On Fri, Oct 18, 2024 at 08:38:22PM +0100, Al Viro wrote: > On Fri, Oct 18, 2024 at 05:51:58PM +0100, Al Viro wrote: > > > Extra cycles where? If anything, I'd expect a too-small-to-measure > > speedup due to dereference shifted from path_init() to __set_nameidata(). > > Below is literally all it takes to make filename_lookup() treat NULL > > as empty-string name. > > > > NOTE: I'm not talking about forcing the pure by-descriptor case through > > the dfd+pathname codepath; not without serious profiling. But treating > > AT_FDCWD + NULL by the delta below and passing NULL struct filename to > > filename_lookup()? Where do you expect to have the lost cycles on that? > > [snip] > > BTW, could you give me a reference to the mail with those objections? > I don't see anything in my mailbox, but... I had to search for quite a bit myself: https://lore.kernel.org/r/CAHk-=wifPKRG2w4mw+YchNtAuk4mMJBde7bG-Z7wt0+ZeQMJ_A@xxxxxxxxxxxxxx
