To make the 5.4-rc1 merge easier, merge at a prerelease point in time
before the final release happens.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I052c6a28528e10cdda89b6a20d320ac7562266b8
Update the default gki_defconfig now that there were some config changes
in mainline.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Iafb8e2fa2d8027b2848e93d2d39b0ea42028289b
To make the 5.4-rc1 merge easier, merge at a prerelease point in time
before the final release happens.
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: If613d657fd0abf9910c5bf3435a745f01b89765e
Allmodconfig on arm64 enables CPU_BIG_ENDIAN=y, which causes issues with
ld.lld which doesn't support linking aarch64be-linux-gnu targets (see
https://reviews.llvm.org/D58655#1410281). However, it is very unlikely
that real android devices run with arm64 BE hardware in practice. So,
until we can find a better fix, let's simply force CPU_BIG_ENDIAN=n for
allmodconfig builds.
Bug: 141733632
Bug: 140224784
Signed-off-by: Quentin Perret <qperret@google.com>
Change-Id: Ic4693ae1f462144c8219b397463ca341f6fe08a1
Add to find_energy_efficient_cpu() a latency sensitive case which mimics
what was done for prefer-idle in android-4.19 and before (see [1] for
reference).
This isn't strictly equivalent to the legacy algorithm but comes real
close, and isn't very invasive. Overall, the idea is to select the
biggest idle CPU we can find for latency-sensitive boosted tasks, and
the smallest CPU where the can fit for latency-sensitive non-boosted
tasks.
The main differences with the legacy behaviour are the following:
1. the policy for 'prefer idle' when there isn't a single idle CPU in
the system is simpler now. We just pick the CPU with the highest
spare capacity;
2. the cstate awareness is implemented by minimizing the exit latency
rather than the idle state index. This is how it is done in the slow
path (find_idlest_group_cpu()), it doesn't require us to keep hooks
into CPUIdle, and should actually be better because what we want is
a CPU that can wake up quickly;
3. non-latency-sensitive tasks just use the standard mainline
energy-aware wake-up path, which decides the placement using the
Energy Model;
4. the 'boosted' and 'latency_sensitive' attributes of a task come from
util_clamp (which now replaces schedtune).
[1] https://android.googlesource.com/kernel/common.git/+/c27c56105dcaaae54ecc39ef33fbfac87a1486fc
Change-Id: Ia58516906e9cb5abe08385a8cd088097043d8703
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Introduce a simple helper to read the latency_sensitive flag from a
task. It is called uclamp_latency_sensitive() to match the API
proposed by Patrick.
While at it, introduce uclamp_boosted() which returns true only when a
task has a non-null min-clamp.
Change-Id: I5fc747da8b58625257a6604a3c88487b657fbe7a
Suggested-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Add a 'latency_sensitive' flag to uclamp in order to express the need
for some tasks to find a CPU where they can wake-up quickly. This is not
expected to be used without cgroup support, so add solely a cgroup
interface for it.
As this flag represents a boolean attribute and not an amount of
resources to be shared, it is not clear what the delegation logic should
be. As such, it is kept simple: every new cgroup starts with
latency_sensitive set to false, regardless of the parent.
In essence, this is similar to SchedTune's prefer-idle flag which was
used in android-4.19 and prior.
Change-Id: I722d8ecabb428bb7b95a5b54bc70a87f182dde2a
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Use schedutil as default cpufreq governor so EAS can start. Also, enable
util-clamp to enable frequency selection biasing.
Change-Id: Iec9098f27c0353dabc23bd98efbca6479de41796
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
If we can classify the group as overloaded, that overrides
any classification as misfit but we may still have misfit
tasks present. Check the rq we're looking at to see if
this is the case.
Change-Id: Ida8eb66aa625e34de3fe2ee1b0dd8a78926273d8
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
[Removed stray reference to rq_has_misfit]
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
When load balancing in a system with misfit tasks present, if we always
pull a misfit task to the local group this can lead to pulling a running
task from a smaller capacity CPUs to a bigger CPU which is busy. In this
situation, the pulled task is likely not to get a chance to run before
an idle balance on another small CPU pulls it back. This penalises the
pulled task as it is stopped for a short amount of time and then likely
relocated to a different CPU (since the original CPU just did a NEWLY_IDLE
balance and reset the periodic interval).
If we only do this unconditionally for NEWLY_IDLE balance, we can be
sure that any tasks and load which are present on the local group are
related to short-running tasks which we are happy to displace for a
longer running task in a system with misfit tasks present.
However, other balance types should only pull a task if we think
that the local group is underutilized - checking the number of tasks
gives us a conservative estimate here since if they were short tasks
we would have been doing NEWLY_IDLE balances instead.
Change-Id: I710add1ab1139482620b6addc8370ad194791beb
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
In some systems the capacity and group weights line up to defeat all the
small imbalance correction conditions in fix_small_imbalance, which can
cause bad task placement. Add a new condition if the existing code can't
see anything to fix:
If we have asymmetric capacity, and there are more tasks than CPUs in
the busiest group *and* there are less tasks than CPUs in the local group
then we try to pull something. There could be transient small tasks which
prevent this from working, but on the whole it is beneficial for those
systems with inconvenient capacity/cluster size relationships.
Change-Id: Icf81cde215c082a61f816534b7990ccb70aee409
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Scenarios with the busiest group having just one task and the local
being idle on topologies with sched groups with different numbers of
cpus manage to dodge all load-balance bailout conditions resulting the
nr_balance_failed counter to be incremented. This eventually causes a
pointless active migration of the task. This patch prevents this by not
incrementing the counter when the busiest group only has one task.
ASYM_PACKING migrations and migrations due to reduced capacity should
still take place as these are explicitly captured by
need_active_balance().
A better solution would be to not attempt the load-balance in the first
place, but that requires significant changes to the order of bailout
conditions and statistics gathering.
Change-Id: I28f69c72febe0211decbe77b7bc3e48839d3d7b3
cc: Ingo Molnar <mingo@redhat.com>
cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Wakeup balancing uses cpu capacity awareness and needs to know the
system-wide maximum cpu capacity.
Patch "sched: Store system-wide maximum cpu capacity in root domain"
finds the system-wide maximum cpu capacity during scheduler domain
hierarchy setup. This is sufficient as long as maximum frequency
invariance is not enabled.
If it is enabled, the system-wide maximum cpu capacity can change
between scheduler domain hierarchy setups due to frequency capping.
The cpu capacity is changed in update_cpu_capacity() which is called in
load balance on the lowest scheduler domain hierarchy level. To be able
to know if a change in cpu capacity for a certain cpu also has an effect
on the system-wide maximum cpu capacity it is normally necessary to
iterate over all cpus. This would be way too costly. That's why this
patch follows a different approach.
The unsigned long max_cpu_capacity value in struct root_domain is
replaced with a struct max_cpu_capacity, containing value (the
max_cpu_capacity) and cpu (the cpu index of the cpu providing the
maximum cpu_capacity).
Changes to the system-wide maximum cpu capacity and the cpu index are
made if:
1 System-wide maximum cpu capacity < cpu capacity
2 System-wide maximum cpu capacity > cpu capacity and cpu index == cpu
There are no changes to the system-wide maximum cpu capacity in all
other cases.
Atomic read and write access to the pair (max_cpu_capacity.val,
max_cpu_capacity.cpu) is enforced by max_cpu_capacity.lock.
The access to max_cpu_capacity.val in task_fits_max() is still performed
without taking the max_cpu_capacity.lock.
The code to set max cpu capacity in build_sched_domains() has been
removed because the whole functionality is now provided by
update_cpu_capacity() instead.
This approach can introduce errors temporarily, e.g. in case the cpu
currently providing the max cpu capacity has its cpu capacity lowered
due to frequency capping and calls update_cpu_capacity() before any cpu
which might provide the max cpu now.
Change-Id: I5063befab088fbf49e5d5e484ce0c6ee6165283a
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>*
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
(- Fixed cherry-pick issues, and conflict with a0fe2cf086 "sched/fair:
Tune down misfit NOHZ kicks" which makes use of max_cpu_capacity
- Squashed "sched/fair: remove printk while schedule is in progress"
fix from Caesar Wang <wxt@rock-chips.com>)
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Implements the Max Frequency Capping Engine (MFCE) getter function
topology_get_max_freq_scale() to provide the scheduler with a
maximum frequency scaling correction factor for more accurate cpu
capacity handling by being able to deal with max frequency capping.
This scaling factor describes the influence of running a cpu with a
current maximum frequency (policy) lower than the maximum possible
frequency (cpuinfo).
The factor is:
policy_max_freq(cpu) << SCHED_CAPACITY_SHIFT / cpuinfo_max_freq(cpu)
It also implements the MFCE setter function arch_set_max_freq_scale()
which is called from cpufreq_set_policy().
Change-Id: I59e52861ee260755ab0518fe1f7183a2e4e3d0fc
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
[Trivial cherry-pick issue in cpufreq.c]
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
To be able to scale the cpu capacity by this factor introduce a call to
the new arch scaling function arch_scale_max_freq_capacity() in
update_cpu_capacity() and provide a default implementation which returns
SCHED_CAPACITY_SCALE.
Another subsystem (e.g. cpufreq) or architectural or platform specific
code can overwrite this default implementation, exactly as for frequency
and cpu invariance. It has to be enabled by the arch by defining
arch_scale_max_freq_capacity to the actual implementation.
Change-Id: I770a8b1f4f7340e9e314f71c64a765bf880f4b4d
Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
( Fixed conflict with scaling against the PELT-based scale_rt_capacity )
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Since we don't do energy-aware wakeups when we are overutilized, always
honoring sync wakeups in this state does not prevent wake-wide mechanics
overruling the flag as normal.
This patch is based upon previous work to build EAS for android products.
sync-hint code taken from commit 4a5e890ec60d
"sched/fair: add tunable to force selection at cpu granularity" written
by Juri Lelli <juri.lelli@arm.com>
Change-Id: I4b3d79141fc8e53dc51cd63ac11096c2e3cb10f5
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
(cherry-picked from commit f1ec666a62dec1083ed52fe1ddef093b84373aaf)
[ Moved the feature to find_energy_efficient_cpu() and removed the
sysctl knob ]
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Utilization clamping can be used to boost the utilization of small tasks
or cap that of big tasks. Thus, one of its possible usages is to bias
tasks placement to "promote" small tasks on higher capacity (less energy
efficient) CPUs or "constraint" big tasks on small capacity (more energy
efficient) CPUs.
When the Energy Aware Scheduler (EAS) looks for the most energy
efficient CPU to run a task on, it currently considers only the
effective utiliation estimated for a task.
Fix this by adding an additional check to skip CPUs which capacity is
smaller then the task clamped utilization.
Change-Id: I43fa6fa27e27c1eb5272c6a45d1a6a5b0faae1aa
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
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Merge tag 'for-5.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A bunch of fixes that accumulated in recent weeks, mostly material for
stable.
Summary:
- fix for regression from 5.3 that prevents to use balance convert
with single profile
- qgroup fixes: rescan race, accounting leak with multiple writers,
potential leak after io failure recovery
- fix for use after free in relocation (reported by KASAN)
- other error handling fixups"
* tag 'for-5.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: qgroup: Fix reserved data space leak if we have multiple reserve calls
btrfs: qgroup: Fix the wrong target io_tree when freeing reserved data space
btrfs: Fix a regression which we can't convert to SINGLE profile
btrfs: relocation: fix use-after-free on dead relocation roots
Btrfs: fix race setting up and completing qgroup rescan workers
Btrfs: fix missing error return if writeback for extent buffer never started
btrfs: adjust dirty_metadata_bytes after writeback failure of extent buffer
Btrfs: fix selftests failure due to uninitialized i_mode in test inodes
A few fixes that have trickled in through the merge window:
- Video fixes for OMAP due to panel-dpi driver removal
- Clock fixes for OMAP that broke no-idle quirks + nfsroot on DRA7
- Fixing arch version on ASpeed ast2500
- Two fixes for reset handling on ARM SCMI
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Merge tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC fixes from Olof Johansson:
"A few fixes that have trickled in through the merge window:
- Video fixes for OMAP due to panel-dpi driver removal
- Clock fixes for OMAP that broke no-idle quirks + nfsroot on DRA7
- Fixing arch version on ASpeed ast2500
- Two fixes for reset handling on ARM SCMI"
* tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
ARM: aspeed: ast2500 is ARMv6K
reset: reset-scmi: add missing handle initialisation
firmware: arm_scmi: reset: fix reset_state assignment in scmi_domain_reset
bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle()
ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux
ARM: dts: am3517-evm: Fix missing video
ARM: dts: logicpd-torpedo-baseboard: Fix missing video
ARM: omap2plus_defconfig: Fix missing video
bus: ti-sysc: Fix handling of invalid clocks
bus: ti-sysc: Fix clock handling for no-idle quirks
- Fixed a buffer overflow by checking nr_args correctly in probes
- Fixed a warning that is reported by clang
- Fixed a possible memory leak in error path of filter processing
- Fixed the selftest that checks for failures, but wasn't failing
- Minor clean up on call site output of a memory trace event
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Merge tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"A few more tracing fixes:
- Fix a buffer overflow by checking nr_args correctly in probes
- Fix a warning that is reported by clang
- Fix a possible memory leak in error path of filter processing
- Fix the selftest that checks for failures, but wasn't failing
- Minor clean up on call site output of a memory trace event"
* tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests/ftrace: Fix same probe error test
mm, tracing: Print symbol name for call_site in trace events
tracing: Have error path in predicate_parse() free its allocated memory
tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
tracing/probe: Fix to check the difference of nr_args before adding probe
Allmodconfig enables as many options as it can to maximize the number of
modules it can build. While this is generally a good idea, this can also
lead to very convoluted configurations (such as CPU_BIG_ENDIAN=y on
arm64) which we don't necessarily want to support even if they break. On
the other hand, gki_defconfig already contains the set of core options
we definitely want to support, so it makes sense to use that as a base.
Point KCONFIG_ALLMODCONFIG to the relevant gki_defconfig file in order
to ensure a minimally sensible config that allconfig is not allowed to
modify.
Bug: 140224784
Signed-off-by: Quentin Perret <qperret@google.com>
Change-Id: Ib4cf3c9565f040a577ce3cec008293520be1af84
The Android Accessory USB gadget functions use core HID functions. As
such, compiling with CONFIG_HID=m and CONFIG_USB_GADGET=y fails to link:
drivers/usb/gadget/function/f_accessory.o: In function `acc_complete_send_hid_event':
f_accessory.c:(.text+0xd54): undefined reference to `hid_report_raw_event'
drivers/usb/gadget/function/f_accessory.o: In function `acc_hid_work':
f_accessory.c:(.text+0x2a98): undefined reference to `hid_destroy_device'
f_accessory.c:(.text+0x2ad4): undefined reference to `hid_allocate_device'
f_accessory.c:(.text+0x2b64): undefined reference to `hid_add_device'
f_accessory.c:(.text+0x2d04): undefined reference to `hid_destroy_device'
drivers/usb/gadget/function/f_accessory.o: In function `acc_hid_parse':
f_accessory.c:(.text+0x2e24): undefined reference to `hid_parse_report'
drivers/usb/gadget/function/f_accessory.o: In function `acc_function_bind_configfs':
f_accessory.c:(.text+0x2f8c): undefined reference to `__hid_register_driver'
drivers/usb/gadget/function/f_accessory.o: In function `acc_function_unbind':
f_accessory.c:(.text+0x3bc8): undefined reference to `hid_unregister_driver'
drivers/usb/gadget/function/f_accessory.o: In function `acc_hid_probe':
f_accessory.c:(.text+0x3ef4): undefined reference to `hid_open_report'
f_accessory.c:(.text+0x3f18): undefined reference to `hid_hw_start'
Fix this by making the dependency on HID explicit.
Bug: 140224784
Fixes: 483cb5629e ("ANDROID: usb: gadget: f_accessory: Add Android
Accessory function")
Signed-off-by: Quentin Perret <qperret@google.com>
Change-Id: Ibd8640d7766cc7802d8275bfe3adfa007f3318fe
Move the static keyword to the front of declaration of
csky_pmu_of_device_ids, and resolve the following compiler
warning that can be seen when building with warnings
enabled (W=1):
arch/csky/kernel/perf_event.c:1340:1: warning:
‘static’ is not at beginning of declaration [-Wold-style-declaration]
Signed-off-by: Krzysztof Wilczynski <kw@linux.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Since the enabling and disabling of IRQs within preempt_schedule_irq()
is contained in a need_resched() loop, we don't need the outer arch
code loop.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Here are 2 small Documentation/process/embargoed-hardware-issues.rst
file updates that missed my previous char/misc pull request for 5.4-rc1.
The first one adds an Intel representative for the process, and the
second one cleans up the text a bit more when it comes to how the
disclosure rules work, as it was a bit confusing to some companies.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull Documentation/process update from Greg KH:
"Here are two small Documentation/process/embargoed-hardware-issues.rst
file updates that missed my previous char/misc pull request.
The first one adds an Intel representative for the process, and the
second one cleans up the text a bit more when it comes to how the
disclosure rules work, as it was a bit confusing to some companies"
* tag 'char-misc-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
Documentation/process: Clarify disclosure rules
Documentation/process: Volunteer as the ambassador for Intel
Pull more vfs updates from Al Viro:
"A couple of misc patches"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
afs dynroot: switch to simple_dir_operations
fs/handle.c - fix up kerneldoc
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Merge tag '5.4-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull more cifs updates from Steve French:
"Fixes from the recent SMB3 Test events and Storage Developer
Conference (held the last two weeks).
Here are nine smb3 patches including an important patch for debugging
traces with wireshark, with three patches marked for stable.
Additional fixes from last week to better handle some newly discovered
reparse points, and a fix the create/mkdir path for setting the mode
more atomically (in SMB3 Create security descriptor context), and one
for path name processing are still being tested so are not included
here"
* tag '5.4-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
CIFS: Fix oplock handling for SMB 2.1+ protocols
smb3: missing ACL related flags
smb3: pass mode bits into create calls
smb3: Add missing reparse tags
CIFS: fix max ea value size
fs/cifs/sess.c: Remove set but not used variable 'capabilities'
fs/cifs/smb2pdu.c: Make SMB2_notify_init static
smb3: fix leak in "open on server" perf counter
smb3: allow decryption keys to be dumped by admin for debugging
The csky_pmu.max_period has type u64, and BIT() can only return
32 bits unsigned long on C-SKY. The initialization for max_period
will be incorrect when count_width is bigger than 32.
Use BIT_ULL()
Signed-off-by: Mao Han <han_mao@c-sky.com>
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
We need set fp zero to let backtrace know the end. The patch fixup perf
callchain panic problem, because backtrace didn't know what is the end
of fp.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reported-by: Mao Han <han_mao@c-sky.com>
The csky implementation of free_initrd_mem() is an open-coded version of
free_reserved_area() without poisoning.
Remove it and make csky use the generic version of free_initrd_mem().
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Guo Ren <guoren@kernel.org>
Merge active entropy generation updates.
This is admittedly partly "for discussion". We need to have a way
forward for the boot time deadlocks where user space ends up waiting for
more entropy, but no entropy is forthcoming because the system is
entirely idle just waiting for something to happen.
While this was triggered by what is arguably a user space bug with
GDM/gnome-session asking for secure randomness during early boot, when
they didn't even need any such truly secure thing, the issue ends up
being that our "getrandom()" interface is prone to that kind of
confusion, because people don't think very hard about whether they want
to block for sufficient amounts of entropy.
The approach here-in is to decide to not just passively wait for entropy
to happen, but to start actively collecting it if it is missing. This
is not necessarily always possible, but if the architecture has a CPU
cycle counter, there is a fair amount of noise in the exact timings of
reasonably complex loads.
We may end up tweaking the load and the entropy estimates, but this
should be at least a reasonable starting point.
As part of this, we also revert the revert of the ext4 IO pattern
improvement that ended up triggering the reported lack of external
entropy.
* getrandom() active entropy waiting:
Revert "Revert "ext4: make __ext4_get_inode_loc plug""
random: try to actively add entropy rather than passively wait for it
This reverts commit 72dbcf7215.
Instead of waiting forever for entropy that may just not happen, we now
try to actively generate entropy when required, and are thus hopefully
avoiding the problem that caused the nice ext4 IO pattern fix to be
reverted.
So revert the revert.
Cc: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Alexander E. Patrakov <patrakov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For 5.3 we had to revert a nice ext4 IO pattern improvement, because it
caused a bootup regression due to lack of entropy at bootup together
with arguably broken user space that was asking for secure random
numbers when it really didn't need to.
See commit 72dbcf7215 (Revert "ext4: make __ext4_get_inode_loc plug").
This aims to solve the issue by actively generating entropy noise using
the CPU cycle counter when waiting for the random number generator to
initialize. This only works when you have a high-frequency time stamp
counter available, but that's the case on all modern x86 CPU's, and on
most other modern CPU's too.
What we do is to generate jitter entropy from the CPU cycle counter
under a somewhat complex load: calling the scheduler while also
guaranteeing a certain amount of timing noise by also triggering a
timer.
I'm sure we can tweak this, and that people will want to look at other
alternatives, but there's been a number of papers written on jitter
entropy, and this should really be fairly conservative by crediting one
bit of entropy for every timer-induced jump in the cycle counter. Not
because the timer itself would be all that unpredictable, but because
the interaction between the timer and the loop is going to be.
Even if (and perhaps particularly if) the timer actually happens on
another CPU, the cacheline interaction between the loop that reads the
cycle counter and the timer itself firing is going to add perturbations
to the cycle counter values that get mixed into the entropy pool.
As Thomas pointed out, with a modern out-of-order CPU, even quite simple
loops show a fair amount of hard-to-predict timing variability even in
the absense of external interrupts. But this tries to take that further
by actually having a fairly complex interaction.
This is not going to solve the entropy issue for architectures that have
no CPU cycle counter, but it's not clear how (and if) that is solvable,
and the hardware in question is largely starting to be irrelevant. And
by doing this we can at least avoid some of the even more contentious
approaches (like making the entropy waiting time out in order to avoid
the possibly unbounded waiting).
Cc: Ahmed Darwish <darwish.07@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Nicholas Mc Guire <hofrat@opentech.at>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Alexander E. Patrakov <patrakov@gmail.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes for omap variants
Few fixes for ti-sysc interconnect target module driver for no-idle
quirks that caused nfsroot to fail on some dra7 boards.
And let's fixes to get LCD working again for logicpd board that got
broken a while back with removal of panel-dpi driver. We need to now
use generic CONFIG_DRM_PANEL_SIMPLE instead.
* tag 'fixes-5.4-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
bus: ti-sysc: Remove unpaired sysc_clkdm_deny_idle()
ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux
ARM: dts: am3517-evm: Fix missing video
ARM: dts: logicpd-torpedo-baseboard: Fix missing video
ARM: omap2plus_defconfig: Fix missing video
bus: ti-sysc: Fix handling of invalid clocks
bus: ti-sysc: Fix clock handling for no-idle quirks
Link: https://lore.kernel.org/r/pull-1568819401-72461@atomide.com
Signed-off-by: Olof Johansson <olof@lixom.net>
Couple of fixes: one in scmi reset driver initialising missed scmi handle
and an other in scmi reset API implementation fixing the assignment of
reset state
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Merge tag 'scmi-fixes-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into arm/fixes
ARM SCMI fixes for v5.4
Couple of fixes: one in scmi reset driver initialising missed scmi handle
and an other in scmi reset API implementation fixing the assignment of
reset state
* tag 'scmi-fixes-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux:
reset: reset-scmi: add missing handle initialisation
firmware: arm_scmi: reset: fix reset_state assignment in scmi_domain_reset
Link: https://lore.kernel.org/r/20190918142139.GA4370@bogus
Signed-off-by: Olof Johansson <olof@lixom.net>
- Complete the reworks to interoperate with powerpc dynamic huge page sizes
- Fix a crash due to missed accounting for the powerpc 'struct
page'-memmap mapping granularity.
- Fix badblock initialization for volatile (DRAM emulated) pmem ranges.
- Stop triggering request_key() notifications to userspace when
NVDIMM-security is disabled / not present.
- Miscellaneous small fixups.
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Merge tag 'libnvdimm-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
More libnvdimm updates from Dan Williams:
- Complete the reworks to interoperate with powerpc dynamic huge page
sizes
- Fix a crash due to missed accounting for the powerpc 'struct
page'-memmap mapping granularity
- Fix badblock initialization for volatile (DRAM emulated) pmem ranges
- Stop triggering request_key() notifications to userspace when
NVDIMM-security is disabled / not present
- Miscellaneous small fixups
* tag 'libnvdimm-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm/region: Enable MAP_SYNC for volatile regions
libnvdimm: prevent nvdimm from requesting key when security is disabled
libnvdimm/region: Initialize bad block for volatile namespaces
libnvdimm/nfit_test: Fix acpi_handle redefinition
libnvdimm/altmap: Track namespace boundaries in altmap
libnvdimm: Fix endian conversion issues
libnvdimm/dax: Pick the right alignment default when creating dax devices
powerpc/book3s64: Export has_transparent_hugepage() related functions.
Pull thermal SoC updates from Eduardo Valentin:
"This is a really small pull in the midst of a lot of pending patches.
We are in the middle of restructuring how we are maintaining the
thermal subsystem, as per discussion in our last LPC. For now, I am
sending just some changes that were pending in my tree. Looking
forward to get a more streamlined process in the next merge window"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
thermal: db8500: Rewrite to be a pure OF sensor
thermal: db8500: Use dev helper variable
thermal: db8500: Finalize device tree conversion
thermal: thermal_mmio: remove some dead code
Pull more i2c updates from Wolfram Sang:
- make Lenovo Yoga C630 boot now that the dependencies are merged
- restore BlockProcessCall for i801, accidently removed in this merge
window
- a bugfix for the riic driver
- an improvement to the slave-eeprom driver which should have been in
the first pull request but sadly got lost in the process
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: slave-eeprom: Add read only mode
i2c: i801: Bring back Block Process Call support for certain platforms
i2c: riic: Clear NACK in tend isr
i2c: qcom-geni: Disable DMA processing on the Lenovo Yoga C630
A couple of fixes for the AMD IOMMU driver have piled up:
* Some fixes for the reworked IO page-table which caused memory
leaks or did not allow to downgrade mappings under some
conditions.
* Locking fixes to fix a couple of possible races around
accessing 'struct protection_domain'. The races got introduced
when the dma-ops path became lock-less in the fast-path.
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Merge tag 'iommu-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu fixes from Joerg Roedel:
"A couple of fixes for the AMD IOMMU driver have piled up:
- Some fixes for the reworked IO page-table which caused memory leaks
or did not allow to downgrade mappings under some conditions.
- Locking fixes to fix a couple of possible races around accessing
'struct protection_domain'. The races got introduced when the
dma-ops path became lock-less in the fast-path"
* tag 'iommu-fixes-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/amd: Lock code paths traversing protection_domain->dev_list
iommu/amd: Lock dev_data in attach/detach code paths
iommu/amd: Check for busy devices earlier in attach_device()
iommu/amd: Take domain->lock for complete attach/detach path
iommu/amd: Remove amd_iommu_devtable_lock
iommu/amd: Remove domain->updated
iommu/amd: Wait for completion of IOTLB flush in attach_device
iommu/amd: Unmap all L7 PTEs when downgrading page-sizes
iommu/amd: Introduce first_pte_l7() helper
iommu/amd: Fix downgrading default page-sizes in alloc_pte()
iommu/amd: Fix pages leak in free_pagetable()
The role of the contact list provided by the disclosing party and how it
affects the disclosure process and the ability to include experts into
the development process is not really well explained.
Neither is it entirely clear when the disclosing party will be informed
about the fact that a developer who is not covered by an employer NDA needs
to be brought in and disclosed.
Explain the role of the contact list and the information policy along with
an eventual conflict resolution better.
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.1909251028390.10825@nanos.tec.linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull networking fixes from David Miller:
1) Sanity check URB networking device parameters to avoid divide by
zero, from Oliver Neukum.
2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6
don't work properly. Longer term this needs a better fix tho. From
Vijay Khemka.
3) Small fixes to selftests (use ping when ping6 is not present, etc.)
from David Ahern.
4) Bring back rt_uses_gateway member of struct rtable, it's semantics
were not well understood and trying to remove it broke things. From
David Ahern.
5) Move usbnet snaity checking, ignore endpoints with invalid
wMaxPacketSize. From Bjørn Mork.
6) Missing Kconfig deps for sja1105 driver, from Mao Wenan.
7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel,
Alex Vesker, and Yevgeny Kliteynik
8) Missing CAP_NET_RAW checks in various places, from Ori Nimron.
9) Fix crash when removing sch_cbs entry while offloading is enabled,
from Vinicius Costa Gomes.
10) Signedness bug fixes, generally in looking at the result given by
of_get_phy_mode() and friends. From Dan Crapenter.
11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet.
12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern.
13) Fix quantization code in tcp_bbr, from Kevin Yang.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits)
net: tap: clean up an indentation issue
nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
sk_buff: drop all skb extensions on free and skb scrubbing
tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions
Documentation: Clarify trap's description
mlxsw: spectrum: Clear VLAN filters during port initialization
net: ena: clean up indentation issue
NFC: st95hf: clean up indentation issue
net: phy: micrel: add Asym Pause workaround for KSZ9021
net: socionext: ave: Avoid using netdev_err() before calling register_netdev()
ptp: correctly disable flags on old ioctls
lib: dimlib: fix help text typos
net: dsa: microchip: Always set regmap stride to 1
nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs
nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs
net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N
vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled
net: sched: sch_sfb: don't call qdisc_put() while holding tree lock
...
Merge hugepage allocation updates from David Rientjes:
"We (mostly Linus, Andrea, and myself) have been discussing offlist how
to implement a sane default allocation strategy for hugepages on NUMA
platforms.
With these reverts in place, the page allocator will happily allocate
a remote hugepage immediately rather than try to make a local hugepage
available. This incurs a substantial performance degradation when
memory compaction would have otherwise made a local hugepage
available.
This series reverts those reverts and attempts to propose a more sane
default allocation strategy specifically for hugepages. Andrea
acknowledges this is likely to fix the swap storms that he originally
reported that resulted in the patches that removed __GFP_THISNODE from
hugepage allocations.
The immediate goal is to return 5.3 to the behavior the kernel has
implemented over the past several years so that remote hugepages are
not immediately allocated when local hugepages could have been made
available because the increased access latency is untenable.
The next goal is to introduce a sane default allocation strategy for
hugepages allocations in general regardless of the configuration of
the system so that we prevent thrashing of local memory when
compaction is unlikely to succeed and can prefer remote hugepages over
remote native pages when the local node is low on memory."
Note on timing: this reverts the hugepage VM behavior changes that got
introduced fairly late in the 5.3 cycle, and that fixed a huge
performance regression for certain loads that had been around since
4.18.
Andrea had this note:
"The regression of 4.18 was that it was taking hours to start a VM
where 3.10 was only taking a few seconds, I reported all the details
on lkml when it was finally tracked down in August 2018.
https://lore.kernel.org/linux-mm/20180820032640.9896-2-aarcange@redhat.com/
__GFP_THISNODE in MADV_HUGEPAGE made the above enterprise vfio
workload degrade like in the "current upstream" above. And it still
would have been that bad as above until 5.3-rc5"
where the bad behavior ends up happening as you fill up a local node,
and without that change, you'd get into the nasty swap storm behavior
due to compaction working overtime to make room for more memory on the
nodes.
As a result 5.3 got the two performance fix reverts in rc5.
However, David Rientjes then noted that those performance fixes in turn
regressed performance for other loads - although not quite to the same
degree. He suggested reverting the reverts and instead replacing them
with two small changes to how hugepage allocations are done (patch
descriptions rephrased by me):
- "avoid expensive reclaim when compaction may not succeed": just admit
that the allocation failed when you're trying to allocate a huge-page
and compaction wasn't successful.
- "allow hugepage fallback to remote nodes when madvised": when that
node-local huge-page allocation failed, retry without forcing the
local node.
but by then I judged it too late to replace the fixes for a 5.3 release.
So 5.3 was released with behavior that harked back to the pre-4.18 logic.
But now we're in the merge window for 5.4, and we can see if this
alternate model fixes not just the horrendous swap storm behavior, but
also restores the performance regression that the late reverts caused.
Fingers crossed.
* emailed patches from David Rientjes <rientjes@google.com>:
mm, page_alloc: allow hugepage fallback to remote nodes when madvised
mm, page_alloc: avoid expensive reclaim when compaction may not succeed
Revert "Revert "Revert "mm, thp: consolidate THP gfp handling into alloc_hugepage_direct_gfpmask""
Revert "Revert "mm, thp: restore node-local hugepage allocations""
