[LU-3963] cleanup libcfs wrappers

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.7.0
• Affects Version/s: Lustre 2.4.0, Lustre 2.5.0
• Labels: emc patch

Epic

client

• Assignee: Nathaniel Clark
• Reporter: Peng Tao

Description

Migrate libcfs to emulate Linux kernel APIs, so that when submitting Linux client to upstream kernel, we don't need the abstraction layer which will be rejected by kernel maintainers. The majority of libcfs are cfs_* or ll_* wrappers, and can be cleaned up with scripts doing like "s/cfs_spin_lock/spin_lock". For other functions that cannot be cleaned up this way, we need to look at them in a case-by-case basis.

Issue Links

• duplicates: LU-1346 cleanup libcfs
• is related to: LU-5018 e2fsprogs build failed
• is related to: LU-2245 failure on sanity.sh test_101c: Small 4k read IO 1!
• is related to: LU-5411 cfs_hlist_for_each_entry() not working as intended
• is related to: LU-8354 soft lockup in ldlm_plain_compat_queue

Comments

[James A Simmons]

Phase I of this work is complete. No more cfs_list or cfs_atomic etc. Now we are unto phase II which is putting libcfs on a diet. Lots of wrappers still exist that are no longer needed so we will now start that cleanup. First patch for that cleanup is here:

http://review.whamcloud.com/#/c/11963

[James A Simmons]

Last two patches posted have been merged. One last patch for cfs list wrrappers is here:

http://review.whamcloud.com/#/c/11797

[James A Simmons]

http://review.whamcloud.com/#/c/11725 - Empty file removal

http://review.whamcloud.com/#/c/11729 - Removal last of cfs wrappers for SMP handling.

[Jian Yu]

The patches for replacing direct HZ access with Linux kernel APIs will be tracked in LU-5443.

[James A Simmons]

http://review.whamcloud.com/#/c/10387
http://review.whamcloud.com/#/c/10525
http://review.whamcloud.com/#/c/10526

[Nathaniel Clark]

http://review.whamcloud.com/10247

[James A Simmons]

List cleanup patches:

http://review.whamcloud.com/#/c/9369
http://review.whamcloud.com/#/c/9904
http://review.whamcloud.com/#/c/9944

[Nathaniel Clark]

James, Sorry about that.

[James A Simmons]

Patch 7073 is still outstanding. Also we have the cfs_list to convert. Please reopen this ticket.

[Nathaniel Clark]

Merged to head

[James A Simmons]

Both patches 7072 and 7074 are merged. The patches left to support linux atomics are:

http://review.whamcloud.com/#/c/7073
http://review.whamcloud.com/#/c/7077