Messages in this thread | | | Date | Tue, 14 Apr 2020 14:56:05 +0300 | From | Dan Carpenter <> | Subject | Re: [PATCH 5/8] staging: rtl8188eu: Remove function rtw_modular64() |
| |
On Sun, Apr 12, 2020 at 04:34:08PM +0300, Ivan Safonov wrote: > > Remove function rtw_modular64 as all it does is call do_div. > > This is wrong. Macro do_div(x, y) change first argument x, but > rtw_modular64(x, y) preserve it. > > > + tsf = pmlmeext->TSFValue - do_div(pmlmeext->TSFValue, (pmlmeinfo->bcn_interval*1024)) - 1024; /* us */ > > rounddown(pmlmeext->TSFValue, pmlmeinfo->bcn_interval * 1024) - 1024 > is a better replacement for
You're absolutely correct that the patch is buggy, but I'm not sure that rounddown() is what we want.
rtw_modular64() took the MOD of x. So it should be something like:
tsf = pmlmeext->TSFValue - (pmlmeext->TSFValue % (pmlmeinfo->bcn_interval * 1024)) - 1024; /* us */
But what the heck is that even??? If pmlmeinfo->bcn_interval is zero or one then the subtraction ends up giving us a negative.
regards, dan carpenter
| |