The function get_loadavg() returns almost always zero. To be more
precise, statistically speaking for a total of 1023379 times passing
in the function, the load is equal to zero 1020728 times, greater than
100, 610 times, the remaining is between 0 and 5.
In 2011, the get_loadavg() was removed from the Android tree because
of the above [1]. At this time, the load was:
unsigned long this_cpu_load(void)
{
struct rq *this = this_rq();
return this->cpu_load[0];
}
In 2014, the code was changed by commit 372ba8cb46 (cpuidle: menu: Lookup CPU
runqueues less) and the load is:
void get_iowait_load(unsigned long *nr_waiters, unsigned long *load)
{
struct rq *rq = this_rq();
*nr_waiters = atomic_read(&rq->nr_iowait);
*load = rq->load.weight;
}
with the same result.
Both measurements show using the load in this code path does no matter
anymore. Removing it.
[1] 4dedd9f124
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function nr_iowait_cpu() can be used directly by nr_iowait() instead
of duplicating code.
Call nr_iowait_cpu() from nr_iowait()
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull security subsystem updates from James Morris:
"In this patchset, there are a couple of minor updates, as well as some
reworking of the LSM initialization code from Kees Cook (these prepare
the way for ordered stackable LSMs, but are a valuable cleanup on
their own)"
* 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
LSM: Don't ignore initialization failures
LSM: Provide init debugging infrastructure
LSM: Record LSM name in struct lsm_info
LSM: Convert security_initcall() into DEFINE_LSM()
vmlinux.lds.h: Move LSM_TABLE into INIT_DATA
LSM: Convert from initcall to struct lsm_info
LSM: Remove initcall tracing
LSM: Rename .security_initcall section to .lsm_info
vmlinux.lds.h: Avoid copy/paste of security_init section
LSM: Correctly announce start of LSM initialization
security: fix LSM description location
keys: Fix the use of the C++ keyword "private" in uapi/linux/keyctl.h
seccomp: remove unnecessary unlikely()
security: tomoyo: Fix obsolete function
security/capabilities: remove check for -EINVAL
Pull siginfo updates from Eric Biederman:
"I have been slowly sorting out siginfo and this is the culmination of
that work.
The primary result is in several ways the signal infrastructure has
been made less error prone. The code has been updated so that manually
specifying SEND_SIG_FORCED is never necessary. The conversion to the
new siginfo sending functions is now complete, which makes it
difficult to send a signal without filling in the proper siginfo
fields.
At the tail end of the patchset comes the optimization of decreasing
the size of struct siginfo in the kernel from 128 bytes to about 48
bytes on 64bit. The fundamental observation that enables this is by
definition none of the known ways to use struct siginfo uses the extra
bytes.
This comes at the cost of a small user space observable difference.
For the rare case of siginfo being injected into the kernel only what
can be copied into kernel_siginfo is delivered to the destination, the
rest of the bytes are set to 0. For cases where the signal and the
si_code are known this is safe, because we know those bytes are not
used. For cases where the signal and si_code combination is unknown
the bits that won't fit into struct kernel_siginfo are tested to
verify they are zero, and the send fails if they are not.
I made an extensive search through userspace code and I could not find
anything that would break because of the above change. If it turns out
I did break something it will take just the revert of a single change
to restore kernel_siginfo to the same size as userspace siginfo.
Testing did reveal dependencies on preferring the signo passed to
sigqueueinfo over si->signo, so bit the bullet and added the
complexity necessary to handle that case.
Testing also revealed bad things can happen if a negative signal
number is passed into the system calls. Something no sane application
will do but something a malicious program or a fuzzer might do. So I
have fixed the code that performs the bounds checks to ensure negative
signal numbers are handled"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits)
signal: Guard against negative signal numbers in copy_siginfo_from_user32
signal: Guard against negative signal numbers in copy_siginfo_from_user
signal: In sigqueueinfo prefer sig not si_signo
signal: Use a smaller struct siginfo in the kernel
signal: Distinguish between kernel_siginfo and siginfo
signal: Introduce copy_siginfo_from_user and use it's return value
signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
signal: Fail sigqueueinfo if si_signo != sig
signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
signal/unicore32: Use force_sig_fault where appropriate
signal/unicore32: Generate siginfo in ucs32_notify_die
signal/unicore32: Use send_sig_fault where appropriate
signal/arc: Use force_sig_fault where appropriate
signal/arc: Push siginfo generation into unhandled_exception
signal/ia64: Use force_sig_fault where appropriate
signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
signal/ia64: Use the generic force_sigsegv in setup_frame
signal/arm/kvm: Use send_sig_mceerr
signal/arm: Use send_sig_fault where appropriate
signal/arm: Use force_sig_fault where appropriate
...
Pull networking updates from David Miller:
1) Add VF IPSEC offload support in ixgbe, from Shannon Nelson.
2) Add zero-copy AF_XDP support to i40e, from Björn Töpel.
3) All in-tree drivers are converted to {g,s}et_link_ksettings() so we
can get rid of the {g,s}et_settings ethtool callbacks, from Michal
Kubecek.
4) Add software timestamping to veth driver, from Michael Walle.
5) More work to make packet classifiers and actions lockless, from Vlad
Buslov.
6) Support sticky FDB entries in bridge, from Nikolay Aleksandrov.
7) Add ipv6 version of IP_MULTICAST_ALL sockopt, from Andre Naujoks.
8) Support batching of XDP buffers in vhost_net, from Jason Wang.
9) Add flow dissector BPF hook, from Petar Penkov.
10) i40e vf --> generic iavf conversion, from Jesse Brandeburg.
11) Add NLA_REJECT netlink attribute policy type, to signal when users
provide attributes in situations which don't make sense. From
Johannes Berg.
12) Switch TCP and fair-queue scheduler over to earliest departure time
model. From Eric Dumazet.
13) Improve guest receive performance by doing rx busy polling in tx
path of vhost networking driver, from Tonghao Zhang.
14) Add per-cgroup local storage to bpf
15) Add reference tracking to BPF, from Joe Stringer. The verifier can
now make sure that references taken to objects are properly released
by the program.
16) Support in-place encryption in TLS, from Vakul Garg.
17) Add new taprio packet scheduler, from Vinicius Costa Gomes.
18) Lots of selftests additions, too numerous to mention one by one here
but all of which are very much appreciated.
19) Support offloading of eBPF programs containing BPF to BPF calls in
nfp driver, frm Quentin Monnet.
20) Move dpaa2_ptp driver out of staging, from Yangbo Lu.
21) Lots of u32 classifier cleanups and simplifications, from Al Viro.
22) Add new strict versions of netlink message parsers, and enable them
for some situations. From David Ahern.
23) Evict neighbour entries on carrier down, also from David Ahern.
24) Support BPF sk_msg verdict programs with kTLS, from Daniel Borkmann
and John Fastabend.
25) Add support for filtering route dumps, from David Ahern.
26) New igc Intel driver for 2.5G parts, from Sasha Neftin et al.
27) Allow vxlan enslavement to bridges in mlxsw driver, from Ido
Schimmel.
28) Add queue and stack map types to eBPF, from Mauricio Vasquez B.
29) Add back byte-queue-limit support to r8169, with all the bug fixes
in other areas of the driver it works now! From Florian Westphal and
Heiner Kallweit.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2147 commits)
tcp: add tcp_reset_xmit_timer() helper
qed: Fix static checker warning
Revert "be2net: remove desc field from be_eq_obj"
Revert "net: simplify sock_poll_wait"
net: socionext: Reset tx queue in ndo_stop
net: socionext: Add dummy PHY register read in phy_write()
net: socionext: Stop PHY before resetting netsec
net: stmmac: Set OWN bit for jumbo frames
arm64: dts: stratix10: Support Ethernet Jumbo frame
tls: Add maintainers
net: ethernet: ti: cpsw: unsync mcast entries while switch promisc mode
octeontx2-af: Support for NIXLF's UCAST/PROMISC/ALLMULTI modes
octeontx2-af: Support for setting MAC address
octeontx2-af: Support for changing RSS algorithm
octeontx2-af: NIX Rx flowkey configuration for RSS
octeontx2-af: Install ucast and bcast pkt forwarding rules
octeontx2-af: Add LMAC channel info to NIXLF_ALLOC response
octeontx2-af: NPC MCAM and LDATA extract minimal configuration
octeontx2-af: Enable packet length and csum validation
octeontx2-af: Support for VTAG strip and capture
...
Pull x86 vdso updates from Ingo Molnar:
"Two main changes:
- Cleanups, simplifications and CLOCK_TAI support (Thomas Gleixner)
- Improve code generation (Andy Lutomirski)"
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vdso: Rearrange do_hres() to improve code generation
x86/vdso: Document vgtod_ts better
x86/vdso: Remove "memory" clobbers in the vDSO syscall fallbacks
x66/vdso: Add CLOCK_TAI support
x86/vdso: Move cycle_last handling into the caller
x86/vdso: Simplify the invalid vclock case
x86/vdso: Replace the clockid switch case
x86/vdso: Collapse coarse functions
x86/vdso: Collapse high resolution functions
x86/vdso: Introduce and use vgtod_ts
x86/vdso: Use unsigned int consistently for vsyscall_gtod_data:: Seq
x86/vdso: Enforce 64bit clocksource
x86/time: Implement clocksource_arch_init()
clocksource: Provide clocksource_arch_init()
Pull x86 pti updates from Ingo Molnar:
"The main changes:
- Make the IBPB barrier more strict and add STIBP support (Jiri
Kosina)
- Micro-optimize and clean up the entry code (Andy Lutomirski)
- ... plus misc other fixes"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation: Propagate information about RSB filling mitigation to sysfs
x86/speculation: Enable cross-hyperthread spectre v2 STIBP mitigation
x86/speculation: Apply IBPB more strictly to avoid cross-process data leak
x86/speculation: Add RETPOLINE_AMD support to the inline asm CALL_NOSPEC variant
x86/CPU: Fix unused variable warning when !CONFIG_IA32_EMULATION
x86/pti/64: Remove the SYSCALL64 entry trampoline
x86/entry/64: Use the TSS sp2 slot for SYSCALL/SYSRET scratch space
x86/entry/64: Document idtentry
Pull x86 mm updates from Ingo Molnar:
"Lots of changes in this cycle:
- Lots of CPA (change page attribute) optimizations and related
cleanups (Thomas Gleixner, Peter Zijstra)
- Make lazy TLB mode even lazier (Rik van Riel)
- Fault handler cleanups and improvements (Dave Hansen)
- kdump, vmcore: Enable kdumping encrypted memory with AMD SME
enabled (Lianbo Jiang)
- Clean up VM layout documentation (Baoquan He, Ingo Molnar)
- ... plus misc other fixes and enhancements"
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
x86/stackprotector: Remove the call to boot_init_stack_canary() from cpu_startup_entry()
x86/mm: Kill stray kernel fault handling comment
x86/mm: Do not warn about PCI BIOS W+X mappings
resource: Clean it up a bit
resource: Fix find_next_iomem_res() iteration issue
resource: Include resource end in walk_*() interfaces
x86/kexec: Correct KEXEC_BACKUP_SRC_END off-by-one error
x86/mm: Remove spurious fault pkey check
x86/mm/vsyscall: Consider vsyscall page part of user address space
x86/mm: Add vsyscall address helper
x86/mm: Fix exception table comments
x86/mm: Add clarifying comments for user addr space
x86/mm: Break out user address space handling
x86/mm: Break out kernel address space handling
x86/mm: Clarify hardware vs. software "error_code"
x86/mm/tlb: Make lazy TLB mode lazier
x86/mm/tlb: Add freed_tables element to flush_tlb_info
x86/mm/tlb: Add freed_tables argument to flush_tlb_mm_range
smp,cpumask: introduce on_each_cpu_cond_mask
smp: use __cpumask_set_cpu in on_each_cpu_cond
...
Pull x86 apic updates from Ingo Molnar:
"Improve the spreading of managed IRQs at allocation time"
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq/matrix: Spread managed interrupts on allocation
irq/matrix: Split out the CPU selection code into a helper
Pull scheduler updates from Ingo Molnar:
"The main changes are:
- Migrate CPU-intense 'misfit' tasks on asymmetric capacity systems,
to better utilize (much) faster 'big core' CPUs. (Morten Rasmussen,
Valentin Schneider)
- Topology handling improvements, in particular when CPU capacity
changes and related load-balancing fixes/improvements (Morten
Rasmussen)
- ... plus misc other improvements, fixes and updates"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
sched/completions/Documentation: Add recommendation for dynamic and ONSTACK completions
sched/completions/Documentation: Clean up the document some more
sched/completions/Documentation: Fix a couple of punctuation nits
cpu/SMT: State SMT is disabled even with nosmt and without "=force"
sched/core: Fix comment regarding nr_iowait_cpu() and get_iowait_load()
sched/fair: Remove setting task's se->runnable_weight during PELT update
sched/fair: Disable LB_BIAS by default
sched/pelt: Fix warning and clean up IRQ PELT config
sched/topology: Make local variables static
sched/debug: Use symbolic names for task state constants
sched/numa: Remove unused numa_stats::nr_running field
sched/numa: Remove unused code from update_numa_stats()
sched/debug: Explicitly cast sched_feat() to bool
sched/core: Disable SD_PREFER_SIBLING on asymmetric CPU capacity domains
sched/fair: Don't move tasks to lower capacity CPUs unless necessary
sched/fair: Set rq->rd->overload when misfit
sched/fair: Wrap rq->rd->overload accesses with READ/WRITE_ONCE()
sched/core: Change root_domain->overload type to int
sched/fair: Change 'prefer_sibling' type to bool
sched/fair: Kick nohz balance if rq->misfit_task_load
...
Pull perf updates from Ingo Molnar:
"The main updates in this cycle were:
- Lots of perf tooling changes too voluminous to list (big perf trace
and perf stat improvements, lots of libtraceevent reorganization,
etc.), so I'll list the authors and refer to the changelog for
details:
Benjamin Peterson, Jérémie Galarneau, Kim Phillips, Peter
Zijlstra, Ravi Bangoria, Sangwon Hong, Sean V Kelley, Steven
Rostedt, Thomas Gleixner, Ding Xiang, Eduardo Habkost, Thomas
Richter, Andi Kleen, Sanskriti Sharma, Adrian Hunter, Tzvetomir
Stoyanov, Arnaldo Carvalho de Melo, Jiri Olsa.
... with the bulk of the changes written by Jiri Olsa, Tzvetomir
Stoyanov and Arnaldo Carvalho de Melo.
- Continued intel_rdt work with a focus on playing well with perf
events. This also imported some non-perf RDT work due to
dependencies. (Reinette Chatre)
- Implement counter freezing for Arch Perfmon v4 (Skylake and newer).
This allows to speed up the PMI handler by avoiding unnecessary MSR
writes and make it more accurate. (Andi Kleen)
- kprobes cleanups and simplification (Masami Hiramatsu)
- Intel Goldmont PMU updates (Kan Liang)
- ... plus misc other fixes and updates"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (155 commits)
kprobes/x86: Use preempt_enable() in optimized_callback()
x86/intel_rdt: Prevent pseudo-locking from using stale pointers
kprobes, x86/ptrace.h: Make regs_get_kernel_stack_nth() not fault on bad stack
perf/x86/intel: Export mem events only if there's PEBS support
x86/cpu: Drop pointless static qualifier in punit_dev_state_show()
x86/intel_rdt: Fix initial allocation to consider CDP
x86/intel_rdt: CBM overlap should also check for overlap with CDP peer
x86/intel_rdt: Introduce utility to obtain CDP peer
tools lib traceevent, perf tools: Move struct tep_handler definition in a local header file
tools lib traceevent: Separate out tep_strerror() for strerror_r() issues
perf python: More portable way to make CFLAGS work with clang
perf python: Make clang_has_option() work on Python 3
perf tools: Free temporary 'sys' string in read_event_files()
perf tools: Avoid double free in read_event_file()
perf tools: Free 'printk' string in parse_ftrace_printk()
perf tools: Cleanup trace-event-info 'tdata' leak
perf strbuf: Match va_{add,copy} with va_end
perf test: S390 does not support watchpoints in test 22
perf auxtrace: Include missing asm/bitsperlong.h to get BITS_PER_LONG
tools include: Adopt linux/bits.h
...
Pull locking and misc x86 updates from Ingo Molnar:
"Lots of changes in this cycle - in part because locking/core attracted
a number of related x86 low level work which was easier to handle in a
single tree:
- Linux Kernel Memory Consistency Model updates (Alan Stern, Paul E.
McKenney, Andrea Parri)
- lockdep scalability improvements and micro-optimizations (Waiman
Long)
- rwsem improvements (Waiman Long)
- spinlock micro-optimization (Matthew Wilcox)
- qspinlocks: Provide a liveness guarantee (more fairness) on x86.
(Peter Zijlstra)
- Add support for relative references in jump tables on arm64, x86
and s390 to optimize jump labels (Ard Biesheuvel, Heiko Carstens)
- Be a lot less permissive on weird (kernel address) uaccess faults
on x86: BUG() when uaccess helpers fault on kernel addresses (Jann
Horn)
- macrofy x86 asm statements to un-confuse the GCC inliner. (Nadav
Amit)
- ... and a handful of other smaller changes as well"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
locking/lockdep: Make global debug_locks* variables read-mostly
locking/lockdep: Fix debug_locks off performance problem
locking/pvqspinlock: Extend node size when pvqspinlock is configured
locking/qspinlock_stat: Count instances of nested lock slowpaths
locking/qspinlock, x86: Provide liveness guarantee
x86/asm: 'Simplify' GEN_*_RMWcc() macros
locking/qspinlock: Rework some comments
locking/qspinlock: Re-order code
locking/lockdep: Remove duplicated 'lock_class_ops' percpu array
x86/defconfig: Enable CONFIG_USB_XHCI_HCD=y
futex: Replace spin_is_locked() with lockdep
locking/lockdep: Make class->ops a percpu counter and move it under CONFIG_DEBUG_LOCKDEP=y
x86/jump-labels: Macrofy inline assembly code to work around GCC inlining bugs
x86/cpufeature: Macrofy inline assembly code to work around GCC inlining bugs
x86/extable: Macrofy inline assembly code to work around GCC inlining bugs
x86/paravirt: Work around GCC inlining bugs when compiling paravirt ops
x86/bug: Macrofy the BUG table section handling, to work around GCC inlining bugs
x86/alternatives: Macrofy lock prefixes to work around GCC inlining bugs
x86/refcount: Work around GCC inlining bug
x86/objtool: Use asm macros to work around GCC inlining bugs
...
Pull RCU updates from Ingo Molnar:
"The biggest change in this cycle is the conclusion of the big
'simplify RCU to two primary flavors' consolidation work - i.e.
there's a single RCU flavor for any kernel variant (PREEMPT and
!PREEMPT):
- Consolidate the RCU-bh, RCU-preempt, and RCU-sched flavors into a
single flavor similar to RCU-sched in !PREEMPT kernels and into a
single flavor similar to RCU-preempt (but also waiting on
preempt-disabled sequences of code) in PREEMPT kernels.
This branch also includes a refactoring of
rcu_{nmi,irq}_{enter,exit}() from Byungchul Park.
- Now that there is only one RCU flavor in any given running kernel,
the many "rsp" pointers are no longer required, and this cleanup
series removes them.
- This branch carries out additional cleanups made possible by the
RCU flavor consolidation, including inlining now-trivial
functions, updating comments and definitions, and removing
now-unneeded rcutorture scenarios.
- Now that there is only one flavor of RCU in any running kernel,
there is also only on rcu_data structure per CPU. This means that
the rcu_dynticks structure can be merged into the rcu_data
structure, a task taken on by this branch. This branch also
contains a -rt-related fix from Mike Galbraith.
There were also other updates:
- Documentation updates, including some good-eye catches from Joel
Fernandes.
- SRCU updates, most notably changes enabling call_srcu() to be
invoked very early in the boot sequence.
- Torture-test updates, including some preliminary work towards
making rcutorture better able to find problems that result in
insufficient grace-period forward progress.
- Initial changes to RCU to better promote forward progress of grace
periods, including fixing a bug found by Marius Hillenbrand and
David Woodhouse, with the fix suggested by Peter Zijlstra"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (140 commits)
srcu: Make early-boot call_srcu() reuse workqueue lists
rcutorture: Test early boot call_srcu()
srcu: Make call_srcu() available during very early boot
rcu: Convert rcu_state.ofl_lock to raw_spinlock_t
rcu: Remove obsolete ->dynticks_fqs and ->cond_resched_completed
rcu: Switch ->dynticks to rcu_data structure, remove rcu_dynticks
rcu: Switch dyntick nesting counters to rcu_data structure
rcu: Switch urgent quiescent-state requests to rcu_data structure
rcu: Switch lazy counts to rcu_data structure
rcu: Switch last accelerate/advance to rcu_data structure
rcu: Switch ->tick_nohz_enabled_snap to rcu_data structure
rcu: Merge rcu_dynticks structure into rcu_data structure
rcu: Remove unused rcu_dynticks_snap() from Tiny RCU
rcu: Convert "1UL << x" to "BIT(x)"
rcu: Avoid resched_cpu() when rescheduling the current CPU
rcu: More aggressively enlist scheduler aid for nohz_full CPUs
rcu: Compute jiffies_till_sched_qs from other kernel parameters
rcu: Provide functions for determining if call_rcu() has been invoked
rcu: Eliminate ->rcu_qs_ctr from the rcu_dynticks structure
rcu: Motivate Tiny RCU forward progress
...
- Backport hibernation bug fixes from x86-64 to x86-32 and
consolidate hibernation handling on x86 to allow 32-bit
systems to work in all of the cases in which 64-bit ones
work (Zhimin Gu, Chen Yu).
- Fix hibernation documentation (Vladimir D. Seleznev).
- Update the menu cpuidle governor to fix a couple of issues
with it, make it more efficient in some cases and clean it
up (Rafael Wysocki).
- Rework the cpuidle polling state implementation to make it
more efficient (Rafael Wysocki).
- Clean up the cpuidle core somewhat (Fieah Lim).
- Fix the cpufreq conservative governor to take policy limits
into account properly in some cases (Rafael Wysocki).
- Add support for retrieving guaranteed performance information
to the ACPI CPPC library and make the intel_pstate driver use
it to expose the CPU base frequency via sysfs on systems with
the hardware-managed P-states (HWP) feature enabled (Srinivas
Pandruvada).
- Fix clang warning in the CPPC cpufreq driver (Nathan Chancellor).
- Get rid of device_node.name printing from cpufreq (Rob Herring).
- Remove unnecessary unlikely() from the cpufreq core (Igor Stoppa).
- Add support for the r8a7744 SoC to the cpufreq-dt driver (Biju Das).
- Update the dt-platdev cpufreq driver to allow RK3399 to have
separate tunables per cluster (Dmitry Torokhov).
- Fix the dma_alloc_coherent() usage in the tegra186 cpufreq driver
(Christoph Hellwig).
- Make the imx6q cpufreq driver read OCOTP through nvmem for
imx6ul/imx6ull (Anson Huang).
- Fix several bugs in the operating performance points (OPP)
framework and make it more stable (Viresh Kumar, Dave Gerlach).
- Update the devfreq subsystem to take changes in the APIs used
by into account, fix some issues with it and make it stop
print device_node.name directly (Bjorn Andersson, Enric Balletbo
i Serra, Matthias Kaehlcke, Rob Herring, Vincent Donnefort, zhong
jiang).
- Prepare the generic power domains (genpd) framework for dealing
with domains containing CPUs (Ulf Hansson).
- Prevent sysfs attributes representing low-power S0 residency
counters from being exposed if low-power S0 support is not
indicated in ACPI FADT (Rajneesh Bhardwaj).
- Get rid of custom CPU features macros for Intel CPUs from the
intel_idle and RAPL drivers (Andy Shevchenko).
- Update the tasks freezer to list tasks that refused to freeze
and caused a system transition to a sleep state to be aborted
(Todd Brandt).
- Update the pm-graph set of tools to v5.2 (Todd Brandt).
- Fix some issues in the cpupower utility (Anders Roxell, Prarit
Bhargava).
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Merge tag 'pm-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These make hibernation on 32-bit x86 systems work in all of the cases
in which it works on 64-bit x86 ones, update the menu cpuidle governor
and the "polling" state to make them more efficient, add more hardware
support to cpufreq drivers and fix issues with some of them, fix a bug
in the conservative cpufreq governor, fix the operating performance
points (OPP) framework and make it more stable, update the devfreq
subsystem to take changes in the APIs used by into account and clean
up some things all over.
Specifics:
- Backport hibernation bug fixes from x86-64 to x86-32 and
consolidate hibernation handling on x86 to allow 32-bit systems to
work in all of the cases in which 64-bit ones work (Zhimin Gu, Chen
Yu).
- Fix hibernation documentation (Vladimir D. Seleznev).
- Update the menu cpuidle governor to fix a couple of issues with it,
make it more efficient in some cases and clean it up (Rafael
Wysocki).
- Rework the cpuidle polling state implementation to make it more
efficient (Rafael Wysocki).
- Clean up the cpuidle core somewhat (Fieah Lim).
- Fix the cpufreq conservative governor to take policy limits into
account properly in some cases (Rafael Wysocki).
- Add support for retrieving guaranteed performance information to
the ACPI CPPC library and make the intel_pstate driver use it to
expose the CPU base frequency via sysfs on systems with the
hardware-managed P-states (HWP) feature enabled (Srinivas
Pandruvada).
- Fix clang warning in the CPPC cpufreq driver (Nathan Chancellor).
- Get rid of device_node.name printing from cpufreq (Rob Herring).
- Remove unnecessary unlikely() from the cpufreq core (Igor Stoppa).
- Add support for the r8a7744 SoC to the cpufreq-dt driver (Biju
Das).
- Update the dt-platdev cpufreq driver to allow RK3399 to have
separate tunables per cluster (Dmitry Torokhov).
- Fix the dma_alloc_coherent() usage in the tegra186 cpufreq driver
(Christoph Hellwig).
- Make the imx6q cpufreq driver read OCOTP through nvmem for
imx6ul/imx6ull (Anson Huang).
- Fix several bugs in the operating performance points (OPP)
framework and make it more stable (Viresh Kumar, Dave Gerlach).
- Update the devfreq subsystem to take changes in the APIs used by
into account, fix some issues with it and make it stop print
device_node.name directly (Bjorn Andersson, Enric Balletbo i Serra,
Matthias Kaehlcke, Rob Herring, Vincent Donnefort, zhong jiang).
- Prepare the generic power domains (genpd) framework for dealing
with domains containing CPUs (Ulf Hansson).
- Prevent sysfs attributes representing low-power S0 residency
counters from being exposed if low-power S0 support is not
indicated in ACPI FADT (Rajneesh Bhardwaj).
- Get rid of custom CPU features macros for Intel CPUs from the
intel_idle and RAPL drivers (Andy Shevchenko).
- Update the tasks freezer to list tasks that refused to freeze and
caused a system transition to a sleep state to be aborted (Todd
Brandt).
- Update the pm-graph set of tools to v5.2 (Todd Brandt).
- Fix some issues in the cpupower utility (Anders Roxell, Prarit
Bhargava)"
* tag 'pm-4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (73 commits)
PM / Domains: Document flags for genpd
PM / Domains: Deal with multiple states but no governor in genpd
PM / Domains: Don't treat zero found compatible idle states as an error
cpuidle: menu: Avoid computations when result will be discarded
cpuidle: menu: Drop redundant comparison
cpufreq: tegra186: don't pass GFP_DMA32 to dma_alloc_coherent()
cpufreq: conservative: Take limits changes into account properly
Documentation: intel_pstate: Add base_frequency information
cpufreq: intel_pstate: Add base_frequency attribute
ACPI / CPPC: Add support for guaranteed performance
cpuidle: menu: Simplify checks related to the polling state
PM / tools: sleepgraph and bootgraph: upgrade to v5.2
PM / tools: sleepgraph: first batch of v5.2 changes
cpupower: Fix coredump on VMWare
cpupower: Fix AMD Family 0x17 msr_pstate size
cpufreq: imx6q: read OCOTP through nvmem for imx6ul/imx6ull
cpufreq: dt-platdev: allow RK3399 to have separate tunables per cluster
cpuidle: poll_state: Revise loop termination condition
cpuidle: menu: Move the latency_req == 0 special case check
cpuidle: menu: Avoid computations for very close timers
...
User mode helpers were spawned without a command line, and because
an empty command line is used by many tools to identify processes as
kernel threads, this could cause some issues.
Notably during killing spree on shutdown, since such helper would then
be skipped (i.e. not killed) which would result in the process remaining
alive, and thus preventing unmouting of the rootfs (as experienced with
the bpfilter umh).
Fixes: 449325b52b ("umh: introduce fork_usermode_blob() helper")
Signed-off-by: Olivier Brunel <jjk@jjacky.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The biggest chunk of the regulator changes for this release outside of
the new drivers is the conversion of the fixed regulator to use the GPIO
descriptor API, there's a small addition to the GPIO API plus a bunch of
updates to board files to implement it. This is some really welcome
work from Linus Walleij that's had a bunch of review and has been
sitting in -next for a while so I'm fairly happy there's no major
issues.
- Helpers for overlapping linear ranges.
- Display opmode and consumer requested load in the regualtor_summary
file in debugfs, plus a fix there.
- Support for the fun and entertaining power off mechanism that the
pfuze100 hardware implements.
- Conversion of the fixed regulator API to use GPIO descriptors,
including pulling in a bunch of patches to a bunch of board files.
- New drivers for Cirrus Logic Lochnagar, Qualcomm PMS405, Rohm
BD71847, ST PMIC1, and TI LM363x devices.
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Merge tag 'regulator-v5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator updates from Mark Brown:
"The biggest chunk of the regulator changes for this release outside of
the new drivers is the conversion of the fixed regulator to use the
GPIO descriptor API, there's a small addition to the GPIO API plus a
bunch of updates to board files to implement it. This is some really
welcome work from Linus Walleij that's had a bunch of review and has
been sitting in -next for a while so I'm fairly happy there's no major
issues.
- Helpers for overlapping linear ranges.
- Display opmode and consumer requested load in the regualtor_summary
file in debugfs, plus a fix there.
- Support for the fun and entertaining power off mechanism that the
pfuze100 hardware implements.
- Conversion of the fixed regulator API to use GPIO descriptors,
including pulling in a bunch of patches to a bunch of board files.
- New drivers for Cirrus Logic Lochnagar, Qualcomm PMS405, Rohm
BD71847, ST PMIC1, and TI LM363x devices"
* tag 'regulator-v5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (36 commits)
regulator: lochnagar: Use a consisent comment style for SPDX header
regulator: bd718x7: Remove struct bd718xx_pmic
regulator: Fetch enable gpiods nonexclusive
regulator/gpio: Allow nonexclusive GPIO access
regulator: lochnagar: Add support for the Cirrus Logic Lochnagar
regulator: stpmic1: Return REGULATOR_MODE_INVALID for invalid mode
regulator: stpmic1: add stpmic1 regulator driver
dt-bindings: regulator: document stpmic1 pmic regulators
regulator: axp20x: Mark expected switch fall-throughs
regulator: bd718xx: fix build warning on x86_64
regulator: fixed: Default enable high on DT regulators
regulator: bd718xx: rename bd71837 to 718xx
regulator: bd718XX use pickable ranges
regulator/mfd: bd718xx: rename bd71837/bd71847 common instances
regulator: Support regulators where voltage ranges are selectable
mfd: dt bindings: add BD71847 device-tree binding documentation
regulator: dt bindings: add BD71847 device-tree binding documentation
regulator/mfd: Support ROHM BD71847 power management IC
regulator: da905{2,5}: Remove unnecessary array check
regulator: qcom: Add PMS405 regulators
...
- mostly more consolidation of the direct mapping code, including
converting over hexagon, and merging the coherent and non-coherent
code into a single dma_map_ops instance (me)
- cleanups for the dma_configure/dma_unconfigure callchains (me)
- better handling of dma_masks in odd setups (me, Alexander Duyck)
- better debugging of passing vmalloc address to the DMA API
(Stephen Boyd)
- CMA command line parsing fix (He Zhe)
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Merge tag 'dma-mapping-4.20' of git://git.infradead.org/users/hch/dma-mapping
Pull dma mapping updates from Christoph Hellwig:
"First batch of dma-mapping changes for 4.20.
There will be a second PR as some big changes were only applied just
before the end of the merge window, and I want to give them a few more
days in linux-next.
Summary:
- mostly more consolidation of the direct mapping code, including
converting over hexagon, and merging the coherent and non-coherent
code into a single dma_map_ops instance (me)
- cleanups for the dma_configure/dma_unconfigure callchains (me)
- better handling of dma_masks in odd setups (me, Alexander Duyck)
- better debugging of passing vmalloc address to the DMA API (Stephen
Boyd)
- CMA command line parsing fix (He Zhe)"
* tag 'dma-mapping-4.20' of git://git.infradead.org/users/hch/dma-mapping: (27 commits)
dma-direct: respect DMA_ATTR_NO_WARN
dma-mapping: translate __GFP_NOFAIL to DMA_ATTR_NO_WARN
dma-direct: document the zone selection logic
dma-debug: Check for drivers mapping invalid addresses in dma_map_single()
dma-direct: fix return value of dma_direct_supported
dma-mapping: move dma_default_get_required_mask under ifdef
dma-direct: always allow dma mask <= physiscal memory size
dma-direct: implement complete bus_dma_mask handling
dma-direct: refine dma_direct_alloc zone selection
dma-direct: add an explicit dma_direct_get_required_mask
dma-mapping: make the get_required_mask method available unconditionally
unicore32: remove swiotlb support
Revert "dma-mapping: clear dev->dma_ops in arch_teardown_dma_ops"
dma-mapping: support non-coherent devices in dma_common_get_sgtable
dma-mapping: consolidate the dma mmap implementations
dma-mapping: merge direct and noncoherent ops
dma-mapping: move the dma_coherent flag to struct device
MIPS: don't select DMA_MAYBE_COHERENT from DMA_PERDEV_COHERENT
dma-mapping: add the missing ARCH_HAS_SYNC_DMA_FOR_CPU_ALL declaration
dma-mapping: fix panic caused by passing empty cma command line argument
...
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Merge tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
"This is the main pull request for block changes for 4.20. This
contains:
- Series enabling runtime PM for blk-mq (Bart).
- Two pull requests from Christoph for NVMe, with items such as;
- Better AEN tracking
- Multipath improvements
- RDMA fixes
- Rework of FC for target removal
- Fixes for issues identified by static checkers
- Fabric cleanups, as prep for TCP transport
- Various cleanups and bug fixes
- Block merging cleanups (Christoph)
- Conversion of drivers to generic DMA mapping API (Christoph)
- Series fixing ref count issues with blkcg (Dennis)
- Series improving BFQ heuristics (Paolo, et al)
- Series improving heuristics for the Kyber IO scheduler (Omar)
- Removal of dangerous bio_rewind_iter() API (Ming)
- Apply single queue IPI redirection logic to blk-mq (Ming)
- Set of fixes and improvements for bcache (Coly et al)
- Series closing a hotplug race with sysfs group attributes (Hannes)
- Set of patches for lightnvm:
- pblk trace support (Hans)
- SPDX license header update (Javier)
- Tons of refactoring patches to cleanly abstract the 1.2 and 2.0
specs behind a common core interface. (Javier, Matias)
- Enable pblk to use a common interface to retrieve chunk metadata
(Matias)
- Bug fixes (Various)
- Set of fixes and updates to the blk IO latency target (Josef)
- blk-mq queue number updates fixes (Jianchao)
- Convert a bunch of drivers from the old legacy IO interface to
blk-mq. This will conclude with the removal of the legacy IO
interface itself in 4.21, with the rest of the drivers (me, Omar)
- Removal of the DAC960 driver. The SCSI tree will introduce two
replacement drivers for this (Hannes)"
* tag 'for-4.20/block-20181021' of git://git.kernel.dk/linux-block: (204 commits)
block: setup bounce bio_sets properly
blkcg: reassociate bios when make_request() is called recursively
blkcg: fix edge case for blk_get_rl() under memory pressure
nvme-fabrics: move controller options matching to fabrics
nvme-rdma: always have a valid trsvcid
mtip32xx: fully switch to the generic DMA API
rsxx: switch to the generic DMA API
umem: switch to the generic DMA API
sx8: switch to the generic DMA API
sx8: remove dead IF_64BIT_DMA_IS_POSSIBLE code
skd: switch to the generic DMA API
ubd: remove use of blk_rq_map_sg
nvme-pci: remove duplicate check
drivers/block: Remove DAC960 driver
nvme-pci: fix hot removal during error handling
nvmet-fcloop: suppress a compiler warning
nvme-core: make implicit seed truncation explicit
nvmet-fc: fix kernel-doc headers
nvme-fc: rework the request initialization code
nvme-fc: introduce struct nvme_fcp_op_w_sgl
...
- Core mmu_gather changes which allow tracking the levels of page-table
being cleared together with the arm64 low-level flushing routines
- Support for the new ARMv8.5 PSTATE.SSBS bit which can be used to
mitigate Spectre-v4 dynamically without trapping to EL3 firmware
- Introduce COMPAT_SIGMINSTKSZ for use in compat_sys_sigaltstack
- Optimise emulation of MRS instructions to ID_* registers on ARMv8.4
- Support for Common Not Private (CnP) translations allowing threads of
the same CPU to share the TLB entries
- Accelerated crc32 routines
- Move swapper_pg_dir to the rodata section
- Trap WFI instruction executed in user space
- ARM erratum 1188874 workaround (arch_timer)
- Miscellaneous fixes and clean-ups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
"Apart from some new arm64 features and clean-ups, this also contains
the core mmu_gather changes for tracking the levels of the page table
being cleared and a minor update to the generic
compat_sys_sigaltstack() introducing COMPAT_SIGMINSKSZ.
Summary:
- Core mmu_gather changes which allow tracking the levels of
page-table being cleared together with the arm64 low-level flushing
routines
- Support for the new ARMv8.5 PSTATE.SSBS bit which can be used to
mitigate Spectre-v4 dynamically without trapping to EL3 firmware
- Introduce COMPAT_SIGMINSTKSZ for use in compat_sys_sigaltstack
- Optimise emulation of MRS instructions to ID_* registers on ARMv8.4
- Support for Common Not Private (CnP) translations allowing threads
of the same CPU to share the TLB entries
- Accelerated crc32 routines
- Move swapper_pg_dir to the rodata section
- Trap WFI instruction executed in user space
- ARM erratum 1188874 workaround (arch_timer)
- Miscellaneous fixes and clean-ups"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (78 commits)
arm64: KVM: Guests can skip __install_bp_hardening_cb()s HYP work
arm64: cpufeature: Trap CTR_EL0 access only where it is necessary
arm64: cpufeature: Fix handling of CTR_EL0.IDC field
arm64: cpufeature: ctr: Fix cpu capability check for late CPUs
Documentation/arm64: HugeTLB page implementation
arm64: mm: Use __pa_symbol() for set_swapper_pgd()
arm64: Add silicon-errata.txt entry for ARM erratum 1188873
Revert "arm64: uaccess: implement unsafe accessors"
arm64: mm: Drop the unused cpu parameter
MAINTAINERS: fix bad sdei paths
arm64: mm: Use #ifdef for the __PAGETABLE_P?D_FOLDED defines
arm64: Fix typo in a comment in arch/arm64/mm/kasan_init.c
arm64: xen: Use existing helper to check interrupt status
arm64: Use daifflag_restore after bp_hardening
arm64: daifflags: Use irqflags functions for daifflags
arm64: arch_timer: avoid unused function warning
arm64: Trap WFI executed in userspace
arm64: docs: Document SSBS HWCAP
arm64: docs: Fix typos in ELF hwcaps
arm64/kprobes: remove an extra semicolon in arch_prepare_kprobe
...
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-10-21
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Implement two new kind of BPF maps, that is, queue and stack
map along with new peek, push and pop operations, from Mauricio.
2) Add support for MSG_PEEK flag when redirecting into an ingress
psock sk_msg queue, and add a new helper bpf_msg_push_data() for
insert data into the message, from John.
3) Allow for BPF programs of type BPF_PROG_TYPE_CGROUP_SKB to use
direct packet access for __skb_buff, from Song.
4) Use more lightweight barriers for walking perf ring buffer for
libbpf and perf tool as well. Also, various fixes and improvements
from verifier side, from Daniel.
5) Add per-symbol visibility for DSO in libbpf and hide by default
global symbols such as netlink related functions, from Andrey.
6) Two improvements to nfp's BPF offload to check vNIC capabilities
in case prog is shared with multiple vNICs and to protect against
mis-initializing atomic counters, from Jakub.
7) Fix for bpftool to use 4 context mode for the nfp disassembler,
also from Jakub.
8) Fix a return value comparison in test_libbpf.sh and add several
bpftool improvements in bash completion, documentation of bpf fs
restrictions and batch mode summary print, from Quentin.
9) Fix a file resource leak in BPF selftest's load_kallsyms()
helper, from Peng.
10) Fix an unused variable warning in map_lookup_and_delete_elem(),
from Alexei.
11) Fix bpf_skb_adjust_room() signature in BPF UAPI helper doc,
from Nicolas.
12) Add missing executables to .gitignore in BPF selftests, from Anders.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The following commit:
d7880812b3 ("idle: Add the stack canary init to cpu_startup_entry()")
... added an x86 specific boot_init_stack_canary() call to the generic
cpu_startup_entry() as a temporary hack, with the intention to remove
the #ifdef CONFIG_X86 later.
More than 5 years later let's finally realize that plan! :-)
While implementing stack protector support for PowerPC, we found
that calling boot_init_stack_canary() is also needed for PowerPC
which uses per task (TLS) stack canary like the X86.
However, calling boot_init_stack_canary() would break architectures
using a global stack canary (ARM, SH, MIPS and XTENSA).
Instead of modifying the #ifdef CONFIG_X86 to an even messier:
#if defined(CONFIG_X86) || defined(CONFIG_PPC)
PowerPC implemented the call to boot_init_stack_canary() in the function
calling cpu_startup_entry().
Let's try the same cleanup on the x86 side as well.
On x86 we have two functions calling cpu_startup_entry():
- start_secondary()
- cpu_bringup_and_idle()
start_secondary() already calls boot_init_stack_canary(), so
it's good, and this patch adds the call to boot_init_stack_canary()
in cpu_bringup_and_idle().
I.e. now x86 catches up to the rest of the world and the ugly init
sequence in init/main.c can be removed from cpu_startup_entry().
As a final benefit we can also remove the <linux/stackprotector.h>
dependency from <linux/sched.h>.
[ mingo: Improved the changelog a bit, added language explaining x86 borkage and sched.h change. ]
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181020072649.5B59310483E@pc16082vm.idsi0.si.c-s.fr
Signed-off-by: Ingo Molnar <mingo@kernel.org>
David Ahern's dump indexing bug fix in 'net' overlapped the
change of the function signature of inet6_fill_ifaddr() in
'net-next'. Trivially resolved.
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend prior work from 09772d92cd ("bpf: avoid retpoline for
lookup/update/delete calls on maps") to also apply to the recently
added map helpers that perform push/pop/peek operations so that
the indirect call can be avoided.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
They PTR_TO_FLOW_KEYS is not used today to be passed into a helper
as memory, so it can be removed from check_helper_mem_access().
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
We should not enable xadd operation for flow key memory if not
needed there anyway. There is no such issue as described in the
commit f37a8cb84c ("bpf: reject stores into ctx via st and xadd")
since there's no context rewriter for flow keys today, but it
also shouldn't become part of the user facing behavior to allow
for it. After patch:
0: (79) r7 = *(u64 *)(r1 +144)
1: (b7) r3 = 4096
2: (db) lock *(u64 *)(r7 +0) += r3
BPF_XADD stores into R7 flow_keys is not allowed
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Using reg_type_str[insn->dst_reg] is incorrect since insn->dst_reg
contains the register number but not the actual register type. Add
a small reg_state() helper and use it to get to the type. Also fix
up the test_verifier test cases that have an incorrect errstr.
Fixes: 9d2be44a7f ("bpf: Reuse canonical string formatter for ctx errs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Ingo writes:
"scheduler fixes:
Two fixes: a CFS-throttling bug fix, and an interactivity fix."
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix the min_vruntime update logic in dequeue_entity()
sched/fair: Fix throttle_list starvation with low CFS quota
The first two patches fix handling of unsigned type, and handling
of a space before an ending semi-colon.
The third patch adds a selftest to test the processing of synthetic events.
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Merge tag 'trace-v4.19-rc8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Steven writes:
"tracing: A few small fixes to synthetic events
Masami found some issues with the creation of synthetic events. The
first two patches fix handling of unsigned type, and handling of a
space before an ending semi-colon.
The third patch adds a selftest to test the processing of synthetic
events."
* tag 'trace-v4.19-rc8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests: ftrace: Add synthetic event syntax testcase
tracing: Fix synthetic event to allow semicolon at end
tracing: Fix synthetic event to accept unsigned modifier
Fix synthetic event to allow independent semicolon at end.
The synthetic_events interface accepts a semicolon after the
last word if there is no space.
# echo "myevent u64 var;" >> synthetic_events
But if there is a space, it returns an error.
# echo "myevent u64 var ;" > synthetic_events
sh: write error: Invalid argument
This behavior is difficult for users to understand. Let's
allow the last independent semicolon too.
Link: http://lkml.kernel.org/r/153986835420.18251.2191216690677025744.stgit@devbox
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: stable@vger.kernel.org
Fixes: commit 4b147936fa ("tracing: Add support for 'synthetic' events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix synthetic event to accept unsigned modifier for its field type
correctly.
Currently, synthetic_events interface returns error for "unsigned"
modifiers as below;
# echo "myevent unsigned long var" >> synthetic_events
sh: write error: Invalid argument
This is because argv_split() breaks "unsigned long" into "unsigned"
and "long", but parse_synth_field() doesn't expected it.
With this fix, synthetic_events can handle the "unsigned long"
correctly like as below;
# echo "myevent unsigned long var" >> synthetic_events
# cat synthetic_events
myevent unsigned long var
Link: http://lkml.kernel.org/r/153986832571.18251.8448135724590496531.stgit@devbox
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: stable@vger.kernel.org
Fixes: commit 4b147936fa ("tracing: Add support for 'synthetic' events")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
BPF programs of BPF_PROG_TYPE_CGROUP_SKB need to access headers in the
skb. This patch enables direct access of skb for these programs.
Two helper functions bpf_compute_and_save_data_end() and
bpf_restore_data_end() are introduced. There are used in
__cgroup_bpf_run_filter_skb(), to compute proper data_end for the
BPF program, and restore original data afterwards.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The previous patch implemented a bpf queue/stack maps that
provided the peek/pop/push functions. There is not a direct
relationship between those functions and the current maps
syscalls, hence a new MAP_LOOKUP_AND_DELETE_ELEM syscall is added,
this is mapped to the pop operation in the queue/stack maps
and it is still to implement in other kind of maps.
Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Queue/stack maps implement a FIFO/LIFO data storage for ebpf programs.
These maps support peek, pop and push operations that are exposed to eBPF
programs through the new bpf_map[peek/pop/push] helpers. Those operations
are exposed to userspace applications through the already existing
syscalls in the following way:
BPF_MAP_LOOKUP_ELEM -> peek
BPF_MAP_LOOKUP_AND_DELETE_ELEM -> pop
BPF_MAP_UPDATE_ELEM -> push
Queue/stack maps are implemented using a buffer, tail and head indexes,
hence BPF_F_NO_PREALLOC is not supported.
As opposite to other maps, queue and stack do not use RCU for protecting
maps values, the bpf_map[peek/pop] have a ARG_PTR_TO_UNINIT_MAP_VALUE
argument that is a pointer to a memory zone where to save the value of a
map. Basically the same as ARG_PTR_TO_UNINIT_MEM, but the size has not
be passed as an extra argument.
Our main motivation for implementing queue/stack maps was to keep track
of a pool of elements, like network ports in a SNAT, however we forsee
other use cases, like for exampling saving last N kernel events in a map
and then analysing from userspace.
Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
ARG_PTR_TO_UNINIT_MAP_VALUE argument is a pointer to a memory zone
used to save the value of a map. Basically the same as
ARG_PTR_TO_UNINIT_MEM, but the size has not be passed as an extra
argument.
This will be used in the following patch that implements some new
helpers that receive a pointer to be filled with a map value.
Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit adds the required logic to allow key being NULL
in case the key_size of the map is 0.
A new __bpf_copy_key function helper only copies the key from
userpsace when key_size != 0, otherwise it enforces that key must be
null.
Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
In the following patches queue and stack maps (FIFO and LIFO
datastructures) will be implemented. In order to avoid confusion and
a possible name clash rename stack_map_ops to stack_trace_map_ops
Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.
net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'. Thanks to David
Ahern for the heads up.
Signed-off-by: David S. Miller <davem@davemloft.net>
David writes:
"Networking
1) Fix gro_cells leak in xfrm layer, from Li RongQing.
2) BPF selftests change RLIMIT_MEMLOCK blindly, don't do that. From
Eric Dumazet.
3) AF_XDP calls synchronize_net() under RCU lock, fix from Björn
Töpel.
4) Out of bounds packet access in _decode_session6(), from Alexei
Starovoitov.
5) Several ethtool bugs, where we copy a struct into the kernel twice
and our validations of the values in the first copy can be
invalidated by the second copy due to asynchronous updates to the
memory by the user. From Wenwen Wang.
6) Missing netlink attribute validation in cls_api, from Davide
Caratti.
7) LLC SAP sockets neet to be SOCK_RCU FREE, from Cong Wang.
8) rxrpc operates on wrong kvec, from Yue Haibing.
9) A regression was introduced by the disassosciation of route
neighbour references in rt6_probe(), causing probe for
neighbourless routes to not be properly rate limited. Fix from
Sabrina Dubroca.
10) Unsafe RCU locking in tipc, from Tung Nguyen.
11) Use after free in inet6_mc_check(), from Eric Dumazet.
12) PMTU from icmp packets should update the SCTP transport pathmtu,
from Xin Long.
13) Missing peer put on error in rxrpc, from David Howells.
14) Fix pedit in nfp driver, from Pieter Jansen van Vuuren.
15) Fix overflowing shift statement in qla3xxx driver, from Nathan
Chancellor.
16) Fix Spectre v1 in ptp code, from Gustavo A. R. Silva.
17) udp6_unicast_rcv_skb() interprets udpv6_queue_rcv_skb() return
value in an inverted manner, fix from Paolo Abeni.
18) Fix missed unresolved entries in ipmr dumps, from Nikolay
Aleksandrov.
19) Fix NAPI handling under high load, we can completely miss events
when NAPI has to loop more than one time in a cycle. From Heiner
Kallweit."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (49 commits)
ip6_tunnel: Fix encapsulation layout
tipc: fix info leak from kernel tipc_event
net: socket: fix a missing-check bug
net: sched: Fix for duplicate class dump
r8169: fix NAPI handling under high load
net: ipmr: fix unresolved entry dumps
net: mscc: ocelot: Fix comment in ocelot_vlant_wait_for_completion()
sctp: fix the data size calculation in sctp_data_size
virtio_net: avoid using netif_tx_disable() for serializing tx routine
udp6: fix encap return code for resubmitting
mlxsw: core: Fix use-after-free when flashing firmware during init
sctp: not free the new asoc when sctp_wait_for_connect returns err
sctp: fix race on sctp_id2asoc
r8169: re-enable MSI-X on RTL8168g
net: bpfilter: use get_pid_task instead of pid_task
ptp: fix Spectre v1 vulnerability
net: qla3xxx: Remove overflowing shift statement
geneve, vxlan: Don't set exceptions if skb->len < mtu
geneve, vxlan: Don't check skb_dst() twice
sctp: get pr_assoc and pr_stream all status with SCTP_PR_SCTP_ALL instead
...
It was found that when debug_locks was turned off because of a problem
found by the lockdep code, the system performance could drop quite
significantly when the lock_stat code was also configured into the
kernel. For instance, parallel kernel build time on a 4-socket x86-64
server nearly doubled.
Further analysis into the cause of the slowdown traced back to the
frequent call to debug_locks_off() from the __lock_acquired() function
probably due to some inconsistent lockdep states with debug_locks
off. The debug_locks_off() function did an unconditional atomic xchg
to write a 0 value into debug_locks which had already been set to 0.
This led to severe cacheline contention in the cacheline that held
debug_locks. As debug_locks is being referenced in quite a few different
places in the kernel, this greatly slow down the system performance.
To prevent that trashing of debug_locks cacheline, lock_acquired()
and lock_contended() now checks the state of debug_locks before
proceeding. The debug_locks_off() function is also modified to check
debug_locks before calling __debug_locks_off().
Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1539913518-15598-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
* acpi-pm:
ACPI / PM: LPIT: Register sysfs attributes based on FADT
* pm-sleep:
x86-32, hibernate: Adjust in_suspend after resumed on 32bit system
x86-32, hibernate: Set up temporary text mapping for 32bit system
x86-32, hibernate: Switch to relocated restore code during resume on 32bit system
x86-32, hibernate: Switch to original page table after resumed
x86-32, hibernate: Use the page size macro instead of constant value
x86-32, hibernate: Use temp_pgt as the temporary page table
x86, hibernate: Rename temp_level4_pgt to temp_pgt
x86-32, hibernate: Enable CONFIG_ARCH_HIBERNATION_HEADER on 32bit system
x86, hibernate: Extract the common code of 64/32 bit system
x86-32/asm/power: Create stack frames in hibernate_asm_32.S
PM / hibernate: Check the success of generating md5 digest before hibernation
x86, hibernate: Fix nosave_regions setup for hibernation
PM / sleep: Show freezing tasks that caused a suspend abort
PM / hibernate: Documentation: fix image_size default value
- Fix size mismatch of tracepoint array
- Have preemptirq test module use same clock source of the selftest
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Merge tag 'trace-v4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Steven writes:
"tracing: Two fixes for 4.19
This fixes two bugs:
- Fix size mismatch of tracepoint array
- Have preemptirq test module use same clock source of the selftest"
* tag 'trace-v4.19-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c
tracepoint: Fix tracepoint array element size mismatch
The preemptirq_delay_test module is used for the ftrace selftest code that
tests the latency tracers. The problem is that it uses ktime for the delay
loop, and then checks the tracer to see if the delay loop is caught, but the
tracer uses trace_clock_local() which uses various different other clocks to
measure the latency. As ktime uses the clock cycles, and the code then
converts that to nanoseconds, it causes rounding errors, and the preemptirq
latency tests are failing due to being off by 1 (it expects to see a delay
of 500000 us, but the delay is only 499999 us). This is happening due to a
rounding error in the ktime (which is totally legit). The purpose of the
test is to see if it can catch the delay, not to test the accuracy between
trace_clock_local() and ktime_get(). Best to use apples to apples, and have
the delay loop use the same clock as the latency tracer does.
Cc: stable@vger.kernel.org
Fixes: f96e8577da ("lib: Add module for testing preemptoff/irqsoff latency tracers")
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
commit 46e0c9be20 ("kernel: tracepoints: add support for relative
references") changes the layout of the __tracepoint_ptrs section on
architectures supporting relative references. However, it does so
without turning struct tracepoint * const into const int elsewhere in
the tracepoint code, which has the following side-effect:
Setting mod->num_tracepoints is done in by module.c:
mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
sizeof(*mod->tracepoints_ptrs),
&mod->num_tracepoints);
Basically, since sizeof(*mod->tracepoints_ptrs) is a pointer size
(rather than sizeof(int)), num_tracepoints is erroneously set to half the
size it should be on 64-bit arch. So a module with an odd number of
tracepoints misses the last tracepoint due to effect of integer
division.
So in the module going notifier:
for_each_tracepoint_range(mod->tracepoints_ptrs,
mod->tracepoints_ptrs + mod->num_tracepoints,
tp_module_going_check_quiescent, NULL);
the expression (mod->tracepoints_ptrs + mod->num_tracepoints) actually
evaluates to something within the bounds of the array, but miss the
last tracepoint if the number of tracepoints is odd on 64-bit arch.
Fix this by introducing a new typedef: tracepoint_ptr_t, which
is either "const int" on architectures that have PREL32 relocations,
or "struct tracepoint * const" on architectures that does not have
this feature.
Also provide a new tracepoint_ptr_defer() static inline to
encapsulate deferencing this type rather than duplicate code and
ugly idefs within the for_each_tracepoint_range() implementation.
This issue appears in 4.19-rc kernels, and should ideally be fixed
before the end of the rc cycle.
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Link: http://lkml.kernel.org/r/20181013191050.22389-1-mathieu.desnoyers@efficios.com
Link: http://lkml.kernel.org/r/20180704083651.24360-7-ard.biesheuvel@linaro.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <james.morris@microsoft.com>
Cc: James Morris <jmorris@namei.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The qspinlock code supports up to 4 levels of slowpath nesting using
four per-CPU mcs_spinlock structures. For 64-bit architectures, they
fit nicely in one 64-byte cacheline.
For para-virtualized (PV) qspinlocks it needs to store more information
in the per-CPU node structure than there is space for. It uses a trick
to use a second cacheline to hold the extra information that it needs.
So PV qspinlock needs to access two extra cachelines for its information
whereas the native qspinlock code only needs one extra cacheline.
Freshly added counter profiling of the qspinlock code, however, revealed
that it was very rare to use more than two levels of slowpath nesting.
So it doesn't make sense to penalize PV qspinlock code in order to have
four mcs_spinlock structures in the same cacheline to optimize for a case
in the native qspinlock code that rarely happens.
Extend the per-CPU node structure to have two more long words when PV
qspinlock locks are configured to hold the extra data that it needs.
As a result, the PV qspinlock code will enjoy the same benefit of using
just one extra cacheline like the native counterpart, for most cases.
[ mingo: Minor changelog edits. ]
Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1539697507-28084-2-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Queued spinlock supports up to 4 levels of lock slowpath nesting -
user context, soft IRQ, hard IRQ and NMI. However, we are not sure how
often the nesting happens.
So add 3 more per-CPU stat counters to track the number of instances where
nesting index goes to 1, 2 and 3 respectively.
On a dual-socket 64-core 128-thread Zen server, the following were the
new stat counter values under different circumstances:
State slowpath index1 index2 index3
----- -------- ------ ------ -------
After bootup 1,012,150 82 0 0
After parallel build + perf-top 125,195,009 82 0 0
So the chance of having more than 2 levels of nesting is extremely low.
[ mingo: Minor changelog edits. ]
Signed-off-by: Waiman Long <longman@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/1539697507-28084-1-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On x86 we cannot do fetch_or() with a single instruction and thus end up
using a cmpxchg loop, this reduces determinism. Replace the fetch_or()
with a composite operation: tas-pending + load.
Using two instructions of course opens a window we previously did not
have. Consider the scenario:
CPU0 CPU1 CPU2
1) lock
trylock -> (0,0,1)
2) lock
trylock /* fail */
3) unlock -> (0,0,0)
4) lock
trylock -> (0,0,1)
5) tas-pending -> (0,1,1)
load-val <- (0,1,0) from 3
6) clear-pending-set-locked -> (0,0,1)
FAIL: _2_ owners
where 5) is our new composite operation. When we consider each part of
the qspinlock state as a separate variable (as we can when
_Q_PENDING_BITS == 8) then the above is entirely possible, because
tas-pending will only RmW the pending byte, so the later load is able
to observe prior tail and lock state (but not earlier than its own
trylock, which operates on the whole word, due to coherence).
To avoid this we need 2 things:
- the load must come after the tas-pending (obviously, otherwise it
can trivially observe prior state).
- the tas-pending must be a full word RmW instruction, it cannot be an XCHGB for
example, such that we cannot observe other state prior to setting
pending.
On x86 we can realize this by using "LOCK BTS m32, r32" for
tas-pending followed by a regular load.
Note that observing later state is not a problem:
- if we fail to observe a later unlock, we'll simply spin-wait for
that store to become visible.
- if we observe a later xchg_tail(), there is no difference from that
xchg_tail() having taken place before the tas-pending.
Suggested-by: Will Deacon <will.deacon@arm.com>
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: andrea.parri@amarulasolutions.com
Cc: longman@redhat.com
Fixes: 59fb586b4a ("locking/qspinlock: Remove unbounded cmpxchg() loop from locking slowpath")
Link: https://lkml.kernel.org/r/20181003130957.183726335@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While working my way through the code again; I felt the comments could
use help.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andrea.parri@amarulasolutions.com
Cc: longman@redhat.com
Link: https://lkml.kernel.org/r/20181003130257.156322446@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
