- removes p_delivermsg_lin item from the process structure and code
related to it
- as the send part, the receive does not need to use the
PHYS_COPY_CATCH() and umap_local() couple.
- The address space of the target process is installed before
delivermsg() is called.
- unlike the linear address, the virtual address does not change when
paging is turned on nor after fork().
- FPU context is stored only if conflict between 2 FPU users or while
exporting context of a process to userspace while it is the active
user of FPU
- FPU has its owner (fpu_owner) which points to the process whose
state is currently loaded in FPU
- the FPU exception is only turned on when scheduling a process which
is not the owner of FPU
- FPU state is restored for the process that generated the FPU
exception. This process runs immediately without letting scheduler
to pick a new process to resolve the FPU conflict asap, to minimize
the FPU thrashing and FPU exception hadler execution
- faster all non-FPU-exception kernel entries as FPU state is not
checked nor saved
- removed MF_USED_FPU flag, only MF_FPU_INITIALIZED remains to signal
that a process has used FPU in the past
- A staging directory is always used to avoid oversized images;
- As a consequence, the zero-filling is removed so no more "out of
space" errors should be printed to the console;
- The root and usr partition sizes are computed so less space should be
wasted (the root partition gets extra 1MB zones and 64 inodes for
run-time though and hardlinks/holes make the used space slightly less
than expected); USRMB (and the new ROOTMB) are now used to enforce
a minimum size rather than set the size;
- TMPDISK1-3 are renamed to more meaningful names (and TMPDISK2 is
dropped because a separate tmp directory is no longer needed);
- The ramdisks are truncated at the end to save memory (not sure
whether it is actually released though).
