> >> Am 28.12.2016 um 03:59 schrieb Yu, Xiangliang: > >>>> -----Original Message----- > >>>> From: amd-gfx [mailto:amd-gfx-bounces at lists.freedesktop.org] On > >>>> Behalf Of zhoucm1 > >>>> Sent: Wednesday, December 28, 2016 10:32 AM > >>>> To: Yu, Xiangliang <Xiangliang.Yu at amd.com>; amd- > >>>> gfx at lists.freedesktop.org > >>>> Cc: Liu, Monk <Monk.Liu at amd.com> > >>>> Subject: Re: [V2 1/1] drm/amdgpu/gfx8: add support kernel interface > >>>> queue(KIQ) > >>>> > >>>> > >>>> > >>>> On 2016å¹´12æ??28æ?¥ 10:27, Yu, Xiangliang wrote: > >>>>> + > >>>>>> + amdgpu_bo_kunmap(kiq->eop_obj); > >>>>>> + > >>>> I see it is in many places, which is don't need I think, > >>>> amdgpu_bo_free_kernel will handle it if I'm correct. > >>> Memory kmap should be free ASAP from memory management point. > >> No, that is completely unnecessary as long as you don't run a 32bit > >> system with tight address space. > > We can't decide what OS to use. I agree with monk's comment that better > to unmap it if cpu don't use. > > No it isn't. As I said this is only necessary on 32bit systems with tight address > space. In other words we simply don't really support that configuration any > more. > > If you don't need it then why do you want to kmap it in the first place? > In my patch, first get mqd address to fill out mqd context through kmap, then setup compute queue with kiq ring. And I see there are lot of similar usage in amdgpu, for example, gfx_v8_0_rlc_init function. Could you help to explain it?
