On Sat, Mar 6, 2021 at 4:08 PM Syed Nayyar Waris <syednwaris@xxxxxxxxx> wrote: > > This patch reimplements the xgpio_set_multiple() function in > drivers/gpio/gpio-xilinx.c to use the new generic functions: > bitmap_get_value() and bitmap_set_value(). The code is now simpler > to read and understand. Moreover, instead of looping for each bit > in xgpio_set_multiple() function, now we can check each channel at > a time and save cycles. ... > + u32 *const state = chip->gpio_state; > + unsigned int *const width = chip->gpio_width; > + Extra blank line. > + DECLARE_BITMAP(old, 64); > + DECLARE_BITMAP(new, 64); > + DECLARE_BITMAP(changed, 64); > + spin_lock_irqsave(&chip->gpio_lock[0], flags); > + spin_lock(&chip->gpio_lock[1]); I understand why this is done at the top of the function in the original code. I do not understand why you put some operations under spin lock. Have you checked what each of these spin locks protects? Please check and try to lock as minimum as possible. > + bitmap_set_value(old, 64, state[0], width[0], 0); > + bitmap_set_value(old, 64, state[1], width[1], width[0]); > + bitmap_replace(new, old, bits, mask, gc->ngpio); > + > + bitmap_set_value(old, 64, state[0], 32, 0); > + bitmap_set_value(old, 64, state[1], 32, 32); > + state[0] = bitmap_get_value(new, 0, width[0]); > + state[1] = bitmap_get_value(new, width[0], width[1]); > + bitmap_set_value(new, 64, state[0], 32, 0); > + bitmap_set_value(new, 64, state[1], 32, 32); > + bitmap_xor(changed, old, new, 64); Original code and this is cryptic. Can you add a few comments explaining what is going on here? > + spin_unlock(&chip->gpio_lock[1]); > + spin_unlock_irqrestore(&chip->gpio_lock[0], flags); -- With Best Regards, Andy Shevchenko
