On Thu, May 28, 2020 at 12:59:17PM -0700, Sean Christopherson wrote: > On Thu, May 28, 2020 at 10:07:18PM +0300, Jarkko Sakkinen wrote: > > On Thu, May 28, 2020 at 07:16:35PM +0200, Borislav Petkov wrote: > > > Lemme reply to all mails with one. :-) > > > And except those last two. Those are allocating a page from the EPC > > > sections so I'd call them: > > > > > > sgx_try_alloc_page -> sgx_alloc_epc_page_section > > > __sgx_try_alloc_page -> __sgx_alloc_epc_page_section > > > > > > former doing the loop, latter doing the per-section list games. > > > > sgx_alloc_epc_page_section() is a bit nasty and long name to use for > > grabbing a page. And even the documentation spoke about grabbing before > > this naming discussion. I think it is a great description what is going > > on. Everytime I talk about the subject I talk about grabbing. > > Lets just say that your suggestion, I could not use in a conference > > talk as a verb when I describe what is going on. That function > > signature does not fit to my mouth :-) I would talk about > > grabbing a page. > > "allocate an EPC page from the specified section" > > It also works if/when we add NUMA awareness, e.g. sgx_alloc_epc_page_node() > means "allocate an EPC page from the specified node". Note that I'm not > inventing these from scratch, simply stealing them from alloc_pages() and > alloc_pages_node(). The section thing is unique to SGX, but the underlying > concept is the same.
Then it should be sgx_alloc_epc_page_from_section() if you go with that. Otherwise it is mixes too much with the section. I did read these mails first quickly and first thought that functions were doing something with sgx_epc_section and not with pages. Only with a deeper look that it's the name for allocating a page. I think both names are waste of screen estate. Too long. > > * sgx_grab_page() - Grab a free EPC page > > * @owner: the owner of the EPC page > > * @reclaim: reclaim pages if necessary > > * > > * Iterate through EPC sections and borrow a free EPC page to the caller. > > When a > > * page is no longer needed it must be released with sgx_free_page(). If > > * @reclaim is set to true, directly reclaim pages when we are out of > > pages. No > > * mm's can be locked when @reclaim is set to true. > > * > > * Finally, wake up ksgxswapd when the number of pages goes below the > > watermark > > * before returning back to the caller. > > * > > * Return: > > * an EPC page, > > * -errno on error > > */ > > > > I also rewrote the kdoc. > > > > I do agree that sgx_try_grab_page() should be renamed as __sgx_grab_page(). > > FWIW, I really, really dislike "grab". The nomenclature for normal memory > and pages uses "alloc" when taking a page off a free list, and "grab" when > elevating the refcount. I don't understand the motivation for diverging > from that. SGX is weird enough as is, using names that don't align with > exist norms will only serve to further obfuscate the code. OK, what would be a better name then? The semantics are not standard memory allocation semantics in the first place. And kdoc in v30 speaks about grabbing. /Jarkko
