On Mon, Feb 20, 2017 at 04:24:50PM -0800, Bryan Drewery wrote: > On 2/17/2017 7:40 AM, Mateusz Guzik wrote: > > Author: mjg > > Date: Fri Feb 17 15:40:24 2017 > > New Revision: 313878 > > URL: https://svnweb.freebsd.org/changeset/base/313878 > > > > Log: > > mtx: get rid of file/line args from slow paths if they are unused > > > > This denotes changes which went in by accident in r313877. > > I really wish people would just revert their changes and recommit them > properly. The 'svn blame' on the code in r313877 will never show the > commit message here (r313878). So a person would only find this > explanation if they read 'svn log' on the file, which in the case of > sys/kern/kern_mutex.c there are 273 commits for. Are we expected to > read 'svn log' (in the future) for all changes in the hopes that a later > commit happens to mention it? > > As someone who so often is 'svn blame'ing code to understand it better > and to track regressions, commits like this that explain other commits > might as well have never been done. >
In general I agree, but also don't think the change was worth any additional churn. It only removed 2 args when not under LOCK_DEBUG. The commit message above is only to note KBI is covered as this could be of concern for a casual reader. I would not do this if the change was doing anything non-trivial. > > > > On most production kernels both said parameters are zeroed and have > > nothing > > reading them in either __mtx_lock_sleep or __mtx_unlock_sleep. Thus this > > change > > stops passing them by internal consumers which this is the case. > > > > Kernel modules use _flags variants which are not affected kbi-wise. > > > > Modified: > > head/sys/kern/kern_mutex.c > > > > Modified: head/sys/kern/kern_mutex.c > > ============================================================================== > > --- head/sys/kern/kern_mutex.c Fri Feb 17 15:34:40 2017 > > (r313877) > > +++ head/sys/kern/kern_mutex.c Fri Feb 17 15:40:24 2017 > > (r313878) > > @@ -622,7 +622,7 @@ __mtx_lock_sleep(volatile uintptr_t *c, > > LOCKSTAT_RECORD1(adaptive__block, m, sleep_time); > > > > /* > > - * Only record the loops spinning and not sleeping. > > + * Only record the loops spinning and not sleeping. > > */ > > if (lda.spin_cnt > sleep_cnt) > > LOCKSTAT_RECORD1(adaptive__spin, m, all_time - sleep_time); > > > > > -- > Regards, > Bryan Drewery > -- Mateusz Guzik <mjguzik gmail.com> _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
