I quickly browsed the patchset, technically looks ok. When you are ready, please push them, and I will try out my tests.
One issue I have is that the behavior is subtly changed vs Linux. In the future, if we port a Linux driver that uses UC- using Linux's well known pgprot_noncached() and MTRR api's to overwrite to WC, it will take just a little more effort (if we notice the subtle difference) to make it work as intended on Akaros (I am not a fan of the spatch approach). Thus, I have a slight preference to see PAT exactly as Linux has (with the change that if you want WT you can have it in PAT4-7), with pgprot_noncached() still using UC-. If you don't think this is important, just go with your current patch set. On Fri, Mar 11, 2016 at 12:00 PM, Barret Rhoden <[email protected]> wrote: > This adds PAT support for write-combining memory mappings. For kernel > memory > mappings, we can use vmap_pmem_writecomb(). For custom memory mappings, > we can > use PTE_WRITECOMB. > > I rebased and touched up Kanoj's commit. If you'd prefer to do that and > work > directly off my last commit (660165), then let me know. > > ------------ > You can also find this patch set at: > > [email protected]:brho/akaros.git > From: 7793cb72c3a0 master > To: 84e2c6919d8c pat > > And view them at: > > https://github.com/brho/akaros/compare/7793cb72c3a0...84e2c6919d8c > > ------------ > > > Barret Rhoden (3): > Stop using PTE_PCD and PTE_PWT directly (XCC) > x86: initialize the PAT MSR > Add write-combining memory mapping mode (XCC) > > Kanoj Sarcar (1): > Implement write combining on x86 > > kern/arch/riscv/ros/mmu.h | 2 ++ > kern/arch/x86/cpuinfo.c | 6 ++++-- > kern/arch/x86/pmap.c | 44 > +++++++++++++++++++++++++++++++++++++++++ > kern/arch/x86/pmap64.c | 2 +- > kern/arch/x86/ros/mmu64.h | 11 ++++++----- > kern/drivers/net/udrvr/compat.c | 19 ++++++++++++++++++ > kern/drivers/net/udrvr/compat.h | 19 ++---------------- > kern/include/mm.h | 1 + > kern/src/mm.c | 5 +++++ > 9 files changed, 84 insertions(+), 25 deletions(-) > > -- > 2.7.0.rc3.207.g0ac5344 > > -- > You received this message because you are subscribed to the Google Groups > "Akaros" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- Thanks, Kanoj -- You received this message because you are subscribed to the Google Groups "Akaros" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. For more options, visit https://groups.google.com/d/optout.
