As a general overview, the series of patches in the mail thread do match their description. The addition of the stricter, explicit use of instrumentation does improve the design as the distinction of the use cases requiring a pin or a lock is made more clear. The added commentary is descriptive and appears grammatically correct, at least to a non native speaker.
Unfortunately though, the two bug fixes do not seem to apply. Also, there is a small issue regarding the process, not the content of the patches. In CF app there is a latest attachment (v3-0002-Add-nbtree-Valgrind-buffer-lock-checks.patch) which does not appear in the mail thread. Before changing the status, I will kindly ask for the complete latest series that applies in the mail thread. The new status of this patch is: Waiting on Author