[LU-5396] annotations for sparse static analyzer

• Type: Bug
• Resolution: Fixed
• Priority: Trivial
• Fix Version/s: Lustre 2.7.0
• Affects Version/s: Lustre 2.6.0
• Labels: patch
• Severity: 3
• Assignee: Dmitry Eremin (Inactive)
• Reporter: Frank Zago (Inactive)

Description

sparse (git://git.kernel.org/pub/scm/devel/sparse/sparse.git) is a static analyzer used in kernel dev. After installing it, it can easily be used with Lustre:

make C=1

Currently there is about 3900 warnings. Most of it is noise, and a few annotations will silence them. However in that noise, some bugs might be lurking.

Besides finding bugs, it currently tags 1000 functions that can be made static. Once marked static, that will enable the compiler to optimize them more aggressively, which may lead to some minor performance improvements.

So far I've cleared about 1000 of them and found only one bug (strcmp with userspace provided buffer in fld_proc_hash_seq_write) and several unused functions.

Issue Links

• is related to: LU-2753 Tracking bug for static code analysis fixes.
• is related to: LU-6215 Sync Lustre external tree with lustre linux kernel client
• is related to: LU-6302 annotations for sparse static analyzer

Comments

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/12207/
Subject: LU-5396 libcfs: make some functions static
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 336f628d5ea17cb0afe26cd966e333e40755b38b

[Frank Zago (Inactive)]

0 -> NULL:
http://review.whamcloud.com/12567

[Frank Zago (Inactive)]

Make some static symbols:
http://review.whamcloud.com/12206
http://review.whamcloud.com/12207
http://review.whamcloud.com/12211
http://review.whamcloud.com/12219
http://review.whamcloud.com/12220
http://review.whamcloud.com/12221
http://review.whamcloud.com/12222
http://review.whamcloud.com/12223

Done for this series. There will a new one once this one is integrated.

[Peter Jones]

A 1000?! The final straight then

[Frank Zago (Inactive)]

Hi Peter, there's quite a few more patches to come.

Number of warnings is down to less to 1000 now.

[Peter Jones]

Frank

I see that all the present patches tracked under this ticket have landed. Are there more to come or can we now close this ticket?

Peter

[Frank Zago (Inactive)]

Add __user annotations (same as above, but 1 patch per branch)
http://review.whamcloud.com/11817 (upstream)
http://review.whamcloud.com/11818 (upstream)
http://review.whamcloud.com/11819 (upstream)
http://review.whamcloud.com/11820 (upstream)
http://review.whamcloud.com/11821 (upstream)
http://review.whamcloud.com/11822 (upstream)
http://review.whamcloud.com/11823 (upstream)
http://review.whamcloud.com/11824 (upstream)

[James A Simmons]

Thank you for doing this. A lot of the upstream kernel Lustre client patches are these types of patches. This will help us move closer to the upstream client for style issues much faster.

[Frank Zago (Inactive)]

Add __user annotations.

http://review.whamcloud.com/11802 (abandoned, see below)
http://review.whamcloud.com/11803 (abandoned, see below)
http://review.whamcloud.com/11804 (abandoned, see below)
http://review.whamcloud.com/11805 (abandoned, see below)
http://review.whamcloud.com/11806 (abandoned, see below)
http://review.whamcloud.com/11807 (abandoned, see below)
http://review.whamcloud.com/11808 (abandoned, see below)
http://review.whamcloud.com/11809 (abandoned, see below)
http://review.whamcloud.com/11810 (abandoned, see below)

[Frank Zago (Inactive)]

Made some functions static:
http://review.whamcloud.com/11305 (upstream)
http://review.whamcloud.com/11306

http://review.whamcloud.com/11255 (upstream)
http://review.whamcloud.com/11256 (upstream)

[Frank Zago (Inactive)]

Locking annotations:
http://review.whamcloud.com/11481 (upstream)
http://review.whamcloud.com/11294 (upstream)
http://review.whamcloud.com/11295