to the build.
This allocator uses a binary buddy system with a twist. First and
foremost, this allocator is required to support the implementation of
superpages. As a side effect, it enables a more robust implementation
of contigmalloc(9). Moreover, this reimplementation of
contigmalloc(9) eliminates the acquisition of Giant by
contigmalloc(..., M_NOWAIT, ...).
The twist is that this allocator tries to reduce the number of TLB
misses incurred by accesses through a direct map to small, UMA-managed
objects and page table pages. Roughly speaking, the physical pages
that are allocated for such purposes are clustered together in the
physical address space. The performance benefits vary. In the most
extreme case, a uniprocessor kernel running on an Opteron, I measured
an 18% reduction in system time during a buildworld.
This allocator does not implement page coloring. The reason is that
superpages have much the same effect. The contiguous physical memory
allocation necessary for a superpage is inherently colored.
Finally, the one caveat is that this allocator does not effectively
support prezeroed pages. I hope this is temporary. On i386, this is
a slight pessimization. However, on amd64, the beneficial effects of
the direct-map optimization outweigh the ill effects. I speculate
that this is true in general of machines with a direct map.
Approved by: re
caches with data caches after writing to memory. This typically
is required to make breakpoints work on ia64 and powerpc. For
those architectures the function is implemented.
This patch fixes places where they should be called atomically changing
their locking requirements (both assume per-proc spinlock held) and
introducing rufetchcalc which wrappers both calls to be performed in
atomic way.
Reviewed by: jeff
Approved by: jeff (mentor)
in tcp_outout(). This is currently not strictly necessary but paves
the way to simplify the entire SYN options handling quite a bit.
Clarify comment. No change in effective behavour with this commit.
RFC1323 requires the window field in a SYN (i.e., a <SYN> or
<SYN,ACK>) segment itself never be scaled.
and simplify handling of the send/receive window scaling. No
change in effective behavour.
RFC1323 requires the window field in a SYN (i.e., a <SYN> or
<SYN,ACK>) segment itself never be scaled.
Noticed by: yar
- Unsafeness on ruadd() in thread_exit()
- Unatomicity of thread_exiit() in the exit1() operations
This patch addresses these problems allocating p_fd as part of the
process and modifying the way it is accessed.
A small chunk of this patch, resolves a race about p_state in kern_wait(),
since we have to be sure about the zombif-ing process.
Submitted by: jeff
Approved by: jeff (mentor)
a timer issues a shutdown and a simultaneous close on the socket
happens. This race condition is inherent in the current socket/
inpcb life cycle system but can be handled well.
Reported by: kris
Tested by: kris (on 8-core machine)
- Reorder send failed to be in correct order.
- Fixed calulation of init-ack to be right off
mbuf lengths instead of the precalculated value. This
will fix one 64 bit platform issue.
error doing so. It seems an increasing number of phones have this
quirk, and we're not keeping up. There appears to be nothing bad that
happens for non-quirked phones.
Minor cleanups:
o prefer device_printf over printf
o kill devinfo stuff
o minor other preening.
need to do it at all anymore. Remove it from here. Expand
USB_ATTACH_SETUP inline now that it is one line and we're moving away
from the compat macros. Remove some bzero calls that turn out not be
be necessary.
Correct long-standing off-by-one error in -W option.
Submitted by: edwin@
Shorten some long lines. These files are still not completely
style(9) compliant.
what we print, don't print it anymore. And don't compute it anymore.
And don't malloc/free memory for it anymore. While I'm here, prefer
device_printf where appropriate.
the value of ph_nhooks to zero, not the address. This removes
extranious calls to pfil_run_hooks (and an rw lock) from the
network stack's critical path when no pfil hooks are active.
Reviewed by: csjp
Sponsored by: Myricom Inc.
implementing some of them using existing ones.
- Allow to compile ZFS on all archs and use atomic operations surrounded
by global mutex on archs we don't have or can't have all atomic
operations needed by ZFS.
algoritm would not go through the proper initialization.
- The initialization was incorrect as well, causing problems in
sat networks with > 1sec RTT
- Get rid of magic numbers in RTT calculations.
