404 it's not the ZFS version, so I've opened LU-7870 to update to 0.6.5.5. I'll handle any API changes when I do that update, should have a patch in the next day.

[Nathaniel Clark]

Lustre master builds cleanly with 0.6.5.5, are you building against ZFS/SPL master and not the 0.6.5-release branch?

[John Malmberg (Inactive)]

Yes, we are building against ZFS/SPL master, not the release branch.

John Salinas just discussed this issue with Don Brady and we will be changing the builds to the 0.6.5.5 branch.

[Nathaniel Clark]

I'll work up a separate patch to deal with the change to dmu_prefetch() in zfs master.

[Gerrit Updater]

Nathaniel Clark ([e-mail]) uploaded a new patch: http://review.whamcloud.com/19293
Subject: LU-7863 osd-zfs: dmu_prefetch change in ZFS master
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: e17477bb4cf89d6551975556c0823695a199388d

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/19293/
Subject: LU-7863 osd-zfs: dmu_prefetch change in ZFS master
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 349c2be0e608c9afe85253192a4c1450306e9629

[Peter Jones]

Landed for 2.9