- unify two copies of code to extend a chain.
- when extending a chain,
- use trailing space of the last mbuf if any.
- use mbuf cluster if appropriate.
- don't use managed mappings/backing objects for wired memory allocations.
save some resources like pv_entry. also fix (most of) PR/27030.
- simplify kernel memory management API.
- simplify pmap bootstrap of some ports.
- some related cleanups.
for consistency with M_FREE() and m_freem(). Affected files:
sys/mbuf.h
kern/uipc_socket2.c
kern/uipc_mbuf.c
net/if_ethersubr.c
netatalk/ddp_input.c
nfs/nfs_socket.c
Gone are the old kern_sysctl(), cpu_sysctl(), hw_sysctl(),
vfs_sysctl(), etc, routines, along with sysctl_int() et al. Now all
nodes are registered with the tree, and nodes can be added (or
removed) easily, and I/O to and from the tree is handled generically.
Since the nodes are registered with the tree, the mapping from name to
number (and back again) can now be discovered, instead of having to be
hard coded. Adding new nodes to the tree is likewise much simpler --
the new infrastructure handles almost all the work for simple types,
and just about anything else can be done with a small helper function.
All existing nodes are where they were before (numerically speaking),
so all existing consumers of sysctl information should notice no
difference.
PS - I'm sorry, but there's a distinct lack of documentation at the
moment. I'm working on sysctl(3/8/9) right now, and I promise to
watch out for buses.
* m_apply(), which applies a function to each mbuf in chain
starting at a specified offset, for a specified length.
* m_getptr(), which returns a pointer to the mbuf, as well as
the offset into that mbuf, corresponding to an offset from
the beginning of an mbuf chain.
From OpenBSD, cleaned up slightly by me.
in the mbuf header.
* Use the new cached paddr feature of the pool_cache API to record
the physical address of mbuf clusters. (We cannot use a ctor for
clusters, since clusters have no constructed form; they are merely
buffers).
Bus_dma back-ends may use the cached physical addresses to save having to
extract the physical address from virtual.
* Provide space in m_ext recording the vm_page *'s for an SOSEND_LOAN_CHUNK-
sized non-cluster external buffer. Use this in the sosend_loan code to
save having to extract the physical address from virtual and then look
up the vm_page *'s.
* Provide an indication that an external buffer is mapped read-only at
the MMU. Set this flag for the external buffer in the sosend_loan
case, since loaned pages are always mapped read-only. Bus_dma back-ends
may use this information to save cache flushing, since a cache flush of
a read-only mapping is redundant on some architectures (the cache would
have already been flushed when making the mapping read-only).
Part 2 in a series of simple patches contributed by Wasabi Systems
to improve network performance.
Do a little mbuf rework while here. Change all uses of MGET*(*, M_WAIT, *)
to m_get*(M_WAIT, *). These are not performance critical and making them
call m_get saves considerable space. Add m_clget analogue of MCLGET and
make corresponding change for M_WAIT uses.
Modify netinet, gem, fxp, tulip, nfs to support MBUFTRACE.
Begin to change netstat to use sysctl.
malloc types into a structure, a pointer to which is passed around,
instead of an int constant. Allow the limit to be adjusted when the
malloc type is defined, or with a function call, as suggested by
Jonathan Stone.
