The stop machine logic can lock up if all but one of the migration
threads make it through the disable-irq step and the one remaining
thread gets stuck in __do_softirq. The reason __do_softirq can hang is
that it has a bail-out based on jiffies timeout, but in the lockup case,
jiffies itself is not incremented.
To work around this, re-add the max_restart counter in __do_irq and stop
processing irqs after 10 restarts.
Thanks to Tejun Heo and Rusty Russell and others for helping me track
this down.
This was introduced in 3.9 by commit c10d73671a ("softirq: reduce
latencies").
It may be worth looking into ath9k to see if it has issues with its irq
handler at a later date.
The hang stack traces look something like this:
------------[ cut here ]------------
WARNING: at kernel/watchdog.c:245 watchdog_overflow_callback+0x9c/0xa7()
Watchdog detected hard LOCKUP on cpu 2
Modules linked in: ath9k ath9k_common ath9k_hw ath mac80211 cfg80211 nfsv4 auth_rpcgss nfs fscache nf_nat_ipv4 nf_nat veth 8021q garp stp mrp llc pktgen lockd sunrpc]
Pid: 23, comm: migration/2 Tainted: G C 3.9.4+ #11
Call Trace:
<NMI> warn_slowpath_common+0x85/0x9f
warn_slowpath_fmt+0x46/0x48
watchdog_overflow_callback+0x9c/0xa7
__perf_event_overflow+0x137/0x1cb
perf_event_overflow+0x14/0x16
intel_pmu_handle_irq+0x2dc/0x359
perf_event_nmi_handler+0x19/0x1b
nmi_handle+0x7f/0xc2
do_nmi+0xbc/0x304
end_repeat_nmi+0x1e/0x2e
<<EOE>>
cpu_stopper_thread+0xae/0x162
smpboot_thread_fn+0x258/0x260
kthread+0xc7/0xcf
ret_from_fork+0x7c/0xb0
---[ end trace 4947dfa9b0a4cec3 ]---
BUG: soft lockup - CPU#1 stuck for 22s! [migration/1:17]
Modules linked in: ath9k ath9k_common ath9k_hw ath mac80211 cfg80211 nfsv4 auth_rpcgss nfs fscache nf_nat_ipv4 nf_nat veth 8021q garp stp mrp llc pktgen lockd sunrpc]
irq event stamp: 835637905
hardirqs last enabled at (835637904): __do_softirq+0x9f/0x257
hardirqs last disabled at (835637905): apic_timer_interrupt+0x6d/0x80
softirqs last enabled at (5654720): __do_softirq+0x1ff/0x257
softirqs last disabled at (5654725): irq_exit+0x5f/0xbb
CPU 1
Pid: 17, comm: migration/1 Tainted: G WC 3.9.4+ #11 To be filled by O.E.M. To be filled by O.E.M./To be filled by O.E.M.
RIP: tasklet_hi_action+0xf0/0xf0
Process migration/1
Call Trace:
<IRQ>
__do_softirq+0x117/0x257
irq_exit+0x5f/0xbb
smp_apic_timer_interrupt+0x8a/0x98
apic_timer_interrupt+0x72/0x80
<EOI>
printk+0x4d/0x4f
stop_machine_cpu_stop+0x22c/0x274
cpu_stopper_thread+0xae/0x162
smpboot_thread_fn+0x258/0x260
kthread+0xc7/0xcf
ret_from_fork+0x7c/0xb0
Signed-off-by: Ben Greear <greearb@candelatech.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Pekka Riikonen <priikone@iki.fi>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In (bc6bcb5 netfilter: xt_TCPOPTSTRIP: fix possible mangling beyond
packet boundary), the use of tcp_hdr was introduced. However, we
cannot assume that skb->transport_header is set for non-local packets.
Cc: Florian Westphal <fw@strlen.de>
Reported-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Having both modes can be beneficial for video playback cases. If you can
match the video framerate exactly, and the audio and video clocks come
from the same source, you should be able to avoid dropped/repeated
frames without expensive operations such as resampling the audio to
match video output rate.
Rather than add both variants based on the CEA extension short video
descriptors in do_cea_modes(), add only one variant there. Once all
the EDID has been fully probed, do a loop over the entire probed mode
list, during which we add the other variants for all modes that match
CEA modes. This allows us to match modes that didn't come via the CEA
short video descriptors. For example one Samsung TV here doesn't have
the 640x480-60 mode as a SVD, but instead it's specified via a detailed
timing descriptor.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
We want to disable the cursor by calling ->cursor_set() with handle=0
from places where we don't have a file_priv, so don't try to access it
unless necessary.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Daniel writes:
Another round of drm-intel-next for 3.11. Highlights:
- Haswell IPS support (Paulo Zanoni)
- VECS support on Haswell (Ben Widawsky, Xiang Haihao, ...)
- Haswell watermark fixes (Paulo Zanoni)
- "Make the gun bigger again" multithread fence fix from Chris.
- i915_error_state finnally no longer fails with -ENOMEM! Big thanks to
Mika for tackling this.
- vlv sideband locking fixes from Jani
- Hangcheck prep work for arb_robustness support (Mika&Chris)
- edp vs cpu port confusion clean-up from Imre
- pile of smaller fixes and cleanups all over.
* tag 'drm-intel-next-2013-06-01' of git://people.freedesktop.org/~danvet/drm-intel: (70 commits)
drm/i915: add i915_ips_status debugfs entry
drm/i915: add enable_ips module option
drm/i915: implement IPS feature
drm/i915: fix up the edp power well check
drm/i915: add I915_PARAM_HAS_VEBOX to i915_getparam
drm/i915: add I915_EXEC_VEBOX to i915_gem_do_execbuffer()
drm/i915: add VEBOX into debugfs
drm/i915: Enable vebox interrupts
drm/i915: vebox interrupt get/put
drm/i915: consolidate interrupt naming scheme
drm/i915: Convert irq_refounct to struct
drm/i915: make PM interrupt writes non-destructive
drm/i915: Add PM regs to pre/post install
drm/i915: Create an ivybridge_irq_preinstall
drm/i915: Create a more generic pm handler for hsw+
drm/i915: add support for 5/6 data buffer partitioning on Haswell
drm/i915: properly set HSW WM_LP watermarks
drm/i915: properly set HSW WM_PIPE registers
drm/i915: fix pch_nop support
drm/i915: Vebox ringbuffer init
...
Keeping the modes sorted by vrefresh before the pixel clock makes the
mode list somehow more pleasing to the eye.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Keeping the modes in the same order as we probe them makes it a bit
easier to track what's happening.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Preserve the destination mode's list head in drm_mode_copy. Just
in case someone decides that it's a good idea to overwrite a mode which
happens to be on some list,
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
If the current rate of parent clock is sufficient to provide child a
requested rate with a proper divider setting, the rate change request
should not be propagated. Instead, changing the divider setting is good
enough to get child clock run at the requested rate.
On an imx6q clock configuration illustrated below,
ahb --> ipg --> ipg_per
132M 66M 66M
calling clk_set_rate(ipg_per, 22M) with the current
clk_divider_bestdiv() implementation will result in the rate change up
to ahb level like the following, because of the unnecessary/incorrect
rate change propagation.
ahb --> ipg --> ipg_per
66M 22M 22M
Fix the problem by trying to see if the requested rate can be achieved
by simply changing the divider value, and in that case return the
divider immediately from function clk_divider_bestdiv() as the best
one, so that all those unnecessary rate change propagation can be saved.
Reported-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Patrik writes:
Two fixes for memory leaks split into Cedarview and Poulsbo versions,
and a fix for properly setting the pipe base when using fbdev. It's on
my todo-list to start unifying the chips since they are very similar,
but until then I'd like to split them up in case there are side-effects
on Cedarview that I cannot currently test.
airled: Verified pull from github matches what I expected.
* 'gma500-fixes' of git://github.com/patjak/drm-gma500:
drm/gma500/cdv: Fix cursor gem obj referencing on cdv
drm/gma500/psb: Fix cursor gem obj referencing on psb
drm/gma500/cdv: Unpin framebuffer on crtc disable
drm/gma500/psb: Unpin framebuffer on crtc disable
drm/gma500: Add fb gtt offset to fb base
GEM CMA PRIME support from Laurent.
* 'drm/next' of git://linuxtv.org/pinchartl/fbdev:
drm: GEM CMA: Add DRM PRIME support
drm: GEM CMA: Split object mapping into GEM mapping and CMA mapping
drm: GEM CMA: Split object creation into object alloc and DMA memory alloc
drm/omap: Use drm_gem_mmap_obj() to implement dma-buf mmap
drm/gem: Split drm_gem_mmap() into object search and object mapping
'mout_mpll' is added the list of parent clocks for 'mout_cpu'.
'mout_mpll' is an alias to the clock 'sclk_mpll'. Hence 'sclk_mpll'
should be added to the list of parent clocks.
This results in an error when cpufreq driver for EXYNOS5250 tries to
set 'mout_mpll' as a parent for 'mout_cpu'.
clk_set_parent: clk sclk_mpll can not be parent of clk mout_cpu
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
cpufreq driver for EXYNOS5250 is not a platform driver, hence we cannot
currently pass the clock names through a device tree node. Instead, we
need to make them available through a global alias.
cpufreq driver for EXYNOS5250 requires four clocks - 'armclk',
'mout_cpu', 'mout_mpll' and 'mout_apll'.
'armclk' has already been defined with an alias, 'mout_cpu', 'mout_mpll'
and 'mout_apll' are now defined with an alias.
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
The structures and strings involved with various pretty-print functions
aren't meant to be modified, so make them all const. The exception is
drm_connector_enum_list which does get modified in drm_connector_init().
While at it move the drm_get_connector_status_name() prototype from
drmP.h to drm_crtc.h where it belongs.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Use drm_get_format_name to print more readable pixel format names
in debug output.
Also unify the debug messages to say "unsupported pixel format",
which better describes what is going on.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Rather than just printing the pixel format as a hex number, decode the
fourcc into human readable form, and also decode the LE vs. BE flag.
Keep printing the raw hex number too in case it contains non-printable
characters.
Some examples what the new drm_get_format_name() produces:
DRM_FORMAT_XRGB8888: "XR24 little-endian (0x34325258)"
DRM_FORMAT_YUYV: "YUYV little-endian (0x56595559)"
DRM_FORMAT_RGB565|DRM_FORMAT_BIG_ENDIAN: "RG16 big-endian (0xb6314752)"
Unprintable characters: "D??? big-endian (0xff7f0244)"
v2: Fix patch author
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This allows importing bo's to own device to work without requiring that the buffer is pinned in GART.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Prevents buffers from being pinned forever.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The usb_serial_port structure had the number field, which was the minor
number for the port, which almost no one really cared about. They
really wanted the number of the port within the device, which you had to
subtract from the minor of the parent usb_serial_device structure. To
clean this up, provide the real minor number of the port, and the number
of the port within the serial device separately, as these numbers might
not be related in the future.
Bonus is that this cleans up a lot of logic in the drivers, and saves
lines overall.
Tested-by: Tobias Winter <tobias@linuxdingsda.de>
Reviewed-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--
drivers/staging/serqt_usb2/serqt_usb2.c | 21 +++--------
drivers/usb/serial/ark3116.c | 2 -
drivers/usb/serial/bus.c | 6 +--
drivers/usb/serial/console.c | 2 -
drivers/usb/serial/cp210x.c | 2 -
drivers/usb/serial/cypress_m8.c | 4 +-
drivers/usb/serial/digi_acceleport.c | 6 ---
drivers/usb/serial/f81232.c | 5 +-
drivers/usb/serial/garmin_gps.c | 6 +--
drivers/usb/serial/io_edgeport.c | 58 ++++++++++++--------------------
drivers/usb/serial/io_ti.c | 21 ++++-------
drivers/usb/serial/keyspan.c | 29 +++++++---------
drivers/usb/serial/metro-usb.c | 4 +-
drivers/usb/serial/mos7720.c | 37 +++++++++-----------
drivers/usb/serial/mos7840.c | 52 +++++++++-------------------
drivers/usb/serial/opticon.c | 2 -
drivers/usb/serial/pl2303.c | 2 -
drivers/usb/serial/quatech2.c | 7 +--
drivers/usb/serial/sierra.c | 2 -
drivers/usb/serial/ti_usb_3410_5052.c | 10 ++---
drivers/usb/serial/usb-serial.c | 7 ++-
drivers/usb/serial/usb_wwan.c | 2 -
drivers/usb/serial/whiteheat.c | 20 +++++------
include/linux/usb/serial.h | 6 ++-
24 files changed, 133 insertions(+), 180 deletions(-)
Complier may generate codes that re-read the tun->numqueues during
tun_select_queue(). This may be a race if vlan->numqueues were changed in the
same time and can lead unexpected result (e.g. very huge value).
We need prevent the compiler from generating such codes by adding an
ACCESS_ONCE() to make sure tun->numqueues were only read once.
Bug were introduced by commit c8d68e6be1
(tuntap: multiqueue support).
Reported-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we decide not use zero-copy, msg.control should be set to NULL otherwise
macvtap/tap may set zerocopy callbacks which may decrease the kref of ubufs
wrongly.
Bug were introduced by commit cedb9bdce0
(vhost-net: skip head management if no outstanding).
This solves the following warnings:
WARNING: at include/linux/kref.h:47 handle_tx+0x477/0x4b0 [vhost_net]()
Modules linked in: vhost_net macvtap macvlan tun nfsd exportfs bridge stp llc openvswitch kvm_amd kvm bnx2 megaraid_sas [last unloaded: tun]
CPU: 5 PID: 8670 Comm: vhost-8668 Not tainted 3.10.0-rc2+ #1566
Hardware name: Dell Inc. PowerEdge R715/00XHKG, BIOS 1.5.2 04/19/2011
ffffffffa0198323 ffff88007c9ebd08 ffffffff81796b73 ffff88007c9ebd48
ffffffff8103d66b 000000007b773e20 ffff8800779f0000 ffff8800779f43f0
ffff8800779f8418 000000000000015c 0000000000000062 ffff88007c9ebd58
Call Trace:
[<ffffffff81796b73>] dump_stack+0x19/0x1e
[<ffffffff8103d66b>] warn_slowpath_common+0x6b/0xa0
[<ffffffff8103d6b5>] warn_slowpath_null+0x15/0x20
[<ffffffffa0197627>] handle_tx+0x477/0x4b0 [vhost_net]
[<ffffffffa0197690>] handle_tx_kick+0x10/0x20 [vhost_net]
[<ffffffffa019541e>] vhost_worker+0xfe/0x1a0 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffffa0195320>] ? vhost_attach_cgroups_work+0x30/0x30 [vhost_net]
[<ffffffff81061f46>] kthread+0xc6/0xd0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
[<ffffffff817a1aec>] ret_from_fork+0x7c/0xb0
[<ffffffff81061e80>] ? kthread_freezable_should_stop+0x70/0x70
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Newer Broadcom BCM63xx SoCs: 6328, 6362 and 6368 have an integrated switch
which needs to be driven slightly differently from the traditional
external switches. This patch introduces changes in arch/mips/bcm63xx in order
to:
- register a bcm63xx_enetsw driver instead of bcm63xx_enet driver
- update DMA channels configuration & state RAM base addresses
- add a new platform data configuration knob to define the number of
ports per switch/device and force link on some ports
- define the required switch registers
On the driver side, the following changes are required:
- the switch ports need to be polled to ensure the link is up and
running and RX/TX can properly work
- basic switch configuration needs to be performed for the switch to
forward packets to the CPU
- update the MIB counters since the integrated
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current bcm63xx_enet driver always uses bcmenet_shared_base whenever
it needs to access DMA channel configuration space or access the DMA
channel state RAM. Split these register in 3 parts to be more accurate:
- global DMA configuration
- per DMA channel configuration space
- per DMA channel state RAM space
This is preliminary to support new chips where the global DMA
configuration remains the same, but there is a varying number of DMA
channels located at a different memory offset.
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement the rset_nway ethtool callback which uses libphy generic
autonegotiation restart function.
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch reworks the UEFI anti-bricking code, including an effective
reversion of cc5a080c and 31ff2f20. It turns out that calling
QueryVariableInfo() from boot services results in some firmware
implementations jumping to physical addresses even after entering virtual
mode, so until we have 1:1 mappings for UEFI runtime space this isn't
going to work so well.
Reverting these gets us back to the situation where we'd refuse to create
variables on some systems because they classify deleted variables as "used"
until the firmware triggers a garbage collection run, which they won't do
until they reach a lower threshold. This results in it being impossible to
install a bootloader, which is unhelpful.
Feedback from Samsung indicates that the firmware doesn't need more than
5KB of storage space for its own purposes, so that seems like a reasonable
threshold. However, there's still no guarantee that a platform will attempt
garbage collection merely because it drops below this threshold. It seems
that this is often only triggered if an attempt to write generates a
genuine EFI_OUT_OF_RESOURCES error. We can force that by attempting to
create a variable larger than the remaining space. This should fail, but if
it somehow succeeds we can then immediately delete it.
I've tested this on the UEFI machines I have available, but I don't have
a Samsung and so can't verify that it avoids the bricking problem.
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Lee, Chun-Y <jlee@suse.com> [ dummy variable cleanup ]
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
TINY_RCU's reset_cpu_stall_ticks() and check_cpu_stalls() functions
are defined unconditionally, and are empty functions if CONFIG_RCU_TRACE
is disabled (which in turns disables detection of RCU CPU stalls).
This commit saves a few lines of source code by defining these functions
only if CONFIG_RCU_TRACE=y.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Now that TINY_PREEMPT_RCU is no more, exit_rcu() is always an empty
function. But if TINY_RCU is going to have an empty function, it should
be in include/linux/rcutiny.h, where it does not bloat the kernel.
This commit therefore moves exit_rcu() out of kernel/rcupdate.c to
kernel/rcutree_plugin.h, and places a static inline empty function in
include/linux/rcutiny.h in order to shrink TINY_RCU a bit.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Because TINY_PREEMPT_RCU is no more, this commit removes its tracing
formats from the documentation.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
This commit rearranges code in order to allow ifdefs to be consolidated
in kernel/rcutiny_plugin.h, simplifying the code.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
With the removal of CONFIG_TINY_PREEMPT_RCU, rcu_preempt_note_context_switch()
is now an empty function. This commit therefore eliminates it by inlining it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Now that CONFIG_TINY_PREEMPT_RCU is no more, this commit removes
the CONFIG_TINY_RCU ifdefs from include/linux/rcutiny.h in favor of
unconditionally compiling the CONFIG_TINY_RCU legs of those ifdefs.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Moved removal of #else to "Remove TINY_PREEMPT_RCU" as
suggested by Josh Triplett. ]
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
With the removal of CONFIG_TINY_PREEMPT_RCU, check_cpu_stall_preempt()
is now an empty function. This commit therefore eliminates it by
inlining it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
TINY_PREEMPT_RCU could use a kthread to handle RCU callback invocation,
which required an API to abstract kthread vs. softirq invocation.
Now that TINY_PREEMPT_RCU is no longer with us, this commit retires
this API in favor of direct use of the relevant softirq primitives.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
With the removal of CONFIG_TINY_PREEMPT_RCU, rcu_preempt_process_callbacks()
is now an empty function. This commit therefore eliminates it by
inlining it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
With the removal of CONFIG_TINY_PREEMPT_RCU, rcu_preempt_remove_callbacks()
is now an empty function. This commit therefore eliminates it by
inlining it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
With the removal of CONFIG_TINY_PREEMPT_RCU, rcu_preempt_check_callbacks()
is now an empty function. This commit therefore eliminates it by
inlining it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
With the removal of CONFIG_TINY_PREEMPT_RCU, show_tiny_preempt_stats()
is now an empty function. This commit therefore eliminates it by
inlining it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
TINY_PREEMPT_RCU adds significant code and complexity, but does not
offer commensurate benefits. People currently using TINY_PREEMPT_RCU
can get much better memory footprint with TINY_RCU, or, if they really
need preemptible RCU, they can use TREE_PREEMPT_RCU with a relatively
minor degradation in memory footprint. Please note that this move
has been widely publicized on LKML (https://lkml.org/lkml/2012/11/12/545)
and on LWN (http://lwn.net/Articles/541037/).
This commit therefore removes TINY_PREEMPT_RCU.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Updated to eliminate #else in rcutiny.h as suggested by Josh ]
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
At the point of up_out label in kvmppc_hv_setup_htab_rma(),
srcu read lock is still held.
We have to release it before return.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: kvm@vger.kernel.org
Cc: kvm-ppc@vger.kernel.org
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
These interfaces never did get used, so this commit removes them,
their rcutorture tests, and documentation referencing them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
The Kconfig help text for the RCU_NOCB_CPU_NONE, RCU_NOCB_CPU_ZERO,
and RCU_NOCB_CPU_ALL Kconfig options was unclear, so this commit
adds a bit more detail.
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Two ifdefs in kernel/rcupdate.c now have identical conditions with
nothing between them, so the commit merges them into a single ifdef.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Systems with HZ=100 can have slow bootup times due to the default
three-jiffy delays between quiescent-state forcing attempts. This
commit therefore auto-tunes the RCU_JIFFIES_TILL_FORCE_QS value based
on the value of HZ. However, this would break very large systems that
require more time between quiescent-state forcing attempts. This
commit therefore also ups the default delay by one jiffy for each
256 CPUs that might be on the system (based off of nr_cpu_ids at
runtime, -not- NR_CPUS at build time).
Updated to collapse #ifdefs for RCU_JIFFIES_TILL_FORCE_QS into a
step-function definition as suggested by Josh Triplett.
Reported-by: Paul Mackerras <paulus@au1.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
