On 07/04/2017 10:14 PM, Ming Lei wrote: > It is observed reading the register from HW takes a bit long, > for example in my box, the following difference of 'perf report > --no-children fio ...' can be seen when running I/O: > > 1) V4.12 without patch > + 9.28% fio [mtip32xx] [k] mtip_irq_handler > + 8.48% fio [mtip32xx] [k] mtip_init_cmd_header > > 2) V4.12 with the following patch > + 9.14% fio [mtip32xx] [k] mtip_irq_handler > ...... > + 1.14% fio [mtip32xx] [k] mtip_init_cmd_header > > IOPS can be increased by ~5% with this patch too.
Thanks, this is definitely problematic since we don't just do it at init time anymore. Applied for 4.13. -- Jens Axboe
