On Mon, Aug 07, 2023 at 09:26:54AM +0800, zhangshida wrote: > From: Shida Zhang <zhangshida@xxxxxxxxxx> > > Following Andreas' suggestion, it is time to adapt these helpers > to handle larger records during runtime, especially in preparation > for the eventual support of ext4 with a block size greater than > PAGE_SIZE. Is there a reason for landing this now? We don't have support for block_size > PAGE_SIZE yet, and this patch doesn't come for free, at least not systems with page_size < 64k. These inline functions are *very* hot and get used in a large number of places. Have you looked to see what it might do to text size of the ext4 code? And whether the expansion to the icache might actually impact performance on CPU bound workloads with very large directories? I will note that there are some opportunities to optimize how often we use ext4_rec_len_from_disk. For example, it gets called from ext4_check_dir_entry(), and often the callers of that function will need the directory record length. So having ext4_check_dir_entry() optionally fill in the rec_len via a passed-in pointer might be worthwhile. Cheers, - Ted
