[PATCH] um: implement flush_cache_vmap/flush_cache_vunmap

[Johannes Berg]

On Tue, 2021-03-16 at 08:46 +0000, Anton Ivanov wrote:
> 
> Well spotted.
> 
> Unless I am mistaken, there may be a slightly better way of doing it.
> 
> We can implement arch_sync_kernel_mappings() and sync only where the
> page modified mask says so by setting ARCH_PAGE_TABLE_SYNC_MASK
> 
> This way flush_cache_* can remain nops as in asm-generic

Would that actually buy us anything?

Not that I mind, or even understand the TLB code well, but it seems
fairly similar?

> I am going to give that a spin, if it works, I will post it to the list by lunchtime GMT

Sounds good to me :)

I also made these patches:

https://lore.kernel.org/lkml/20210315235453.e3fbb86e99a0.I08a3ee6dbe47ea3e8024956083f162884a958e40@changeid/T/#u


so my "vmalloc-heavy workload" no longer is vmalloc heavy since it now
uses kvmalloc and never hits vmalloc, always kmalloc :)

johannes