Commit Graph

361182 Commits

Author SHA1 Message Date
Thomas Gleixner d2054b2c11 posix-timers: Remove unused variable
Remove the unused variable *node introduced by commit 5ed67f05 (posix
timers: Allocate timer id per process)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Pavel Emelyanov <xemul@parallels.com>
2013-04-18 12:51:19 +02:00
Stephen Boyd c038c1c441 clockevents: Switch into oneshot mode even if broadcast registered late
tick_oneshot_notify() is used to notify a particular CPU to try
to switch into oneshot mode after a oneshot capable tick device
is registered and tick_clock_notify() is used to notify all CPUs
to try to switch into oneshot mode after a high res clocksource
is registered. There is one caveat; if the tick devices suffer
from FEAT_C3_STOP we don't try to switch into oneshot mode unless
we have a oneshot capable broadcast device already registered.

If the broadcast device is registered after the tick devices that
have FEAT_C3_STOP we'll never try to switch into oneshot mode
again, causing us to be stuck in periodic mode forever. Avoid
this scenario by calling tick_clock_notify() after we register
the broadcast device so that we try to switch into oneshot mode
on all CPUs one more time.

[ tglx: Adopted to timers/core and added a comment ]

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Link: http://lkml.kernel.org/r/1366219566-29783-1-git-send-email-sboyd@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17 21:30:56 +02:00
Nathan Zimmer b3956a896e timer_list: Convert timer list to be a proper seq_file
When running with 4096 cores attemping to read /proc/timer_list will fail
with an ENOMEM condition.  On a sufficantly large systems the total amount
of data is more then 4mb, so it won't fit into a single buffer.  The
failure can also occur on smaller systems when memory fragmentation is
high as reported by Dave Jones.

Convert /proc/timer_list to a proper seq_file with its own iterator.  This
is a little more complex given that we have to make two passes with two
separate headers.

sysrq_timer_list_show also needed to be updated to reflect the fact that
now timer_list_show only does one cpu at at time.

Signed-off-by: Nathan Zimmer <nzimmer@sgi.com>
Reported-by: Dave Jones <davej@redhat.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Link: http://lkml.kernel.org/r/1364345790-14577-3-git-send-email-nzimmer@sgi.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17 20:51:02 +02:00
Nathan Zimmer 60cf7ea849 timer_list: Split timer_list_show_tickdevices
Split timer_list_show_tickdevices() into the header printout and pull
the rest up to timer_list_show. This is a preparatory patch for
converting timer_list to a proper seqfile with its own iterator

Signed-off-by: Nathan Zimmer <nzimmer@sgi.com>
Reported-by: Dave Jones <davej@redhat.com>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Link: http://lkml.kernel.org/r/1364345790-14577-2-git-send-email-nzimmer@sgi.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17 20:51:02 +02:00
Pavel Emelyanov 57b8015e07 posix-timers: Show sigevent info in proc file
Previous patch added proc file to list posix timers created by task.
Expand the information provided in this file by adding info about
notification method, with which timers were created. I.e. after
the "ID:" line there go

1. "signal:" line, that shows signal number and sigval bits;
2. "notify:" line, that shows the timer notification method.

Thus the timer entry would looke like this:

ID: 123
signal: 14/0000000000b005d0
notify: signal/pid.732

This information is enough to understand how timer_create() was called
for each particular timer.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Matthew Helsley <matt.helsley@gmail.com>
Link: http://lkml.kernel.org/r/513DA024.80404@parallels.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17 20:51:01 +02:00
Pavel Emelyanov 48f6a7a511 posix-timers: Introduce /proc/PID/timers file
Currently kernel doesn't provide any API for getting info about what
posix timers are configured by processes. It's implied, that a process
which configured some timers, knows what it did. However, for external
tools it's impossible to get this information. In particular, this is
critical for checkpoint-restore project to have this info.

Introduce a per-pid proc file with information about posix
timers. Since these timers are shared between threads, this file is
present on tgid level only, no such thing in tid subdirs.

The file format is expected to be the "/proc/<pid>/smaps"-like,
i.e. each timer will occupy seveal lines to allow for future
extending.

Each new timer entry starts with the

ID: <number>

line which is added by this patch.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Matthew Helsley <matt.helsley@gmail.com>
Link: http://lkml.kernel.org/r/513DA00D.6070009@parallels.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17 20:51:01 +02:00
Pavel Emelyanov 5ed67f05f6 posix timers: Allocate timer id per process (v2)
Currently kernel generates IDs for posix timers in a global manner --
there's a kernel-wide IDR tree from which IDs are created. This makes
it impossible to recreate a timer with a desired ID (in particular
this is done by the CRIU checkpoint-restore project) -- since these
IDs are global it may happen, that at the time we recreate a timer, the
ID we want for it is already busy by some other timer.

In order to address this, replace the IDR tree with a global hash
table for timers and makes timer IDs unique per signal_struct (to
which timers are linked anyway). With this, two timers belonging to
different processes may have equal IDs and we can recreate either of
them with the ID we want.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Matthew Helsley <matt.helsley@gmail.com>
Link: http://lkml.kernel.org/r/513D9FF5.9010004@parallels.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17 20:51:01 +02:00
John Stultz 4e8f8b34b9 timekeeping: Make sure to notify hrtimers when TAI offset changes
Now that we have CLOCK_TAI timers, make sure we notify hrtimer
code when TAI offset is changed.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/1365622909-953-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-11 10:19:44 +02:00
David Engraf 51fd36f3fa hrtimer: Fix ktime_add_ns() overflow on 32bit architectures
One can trigger an overflow when using ktime_add_ns() on a 32bit
architecture not supporting CONFIG_KTIME_SCALAR.

When passing a very high value for u64 nsec, e.g. 7881299347898368000
the do_div() function converts this value to seconds (7881299347) which
is still to high to pass to the ktime_set() function as long. The result
in is a negative value.

The problem on my system occurs in the tick-sched.c,
tick_nohz_stop_sched_tick() when time_delta is set to
timekeeping_max_deferment(). The check for time_delta < KTIME_MAX is
valid, thus ktime_add_ns() is called with a too large value resulting in
a negative expire value. This leads to an endless loop in the ticker code:

time_delta: 7881299347898368000
expires = ktime_add_ns(last_update, time_delta)
expires: negative value

This fix caps the value to KTIME_MAX.

This error doesn't occurs on 64bit or architectures supporting
CONFIG_KTIME_SCALAR (e.g. ARM, x86-32).

Cc: stable@vger.kernel.org
Signed-off-by: David Engraf <david.engraf@sysgo.com>
[jstultz: Minor tweaks to commit message & header]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-08 13:21:20 -07:00
Prarit Bhargava 8f294b5a13 hrtimer: Add expiry time overflow check in hrtimer_interrupt
The settimeofday01 test in the LTP testsuite effectively does

        gettimeofday(current time);
        settimeofday(Jan 1, 1970 + 100 seconds);
        settimeofday(current time);

This test causes a stack trace to be displayed on the console during the
setting of timeofday to Jan 1, 1970 + 100 seconds:

[  131.066751] ------------[ cut here ]------------
[  131.096448] WARNING: at kernel/time/clockevents.c:209 clockevents_program_event+0x135/0x140()
[  131.104935] Hardware name: Dinar
[  131.108150] Modules linked in: sg nfsv3 nfs_acl nfsv4 auth_rpcgss nfs dns_resolver fscache lockd sunrpc nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6table_mangle ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 iptable_nat nf_nat_ipv4 nf_nat iptable_mangle ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter ip_tables kvm_amd kvm sp5100_tco bnx2 i2c_piix4 crc32c_intel k10temp fam15h_power ghash_clmulni_intel amd64_edac_mod pcspkr serio_raw edac_mce_amd edac_core microcode xfs libcrc32c sr_mod sd_mod cdrom ata_generic crc_t10dif pata_acpi radeon i2c_algo_bit drm_kms_helper ttm drm ahci pata_atiixp libahci libata usb_storage i2c_core dm_mirror dm_region_hash dm_log dm_mod
[  131.176784] Pid: 0, comm: swapper/28 Not tainted 3.8.0+ #6
[  131.182248] Call Trace:
[  131.184684]  <IRQ>  [<ffffffff810612af>] warn_slowpath_common+0x7f/0xc0
[  131.191312]  [<ffffffff8106130a>] warn_slowpath_null+0x1a/0x20
[  131.197131]  [<ffffffff810b9fd5>] clockevents_program_event+0x135/0x140
[  131.203721]  [<ffffffff810bb584>] tick_program_event+0x24/0x30
[  131.209534]  [<ffffffff81089ab1>] hrtimer_interrupt+0x131/0x230
[  131.215437]  [<ffffffff814b9600>] ? cpufreq_p4_target+0x130/0x130
[  131.221509]  [<ffffffff81619119>] smp_apic_timer_interrupt+0x69/0x99
[  131.227839]  [<ffffffff8161805d>] apic_timer_interrupt+0x6d/0x80
[  131.233816]  <EOI>  [<ffffffff81099745>] ? sched_clock_cpu+0xc5/0x120
[  131.240267]  [<ffffffff814b9ff0>] ? cpuidle_wrap_enter+0x50/0xa0
[  131.246252]  [<ffffffff814b9fe9>] ? cpuidle_wrap_enter+0x49/0xa0
[  131.252238]  [<ffffffff814ba050>] cpuidle_enter_tk+0x10/0x20
[  131.257877]  [<ffffffff814b9c89>] cpuidle_idle_call+0xa9/0x260
[  131.263692]  [<ffffffff8101c42f>] cpu_idle+0xaf/0x120
[  131.268727]  [<ffffffff815f8971>] start_secondary+0x255/0x257
[  131.274449] ---[ end trace 1151a50552231615 ]---

When we change the system time to a low value like this, the value of
timekeeper->offs_real will be a negative value.

It seems that the WARN occurs because an hrtimer has been started in the time
between the releasing of the timekeeper lock and the IPI call (via a call to
on_each_cpu) in clock_was_set() in the do_settimeofday() code.  The end result
is that a REALTIME_CLOCK timer has been added with softexpires = expires =
KTIME_MAX.  The hrtimer_interrupt() fires/is called and the loop at
kernel/hrtimer.c:1289 is executed.  In this loop the code subtracts the
clock base's offset (which was set to timekeeper->offs_real in
do_settimeofday()) from the current hrtimer_cpu_base->expiry value (which
was KTIME_MAX):

	KTIME_MAX - (a negative value) = overflow

A simple check for an overflow can resolve this problem.  Using KTIME_MAX
instead of the overflow value will result in the hrtimer function being run,
and the reprogramming of the timer after that.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
[jstultz: Tweaked commit subject]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-08 13:20:44 -07:00
Thomas Gleixner ca4523cda4 timekeeping: Shorten seq_count region
Shorten the seqcount write hold region to the actual update of the
timekeeper and the related data (e.g vsyscall).

On a contemporary x86 system this reduces the maximum latencies on
Preempt-RT from 8us to 4us on the non-timekeeping cores.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:32 -07:00
Thomas Gleixner 48cdc135d4 timekeeping: Implement a shadow timekeeper
Use the shadow timekeeper to do the update_wall_time() adjustments and
then copy it over to the real timekeeper.

Keep the shadow timekeeper in sync when updating stuff outside of
update_wall_time().

This allows us to limit the timekeeper_seq hold time to the update of
the real timekeeper and the vsyscall data in the next patch.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:32 -07:00
Thomas Gleixner 7ec98e15aa timekeeping: Delay update of clock->cycle_last
For calculating the new timekeeper values store the new cycle_last
value in the timekeeper and update the clock->cycle_last just when we
actually update the new values.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:31 -07:00
Thomas Gleixner 14a3b6abe9 timekeeping: Store cycle_last value in timekeeper struct as well
For implementing a shadow timekeeper and a split calculation/update
region we need to store the cycle_last value in the timekeeper and
update the value in the clocksource struct only in the update region.

Add the extra storage to the timekeeper.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:31 -07:00
John Stultz a076b2146f ntp: Remove ntp_lock, using the timekeeping locks to protect ntp state
In order to properly handle the NTP state in future changes to the
timekeeping lock management, this patch moves the management of
all of the ntp state under the timekeeping locks.

This allows us to remove the ntp_lock.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:17 -07:00
John Stultz 0b5154fb90 timekeeping: Simplify tai updating from do_adjtimex
Since we are taking the timekeeping locks, just go ahead
and update any tai change directly, rather then dropping
the lock and calling a function that will just take it again.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:16 -07:00
John Stultz 06c017fdd4 timekeeping: Hold timekeepering locks in do_adjtimex and hardpps
In moving the NTP state to be protected by the timekeeping locks,
be sure to acquire the timekeeping locks prior to calling
ntp functions.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:16 -07:00
John Stultz cef90377fa timekeeping: Move ADJ_SETOFFSET to top level do_adjtimex()
Since ADJ_SETOFFSET adjusts the timekeeping state, process
it as part of the top level do_adjtimex() function in
timekeeping.c.

This avoids deadlocks that could occur once we change the
ntp locking rules.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:15 -07:00
John Stultz 87ace39b71 ntp: Rework do_adjtimex to take timespec and tai arguments
In order to change the locking rules, we need to provide
the timespec and tai values rather then having the ntp
logic acquire these values itself.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:15 -07:00
John Stultz e4085693f6 ntp: Move timex validation to timekeeping do_adjtimex call.
Move logic that does not need the ntp state to be done
in the timekeeping do_adjtimex() call.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:14 -07:00
John Stultz aa6f9c595d ntp: Move do_adjtimex() and hardpps() functions to timekeeping.c
In preparation for changing the ntp locking rules, move
do_adjtimex and hardpps accessor functions to timekeeping.c,
but keep the code logic in ntp.c.

This patch also introduces a ntp_internal.h file so timekeeping
specific interfaces of ntp.c can be more limitedly shared with
timekeeping.c.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:14 -07:00
John Stultz ad460967a2 ntp: Split out timex validation from do_adjtimex
Split out the timex validation done in do_adjtimex into a separate
function. This will help simplify logic in following patches.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-04-04 13:18:14 -07:00
Thomas Gleixner 0ed2aef9b3 Merge branch 'fortglx/3.10/time' of git://git.linaro.org/people/jstultz/linux into timers/core 2013-04-03 12:27:29 +02:00
Christian Daudt 8011657b9e ARM: bcm281xx: Add timer driver (driver portion)
This adds support for the Broadcom timer, used in the following SoCs:
BCM11130, BCM11140, BCM11351, BCM28145, BCM28155

Updates from V6:
- Split DT portion into a separate patch

Updates from V5:
- Rebase to latest arm-soc/for-next

Updates from V4:
- Switch code to use CLOCKSOURCE_OF_DECLARE

Updates from V3:
- Migrate to 3.9 timer framework updates

Updates from V2:
- prepend static fns + fields with kona_

Updates from V1:
- Rename bcm_timer.c to bcm_kona_timer.c
- Pull .h into bcm_kona_timer.c
- Make timers static
- Clean up comment block
- Switched to using clockevents_config_and_register
- Added an error to the get_timer loop if it repeats too much
- Added to Documentation/devicetree/bindings/arm/bcm/bcm,kona-timer.txt
- Added missing readl to timer_disable_and_clear

Note: bcm,kona-timer was kept as the 'compatible' field to make it
specific enough for when there are multiple bcm timers (bcm,timer is
too generic).

Signed-off-by: Christian Daudt <csd@broadcom.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-28 10:58:55 -07:00
Fengguang Wu dd5d70e869 timekeeping: __timekeeping_set_tai_offset can be static
Yet again, the kbuild test robot saves the day, noting
I left out defining __timekeeping_set_tai_offset as
static. It even sent me this patch.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-25 12:24:24 -07:00
Rado Vrbovsky cfea7d7e45 tick: Change log level of NOHZ: local_softirq_pending message
The "NOHZ: local_softirq_pending" message is a largely informational
message.  This makes extra work for customers that have a policy of
investigating all kernel log messages logged at <= KERN_ERR log level.
This patch sets the message to a different log level.

[ tglx: Use pr_warn() ]

Signed-off-by: Rado Vrbovsky <rvrbovsk@redhat.com>
Cc: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/2037057938.893524.1360345050772.JavaMail.root@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-25 10:46:59 +01:00
David Daney 8ffbc7d9ff hrtimer/trivial: Fix comment text in hrtimer.c
The comments mention HRTIMER_ABS and HRTIMER_REL, these symbols don't
exist, the proper names are HRTIMER_MODE_ABS and HRTIMER_MODE_REL.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: Jiri Kosina <trivial@kernel.org>
Link: http://lkml.kernel.org/r/1363202438-21234-1-git-send-email-ddaney.cavm@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-25 10:46:59 +01:00
Thomas Gleixner 9a7a71b1d0 timekeeping: Split timekeeper_lock into lock and seqcount
We want to shorten the seqcount write hold time. So split the seqlock
into a lock and a seqcount.

Open code the seqwrite_lock in the places which matter and drop the
sequence counter update where it's pointless.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[jstultz: Merge fixups from CLOCK_TAI collisions]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-22 16:20:01 -07:00
Thomas Gleixner 7e40672d93 timekeeping: Move lock out of timekeeper struct
Make the lock a separate entity. Preparatory patch for shadow
timekeeper structure.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[Merged with CLOCK_TAI changes]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-22 16:20:00 -07:00
Thomas Gleixner eb93e4d930 timekeeping: Make jiffies_lock internal
Nothing outside of the timekeeping core needs that lock.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-22 16:20:00 -07:00
Thomas Gleixner 23a9537a69 timekeeping: Calc stuff once
Calculate the cycle interval shifted value once. No functional change,
just makes the code more readable.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-22 16:19:59 -07:00
John Stultz 90adda98b8 hrtimer: Add hrtimer support for CLOCK_TAI
Add hrtimer support for CLOCK_TAI, as well as posix timer interfaces.

Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-22 16:19:59 -07:00
John Stultz 1ff3c9677b timekeeping: Add CLOCK_TAI clockid
This add a CLOCK_TAI clockid and the needed accessors.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-22 16:19:59 -07:00
John Stultz cc244ddae6 timekeeping: Move TAI managment into timekeeping core from ntp
Currently NTP manages the TAI offset. Since there's plans for a
CLOCK_TAI clockid, push the TAI management into the timekeeping
core.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-22 16:19:58 -07:00
Thomas Gleixner 19919226c3 clockevents: Add missing tick_check_broadcast_expired() for CLOCKEVENTS=n
Fengs build robot reports:

arch/arm/kernel/process.c: In function 'cpu_idle':
arch/arm/kernel/process.c:211:4: error: implicit declaration of function
'tick_check_broadcast_expired' [-Werror=implicit-function-declaration]

Add the missing inline function for non clockevent builds

Reported-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-22 10:48:33 +01:00
Feng Tang e445cf1c42 timekeeping: utilize the suspend-nonstop clocksource to count suspended time
There are some new processors whose TSC clocksource won't stop during
suspend. Currently, after system resumes, kernel will use persistent
clock or RTC to compensate the sleep time, but with these nonstop
clocksources, we could skip the special compensation from external
sources, and just use current clocksource for time recounting.

This can solve some time drift bugs caused by some not-so-accurate or
error-prone RTC devices.

The current way to count suspended time is first try to use the persistent
clock, and then try the RTC if persistent clock can't be used. This
patch will change the trying order to:
	suspend-nonstop clocksource -> persistent clock -> RTC

When counting the sleep time with nonstop clocksource, use an accurate way
suggested by Jason Gunthorpe to cover very large delta cycles.

Signed-off-by: Feng Tang <feng.tang@intel.com>
[jstultz: Small optimization, avoiding re-reading the clocksource]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-15 16:51:29 -07:00
Feng Tang 82f9c080b2 x86: tsc: Add support for new S3_NONSTOP feature
Add support for new S3_NONSTOP feature

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-15 16:51:18 -07:00
Feng Tang 5caf463625 clocksource: Add new feature flag CLOCK_SOURCE_SUSPEND_NONSTOP
Some x86 processors have a TSC clocksource, which continues to run
even when system is suspended. Also most OMAP platforms have a
32 KHz timer which has similar capability. Add a feature flag so that
it could be utilized.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-15 16:50:27 -07:00
Feng Tang c54fdbb282 x86: Add cpu capability flag X86_FEATURE_NONSTOP_TSC_S3
On some new Intel Atom processors (Penwell and Cloverview), there is
a feature that the TSC won't stop in S3 state, say the TSC value
won't be reset to 0 after resume. This feature makes TSC a more reliable
clocksource and could benefit the timekeeping code during system
suspend/resume cycle, so add a flag for it.

Signed-off-by: Feng Tang <feng.tang@intel.com>
[jstultz: Fix checkpatch warning]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-15 16:50:26 -07:00
Prarit Bhargava 3195ef59cb x86: Do full rtc synchronization with ntp
Every 11 minutes ntp attempts to update the x86 rtc with the current
system time.  Currently, the x86 code only updates the rtc if the system
time is within +/-15 minutes of the current value of the rtc. This
was done originally to avoid setting the RTC if the RTC was in localtime
mode (common with Windows dualbooting).  Other architectures do a full
synchronization and now that we have better infrastructure to detect
when the RTC is in localtime, there is no reason that x86 should be
software limited to a 30 minute window.

This patch changes the behavior of the kernel to do a full synchronization
(year, month, day, hour, minute, and second) of the rtc when ntp requests
a synchronization between the system time and the rtc.

I've used the RTC library functions in this patchset as they do all the
required bounds checking.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: x86@kernel.org
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: linux-efi@vger.kernel.org
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
[jstultz: Tweak commit message, fold in build fix found by fengguang
Also add select RTC_LIB to X86, per new dependency, as found by prarit]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-15 16:50:26 -07:00
John Stultz 7859e404ae timekeeping: Use inject_offset in warp_clock
When warping the clock (from a local time RTC), use
timekeeping_inject_offset() to atomically add the offset.

This avoids any minor time error caused by the delay between
reading the time, and then setting the adjusted time.

Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-15 16:50:20 -07:00
Dong Zhu c30bd09915 timekeeping: Avoid adjust kernel time once hwclock kept in UTC time
If the Hardware Clock kept in local time,kernel will adjust the time
to be UTC time.But if Hardware Clock kept in UTC time,system will make
a dummy settimeofday call first (sys_tz.tz_minuteswest = 0) to make sure
the time is not shifted,so at this point I think maybe it is not necessary
to set the kernel time once the sys_tz.tz_minuteswest is zero.

Signed-off-by: Dong Zhu <bluezhudong@gmail.com>
[jstultz: Updated to merge with conflicting changes ]
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-03-15 16:50:12 -07:00
Thomas Gleixner 35b61edb41 x86: Use tick broadcast expired check
Avoid going back into deep idle if the tick broadcast IPI is about to
fire.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20130306111537.702278273@linutronix.de
2013-03-13 11:39:40 +01:00
Thomas Gleixner 80bbe9f273 arm: Use tick broadcast expired check
Avoid going back into deep idle if the tick broadcast IPI is about to
fire.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Jason Liu <liu.h.jason@gmail.com>
Link: http://lkml.kernel.org/r/20130306111537.640722922@linutronix.de
2013-03-13 11:39:40 +01:00
Thomas Gleixner eaa907c546 tick: Provide a check for a forced broadcast pending
On the CPU which gets woken along with the target CPU of the broadcast
the following happens:

  deep_idle()
			<-- spurious wakeup
  broadcast_exit()
    set forced bit
  
  enable interrupts
    
			<-- Nothing happens

  disable interrupts

  broadcast_enter()
			<-- Here we observe the forced bit is set
  deep_idle()

Now after that the target CPU of the broadcast runs the broadcast
handler and finds the other CPU in both the broadcast and the forced
mask, sends the IPI and stuff gets back to normal.

So it's not actually harmful, just more evidence for the theory, that
hardware designers have access to very special drug supplies.

Now there is no point in going back to deep idle just to wake up again
right away via an IPI. Provide a check which allows the idle code to
avoid the deep idle transition.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Jason Liu <liu.h.jason@gmail.com>
Link: http://lkml.kernel.org/r/20130306111537.565418308@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-13 11:39:39 +01:00
Thomas Gleixner 989dcb645c tick: Handle broadcast wakeup of multiple cpus
Some brilliant hardware implementations wake multiple cores when the
broadcast timer fires. This leads to the following interesting
problem:

CPU0				CPU1
wakeup from idle		wakeup from idle

leave broadcast mode		leave broadcast mode
 restart per cpu timer		 restart per cpu timer
 	     	 		go back to idle
handle broadcast
 (empty mask)			
				enter broadcast mode
				programm broadcast device
enter broadcast mode
programm broadcast device

So what happens is that due to the forced reprogramming of the cpu
local timer, we need to set a event in the future. Now if we manage to
go back to idle before the timer fires, we switch off the timer and
arm the broadcast device with an already expired time (covered by
forced mode). So in the worst case we repeat the above ping pong
forever.
					
Unfortunately we have no information about what caused the wakeup, but
we can check current time against the expiry time of the local cpu. If
the local event is already in the past, we know that the broadcast
timer is about to fire and send an IPI. So we mark ourself as an IPI
target even if we left broadcast mode and avoid the reprogramming of
the local cpu timer.

This still leaves the possibility that a CPU which is not handling the
broadcast interrupt is going to reach idle again before the IPI
arrives. This can't be solved in the core code and will be handled in
follow up patches.

Reported-by: Jason Liu <liu.h.jason@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Link: http://lkml.kernel.org/r/20130306111537.492045206@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-13 11:39:39 +01:00
Thomas Gleixner 26517f3e99 tick: Avoid programming the local cpu timer if broadcast pending
If the local cpu timer stops in deep idle, we arm the broadcast device
and get woken by an IPI. Now when we return from deep idle we reenable
the local cpu timer unconditionally before handling the IPI. But
that's a pointless exercise: the timer is already expired and the IPI
is on the way. And it's an expensive exercise as we use the forced
reprogramming mode so that we do not lose a timer event. This forced
reprogramming will loop at least once in the retry.

To avoid this reprogramming, we mark the cpu in a pending bit mask
before we send the IPI. Now when the IPI target cpu wakes up, it will
see the pending bit set and skip the reprogramming. The reprogramming
of the cpu local timer will happen in the IPI handler which runs the
cpu local timer interrupt function.

Reported-by: Jason Liu <liu.h.jason@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: LAK <linux-arm-kernel@lists.infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Arjan van de Veen <arjan@infradead.org>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Link: http://lkml.kernel.org/r/20130306111537.431082074@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-13 11:39:39 +01:00
Thomas Gleixner f7dce82d53 Merge commit 'v3.9-rc2' into timers/core
Fold in upstream fixes.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-13 11:39:07 +01:00
Linus Torvalds 7c6baa304b Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc minor fixes mostly related to tracing"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  s390: Fix a header dependencies related build error
  tracing: update documentation of snapshot utility
  tracing: Do not return EINVAL in snapshot when not allocated
  tracing: Add help of snapshot feature when snapshot is empty
  ftrace: Update the kconfig for DYNAMIC_FTRACE
2013-03-11 07:54:29 -07:00
Linus Torvalds 0cb7750825 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Missing cancel of work items in mac80211 MLME, from Ben Greear.

 2) Fix DMA mapping handling in iwlwifi by using coherent DMA for
    command headers, from Johannes Berg.

 3) Decrease the amount of pressure on the page allocator by using order
    1 pages less in iwlwifi, from Emmanuel Grumbach.

 4) Fix mesh PS broadcast OOPS in mac80211, from Marco Porsch.

 5) Don't forget to recalculate idle state in mac80211 monitor
    interface, from Felix Fietkau.

 6) Fix varargs in netfilter conntrack handler, from Joe Perches.

 7) Need to reset entire chip when command queue fills up in iwlwifi,
    from Emmanuel Grumbach.

 8) The TX antenna value must be valid when calibrations are performed
    in iwlwifi, fix from Dor Shaish.

 9) Don't generate netfilter audit log entries when audit is disabled,
    from Gao Feng.

10) Deal with DMA unit hang on e1000e during power state transitions,
    from Bruce Allan.

11) Remove BUILD_BUG_ON check from igb driver, from Alexander Duyck.

12) Fix lockdep warning on i2c handling of igb driver, from Carolyn
    Wyborny.

13) Fix several TTY handling issues in IRDA ircomm tty driver, from
    Peter Hurley.

14) Several QFQ packet scheduler fixes from Paolo Valente.

15) When VXLAN encapsulates on transmit, we have to reset the netfilter
    state.  From Zang MingJie.

16) Fix jiffie check in net_rx_action() so that we really cap the
    processing at 2HZ.  From Eric Dumazet.

17) Fix erroneous trigger of IP option space exhaustion, when routers
    are pre-specified and we are looking to see if we can insert a
    timestamp, we will have the space.  From David Ward.

18) Fix various issues in benet driver wrt waiting for firmware to
    finish POST after resets or errors.  From Gavin Shan and Sathya
    Perla.

19) Fix TX locking in SFC driver, from Ben Hutchings.

20) Like the VXLAN fix above, when we encap in a TUN device we have to
    reset the netfilter state.  This should fix several strange crashes
    reported by Dave Jones and others.  From Eric Dumazet.

21) Don't forget to clean up MAC address resources when shutting down a
    port in mlx4 driver, from Yan Burman.

22) Fix divide by zero in vmxnet3 driver, from Bhavesh Davda.

23) Fix device statistic regression in tg3 when the driver is using
    phylib, from Nithin Sujir.

24) Fix info leak in several netlink handlers, from Mathias Krause.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (79 commits)
  6lowpan: Fix endianness issue in is_addr_link_local().
  rrunner.c: fix possible memory leak in rr_init_one()
  dcbnl: fix various netlink info leaks
  rtnl: fix info leak on RTM_GETLINK request for VF devices
  bridge: fix mdb info leaks
  tg3: Update link_up flag for phylib devices
  ipv6: stop multicast forwarding to process interface scoped addresses
  bridging: fix rx_handlers return code
  netlabel: fix build problems when CONFIG_IPV6=n
  drivers/isdn: checkng length to be sure not memory overflow
  net/rds: zero last byte for strncpy
  bnx2x: Fix SFP+ misconfiguration in iSCSI boot scenario
  bnx2x: Fix intermittent long KR2 link up time
  macvlan: Set IFF_UNICAST_FLT flag to prevent unnecessary promisc mode.
  team: unsyc the devices addresses when port is removed
  bridge: add missing vid to br_mdb_get()
  Fix: sparse warning in inet_csk_prepare_forced_close
  afkey: fix a typo
  MAINTAINERS: Update qlcnic maintainers list
  netlabel: correctly list all the static label mappings
  ...
2013-03-11 07:51:59 -07:00