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Diffstat (limited to 'open_issues/user-space_device_drivers.mdwn')
| -rw-r--r-- | open_issues/user-space_device_drivers.mdwn | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/open_issues/user-space_device_drivers.mdwn b/open_issues/user-space_device_drivers.mdwn index b8061f71..e929f2bf 100644 --- a/open_issues/user-space_device_drivers.mdwn +++ b/open_issues/user-space_device_drivers.mdwn @@ -33,6 +33,16 @@ Also see [[device drivers and IO systems]]. to IRQs. However, at least in GNU Mach, that code (`kern/eventcount.c`) doesn't seem functional at all and isn't integrated properly in the kernel. + * IRC, freenode, #hurd, 2011-07-29 + + < antrik> regarding performance of userspace drivers, there is one + thing that really adds considerable overhead: interrupt + handling. whether this is relevant very much depends on the hardware + in question. when sending many small packets over gigabit ethernet, + it might be noticable; in most other cases it's irrelevant + < youpi> some cards support interrupt coalescin + < youpi> could be supported by DDE too + ## DMA * Security considerations. @@ -52,6 +62,32 @@ Also see [[device drivers and IO systems]]. * [[GNU Mach|microkernel/mach/gnumach]] is said to have a high overhead when doing RPC calls. +## System Boot + +IRC, freenode, #hurd, 2011-07-27 + + < braunr> btw, was there any formulation of the modifications required to + have disk drivers in userspace ? + < braunr> (which would obviously need something like + initrd/initramfs/whatever and may also need the root file system not to + be the first task started) + < braunr> hm actually, we may not need initrd + < braunr> the boot loader could just load more modules + < antrik> braunr: I have described all that in my thesis report... in + German :-( + < braunr> and the boot scripts could be adjusted to pass around the right + ports + < Tekk_> braunr: yeah, we could probably load a module that kciks us into + userspace and starts the disk driver + < braunr> modules are actualy userspace executables + < Tekk_> ah + < Tekk_> so what's the issue? + < Tekk_> oh! I'm thinking the ext2fs server, which is already in userspce + < braunr> change the file systems to tell them which underlying disk driver + to use + < Tekk_> mhm + < braunr> s/disk/storage/ + # Plan |