[LU-5988] obd_memory stats cleanup

• Type: Task
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.8.0
• Labels: easy
• Assignee: Andreas Dilger
• Reporter: Andreas Dilger

Description

The obd_memory statistics have atrophied over time and could use a cleanup.

• OBD_MEMORY_PAGES_STAT is no longer really used. It was previously used via OBD_ALLOC_PAGE-> __OBD_PAGE_ALLOC_VERBOSE-> obd_pages_add() but that macro is not used in llite or obdfilter/OSD anymore. This whole series of macros (including OBD_PAGE_FREE(), obd_pages_sub()) could be removed (with a fond memory that it was useful to know how many data pages Lustre had allocated, at the time it was working).
• OBD_MEMORY_STAT is only ever used to get the total amount of memory, so it doesn't make sense to keep this as a lprocfs_counter, it could just be a percpu_counter. That means obd_memory could also be removed.
• lprocfs_counter and lprocfs_percpu might potentially benefit from using the upstream kernel percpu_counter infrastructure instead of rolling our own alloc/free/counting.

Comments

[Peter Jones]

Landed for 2.8

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/15110/
Subject: LU-5988 obdclass: drop malloc fault and page accounting
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 33754bef1a26b40687f2bb8677fb3aadcc2d5c23

[Andreas Dilger]

Partial patch here http://review.whamcloud.com/15110