- Trade off granularity to reduce overhead, since the current model
doesn't appear to reduce contention substantially: move to a single
harvest mutex protecting harvesting queues, rather than one mutex
per source plus a mutex for the free list.
- Reduce mutex operations in a harvesting event to 2 from 4, and
maintain lockless read to avoid mutex operations if the queue is
full.
- When reaping harvested entries from the queue, move all entries from
the queue at once, and when done with them, insert them all into a
thread-local queue for processing; then insert them all into the
empty fifo at once. This reduces O(4n) mutex operations to O(2)
mutex operations per wakeup.
In the future, we may want to look at re-introducing granularity,
although perhaps at the granularity of the source rather than the
source class; both the new and old strategies would cause contention
between different instances of the same source (i.e., multiple
network interfaces).
Reviewed by: markm
reaching into the socket buffer. This prevents a number of potential
races, including dereferencing of sb_mb while unlocked leading to
a NULL pointer deref (how I found it). Potentially this might also
explain other "odd" TCP behavior on SMP boxes (although haven't
seen it reported).
RELENG_5 candidate.
and make it visible (same way as in OpenBSD). Describe usage in manpage.
This change is useful for creating custom free methods, which
call default free method at their end.
While here, make malloc declaration for mbuf tags more informative.
Approved by: julian (mentor), sam
MFC after: 1 month
when the spin lock in question isn't -- it's the critical_enter() that
KDB set. No more panic in DDB for console -> syscons -> tty -> knote
operations.
be used to announce various system activity.
The auxio device provides auxiliary I/O functions and is found on various
SBus/EBus UltraSPARC models. At present, only front panel LED is
controlled by this driver.
Approved by: jake (mentor)
Reviewed by: joerg
Tested by: joerg
state management corruption, mbuf leaks, general mbuf corruption,
and at least on i386 a first level splash damage radius that
encompasses up to about half a megabyte of the memory after
an mbuf cluster's allocation slab. In short, this has caused
instability nightmares anywhere the right kind of network traffic
is present.
When the polymorphic refcount slabs were added to UMA, the new types
were not used pervasively. In particular, the slab management
structure was turned into one for refcounts, and one for non-refcounts
(supposed to be mostly like the old slab management structure),
but the latter was almost always used through out. In general, every
access to zones with UMA_ZONE_REFCNT turned on corrupted the
"next free" slab offset offset and the refcount with each other and
with other allocations (on i386, 2 mbuf clusters per 4096 byte slab).
Fix things so that the right type is used to access refcounted zones
where it was not before. There are additional errors in gross
overestimation of padding, it seems, that would cause a large kegs
(nee zones) to be allocated when small ones would do. Unless I have
analyzed this incorrectly, it is not directly harmful.
with acpi but the timer runs twice as fast. Note that the main problem
(system doesn't work properly with acpi disabled) should be fixed separately.
Changes:
* Add a quirk to disable the timer
* Merge the P5A and P5A-B quirks since they appear to be based on the
same ASL.
PR: i386/72450
Tested by: Kevin Oberman <oberman es.net>
MFC after: 3 days
We return ENOBUF to indicate the problem, which is an errno that should be
handled well everywhere.
Requested & Submitted by: green
Silently okay'ed by: The rest of the firewall gang
MFC after: 3 days
Restructure pmap_enter() to prevent the loss of a page modified (PG_M) bit
in a race between processors. (This restructuring assumes the newly atomic
pte_load_store() for correct operation.)
Reviewed by: tegge@
PR: i386/61852
problem I had but it's happening in code that is messing around with
register windows - I'm willing to live with that piece being sensitive
to this and it looks like the other problems we had reported lately
are not fixed by using -O instead of -O2.
Sorry for the churn. Looks like I need a second pointy hat. Someone
tells me they stack well. :-))))
This also adds support for bigger disks on the controller I have access to,
and maybe others if I understood the adhoc methods used on those.
Those with more PC98 bigdrive controllers it is hereby invited to add/fix
support for those in geom_pc98.c and not using #ifdef PC98 all over the place.
callouts as non-CALLOUT_MPSAFE. Otherwise, they may trigger an
assertion regarding Giant if they enter other parts of the stack from
the callout.
MFC after: 3 days
Reported by: Dikshie < dikshie at ppk dot itb dot ac dot id >
-O2 on kernel compiles after all. While working on adding a KASSERT
to sparc64/sparc64/rwindow.c I found that it was "position sensitive",
putting it above a call to flushw() instead of below caused corruption
of processes on the system. jake and jhb have both confirmed there is
no obvious explanation for that. The exact same kernel code does not
have the process corruption problem if compiled with -O instead of -O2.
There have been signs of similar issues floated on the sparc64@ mailing
list, lets see if this helps make them go away.
Note this isn't an optimal fix as far as the file format goes, if this
disgusts too many people I'll fix it the right way. Since compiling
with something other than -O is a known problem this format would prevent
a change to the default causing grief. And this may also help motivate
finding out what the compiler is doing wrong so we can shift back to
using -O2. :-)
My turn for the pointy hat... One of the florescent ones...
MFC after: 2 days
After some discussion the best option seems to be to signal the thread's
death from within the kernel. This requires that thr_exit() take an
argument.
Discussed with: davidxu, deischen, marcel
MFC after: 3 days