Ashwin Chaugule [Fri, 15 Apr 2016 00:45:53 +0000 (20:45 -0400)] 
cpufreq: ACPI / CPPC: Add module support for cppc_cpufreq driver
Add a function to cleanup at module exit and export
appropriate GPL string to enable moduler support
for the cppc_cpufreq driver.
Reported-by: Srinivas Pandruvada <srinivas.pandruvada@intel.com>
Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Philippe Longepe [Fri, 22 Apr 2016 18:46:09 +0000 (11:46 -0700)] 
cpufreq: intel_pstate: Use average P-State instead of current P-State
The result returned by pid_calc() is subtracted from current_pstate
(which is the P-State requested during the last period) in order to
obtain the target P-State for the current iteration.
However, current_pstate may not reflect the real current P-State of
the CPU. In particular, that P-State may be higher because of the
frequency sharing per module.
The theory is:
- The load is the percentage of time spent in C0 and is related to
the average P-State during the same period.
- The last requested P-State can be completely different than the
average P-State (because of frequency sharing or throttling).
- The P-State shift computed by the pid_calc is based on the load
computed at average P-State, so the shift must be relative to
this average P-State.
Using the average P-State instead of current P-State improves power
without significant performance penalty in cases when a task migrates
from one core to other core sharing frequency and voltage.
Performance and power comparison with this patch on Cherry Trail
platform using Android:
Benchmark ?Perf ?Power
FishTank 10.45% 3.1%
SmartBench-Gaming -0.1% -10.4%
SmartBench-Productivity -0.8% -10.4%
CandyCrush n/a -17.4%
AngryBirds n/a -5.9%
videoPlayback n/a -13.9%
audioPlayback n/a -4.9%
IcyRocks-20-50 0.0% -38.4%
iozone RR -0.16% -1.3%
iozone RW 0.74% -1.3%
Signed-off-by: Philippe Longepe <philippe.longepe@linux.intel.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki [Mon, 25 Apr 2016 13:44:01 +0000 (15:44 +0200)] 
Merge back cpufreq changes for v4.7.
Rafael J. Wysocki [Thu, 21 Apr 2016 18:57:47 +0000 (20:57 +0200)]
Revert "cpufreq: governor: Fix negative idle_time when configured with CONFIG_HZ_PERIODIC"
Revert commit
0df35026c6a5 (cpufreq: governor: Fix negative idle_time
when configured with CONFIG_HZ_PERIODIC) that introduced a regression
by causing the ondemand cpufreq governor to misbehave for
CONFIG_TICK_CPU_ACCOUNTING unset (the frequency goes up to the max at
one point and stays there indefinitely).
The revert takes subsequent modifications of the code in question into
account.
Fixes: 0df35026c6a5 (cpufreq: governor: Fix negative idle_time when configured with CONFIG_HZ_PERIODIC)
Link: https://bugzilla.kernel.org/show_bug.cgi?id=115261
Reported-and-tested-by: Timo Valtoaho <timo.valtoaho@gmail.com>
Cc: 4.5+ <stable@vger.kernel.org> # 4.5+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Sun, 10 Apr 2016 03:59:33 +0000 (05:59 +0200)]
cpufreq: Abort cpufreq_update_current_freq() for cpufreq_suspended set
Since governor operations are generally skipped if cpufreq_suspended
is set, cpufreq_start_governor() should do nothing in that case.
That function is called in the cpufreq_online() path, and may also
be called from cpufreq_offline() in some cases, which are invoked
by the nonboot CPUs disabing/enabling code during system suspend
to RAM and resume. That happens when all devices have been
suspended, so if the cpufreq driver relies on things like I2C to
get the current frequency, it may not be ready to do that then.
To prevent problems from happening for this reason, make
cpufreq_update_current_freq(), which is the only function invoked
by cpufreq_start_governor() that doesn't check cpufreq_suspended
already, return 0 upfront if cpufreq_suspended is set.
Fixes: 3bbf8fe3ae08 (cpufreq: Always update current frequency before startig governor)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Sun, 10 Apr 2016 03:59:10 +0000 (05:59 +0200)]
intel_pstate: Avoid getting stuck in high P-states when idle
Jörg Otte reports that commit
a4675fbc4a7a (cpufreq: intel_pstate:
Replace timers with utilization update callbacks) caused the CPUs in
his Haswell-based system to stay in the very high frequency region
even if the system is completely idle.
That turns out to be an existing problem in the intel_pstate driver's
P-state selection algorithm for Core processors. Namely, all
decisions made by that algorithm are based on the average frequency
of the CPU between sampling events and on the P-state requested on
the last invocation, so it may get stuck at a very hight frequency
even if the utilization of the CPU is very low (in fact, it may get
stuck in a inadequate P-state regardless of the CPU utilization).
The only way to kick it out of that limbo is a sufficiently long idle
period (3 times longer than the prescribed sampling interval), but if
that doesn't happen often enough (eg. due to a timing change like
after the above commit), the P-state of the CPU may be inadequate
pretty much all the time.
To address the most egregious manifestations of that issue, reset the
core_busy value used to determine the next P-state to request if the
utilization of the CPU, determined with the help of the MPERF
feedback register and the TSC, is below 1%.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=115771
Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar [Thu, 7 Apr 2016 08:36:57 +0000 (14:06 +0530)] 
cpufreq: ACPI: Remove freq_table from acpi_cpufreq_data
The freq-table is stored in struct cpufreq_policy also and there is
absolutely no need of keeping a copy of its reference in struct
acpi_cpufreq_data. Drop it.
Also policy->freq_table can't be NULL in the target() callback, remove
the useless check as well.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Rebase ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar [Thu, 7 Apr 2016 08:36:58 +0000 (14:06 +0530)]
cpufreq: ACPI: policy->driver_data can't be NULL in ->exit()
Its always set by ->init() and so it will always be there in ->exit().
There is no need to have a special check for just that.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Rebase ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki [Thu, 7 Apr 2016 01:31:57 +0000 (03:31 +0200)]
cpufreq: Rearrange cpufreq_add_dev()
Reorganize the code in cpufreq_add_dev() to avoid using the ret
variable and reduce the indentation level in it.
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Thu, 7 Apr 2016 01:30:40 +0000 (03:30 +0200)]
cpufreq: Simplify switch () in cpufreq_cpu_callback()
Merge two switch entries that do the same thing in
cpufreq_cpu_callback().
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Joe Perches [Tue, 5 Apr 2016 20:28:25 +0000 (13:28 -0700)] 
cpufreq: Use consistent prefixing via pr_fmt
Use the more common kernel style adding a define for pr_fmt.
Miscellanea:
o Remove now unused PFX defines
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Joe Perches [Tue, 5 Apr 2016 20:28:24 +0000 (13:28 -0700)]
cpufreq: Convert printk(KERN_<LEVEL> to pr_<level>
Use the more common logging style.
Miscellanea:
o Coalesce formats
o Realign arguments
o Add a missing space between a coalesced format
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Joe Perches [Tue, 5 Apr 2016 20:28:23 +0000 (13:28 -0700)]
intel_pstate: Use pr_fmt
Prefix the output using the more common kernel style.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Rebase ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Geliang Tang [Tue, 5 Apr 2016 02:38:06 +0000 (10:38 +0800)] 
cpufreq: mt8173: use list_for_each_entry*()
Use list_for_each_entry*() instead of list_for_each*() to simplify
the code.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki [Fri, 8 Apr 2016 23:25:58 +0000 (01:25 +0200)]
intel_pstate: Avoid pointless FRAC_BITS shifts under div_fp()
There are multiple places in intel_pstate where int_tofp() is applied
to both arguments of div_fp(), but this is pointless, because int_tofp()
simply shifts its argument to the left by FRAC_BITS which mathematically
is equivalent to multuplication by 2^FRAC_BITS, so if this is done
to both arguments of a division, the extra factors will cancel each
other during that operation anyway.
Drop the pointless int_tofp() applied to div_fp() arguments throughout
the driver.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar [Wed, 30 Mar 2016 08:15:28 +0000 (13:45 +0530)]
cpufreq: exynos: Use generic platdev driver
The cpufreq-dt-platdev driver supports creation of cpufreq-dt platform
device now, reuse that and remove similar code from platform code.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar [Wed, 30 Mar 2016 08:15:27 +0000 (13:45 +0530)]
ARM: exynos: exynos-cpufreq platform device isn't supported anymore
The driver is removed long back and we don't support this device
anymore. Stop adding it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar [Wed, 30 Mar 2016 08:15:26 +0000 (13:45 +0530)]
cpufreq: dt: Add generic platform-device creation support
Multiple platforms are using the generic cpufreq-dt driver now, and all
of them are required to create a platform device with name "cpufreq-dt",
in order to get the cpufreq-dt probed.
Many of them do it from platform code, others have special drivers just
to do that.
It would be more sensible to do this at a generic place, where all such
platform can mark their entries.
This patch adds a separate file to get this device created. Currently
the compat list of platforms that we support is empty, and will be
filled in as and when we move platforms to use it.
It always compiles as part of the kernel and so doesn't need a
module-exit operation.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar [Wed, 30 Mar 2016 08:15:25 +0000 (13:45 +0530)]
cpufreq: dt: Include types.h from cpufreq-dt.h
cpufreq-dt.h uses 'bool' data type but doesn't include types.h. It works
fine for now as the files that include cpufreq-dt.h, also include
types.h directly or indirectly.
But, when a file includes cpufreq-dt.h without including types.h, we get
a build error. Avoid such errors by including types.h in cpufreq-dt
itself.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Viresh Kumar [Tue, 29 Mar 2016 14:05:12 +0000 (19:35 +0530)]
cpufreq: tegra124: No need of setting platform-data
All CPUs on Tegra platform share clock/voltage lines and there is
absolutely no need of setting platform data for 'cpufreq-dt' platform
device, as that's the default case.
Stop setting platform data for cpufreq-dt device.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Paul Gortmaker [Sun, 27 Mar 2016 22:08:17 +0000 (18:08 -0400)] 
cpufreq: ppc_cbe_cpufreq_pmi: make the driver explicitly non-modular
The Kconfig for this driver is currently:
config CPU_FREQ_CBE_PMI
bool "CBE frequency scaling using PMI interface"
...meaning that it currently is not being built as a module by
anyone. Lets remove the modular and unused code here, so that
when reading the driver there is no doubt it is builtin-only.
Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.
We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki [Fri, 8 Apr 2016 23:08:02 +0000 (01:08 +0200)]
Merge branch 'pm-cpufreq-sched' into pm-cpufreq
Rafael J. Wysocki [Thu, 7 Apr 2016 21:38:46 +0000 (23:38 +0200)]
cpufreq: Call cpufreq_disable_fast_switch() in sugov_exit()
Due to differences in the cpufreq core's handling of runtime CPU
offline and nonboot CPUs disabling during system suspend-to-RAM,
fast frequency switching gets disabled after a suspend-to-RAM and
resume cycle on all of the nonboot CPUs.
To prevent that from happening, move the invocation of
cpufreq_disable_fast_switch() from cpufreq_exit_governor() to
sugov_exit(), as the schedutil governor is the only user of fast
frequency switching today anyway.
That simply prevents cpufreq_disable_fast_switch() from being called
without invoking the ->governor callback for the CPUFREQ_GOV_POLICY_EXIT
event (which happens during system suspend now).
Fixes: b7898fda5bc7 (cpufreq: Support for fast frequency switching)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Viresh Kumar [Thu, 24 Mar 2016 04:21:57 +0000 (09:51 +0530)]
cpufreq: dt: Drop stale comment
The comment in file header doesn't hold true anymore, drop it.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Srinivas Pandruvada [Sun, 3 Apr 2016 20:06:46 +0000 (13:06 -0700)] 
cpufreq: intel_pstate: Documenation for structures
No code change. Only added kernel doc style comments for structures.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Srinivas Pandruvada [Mon, 4 Apr 2016 02:42:11 +0000 (19:42 -0700)]
cpufreq: intel_pstate: fix inconsistency in setting policy limits
When user sets performance policy using cpufreq interface, it is possible
that because of policy->max limits, the actual performance is still
limited. But the current implementation will silently switch the
policy to powersave and start using powersave limits. If user modifies
any limits using intel_pstate sysfs, this is actually changing powersave
limits.
The current implementation tracks limits under powersave and performance
policy using two different variables. When policy->max is less than
policy->cpuinfo.max_freq, only powersave limit variable is used.
This fix causes the performance limits variable to be used always when
the policy is performance.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki [Fri, 1 Apr 2016 23:09:12 +0000 (01:09 +0200)]
cpufreq: schedutil: New governor based on scheduler utilization data
Add a new cpufreq scaling governor, called "schedutil", that uses
scheduler-provided CPU utilization information as input for making
its decisions.
Doing that is possible after commit
34e2c555f3e1 (cpufreq: Add
mechanism for registering utilization update callbacks) that
introduced cpufreq_update_util() called by the scheduler on
utilization changes (from CFS) and RT/DL task status updates.
In particular, CPU frequency scaling decisions may be based on
the the utilization data passed to cpufreq_update_util() by CFS.
The new governor is relatively simple.
The frequency selection formula used by it depends on whether or not
the utilization is frequency-invariant. In the frequency-invariant
case the new CPU frequency is given by
next_freq = 1.25 * max_freq * util / max
where util and max are the last two arguments of cpufreq_update_util().
In turn, if util is not frequency-invariant, the maximum frequency in
the above formula is replaced with the current frequency of the CPU:
next_freq = 1.25 * curr_freq * util / max
The coefficient 1.25 corresponds to the frequency tipping point at
(util / max) = 0.8.
All of the computations are carried out in the utilization update
handlers provided by the new governor. One of those handlers is
used for cpufreq policies shared between multiple CPUs and the other
one is for policies with one CPU only (and therefore it doesn't need
to use any extra synchronization means).
The governor supports fast frequency switching if that is supported
by the cpufreq driver in use and possible for the given policy.
In the fast switching case, all operations of the governor take
place in its utilization update handlers. If fast switching cannot
be used, the frequency switch operations are carried out with the
help of a work item which only calls __cpufreq_driver_target()
(under a mutex) to trigger a frequency update (to a value already
computed beforehand in one of the utilization update handlers).
Currently, the governor treats all of the RT and DL tasks as
"unknown utilization" and sets the frequency to the allowed
maximum when updated from the RT or DL sched classes. That
heavy-handed approach should be replaced with something more
subtle and specifically targeted at RT and DL tasks.
The governor shares some tunables management code with the
"ondemand" and "conservative" governors and uses some common
definitions from cpufreq_governor.h, but apart from that it
is stand-alone.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Rafael J. Wysocki [Wed, 30 Mar 2016 01:47:49 +0000 (03:47 +0200)]
cpufreq: Support for fast frequency switching
Modify the ACPI cpufreq driver to provide a method for switching
CPU frequencies from interrupt context and update the cpufreq core
to support that method if available.
Introduce a new cpufreq driver callback, ->fast_switch, to be
invoked for frequency switching from interrupt context by (future)
governors supporting that feature via (new) helper function
cpufreq_driver_fast_switch().
Add two new policy flags, fast_switch_possible, to be set by the
cpufreq driver if fast frequency switching can be used for the
given policy and fast_switch_enabled, to be set by the governor
if it is going to use fast frequency switching for the given
policy. Also add a helper for setting the latter.
Since fast frequency switching is inherently incompatible with
cpufreq transition notifiers, make it possible to set the
fast_switch_enabled only if there are no transition notifiers
already registered and make the registration of new transition
notifiers fail if fast_switch_enabled is set for at least one
policy.
Implement the ->fast_switch callback in the ACPI cpufreq driver
and make it set fast_switch_possible during policy initialization
as appropriate.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Tue, 22 Mar 2016 01:51:56 +0000 (02:51 +0100)]
cpufreq: Move governor symbols to cpufreq.h
Move definitions of symbols related to transition latency and
sampling rate to include/linux/cpufreq.h so they can be used by
(future) goverernors located outside of drivers/cpufreq/.
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Tue, 22 Mar 2016 01:50:45 +0000 (02:50 +0100)]
cpufreq: Move governor attribute set headers to cpufreq.h
Move definitions and function headers related to struct gov_attr_set
to include/linux/cpufreq.h so they can be used by (future) goverernors
located outside of drivers/cpufreq/.
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Tue, 22 Mar 2016 01:49:15 +0000 (02:49 +0100)]
cpufreq: governor: Move abstract gov_attr_set code to seperate file
Move abstract code related to struct gov_attr_set to a separate (new)
file so it can be shared with (future) goverernors that won't share
more code with "ondemand" and "conservative".
No intentional functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Tue, 22 Mar 2016 01:47:51 +0000 (02:47 +0100)]
cpufreq: governor: New data type for management part of dbs_data
In addition to fields representing governor tunables, struct dbs_data
contains some fields needed for the management of objects of that
type. As it turns out, that part of struct dbs_data may be shared
with (future) governors that won't use the common code used by
"ondemand" and "conservative", so move it to a separate struct type
and modify the code using struct dbs_data to follow.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Rafael J. Wysocki [Fri, 1 Apr 2016 23:08:43 +0000 (01:08 +0200)]
cpufreq: sched: Helpers to add and remove update_util hooks
Replace the single helper for adding and removing cpufreq utilization
update hooks, cpufreq_set_update_util_data(), with a pair of helpers,
cpufreq_add_update_util_hook() and cpufreq_remove_update_util_hook(),
and modify the users of cpufreq_set_update_util_data() accordingly.
With the new helpers, the code using them doesn't need to worry
about the internals of struct update_util_data and in particular
it doesn't need to worry about populating the func field in it
properly upfront.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Rafael J. Wysocki [Fri, 1 Apr 2016 23:07:17 +0000 (01:07 +0200)]
Merge back intel_pstate fixes for v4.6.
* pm-cpufreq:
intel_pstate: Avoid extra invocation of intel_pstate_sample()
intel_pstate: Do not set utilization update hook too early
Rafael J. Wysocki [Fri, 1 Apr 2016 23:06:21 +0000 (01:06 +0200)]
intel_pstate: Avoid extra invocation of intel_pstate_sample()
The initialization of intel_pstate for a given CPU involves populating
the fields of its struct cpudata that represent the previous sample,
but currently that is done in a problematic way.
Namely, intel_pstate_init_cpu() makes an extra call to
intel_pstate_sample() so it reads the current register values that
will be used to populate the "previous sample" record during the
next invocation of intel_pstate_sample(). However, after commit
a4675fbc4a7a (cpufreq: intel_pstate: Replace timers with utilization
update callbacks) that doesn't work for last_sample_time, because
the time value is passed to intel_pstate_sample() as an argument now.
Passing 0 to it from intel_pstate_init_cpu() is problematic, because
that causes cpu->last_sample_time == 0 to be visible in
get_target_pstate_use_performance() (and hence the extra
cpu->last_sample_time > 0 check in there) and effectively allows
the first invocation of intel_pstate_sample() from
intel_pstate_update_util() to happen immediately after the
initialization which may lead to a significant "turn on"
effect in the governor algorithm.
To mitigate that issue, rework the initialization to avoid the
extra intel_pstate_sample() call from intel_pstate_init_cpu().
Instead, make intel_pstate_sample() return false if it has been
called with cpu->sample.time equal to zero, which will make
intel_pstate_update_util() skip the sample in that case, and
reset cpu->sample.time from intel_pstate_set_update_util_hook()
to make the algorithm start properly every time the hook is set.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Rafael J. Wysocki [Thu, 31 Mar 2016 15:42:15 +0000 (17:42 +0200)]
intel_pstate: Do not set utilization update hook too early
The utilization update hook in the intel_pstate driver is set too
early, as it only should be set after the policy has been fully
initialized by the core. That may cause intel_pstate_update_util()
to use incorrect data and put the CPUs into incorrect P-states as
a result.
To prevent that from happening, make intel_pstate_set_policy() set
the utilization update hook instead of intel_pstate_init_cpu() so
intel_pstate_update_util() only runs when all things have been
initialized as appropriate.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Linus Torvalds [Sat, 26 Mar 2016 23:03:24 +0000 (16:03 -0700)] 
Linux 4.6-rc1
Linus Torvalds [Sat, 26 Mar 2016 22:53:16 +0000 (15:53 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/sage/ceph-client
Pull Ceph updates from Sage Weil:
"There is quite a bit here, including some overdue refactoring and
cleanup on the mon_client and osd_client code from Ilya, scattered
writeback support for CephFS and a pile of bug fixes from Zheng, and a
few random cleanups and fixes from others"
[ I already decided not to pull this because of it having been rebased
recently, but ended up changing my mind after all. Next time I'll
really hold people to it. Oh well. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (34 commits)
libceph: use KMEM_CACHE macro
ceph: use kmem_cache_zalloc
rbd: use KMEM_CACHE macro
ceph: use lookup request to revalidate dentry
ceph: kill ceph_get_dentry_parent_inode()
ceph: fix security xattr deadlock
ceph: don't request vxattrs from MDS
ceph: fix mounting same fs multiple times
ceph: remove unnecessary NULL check
ceph: avoid updating directory inode's i_size accidentally
ceph: fix race during filling readdir cache
libceph: use sizeof_footer() more
ceph: kill ceph_empty_snapc
ceph: fix a wrong comparison
ceph: replace CURRENT_TIME by current_fs_time()
ceph: scattered page writeback
libceph: add helper that duplicates last extent operation
libceph: enable large, variable-sized OSD requests
libceph: osdc->req_mempool should be backed by a slab pool
libceph: make r_request msg_size calculation clearer
...
Linus Torvalds [Sat, 26 Mar 2016 19:59:04 +0000 (12:59 -0700)]
Merge tag 'ofs-pull-tag-1' of git://git./linux/kernel/git/hubcap/linux
Pull orangefs filesystem from Mike Marshall.
This finally merges the long-pending orangefs filesystem, which has been
much cleaned up with input from Al Viro over the last six months. From
the documentation file:
"OrangeFS is an LGPL userspace scale-out parallel storage system. It
is ideal for large storage problems faced by HPC, BigData, Streaming
Video, Genomics, Bioinformatics.
Orangefs, originally called PVFS, was first developed in 1993 by Walt
Ligon and Eric Blumer as a parallel file system for Parallel Virtual
Machine (PVM) as part of a NASA grant to study the I/O patterns of
parallel programs.
Orangefs features include:
- Distributes file data among multiple file servers
- Supports simultaneous access by multiple clients
- Stores file data and metadata on servers using local file system
and access methods
- Userspace implementation is easy to install and maintain
- Direct MPI support
- Stateless"
see Documentation/filesystems/orangefs.txt for more in-depth details.
* tag 'ofs-pull-tag-1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux: (174 commits)
orangefs: fix orangefs_superblock locking
orangefs: fix do_readv_writev() handling of error halfway through
orangefs: have ->kill_sb() evict the VFS side of things first
orangefs: sanitize ->llseek()
orangefs-bufmap.h: trim unused junk
orangefs: saner calling conventions for getting a slot
orangefs_copy_{to,from}_bufmap(): don't pass bufmap pointer
orangefs: get rid of readdir_handle_s
ornagefs: ensure that truncate has an up to date inode size
orangefs: move code which sets i_link to orangefs_inode_getattr
orangefs: remove needless wrapper around GFP_KERNEL
orangefs: remove wrapper around mutex_lock(&inode->i_mutex)
orangefs: refactor inode type or link_target change detection
orangefs: use new getattr for revalidate and remove old getattr
orangefs: use new getattr in inode getattr and permission
orangefs: use new orangefs_inode_getattr to get size in write and llseek
orangefs: use new orangefs_inode_getattr to create new inodes
orangefs: rename orangefs_inode_getattr to orangefs_inode_old_getattr
orangefs: remove inode->i_lock wrapper
orangefs: put register_chrdev immediately before register_filesystem
...
Linus Torvalds [Sat, 26 Mar 2016 18:37:42 +0000 (11:37 -0700)]
Merge tag 'ntb-4.6' of git://github.com/jonmason/ntb
Pull NTB bug fixes from Jon Mason:
"NTB bug fixes for tasklet from spinning forever, link errors,
translation window setup, NULL ptr dereference, and ntb-perf errors.
Also, a modification to the driver API that makes _addr functions
optional"
* tag 'ntb-4.6' of git://github.com/jonmason/ntb:
NTB: Remove _addr functions from ntb_hw_amd
NTB: Make _addr functions optional in the API
NTB: Fix incorrect clean up routine in ntb_perf
NTB: Fix incorrect return check in ntb_perf
ntb: fix possible NULL dereference
ntb: add missing setup of translation window
ntb: stop link work when we do not have memory
ntb: stop tasklet from spinning forever during shutdown.
ntb: perf test: fix address space confusion
Linus Torvalds [Sat, 26 Mar 2016 18:31:01 +0000 (11:31 -0700)]
Merge tag 'scsi-misc' of git://git./linux/kernel/git/jejb/scsi
Pull more SCSI updates from James Bottomley:
"The only new stuff which missed the first pull request is an update to
the UFS driver.
The rest is an assortment of bug fixes and minor tweaks which appeared
recently (some are fixes for recent code and some are stuff spotted
recently by the checkers or the new gcc-6 compiler [most of Arnd's
stuff])"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (32 commits)
scsi_common: do not clobber fixed sense information
scsi: ufs: select CONFIG_NLS
scsi: fc: use get/put_unaligned64 for wwn access
fnic: move printk()s outside of the critical code section.
qla2xxx: avoid maybe_uninitialized warning
megaraid_sas: add missing curly braces in ioctl handler
lpfc: fix misleading indentation
scsi_transport_sas: add 'scsi_target_id' sysfs attribute
scsi_dh_alua: uninitialized variable in alua_check_vpd()
scsi: ufs-qcom: add printouts of testbus debug registers
scsi: ufs-qcom: enable/disable the device ref clock
scsi: ufs-qcom: set PA_Local_TX_LCC_Enable before link startup
scsi: ufs: add device quirk delay before putting UFS rails in LPM
scsi: ufs: fix leakage during link off state
scsi: ufs: tune UniPro parameters to optimize hibern8 exit time
scsi: ufs: handle non spec compliant bkops behaviour by device
scsi: ufs: add retry for query descriptors
scsi: ufs: add error recovery after DL NAC error
scsi: ufs: make error handling bit faster
scsi: ufs: disable vccq if it's not needed by UFS device
...
Linus Torvalds [Sat, 26 Mar 2016 17:13:05 +0000 (10:13 -0700)]
f2fs/crypto: fix xts_tweak initialization
Commit
0b81d07790726 ("fs crypto: move per-file encryption from f2fs
tree to fs/crypto") moved the f2fs crypto files to fs/crypto/ and
renamed the symbol prefixes from "f2fs_" to "fscrypt_" (and from "F2FS_"
to just "FS" for preprocessor symbols).
Because of the symbol renaming, it's a bit hard to see it as a file
move: use
git show -M30
0b81d07790726
to lower the rename detection to just 30% similarity and make git show
the files as renamed (the header file won't be shown as a rename even
then - since all it contains is symbol definitions, it looks almost
completely different).
Even with the renames showing as renames, the diffs are not all that
easy to read, since so much is just the renames. But Eric Biggers
noticed that it's not just all renames: the initialization of the
xts_tweak had been broken too, using the inode number rather than the
page offset.
That's not right - it makes the xfs_tweak the same for all pages of each
inode. It _might_ make sense to make the xfs_tweak contain both the
offset _and_ the inode number, but not just the inode number.
Reported-by: Eric Biggers <ebiggers3@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allen Hubbe [Mon, 21 Mar 2016 08:53:14 +0000 (04:53 -0400)] 
NTB: Remove _addr functions from ntb_hw_amd
Kernel zero day testing warned about address space confusion. A virtual
iomem address was used where a physical address is expected. The
offending functions implement an optional part of the api, so they are
removed. They can be added later, after testing.
Fixes: a1b3695820aa490e58915d720a1438069813008b
Signed-off-by: Allen Hubbe <Allen.Hubbe@emc.com>
Acked-by: Xiangliang Yu <Xiangliang.Yu@amd.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Al Viro [Fri, 25 Mar 2016 23:56:34 +0000 (19:56 -0400)] 
orangefs: fix orangefs_superblock locking
* switch orangefs_remount() to taking ORANGEFS_SB(sb) instead of sb
* remove from the list _before_ orangefs_unmount() - request_mutex
in the latter will make sure that nothing observed in the loop in
ORANGEFS_DEV_REMOUNT_ALL handling will get freed until the end
of loop
* on removal, keep the forward pointer and zero the back one. That
way we can drop and regain the spinlock in the loop body (again,
ORANGEFS_DEV_REMOUNT_ALL one) and still be able to get to the
rest of the list.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro [Wed, 17 Feb 2016 01:15:43 +0000 (20:15 -0500)]
orangefs: fix do_readv_writev() handling of error halfway through
Error should only be returned if nothing had been read/written.
Otherwise we need to report a short read/write instead.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro [Wed, 17 Feb 2016 02:08:29 +0000 (21:08 -0500)]
orangefs: have ->kill_sb() evict the VFS side of things first
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro [Wed, 17 Feb 2016 01:25:19 +0000 (20:25 -0500)]
orangefs: sanitize ->llseek()
a) open files can't have NULL inodes
b) it's SEEK_END, not ORANGEFS_SEEK_END; no need to get cute.
c) make_bad_inode() on lseek()?
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro [Wed, 17 Feb 2016 01:12:04 +0000 (20:12 -0500)]
orangefs-bufmap.h: trim unused junk
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro [Wed, 17 Feb 2016 01:10:26 +0000 (20:10 -0500)]
orangefs: saner calling conventions for getting a slot
just have it return the slot number or -E... - the caller checks
the sign anyway
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro [Wed, 17 Feb 2016 01:06:19 +0000 (20:06 -0500)]
orangefs_copy_{to,from}_bufmap(): don't pass bufmap pointer
it's always __orangefs_bufmap
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro [Wed, 17 Feb 2016 00:54:13 +0000 (19:54 -0500)]
orangefs: get rid of readdir_handle_s
no point, really - we couldn't keep those across the calls of
getdents(); it would be too easy to DoS, having all slots exhausted.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Linus Torvalds [Fri, 25 Mar 2016 23:59:11 +0000 (16:59 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge fourth patch-bomb from Andrew Morton:
"A lot more stuff than expected, sorry. A bunch of ocfs2 reviewing was
finished off.
- mhocko's oom-reaper out-of-memory-handler changes
- ocfs2 fixes and features
- KASAN feature work
- various fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (42 commits)
thp: fix typo in khugepaged_scan_pmd()
MAINTAINERS: fill entries for KASAN
mm/filemap: generic_file_read_iter(): check for zero reads unconditionally
kasan: test fix: warn if the UAF could not be detected in kmalloc_uaf2
mm, kasan: stackdepot implementation. Enable stackdepot for SLAB
arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
mm, kasan: add GFP flags to KASAN API
mm, kasan: SLAB support
kasan: modify kmalloc_large_oob_right(), add kmalloc_pagealloc_oob_right()
include/linux/oom.h: remove undefined oom_kills_count()/note_oom_kill()
mm/page_alloc: prevent merging between isolated and other pageblocks
drivers/memstick/host/r592.c: avoid gcc-6 warning
ocfs2: extend enough credits for freeing one truncate record while replaying truncate records
ocfs2: extend transaction for ocfs2_remove_rightmost_path() and ocfs2_update_edge_lengths() before to avoid inconsistency between inode and et
ocfs2/dlm: move lock to the tail of grant queue while doing in-place convert
ocfs2: solve a problem of crossing the boundary in updating backups
ocfs2: fix occurring deadlock by changing ocfs2_wq from global to local
ocfs2/dlm: fix BUG in dlm_move_lockres_to_recovery_list
ocfs2/dlm: fix race between convert and recovery
ocfs2: fix a deadlock issue in ocfs2_dio_end_io_write()
...
Linus Torvalds [Fri, 25 Mar 2016 23:55:37 +0000 (16:55 -0700)]
Merge tag 'pm+acpi-4.6-rc1-3' of git://git./linux/kernel/git/rafael/linux-pm
Pull power management fixlet from Rafael Wysocki:
"One of commits in my previous pull request changed the permissions of
drivers/power/avs/rockchip-io-domain.c to executable by mistake"
* tag 'pm+acpi-4.6-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Fix permissions of drivers/power/avs/rockchip-io-domain.c
Linus Torvalds [Fri, 25 Mar 2016 23:48:45 +0000 (16:48 -0700)]
Merge tag 'please-pull-preadv2' of git://git./linux/kernel/git/aegl/linux
Pull ia64 update from Tony Luck:
"Wire up new system calls p{read,write}v2 for ia64"
* tag 'please-pull-preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
[IA64] Enable preadv2 and pwritev2 syscalls for ia64
Linus Torvalds [Fri, 25 Mar 2016 23:39:05 +0000 (16:39 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input
Pull more input updates from Dmitry Torokhov:
"Second round of updates for the input subsystem.
The BYD PS/2 protocol driver now uses absolute reporting mode and
should behave more like other touchpads; Synaptics driver needed to
extend one of its quirks to a newer firmware version, and a few USB
drivers got tightened up checks for the contents of their descriptors"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: sur40 - fix DMA on stack
Input: ati_remote2 - fix crashes on detecting device with invalid descriptor
Input: synaptics - handle spurious release of trackstick buttons, again
Input: synaptics-rmi4 - remove check of Non-NULL array
Input: byd - enable absolute mode
Input: ims-pcu - sanity check against missing interfaces
Input: melfas_mip4 - add hw_version sysfs attribute
Kirill A. Shutemov [Fri, 25 Mar 2016 21:22:20 +0000 (14:22 -0700)] 
thp: fix typo in khugepaged_scan_pmd()
!PageLRU should lead to SCAN_PAGE_LRU, not SCAN_SCAN_ABORT result.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Ebru Akagunduz <ebru.akagunduz@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Ryabinin [Fri, 25 Mar 2016 21:22:17 +0000 (14:22 -0700)] 
MAINTAINERS: fill entries for KASAN
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nicolai Stange [Fri, 25 Mar 2016 21:22:14 +0000 (14:22 -0700)] 
mm/filemap: generic_file_read_iter(): check for zero reads unconditionally
If
- generic_file_read_iter() gets called with a zero read length,
- the read offset is at a page boundary,
- IOCB_DIRECT is not set
- and the page in question hasn't made it into the page cache yet,
then do_generic_file_read() will trigger a readahead with a req_size hint
of zero.
Since roundup_pow_of_two(0) is undefined, UBSAN reports
UBSAN: Undefined behaviour in include/linux/log2.h:63:13
shift exponent 64 is too large for 64-bit type 'long unsigned int'
CPU: 3 PID: 1017 Comm: sa1 Tainted: G L 4.5.0-next-
20160318+ #14
[...]
Call Trace:
[...]
[<
ffffffff813ef61a>] ondemand_readahead+0x3aa/0x3d0
[<
ffffffff813ef61a>] ? ondemand_readahead+0x3aa/0x3d0
[<
ffffffff813c73bd>] ? find_get_entry+0x2d/0x210
[<
ffffffff813ef9c3>] page_cache_sync_readahead+0x63/0xa0
[<
ffffffff813cc04d>] do_generic_file_read+0x80d/0xf90
[<
ffffffff813cc955>] generic_file_read_iter+0x185/0x420
[...]
[<
ffffffff81510b06>] __vfs_read+0x256/0x3d0
[...]
when get_init_ra_size() gets called from ondemand_readahead().
The net effect is that the initial readahead size is arch dependent for
requested read lengths of zero: for example, since
1UL << (sizeof(unsigned long) * 8)
evaluates to 1 on x86 while its result is 0 on ARMv7, the initial readahead
size becomes 4 on the former and 0 on the latter.
What's more, whether or not the file access timestamp is updated for zero
length reads is decided differently for the two cases of IOCB_DIRECT
being set or cleared: in the first case, generic_file_read_iter()
explicitly skips updating that timestamp while in the latter case, it is
always updated through the call to do_generic_file_read().
According to POSIX, zero length reads "do not modify the last data access
timestamp" and thus, the IOCB_DIRECT behaviour is POSIXly correct.
Let generic_file_read_iter() unconditionally check the requested read
length at its entry and return immediately with success if it is zero.
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander Potapenko [Fri, 25 Mar 2016 21:22:11 +0000 (14:22 -0700)] 
kasan: test fix: warn if the UAF could not be detected in kmalloc_uaf2
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander Potapenko [Fri, 25 Mar 2016 21:22:08 +0000 (14:22 -0700)]
mm, kasan: stackdepot implementation. Enable stackdepot for SLAB
Implement the stack depot and provide CONFIG_STACKDEPOT. Stack depot
will allow KASAN store allocation/deallocation stack traces for memory
chunks. The stack traces are stored in a hash table and referenced by
handles which reside in the kasan_alloc_meta and kasan_free_meta
structures in the allocated memory chunks.
IRQ stack traces are cut below the IRQ entry point to avoid unnecessary
duplication.
Right now stackdepot support is only enabled in SLAB allocator. Once
KASAN features in SLAB are on par with those in SLUB we can switch SLUB
to stackdepot as well, thus removing the dependency on SLUB stack
bookkeeping, which wastes a lot of memory.
This patch is based on the "mm: kasan: stack depots" patch originally
prepared by Dmitry Chernenkov.
Joonsoo has said that he plans to reuse the stackdepot code for the
mm/page_owner.c debugging facility.
[akpm@linux-foundation.org: s/depot_stack_handle/depot_stack_handle_t]
[aryabinin@virtuozzo.com: comment style fixes]
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander Potapenko [Fri, 25 Mar 2016 21:22:05 +0000 (14:22 -0700)]
arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.
Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>. Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander Potapenko [Fri, 25 Mar 2016 21:22:02 +0000 (14:22 -0700)]
mm, kasan: add GFP flags to KASAN API
Add GFP flags to KASAN hooks for future patches to use.
This patch is based on the "mm: kasan: unified support for SLUB and SLAB
allocators" patch originally prepared by Dmitry Chernenkov.
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander Potapenko [Fri, 25 Mar 2016 21:21:59 +0000 (14:21 -0700)]
mm, kasan: SLAB support
Add KASAN hooks to SLAB allocator.
This patch is based on the "mm: kasan: unified support for SLUB and SLAB
allocators" patch originally prepared by Dmitry Chernenkov.
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander Potapenko [Fri, 25 Mar 2016 21:21:56 +0000 (14:21 -0700)]
kasan: modify kmalloc_large_oob_right(), add kmalloc_pagealloc_oob_right()
This patchset implements SLAB support for KASAN
Unlike SLUB, SLAB doesn't store allocation/deallocation stacks for heap
objects, therefore we reimplement this feature in mm/kasan/stackdepot.c.
The intention is to ultimately switch SLUB to use this implementation as
well, which will save a lot of memory (right now SLUB bloats each object
by 256 bytes to store the allocation/deallocation stacks).
Also neither SLUB nor SLAB delay the reuse of freed memory chunks, which
is necessary for better detection of use-after-free errors. We
introduce memory quarantine (mm/kasan/quarantine.c), which allows
delayed reuse of deallocated memory.
This patch (of 7):
Rename kmalloc_large_oob_right() to kmalloc_pagealloc_oob_right(), as
the test only checks the page allocator functionality. Also reimplement
kmalloc_large_oob_right() so that the test allocates a large enough
chunk of memory that still does not trigger the page allocator fallback.
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tetsuo Handa [Fri, 25 Mar 2016 21:21:53 +0000 (14:21 -0700)] 
include/linux/oom.h: remove undefined oom_kills_count()/note_oom_kill()
A leftover from commit
c32b3cbe0d06 ("oom, PM: make OOM detection in the
freezer path raceless").
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Fri, 25 Mar 2016 21:21:50 +0000 (14:21 -0700)] 
mm/page_alloc: prevent merging between isolated and other pageblocks
Hanjun Guo has reported that a CMA stress test causes broken accounting of
CMA and free pages:
> Before the test, I got:
> -bash-4.3# cat /proc/meminfo | grep Cma
> CmaTotal: 204800 kB
> CmaFree: 195044 kB
>
>
> After running the test:
> -bash-4.3# cat /proc/meminfo | grep Cma
> CmaTotal: 204800 kB
> CmaFree:
6602584 kB
>
> So the freed CMA memory is more than total..
>
> Also the the MemFree is more than mem total:
>
> -bash-4.3# cat /proc/meminfo
> MemTotal:
16342016 kB
> MemFree:
22367268 kB
> MemAvailable:
22370528 kB
Laura Abbott has confirmed the issue and suspected the freepage accounting
rewrite around 3.18/4.0 by Joonsoo Kim. Joonsoo had a theory that this is
caused by unexpected merging between MIGRATE_ISOLATE and MIGRATE_CMA
pageblocks:
> CMA isolates MAX_ORDER aligned blocks, but, during the process,
> partialy isolated block exists. If MAX_ORDER is 11 and
> pageblock_order is 9, two pageblocks make up MAX_ORDER
> aligned block and I can think following scenario because pageblock
> (un)isolation would be done one by one.
>
> (each character means one pageblock. 'C', 'I' means MIGRATE_CMA,
> MIGRATE_ISOLATE, respectively.
>
> CC -> IC -> II (Isolation)
> II -> CI -> CC (Un-isolation)
>
> If some pages are freed at this intermediate state such as IC or CI,
> that page could be merged to the other page that is resident on
> different type of pageblock and it will cause wrong freepage count.
This was supposed to be prevented by CMA operating on MAX_ORDER blocks,
but since it doesn't hold the zone->lock between pageblocks, a race
window does exist.
It's also likely that unexpected merging can occur between
MIGRATE_ISOLATE and non-CMA pageblocks. This should be prevented in
__free_one_page() since commit
3c605096d315 ("mm/page_alloc: restrict
max order of merging on isolated pageblock"). However, we only check
the migratetype of the pageblock where buddy merging has been initiated,
not the migratetype of the buddy pageblock (or group of pageblocks)
which can be MIGRATE_ISOLATE.
Joonsoo has suggested checking for buddy migratetype as part of
page_is_buddy(), but that would add extra checks in allocator hotpath
and bloat-o-meter has shown significant code bloat (the function is
inline).
This patch reduces the bloat at some expense of more complicated code.
The buddy-merging while-loop in __free_one_page() is initially bounded
to pageblock_border and without any migratetype checks. The checks are
placed outside, bumping the max_order if merging is allowed, and
returning to the while-loop with a statement which can't be possibly
considered harmful.
This fixes the accounting bug and also removes the arguably weird state
in the original commit
3c605096d315 where buddies could be left
unmerged.
Fixes: 3c605096d315 ("mm/page_alloc: restrict max order of merging on isolated pageblock")
Link: https://lkml.org/lkml/2016/3/2/280
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Hanjun Guo <guohanjun@huawei.com>
Tested-by: Hanjun Guo <guohanjun@huawei.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Debugged-by: Laura Abbott <labbott@redhat.com>
Debugged-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> [3.18+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Arnd Bergmann [Fri, 25 Mar 2016 21:21:47 +0000 (14:21 -0700)] 
drivers/memstick/host/r592.c: avoid gcc-6 warning
The r592 driver relies on behavior of the DMA mapping API that is
normally observed but not guaranteed by the API. Instead it uses a
runtime check to fail transfers if the API ever behaves
When CONFIG_NEED_SG_DMA_LENGTH is not set, one of the checks turns into a
comparison of a variable with itself, which gcc-6.0 now warns about:
drivers/memstick/host/r592.c: In function 'r592_transfer_fifo_dma':
drivers/memstick/host/r592.c:302:31: error: self-comparison always evaluates to false [-Werror=tautological-compare]
(sg_dma_len(&dev->req->sg) < dev->req->sg.length)) {
^
The check itself is not a problem, so this patch just rephrases the
condition in a way that gcc does not consider an indication of a mistake.
We already know that dev->req->sg.length was initially R592_LFIFO_SIZE, so
we can compare it to that constant again.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Maxim Levitsky <maximlevitsky@gmail.com>
Cc: Quentin Lambert <lambert.quentin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xue jiufei [Fri, 25 Mar 2016 21:21:44 +0000 (14:21 -0700)] 
ocfs2: extend enough credits for freeing one truncate record while replaying truncate records
Now function ocfs2_replay_truncate_records() first modifies tl_used,
then calls ocfs2_extend_trans() to extend transactions for gd and alloc
inode used for freeing clusters. jbd2_journal_restart() may be called
and it may happen that tl_used in truncate log is decreased but the
clusters are not freed, which means these clusters are lost. So we
should avoid extending transactions in these two operations.
Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Acked-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Xue jiufei [Fri, 25 Mar 2016 21:21:41 +0000 (14:21 -0700)]
ocfs2: extend transaction for ocfs2_remove_rightmost_path() and ocfs2_update_edge_lengths() before to avoid inconsistency between inode and et
I found that jbd2_journal_restart() is called in some places without
keeping things consistently before. However, jbd2_journal_restart() may
commit the handle's transaction and restart another one. If the first
transaction is committed successfully while another not, it may cause
filesystem inconsistency or read only. This is an effort to fix this
kind of problems.
This patch (of 3):
The following functions will be called while truncating an extent:
ocfs2_remove_btree_range
-> ocfs2_start_trans
-> ocfs2_remove_extent
-> ocfs2_truncate_rec
-> ocfs2_extend_rotate_transaction
-> jbd2_journal_restart if jbd2_journal_extend fail
-> ocfs2_rotate_tree_left
-> ocfs2_remove_rightmost_path
-> ocfs2_extend_rotate_transaction
-> ocfs2_unlink_subtree
-> ocfs2_update_edge_lengths
-> ocfs2_extend_trans
-> jbd2_journal_restart if jbd2_journal_extend fail
-> ocfs2_et_update_clusters
-> ocfs2_commit_trans
jbd2_journal_restart() may be called and it may happened that the buffers
dirtied in ocfs2_truncate_rec() are committed while buffers dirtied in
ocfs2_et_update_clusters() are not, the total clusters on extent tree and
i_clusters in ocfs2_dinode is inconsistency. So the clusters got from
ocfs2_dinode is incorrect, and it also cause read-only problem when call
ocfs2_commit_truncate() with the error message: "Inode %llu has empty
extent block at %llu".
We should extend enough credits for function ocfs2_remove_rightmost_path
and ocfs2_update_edge_lengths to avoid this inconsistency.
Signed-off-by: joyce.xue <xuejiufei@huawei.com>
Acked-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xuejiufei [Fri, 25 Mar 2016 21:21:38 +0000 (14:21 -0700)]
ocfs2/dlm: move lock to the tail of grant queue while doing in-place convert
We have found a bug when two nodes doing umount one after another.
1) Node 1 migrate a lockres that has 3 locks in grant queue such as
N2(PR)<->N3(NL)<->N4(PR) to N2. After migration, lvb of the lock
N3(NL) and N4(PR) are empty on node 2 because migration target do not
copy lvb to these two lock.
2) Node 3 want to convert to PR, it can be granted in
__dlmconvert_master(), and the order of these locks is unchanged. The
lvb of the lock N3(PR) on node 2 is copyed from lockres in function
dlm_update_lvb() while the lvb of lock N4(PR) is still empty.
3) Node 2 want to leave domain, it will migrate this lockres to node 3.
Then node 2 will trigger the BUG in dlm_prepare_lvb_for_migration()
when adding the lock N4(PR) to mres with the following message because
the lvb of mres is already copied from lock N3(PR), but the lvb of lock
N4(PR) is empty.
"Mismatched lvb in lock cookie=%u:%llu, name=%.*s, node=%u"
[akpm@linux-foundation.org: tweak comment]
Signed-off-by: xuejiufei <xuejiufei@huawei.com>
Acked-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
jiangyiwen [Fri, 25 Mar 2016 21:21:35 +0000 (14:21 -0700)] 
ocfs2: solve a problem of crossing the boundary in updating backups
In update_backups() there exists a problem of crossing the boundary as
follows:
we assume that lun will be resized to 1TB(cluster_size is 32kb), it will
include 0~
33554431 cluster, in update_backups func, it will backup super
block in location of 1TB which is the 33554432th cluster, so the
phenomenon of crossing the boundary happens.
Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Xue jiufei <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
jiangyiwen [Fri, 25 Mar 2016 21:21:32 +0000 (14:21 -0700)]
ocfs2: fix occurring deadlock by changing ocfs2_wq from global to local
This patch fixes a deadlock, as follows:
Node 1 Node 2 Node 3
1)volume a and b are only mount vol a only mount vol b
mounted
2) start to mount b start to mount a
3) check hb of Node 3 check hb of Node 2
in vol a, qs_holds++ in vol b, qs_holds++
4) -------------------- all nodes' network down --------------------
5) progress of mount b the same situation as
failed, and then call Node 2
ocfs2_dismount_volume.
but the process is hung,
since there is a work
in ocfs2_wq cannot beo
completed. This work is
about vol a, because
ocfs2_wq is global wq.
BTW, this work which is
scheduled in ocfs2_wq is
ocfs2_orphan_scan_work,
and the context in this work
needs to take inode lock
of orphan_dir, because
lockres owner are Node 1 and
all nodes' nework has been down
at the same time, so it can't
get the inode lock.
6) Why can't this node be fenced
when network disconnected?
Because the process of
mount is hung what caused qs_holds
is not equal 0.
Because all works in the ocfs2_wq are relative to the super block.
The solution is to change the ocfs2_wq from global to local. In other
words, move it into struct ocfs2_super.
Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Xue jiufei <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joseph Qi [Fri, 25 Mar 2016 21:21:29 +0000 (14:21 -0700)] 
ocfs2/dlm: fix BUG in dlm_move_lockres_to_recovery_list
When master handles convert request, it queues ast first and then
returns status. This may happen that the ast is sent before the request
status because the above two messages are sent by two threads. And
right after the ast is sent, if master down, it may trigger BUG in
dlm_move_lockres_to_recovery_list in the requested node because ast
handler moves it to grant list without clear lock->convert_pending. So
remove BUG_ON statement and check if the ast is processed in
dlmconvert_remote.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reported-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Tariq Saeed <tariq.x.saeed@oracle.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joseph Qi [Fri, 25 Mar 2016 21:21:26 +0000 (14:21 -0700)]
ocfs2/dlm: fix race between convert and recovery
There is a race window between dlmconvert_remote and
dlm_move_lockres_to_recovery_list, which will cause a lock with
OCFS2_LOCK_BUSY in grant list, thus system hangs.
dlmconvert_remote
{
spin_lock(&res->spinlock);
list_move_tail(&lock->list, &res->converting);
lock->convert_pending = 1;
spin_unlock(&res->spinlock);
status = dlm_send_remote_convert_request();
>>>>>> race window, master has queued ast and return DLM_NORMAL,
and then down before sending ast.
this node detects master down and calls
dlm_move_lockres_to_recovery_list, which will revert the
lock to grant list.
Then OCFS2_LOCK_BUSY won't be cleared as new master won't
send ast any more because it thinks already be authorized.
spin_lock(&res->spinlock);
lock->convert_pending = 0;
if (status != DLM_NORMAL)
dlm_revert_pending_convert(res, lock);
spin_unlock(&res->spinlock);
}
In this case, check if res->state has DLM_LOCK_RES_RECOVERING bit set
(res is still in recovering) or res master changed (new master has
finished recovery), reset the status to DLM_RECOVERING, then it will
retry convert.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Reported-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Tariq Saeed <tariq.x.saeed@oracle.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:23 +0000 (14:21 -0700)] 
ocfs2: fix a deadlock issue in ocfs2_dio_end_io_write()
The code should call ocfs2_free_alloc_context() to free meta_ac &
data_ac before calling ocfs2_run_deallocs(). Because
ocfs2_run_deallocs() will acquire the system inode's i_mutex hold by
meta_ac. So try to release the lock before ocfs2_run_deallocs().
Fixes: af1310367f41 ("ocfs2: fix sparse file & data ordering issue in direct io.")
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Acked-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:20 +0000 (14:21 -0700)]
ocfs2: fix disk file size and memory file size mismatch
When doing append direct write in an already allocated cluster, and fast
path in ocfs2_dio_get_block() is triggered, function
ocfs2_dio_end_io_write() will be skipped as there is no context
allocated.
As a result, the disk file size will not be changed as it should be.
The solution is to skip fast path when we are about to change file size.
Fixes: af1310367f41 ("ocfs2: fix sparse file & data ordering issue in direct io.")
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Acked-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:18 +0000 (14:21 -0700)]
ocfs2: take ip_alloc_sem in ocfs2_dio_get_block & ocfs2_dio_end_io_write
Take ip_alloc_sem to prevent concurrent access to extent tree, which may
cause the extent tree in an unstable state.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:15 +0000 (14:21 -0700)]
ocfs2: fix ip_unaligned_aio deadlock with dio work queue
In the current implementation of unaligned aio+dio, lock order behave as
follow:
in user process context:
-> call io_submit()
-> get i_mutex
<== window1
-> get ip_unaligned_aio
-> submit direct io to block device
-> release i_mutex
-> io_submit() return
in dio work queue context(the work queue is created in __blockdev_direct_IO):
-> release ip_unaligned_aio
<== window2
-> get i_mutex
-> clear unwritten flag & change i_size
-> release i_mutex
There is a limitation to the thread number of dio work queue. 256 at
default. If all 256 thread are in the above 'window2' stage, and there
is a user process in the 'window1' stage, the system will became
deadlock. Since the user process hold i_mutex to wait ip_unaligned_aio
lock, while there is a direct bio hold ip_unaligned_aio mutex who is
waiting for a dio work queue thread to be schedule. But all the dio
work queue thread is waiting for i_mutex lock in 'window2'.
This case only happened in a test which send a large number(more than
256) of aio at one io_submit() call.
My design is to remove ip_unaligned_aio lock. Change it to a sync io
instead. Just like ip_unaligned_aio lock, serialize the unaligned aio
dio.
[akpm@linux-foundation.org: remove OCFS2_IOCB_UNALIGNED_IO, per Junxiao Bi]
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:12 +0000 (14:21 -0700)]
ocfs2: code clean up for direct io
Clean up ocfs2_file_write_iter & ocfs2_prepare_inode_for_write:
* remove append dio check: it will be checked in ocfs2_direct_IO()
* remove file hole check: file hole is supported for now
* remove inline data check: it will be checked in ocfs2_direct_IO()
* remove the full_coherence check when append dio: we will get the
inode_lock in ocfs2_dio_get_block, there is no need to fall back to
buffer io to ensure the coherence semantics.
Now the drop dio procedure is gone. :)
[akpm@linux-foundation.org: remove unused label]
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:09 +0000 (14:21 -0700)]
ocfs2: fix sparse file & data ordering issue in direct io
There are mainly three issues in the direct io code path after commit
24c40b329e03 ("ocfs2: implement ocfs2_direct_IO_write"):
* Does not support sparse file.
* Does not support data ordering. eg: when write to a file hole, it
will alloc extent first. If system crashed before io finished, data
will corrupt.
* Potential risk when doing aio+dio. The -EIOCBQUEUED return value is
likely to be ignored by ocfs2_direct_IO_write().
To resolve above problems, re-design direct io code with following ideas:
* Use buffer io to fill in holes. And this will make better
performance also.
* Clear unwritten after direct write finished. So we can make sure
meta data changes after data write to disk. (Unwritten extent is
invisible to user, from user's view, meta data is not changed when
allocate an unwritten extent.)
* Clear ocfs2_direct_IO_write(). Do all ending work in end_io.
This patch has passed fs,dio,ltp-aiodio.part1,ltp-aiodio.part2,ltp-aiodio.part4
test cases of ltp.
For performance improvement, see following test result:
ocfs2 cluster size 1MB, ocfs2 volume is mounted on /mnt/.
The original way:
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=4K count=
1048576 oflag=direct
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB) copied, 1707.83 s, 2.5 MB/s
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=256K count=16384 oflag=direct
16384+0 records in
16384+0 records out
4294967296 bytes (4.3 GB) copied, 582.705 s, 7.4 MB/s
After this patch:
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=4K count=
1048576 oflag=direct
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB) copied, 64.6412 s, 66.4 MB/s
+ rm /mnt/test.img -f
+ dd if=/dev/zero of=/mnt/test.img bs=256K count=16384 oflag=direct
16384+0 records in
16384+0 records out
4294967296 bytes (4.3 GB) copied, 34.7611 s, 124 MB/s
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:06 +0000 (14:21 -0700)]
ocfs2: record UNWRITTEN extents when populate write desc
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
There is still one issue in the direct write procedure.
phase 1: alloc extent with UNWRITTEN flag
phase 2: submit direct data to disk, add zero page to page cache
phase 3: clear UNWRITTEN flag when data has been written to disk
When there are 2 direct write A(0~3KB),B(4~7KB) writing to the same
cluster 0~7KB (cluster size 8KB). Write request A arrive phase 2 first,
it will zero the region (4~7KB). Before request A enter to phase 3,
request B arrive phase 2, it will zero region (0~3KB). This is just like
request B steps request A.
To resolve this issue, we should let request B knows this cluster is already
under zero, to prevent it from steps the previous write request.
This patch will add function ocfs2_unwritten_check() to do this job. It
will record all clusters that are under direct write(it will be recorded
in the 'ip_unwritten_list' member of inode info), and prevent the later
direct write writing to the same cluster to do the zero work again.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:03 +0000 (14:21 -0700)]
ocfs2: return the physical address in ocfs2_write_cluster
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
Direct io needs to get the physical address from write_begin, to map the
user page. This patch is to change the arg 'phys' of
ocfs2_write_cluster to a pointer, so it can be retrieved to write_begin.
And we can retrieve it to the direct io procedure.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:21:01 +0000 (14:21 -0700)]
ocfs2: do not change i_size in write_end for direct io
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
Append direct io do not change i_size in get block phase. It only move
to orphan when starting write. After data is written to disk, it will
delete itself from orphan and update i_size. So skip i_size change
section in write_begin for direct io.
And when there is no extents alloc, no meta data changes needed for
direct io (since write_begin start trans for 2 reason: alloc extents &
change i_size. Now none of them needed). So we can skip start trans
procedure.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:20:58 +0000 (14:20 -0700)]
ocfs2: test target page before change it
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
Direct io data will not appear in buffer. The w_target_page member will
not be filled by direct io. So avoid to use it when it's NULL. Unlinke
buffer io and mmap, direct io will call write_begin with more than 1
page a time. So the target_index is not sufficient to describe the
actual data. change it to a range start at target_index, end in
end_index.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:20:55 +0000 (14:20 -0700)]
ocfs2: use c_new to indicate newly allocated extents
To support direct io in ocfs2_write_begin_nolock & ocfs2_write_end_nolock.
There is a problem in ocfs2's direct io implement: if system crashed
after extents allocated, and before data return, we will get a extent
with dirty data on disk. This problem violate the journal=order
semantics, which means meta changes take effect after data written to
disk. To resolve this issue, direct write can use the UNWRITTEN flag to
describe a extent during direct data writeback. The direct write
procedure should act in the following order:
phase 1: alloc extent with UNWRITTEN flag
phase 2: submit direct data to disk, add zero page to page cache
phase 3: clear UNWRITTEN flag when data has been written to disk
This patch is to change the 'c_unwritten' member of
ocfs2_write_cluster_desc to 'c_clear_unwritten'. Means whether to clear
the unwritten flag. It do not care if a extent is allocated or not.
And use 'c_new' to specify a newly allocated extent. So the direct io
procedure can use c_clear_unwritten to control the UNWRITTEN bit on
extent.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ryan Ding [Fri, 25 Mar 2016 21:20:52 +0000 (14:20 -0700)]
ocfs2: add ocfs2_write_type_t type to identify the caller of write
Patchset: fix ocfs2 direct io code patch to support sparse file and data
ordering semantics
The idea is to use buffer io(more precisely use the interface
ocfs2_write_begin_nolock & ocfs2_write_end_nolock) to do the zero work
beyond block size. And clear UNWRITTEN flag until direct io data has
been written to disk, which can prevent data corruption when system
crashed during direct write.
And we will also archive a better performance: eg. dd direct write new
file with block size 4KB: before this patchset:
2.5 MB/s
after this patchset:
66.4 MB/s
This patch (of 8):
To support direct io in ocfs2_write_begin_nolock &
ocfs2_write_end_nolock.
Remove unused args filp & flags. Add new arg type. The type is one of
buffer/direct/mmap. Indicate 3 way to perform write. buffer/mmap type
has implemented. direct type will be implemented later.
Signed-off-by: Ryan Ding <ryan.ding@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Junxiao Bi [Fri, 25 Mar 2016 21:20:50 +0000 (14:20 -0700)] 
ocfs2: o2hb: fix double free bug
This is a regression issue and caused the following kernel panic when do
ocfs2 multiple test.
BUG: unable to handle kernel paging request at
00000002000800c0
IP: [<
ffffffff81192978>] kmem_cache_alloc+0x78/0x160
PGD
7bbe5067 PUD 0
Oops: 0000 [#1] SMP
Modules linked in: ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi xen_kbdfront xen_netfront xen_fbfront xen_blkfront
CPU: 2 PID: 4044 Comm: mpirun Not tainted 4.5.0-rc5-next-
20160225 #1
Hardware name: Xen HVM domU, BIOS 4.3.1OVM 05/14/2014
task:
ffff88007a521a80 ti:
ffff88007aed0000 task.ti:
ffff88007aed0000
RIP: 0010:[<
ffffffff81192978>] [<
ffffffff81192978>] kmem_cache_alloc+0x78/0x160
RSP: 0018:
ffff88007aed3a48 EFLAGS:
00010282
RAX:
0000000000000000 RBX:
0000000000000000 RCX:
0000000000001991
RDX:
0000000000001990 RSI:
00000000024000c0 RDI:
000000000001b330
RBP:
ffff88007aed3a98 R08:
ffff88007d29b330 R09:
00000002000800c0
R10:
0000000c51376d87 R11:
ffff8800792cac38 R12:
ffff88007cc30f00
R13:
00000000024000c0 R14:
ffffffff811b053f R15:
ffff88007aed3ce7
FS:
0000000000000000(0000) GS:
ffff88007d280000(0000) knlGS:
0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
CR2:
00000002000800c0 CR3:
000000007aeb2000 CR4:
00000000000406e0
Call Trace:
__d_alloc+0x2f/0x1a0
d_alloc+0x17/0x80
lookup_dcache+0x8a/0xc0
path_openat+0x3c3/0x1210
do_filp_open+0x80/0xe0
do_sys_open+0x110/0x200
SyS_open+0x19/0x20
do_syscall_64+0x72/0x230
entry_SYSCALL64_slow_path+0x25/0x25
Code: 05 e6 77 e7 7e 4d 8b 08 49 8b 40 10 4d 85 c9 0f 84 dd 00 00 00 48 85 c0 0f 84 d4 00 00 00 49 63 44 24 20 49 8b 3c 24 48 8d 4a 01 <49> 8b 1c 01 4c 89 c8 65 48 0f c7 0f 0f 94 c0 3c 01 75 b6 49 63
RIP kmem_cache_alloc+0x78/0x160
CR2:
00000002000800c0
---[ end trace
823969e602e4aaac ]---
Fixes: a4a1dfa4bb8b("ocfs2/cluster: fix memory leak in o2hb_region_release")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Fri, 25 Mar 2016 21:20:47 +0000 (14:20 -0700)] 
drivers/input: eliminate INPUT_COMPAT_TEST macro
INPUT_COMPAT_TEST became much simpler after commit
f4056b52845283
("input: redefine INPUT_COMPAT_TEST as in_compat_syscall()") so we can
cleanly eliminate it altogether.
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tetsuo Handa [Fri, 25 Mar 2016 21:20:44 +0000 (14:20 -0700)]
oom, oom_reaper: protect oom_reaper_list using simpler way
"oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task" tried
to protect oom_reaper_list using MMF_OOM_KILLED flag. But we can do it
by simply checking tsk->oom_reaper_list != NULL.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:41 +0000 (14:20 -0700)] 
oom: make oom_reaper freezable
After "oom: clear TIF_MEMDIE after oom_reaper managed to unmap the
address space" oom_reaper will call exit_oom_victim on the target task
after it is done. This might however race with the PM freezer:
CPU0 CPU1 CPU2
freeze_processes
try_to_freeze_tasks
# Allocation request
out_of_memory
oom_killer_disable
wake_oom_reaper(P1)
__oom_reap_task
exit_oom_victim(P1)
wait_event(oom_victims==0)
[...]
do_exit(P1)
perform IO/interfere with the freezer
which breaks the oom_killer_disable semantic. We no longer have a
guarantee that the oom victim won't interfere with the freezer because
it might be anywhere on the way to do_exit while the freezer thinks the
task has already terminated. It might trigger IO or touch devices which
are frozen already.
In order to close this race, make the oom_reaper thread freezable. This
will work because
a) already running oom_reaper will block freezer to enter the
quiescent state
b) wake_oom_reaper will not wake up the reaper after it has been
frozen
c) the only way to call exit_oom_victim after try_to_freeze_tasks
is from the oom victim's context when we know the further
interference shouldn't be possible
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Fri, 25 Mar 2016 21:20:39 +0000 (14:20 -0700)] 
oom: make oom_reaper_list single linked
Entries are only added/removed from oom_reaper_list at head so we can
use a single linked list and hence save a word in task_struct.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:36 +0000 (14:20 -0700)]
oom, oom_reaper: disable oom_reaper for oom_kill_allocating_task
Tetsuo has reported that oom_kill_allocating_task=1 will cause
oom_reaper_list corruption because oom_kill_process doesn't follow
standard OOM exclusion (aka ignores TIF_MEMDIE) and allows to enqueue
the same task multiple times - e.g. by sacrificing the same child
multiple times.
This patch fixes the issue by introducing a new MMF_OOM_KILLED mm flag
which is set in oom_kill_process atomically and oom reaper is disabled
if the flag was already set.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:33 +0000 (14:20 -0700)]
mm, oom_reaper: implement OOM victims queuing
wake_oom_reaper has allowed only 1 oom victim to be queued. The main
reason for that was the simplicity as other solutions would require some
way of queuing. The current approach is racy and that was deemed
sufficient as the oom_reaper is considered a best effort approach to
help with oom handling when the OOM victim cannot terminate in a
reasonable time. The race could lead to missing an oom victim which can
get stuck
out_of_memory
wake_oom_reaper
cmpxchg // OK
oom_reaper
oom_reap_task
__oom_reap_task
oom_victim terminates
atomic_inc_not_zero // fail
out_of_memory
wake_oom_reaper
cmpxchg // fails
task_to_reap = NULL
This race requires 2 OOM invocations in a short time period which is not
very likely but certainly not impossible. E.g. the original victim
might have not released a lot of memory for some reason.
The situation would improve considerably if wake_oom_reaper used a more
robust queuing. This is what this patch implements. This means adding
oom_reaper_list list_head into task_struct (eat a hole before embeded
thread_struct for that purpose) and a oom_reaper_lock spinlock for
queuing synchronization. wake_oom_reaper will then add the task on the
queue and oom_reaper will dequeue it.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:30 +0000 (14:20 -0700)]
mm, oom_reaper: report success/failure
Inform about the successful/failed oom_reaper attempts and dump all the
held locks to tell us more who is blocking the progress.
[akpm@linux-foundation.org: fix CONFIG_MMU=n build]
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:27 +0000 (14:20 -0700)]
oom: clear TIF_MEMDIE after oom_reaper managed to unmap the address space
When oom_reaper manages to unmap all the eligible vmas there shouldn't
be much of the freable memory held by the oom victim left anymore so it
makes sense to clear the TIF_MEMDIE flag for the victim and allow the
OOM killer to select another task.
The lack of TIF_MEMDIE also means that the victim cannot access memory
reserves anymore but that shouldn't be a problem because it would get
the access again if it needs to allocate and hits the OOM killer again
due to the fatal_signal_pending resp. PF_EXITING check. We can safely
hide the task from the OOM killer because it is clearly not a good
candidate anymore as everyhing reclaimable has been torn down already.
This patch will allow to cap the time an OOM victim can keep TIF_MEMDIE
and thus hold off further global OOM killer actions granted the oom
reaper is able to take mmap_sem for the associated mm struct. This is
not guaranteed now but further steps should make sure that mmap_sem for
write should be blocked killable which will help to reduce such a lock
contention. This is not done by this patch.
Note that exit_oom_victim might be called on a remote task from
__oom_reap_task now so we have to check and clear the flag atomically
otherwise we might race and underflow oom_victims or wake up waiters too
early.
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michal Hocko [Fri, 25 Mar 2016 21:20:24 +0000 (14:20 -0700)]
mm, oom: introduce oom reaper
This patch (of 5):
This is based on the idea from Mel Gorman discussed during LSFMM 2015
and independently brought up by Oleg Nesterov.
The OOM killer currently allows to kill only a single task in a good
hope that the task will terminate in a reasonable time and frees up its
memory. Such a task (oom victim) will get an access to memory reserves
via mark_oom_victim to allow a forward progress should there be a need
for additional memory during exit path.
It has been shown (e.g. by Tetsuo Handa) that it is not that hard to
construct workloads which break the core assumption mentioned above and
the OOM victim might take unbounded amount of time to exit because it
might be blocked in the uninterruptible state waiting for an event (e.g.
lock) which is blocked by another task looping in the page allocator.
This patch reduces the probability of such a lockup by introducing a
specialized kernel thread (oom_reaper) which tries to reclaim additional
memory by preemptively reaping the anonymous or swapped out memory owned
by the oom victim under an assumption that such a memory won't be needed
when its owner is killed and kicked from the userspace anyway. There is
one notable exception to this, though, if the OOM victim was in the
process of coredumping the result would be incomplete. This is
considered a reasonable constrain because the overall system health is
more important than debugability of a particular application.
A kernel thread has been chosen because we need a reliable way of
invocation so workqueue context is not appropriate because all the
workers might be busy (e.g. allocating memory). Kswapd which sounds
like another good fit is not appropriate as well because it might get
blocked on locks during reclaim as well.
oom_reaper has to take mmap_sem on the target task for reading so the
solution is not 100% because the semaphore might be held or blocked for
write but the probability is reduced considerably wrt. basically any
lock blocking forward progress as described above. In order to prevent
from blocking on the lock without any forward progress we are using only
a trylock and retry 10 times with a short sleep in between. Users of
mmap_sem which need it for write should be carefully reviewed to use
_killable waiting as much as possible and reduce allocations requests
done with the lock held to absolute minimum to reduce the risk even
further.
The API between oom killer and oom reaper is quite trivial.
wake_oom_reaper updates mm_to_reap with cmpxchg to guarantee only
NULL->mm transition and oom_reaper clear this atomically once it is done
with the work. This means that only a single mm_struct can be reaped at
the time. As the operation is potentially disruptive we are trying to
limit it to the ncessary minimum and the reaper blocks any updates while
it operates on an mm. mm_struct is pinned by mm_count to allow parallel
exit_mmap and a race is detected by atomic_inc_not_zero(mm_users).
Signed-off-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Mel Gorman <mgorman@suse.de>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Morton [Fri, 25 Mar 2016 21:20:21 +0000 (14:20 -0700)]
sched: add schedule_timeout_idle()
This will be needed in the patch "mm, oom: introduce oom reaper".
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tony Luck [Fri, 25 Mar 2016 21:37:32 +0000 (14:37 -0700)] 
[IA64] Enable preadv2 and pwritev2 syscalls for ia64
New system calls added in:
f17d8b35452cab31a70d224964cd583fb2845449
vfs: vfs: Define new syscalls preadv2,pwritev2
Signed-off-by: Tony Luck <tony.luck@intel.com>
Rafael J. Wysocki [Fri, 25 Mar 2016 21:33:10 +0000 (22:33 +0100)]
Fix permissions of drivers/power/avs/rockchip-io-domain.c
The permissions of this file were modified by commit (
f447671b9e4f PM /
AVS: rockchip-io: add io selectors and supplies for rk3399) by mistake,
so fix them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Geliang Tang [Sun, 13 Mar 2016 07:18:39 +0000 (15:18 +0800)]
libceph: use KMEM_CACHE macro
Use KMEM_CACHE() instead of kmem_cache_create() to simplify the code.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
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