- NFS direct IO completely bypasses the buffer and page caches.
If a file is open for direct IO all caching is disabled.
- Direct IO for Directories will be addressed later.
- 2 new NFS directio related sysctls are added. One is a knob to
disable NFS direct IO completely (direct IO is enabled by default).
The other is to disallow mmaped IO on a file that has at least one
O_DIRECT open (see the comment in nfs_vnops.c for more details).
The default is to allow mmaps on a file that has O_DIRECT opens.
Submitted by: Mohan Srinivasan mohans at yahoo-inc dot com
Obtained from: Yahoo!
In such cases, the busying of the page and the unlocking of the
containing object by vm_map_pmap_enter() and vm_fault_prefault() is
unnecessary overhead. To eliminate this overhead, this change
modifies pmap_enter_quick() so that it expects the object to be locked
on entry and it assumes the responsibility for busying the page and
unlocking the object if it must sleep. Note: alpha, amd64, i386 and
ia64 are the only implementations optimized by this change; arm,
powerpc, and sparc64 still conservatively busy the page and unlock the
object within every pmap_enter_quick() call.
Additionally, this change is the first case where we synchronize
access to the page's PG_BUSY flag and busy field using the containing
object's lock rather than the global page queues lock. (Modifications
to the page's PG_BUSY flag and busy field have asserted both locks for
several weeks, enabling an incremental transition.)
pointers to an integer via uintptr_t.
Fix an apparent bug that caused a compile failure.
ieee80211_iterate_nodes() takes ic->ic_sta as its first argument on the
onoe module. It had just 'ic' here in the same context, which was a
mismatched argument.
of a sizeof, need to use %z to get the correct type on all our platforms.
Also, convert integers<->pointers via uintptr_t.
(I think Sam's instructions were for me to commit this. If I
misunderstood, then I apologize in advance.)
- "device sound" does not pull in sound device drivers (like "device
pcm" used to do), so do not mention that option.
- Make the document title more like the title in the other sound
device drivers.
MFC after: 1 week
1. Feature: for flexibility reasons and as a prerequisite to clean
shutdowns, allow the configuration of a stop/shutdown command
via rc.conf variable "jail_<name>_exec_stop" in addition to the
start/boot command (rc.conf variable "jail_<name>_exec_start"). For
backward compatibility reasons, rc.conf variable "jail_<name>_exec"
is still supported, too.
2. Debug: Add the used boot/shutdown commands to the debug output of
the /etc/rc.d/jail script, too.
3. Security: Run the Jail start/boot command in a cleaned environment
to not leak information from the host to the Jail during startup.
4. Feature: Run the Jail stop/shutdown command "jail_<name>_exec_stop" on
"/etc/rc.d/jail stop <name>" to allow a graceful shutdown of the Jail
before its processes are just killed.
5. Bugfix: When killing the remaining Jail processes give the processes
time to actually perform their termination sequence. Without this the
subsequent umount(8) operations usually fail because the resources
are still in use. Additionally, if after trying to TERM-inate the
processes there are still processes hanging around, finally just KILL
them.
6. Bugfix: In rc.shutdown, if running inside a Jail, skip the /etc/rc.d/*
scripts which are flagged with the KEYWORD "nojail" to allow the
correct operation of rc.shutdown under jail_<name>_exec_stop="/bin/sh
/etc/rc.shutdown". This is analogous to what /etc/rc does inside a Jail.
Now the following typical host-configuration for two Jails works as
expected and correctly boots and shutdowns the Jails:
-----------------------------------------------------------
# /etc/rc.conf:
jail_enable="YES"
jail_list="foo bar"
jail_foo_rootdir="/j/foo"
jail_foo_hostname="foo.example.com"
jail_foo_ip="192.168.0.1"
jail_foo_devfs_enable="YES"
jail_foo_mount_enable="YES"
jail_foo_exec_start="/bin/sh /etc/rc"
jail_foo_exec_stop="/bin/sh /etc/rc.shutdown"
jail_bar_rootdir="/j/bar"
jail_bar_hostname="bar.example.com"
jail_bar_ip="192.168.0.2"
jail_bar_devfs_enable="YES"
jail_bar_mount_enable="YES"
jail_bar_exec_start="/path/to/kjailer -v"
jail_bar_exec_stop="/bin/sh -c 'killall kjailer && sleep 60'"
-----------------------------------------------------------
# /etc/fstab.foo
/v/foo /j/foo/v/foo nullfs rw 0 0
-----------------------------------------------------------
# /etc/fstab.bar
/v/bar /j/bar/v/bar nullfs rw 0 0
-----------------------------------------------------------
Reviewed by: freebsd-hackers
MFC after: 2 weeks
nice of 0. Doing so can cause an infinite loop because they should be
running, but a nice -20 process could prevent them from doing so.
- Add a new flag KEF_PRIOELEV to flag a thread that has had its priority
elevated due to priority propagation. If a thread has had its priority
elevated, we assume that it must go on the current queue and it must
get a slice.
- In sched_userret() if our priority was elevated and we shouldn't have
a timeslice, yield here until we should.
Found/Tested by: glebius
