linux-stable/include
Paul E. McKenney 803b0ebae9 time: RCU permitted to stop idle entry via softirq
The can_stop_idle_tick() function complains if a softirq vector is
raised too late in the idle-entry process, presumably in order to
prevent dangling softirq invocations from being delayed across the
full idle period, which might be indefinitely long -- and if softirq
was asserted any later than the call to this function, such a delay
might well happen.

However, RCU needs to be able to use softirq to stop idle entry in
order to be able to drain RCU callbacks from the current CPU, which in
turn enables faster entry into dyntick-idle mode, which in turn reduces
power consumption.  Because RCU takes this action at a well-defined
point in the idle-entry path, it is safe for RCU to take this approach.

This commit therefore silences the error message that is sometimes
produced when the going-idle CPU suddenly finds that it has an RCU_SOFTIRQ
to process.  The error message will continue to be issued for other
softirq vectors.

Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2012-09-23 07:42:52 -07:00
..
acpi Merge branches 'delete-gts-bfs', 'misc', 'novell-bugzilla-757888-numa' and 'osc-pcie' into base 2012-08-03 00:31:23 -04:00
asm-generic mutex: Place lock in contended state after fastpath_lock failure 2012-08-13 18:46:54 +02:00
crypto
drm drm: Check for invalid cursor flags 2012-08-24 09:38:40 +10:00
keys
linux time: RCU permitted to stop idle entry via softirq 2012-09-23 07:42:52 -07:00
math-emu
media
memory
misc
mtd
net Merge branch 'master' of git://1984.lsi.us.es/nf 2012-08-31 13:06:37 -04:00
pcmcia
ras
rdma
rxrpc
scsi
sound ASoC: Additional updates for 3.6 2012-08-20 21:26:04 +02:00
target target: Remove unused se_cmd.cmd_spdtl 2012-08-21 14:27:35 -07:00
trace Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-08-03 10:57:20 -07:00
video
xen Revert "xen PVonHVM: move shared_info to MMIO before kexec" 2012-08-16 13:05:25 -04:00
Kbuild