[LU-555] ll_have_md_lock() code optimization

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.2.0
• Affects Version/s: Lustre 2.1.0
• Assignee: Peter Jones
• Reporter: CEA

Description

Suggested by Andreas:
in ll_md_blocking_ast(), Instead of doing multiple searches for these lock bits, it makes more sense to change ll_have_md_lock() to take "&bits" as the parameter (instead of a specific single bit), and then it can do a search on the first bit in the mask. If any lock is found, it can zero out all of the set lock bits in the lock from "&bits".

In the common case where there are multiple bits set in the lock this will avoid calling ll_have_md_lock->md_lock_match() multiple times for each file.

Issue Links

• Trackbacks: Changelog 2.2 version 2.2.0 Support for networks: o2iblnd OFED 1.5.4 Server support for kernels: 2.6.32220.4.2.el6 (RHEL6) Client support for unpatched kernels: 2.6.18274.18.1.el5 (RHEL5) 2.6.32220.4.2.el6 (RHEL6) 2.6.32.360....