And rename it to modify_user_hw_breakpoint_check().
We are about to use modify_user_hw_breakpoint_check() for user space
breakpoints modification, we must be very strict to check only the
fields we can change have changed. As Peter explained:
"Suppose someone does:
attr = malloc(sizeof(*attr)); // uninitialized memory
attr->type = BP;
attr->bp_addr = new_addr;
attr->bp_type = bp_type;
attr->bp_len = bp_len;
ioctl(fd, PERF_IOC_MOD_ATTR, &attr);
And feeds absolute shite for the rest of the fields.
Then we later want to extend IOC_MOD_ATTR to allow changing
attr::sample_type but we can't, because that would break the
above application."
I'm making this check optional because we already export
modify_user_hw_breakpoint() and with this check we could
break existing users.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milind Chabbi <chabbi.milind@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180312134548.31532-6-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Moving out all the functionality without the events
disabling/enabling calls, because we want to call another
disabling/enabling functions in following change.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milind Chabbi <chabbi.milind@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180312134548.31532-5-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add the modify_bp_slot() function to keep slot numbers
correct when changing the breakpoint type.
Using existing __release_bp_slot()/__reserve_bp_slot()
call sequence to update the slot counts.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milind Chabbi <chabbi.milind@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180312134548.31532-4-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Passing bp_type argument to __reserve_bp_slot() and __release_bp_slot()
functions, so we can pass another bp_type than the one defined in
bp->attr.bp_type. This will be handy in following change that fixes
breakpoint slot counts during its modification.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milind Chabbi <chabbi.milind@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180312134548.31532-3-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pass bp_type directly as a find_slot_idx() argument,
so we don't need to have whole event to get the
breakpoint slot type. It will be used in following
changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Milind Chabbi <chabbi.milind@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180312134548.31532-2-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since the kprobe which was optimized by jump can not change
the execution path, the kprobe for error-injection must not
be optimized. To prohibit it, set a dummy post-handler as
officially stated in Documentation/kprobes.txt.
Fixes: 4b1a29a7f5 ("error-injection: Support fault injection framework")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
There's two problems when installing cgroup events on CPUs: firstly
list_update_cgroup_event() only tries to set cpuctx->cgrp for the
first event, if that mismatches on @cgrp we'll not try again for later
additions.
Secondly, when we install a cgroup event into an active context, only
issue an event reprogram when the event matches the current cgroup
context. This avoids a pointless event reprogramming.
Signed-off-by: leilei.lin <leilei.lin@alibaba-inc.com>
[ Improved the changelog and comments. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: brendan.d.gregg@gmail.com
Cc: eranian@gmail.com
Cc: linux-kernel@vger.kernel.org
Cc: yang_oliver@hotmail.com
Link: http://lkml.kernel.org/r/20180306093637.28247-1-linxiulei@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The event schedule order (as per perf_event_sched_in()) is:
- cpu pinned
- task pinned
- cpu flexible
- task flexible
But perf_rotate_context() will unschedule cpu-flexible even if it
doesn't need a rotation.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Similar to how first programming cpu=-1 and then cpu=# is wrong, so is
rotating both. It was especially wrong when we were still programming
the PMU in this same order, because in that scenario we might never
actually end up running cpu=# events at all.
Cure this by using the active_list to pick the rotation event; since
at programming we already select the left-most event.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The last argument is, and always must be, the same.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When an event group contains more events than can be scheduled on the
hardware, iterating the full event group for ctx_sched_out is a waste
of time.
Keep track of the events that got programmed on the hardware, such
that we can iterate this smaller list in order to schedule them out.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that all the grouping is done with RB trees, we no longer need
group_entry and can replace the whole thing with sibling_list.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Scheduling in events with cpu=-1 before events with cpu=# changes
semantics and is undesirable in that it would priorize these events.
Given that groups->index is across all groups we actually have an
inter-group ordering, meaning we can merge-sort two groups, which is
just what we need to preserve semantics.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Change event groups into RB trees sorted by CPU and then by a 64bit
index, so that multiplexing hrtimer interrupt handler would be able
skipping to the current CPU's list and ignore groups allocated for the
other CPUs.
New API for manipulating event groups in the trees is implemented as well
as adoption on the API in the current implementation.
pinned_group_sched_in() and flexible_group_sched_in() API are
introduced to consolidate code enabling the whole group from pinned
and flexible groups appropriately.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/372f9c8b-0cfe-4240-e44d-83d863d40813@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Mark reported his arm64 perf fuzzer runs sometimes splat like:
armv8pmu_read_counter+0x1e8/0x2d8
armpmu_event_update+0x8c/0x188
armpmu_read+0xc/0x18
perf_output_read+0x550/0x11e8
perf_event_read_event+0x1d0/0x248
perf_event_exit_task+0x468/0xbb8
do_exit+0x690/0x1310
do_group_exit+0xd0/0x2b0
get_signal+0x2e8/0x17a8
do_signal+0x144/0x4f8
do_notify_resume+0x148/0x1e8
work_pending+0x8/0x14
which asserts that we only call pmu::read() on ACTIVE events.
The above callchain does:
perf_event_exit_task()
perf_event_exit_task_context()
task_ctx_sched_out() // INACTIVE
perf_event_exit_event()
perf_event_set_state(EXIT) // EXIT
sync_child_event()
perf_event_read_event()
perf_output_read()
perf_output_read_group()
leader->pmu->read()
Which results in doing a pmu::read() on an !ACTIVE event.
I _think_ this is 'new' since we added attr.inherit_stat, which added
the perf_event_read_event() to the exit path, without that
perf_event_read_output() would only trigger from samples and for
@event to trigger a sample, it's leader _must_ be ACTIVE too.
Still, adding this check makes it consistent with the @sub case for
the siblings.
Reported-and-Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf updates from Thomas Gleixner:
"Another set of perf updates:
- Fix a Skylake Uncore event format declaration
- Prevent perf pipe mode from crahsing which was caused by a missing
buffer allocation
- Make the perf top popup message which tells the user that it uses
fallback mode on older kernels a debug message.
- Make perf context rescheduling work correcctly
- Robustify the jump error drawing in perf browser mode so it does
not try to create references to NULL initialized offset entries
- Make trigger_on() robust so it does not enable the trigger before
everything is set up correctly to handle it
- Make perf auxtrace respect the --no-itrace option so it does not
try to queue AUX data for decoding.
- Prevent having different number of field separators in CVS output
lines when a counter is not supported.
- Make the perf kallsyms man page usage behave like it does for all
other perf commands.
- Synchronize the kernel headers"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix ctx_event_type in ctx_resched()
perf tools: Fix trigger class trigger_on()
perf auxtrace: Prevent decoding when --no-itrace
perf stat: Fix CVS output format for non-supported counters
tools headers: Sync x86's cpufeatures.h
tools headers: Sync copy of kvm UAPI headers
perf record: Fix crash in pipe mode
perf annotate browser: Be more robust when drawing jump arrows
perf top: Fix annoying fallback message on older kernels
perf kallsyms: Fix the usage on the man page
perf/x86/intel/uncore: Fix Skylake UPI event format
Pull locking fix from Thomas Gleixner:
"rt_mutex_futex_unlock() grew a new irq-off call site, but the function
assumes that its always called from irq enabled context.
Use (un)lock_irqsafe() to handle the new call site correctly"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rtmutex: Make rt_mutex_futex_unlock() safe for irq-off callsites
Pull RCU updates from Paul E. McKenney:
- Miscellaneous fixes, perhaps most notably removing obsolete
code whose only purpose in life was to gather information for
the now-removed RCU debugfs facility. Other notable changes
include removing NO_HZ_FULL_ALL in favor of the nohz_full kernel
boot parameter, minor optimizations for expedited grace periods,
some added tracing, creating an RCU-specific workqueue using Tejun's
new WQ_MEM_RECLAIM flag, and several cleanups to code and comments.
- SRCU cleanups and optimizations.
- Torture-test updates, perhaps most notably the adding of ARMv8
support, but also including numerous cleanups and usability fixes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The BUG and stack protector reports were still using a raw %p. This
changes it to %pB for more meaningful output.
Link: http://lkml.kernel.org/r/20180301225704.GA34198@beast
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Richard Weinberger <richard.weinberger@gmail.com>,
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When running rcutorture with TREE03 config, CONFIG_PROVE_LOCKING=y, and
kernel cmdline argument "rcutorture.gp_exp=1", lockdep reports a
HARDIRQ-safe->HARDIRQ-unsafe deadlock:
================================
WARNING: inconsistent lock state
4.16.0-rc4+ #1 Not tainted
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
takes:
__schedule+0xbe/0xaf0
{IN-HARDIRQ-W} state was registered at:
_raw_spin_lock+0x2a/0x40
scheduler_tick+0x47/0xf0
...
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&rq->lock);
<Interrupt>
lock(&rq->lock);
*** DEADLOCK ***
1 lock held by rcu_torture_rea/724:
rcu_torture_read_lock+0x0/0x70
stack backtrace:
CPU: 2 PID: 724 Comm: rcu_torture_rea Not tainted 4.16.0-rc4+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
Call Trace:
lock_acquire+0x90/0x200
? __schedule+0xbe/0xaf0
_raw_spin_lock+0x2a/0x40
? __schedule+0xbe/0xaf0
__schedule+0xbe/0xaf0
preempt_schedule_irq+0x2f/0x60
retint_kernel+0x1b/0x2d
RIP: 0010:rcu_read_unlock_special+0x0/0x680
? rcu_torture_read_unlock+0x60/0x60
__rcu_read_unlock+0x64/0x70
rcu_torture_read_unlock+0x17/0x60
rcu_torture_reader+0x275/0x450
? rcutorture_booster_init+0x110/0x110
? rcu_torture_stall+0x230/0x230
? kthread+0x10e/0x130
kthread+0x10e/0x130
? kthread_create_worker_on_cpu+0x70/0x70
? call_usermodehelper_exec_async+0x11a/0x150
ret_from_fork+0x3a/0x50
This happens with the following even sequence:
preempt_schedule_irq();
local_irq_enable();
__schedule():
local_irq_disable(); // irq off
...
rcu_note_context_switch():
rcu_note_preempt_context_switch():
rcu_read_unlock_special():
local_irq_save(flags);
...
raw_spin_unlock_irqrestore(...,flags); // irq remains off
rt_mutex_futex_unlock():
raw_spin_lock_irq();
...
raw_spin_unlock_irq(); // accidentally set irq on
<return to __schedule()>
rq_lock():
raw_spin_lock(); // acquiring rq->lock with irq on
which means rq->lock becomes a HARDIRQ-unsafe lock, which can cause
deadlocks in scheduler code.
This problem was introduced by commit 02a7c234e5 ("rcu: Suppress
lockdep false-positive ->boost_mtx complaints"). That brought the user
of rt_mutex_futex_unlock() with irq off.
To fix this, replace the *lock_irq() in rt_mutex_futex_unlock() with
*lock_irq{save,restore}() to make it safe to call rt_mutex_futex_unlock()
with irq off.
Fixes: 02a7c234e5 ("rcu: Suppress lockdep false-positive ->boost_mtx complaints")
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20180309065630.8283-1-boqun.feng@gmail.com
When pinning a file under the BPF virtual file system (traditionally
/sys/fs/bpf), using a dot in the name of the location to pin at is not
allowed. For example, trying to pin at "/sys/fs/bpf/foo.bar" will be
rejected with -EPERM.
This check was introduced at the same time as the BPF file system
itself, with commit b2197755b2 ("bpf: add support for persistent
maps/progs"). At this time, it was checked in a function called
"bpf_dname_reserved()", which made clear that using a dot was reserved
for future extensions.
This function disappeared and the check was moved elsewhere with commit
0c93b7d85d ("bpf: reject invalid names right in ->lookup()"), and the
meaning of the dot ban was lost.
The present commit simply adds a comment in the source to explain to the
reader that the usage of dots is reserved for future usage.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
In ctx_resched(), EVENT_FLEXIBLE should be sched_out when EVENT_PINNED is
added. However, ctx_resched() calculates ctx_event_type before checking
this condition. As a result, pinned events will NOT get higher priority
than flexible events.
The following shows this issue on an Intel CPU (where ref-cycles can
only use one hardware counter).
1. First start:
perf stat -C 0 -e ref-cycles -I 1000
2. Then, in the second console, run:
perf stat -C 0 -e ref-cycles:D -I 1000
The second perf uses pinned events, which is expected to have higher
priority. However, because it failed in ctx_resched(). It is never
run.
This patch fixes this by calculating ctx_event_type after re-evaluating
event_type.
Reported-by: Ephraim Park <ephiepark@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <jolsa@redhat.com>
Cc: <kernel-team@fb.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 487f05e18a ("perf/core: Optimize event rescheduling on active contexts")
Link: http://lkml.kernel.org/r/20180306055504.3283731-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since the return type of the function is bool, the internal
'ret' variable should be bool too.
Signed-off-by: Gaurav Jindal<gauravjindal1104@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180221125407.GA14292@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When NEWLY_IDLE load balance is not triggered, we might need to update the
blocked load anyway. We can kick an ilb so an idle CPU will take care of
updating blocked load or we can try to update them locally before entering
idle. In the latter case, we reuse part of the nohz_idle_balance.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: brendan.jackman@arm.com
Cc: dietmar.eggemann@arm.com
Cc: morten.rasmussen@foss.arm.com
Cc: valentin.schneider@arm.com
Link: http://lkml.kernel.org/r/1518622006-16089-4-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We're going to want to call nohz_idle_balance() or parts thereof from
idle_balance(). Since we already have a forward declaration of
idle_balance() move it down such that it's below nohz_idle_balance()
avoiding the need for a forward declaration for that.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that we have two back-to-back NO_HZ_COMMON blocks, merge them.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This pure code movement results in two #ifdef CONFIG_NO_HZ_COMMON
sections landing next to each other.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Avoid calling update_blocked_averages() when it does not in fact have
any by re-using/extending update_nohz_stats().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Instead of using the cfs_rq_is_decayed() which monitors all *_avg
and *_sum, we create a cfs_rq_has_blocked() which only takes care of
util_avg and load_avg. We are only interested by these 2 values which are
decaying faster than the *_sum so we can stop the periodic update earlier.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: brendan.jackman@arm.com
Cc: dietmar.eggemann@arm.com
Cc: morten.rasmussen@foss.arm.com
Cc: valentin.schneider@arm.com
Link: http://lkml.kernel.org/r/1518517879-2280-3-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Stopped the periodic update of blocked load when all idle CPUs have fully
decayed. We introduce a new nohz.has_blocked that reflect if some idle
CPUs has blocked load that have to be periodiccally updated. nohz.has_blocked
is set everytime that a Idle CPU can have blocked load and it is then clear
when no more blocked load has been detected during an update. We don't need
atomic operation but only to make cure of the right ordering when updating
nohz.idle_cpus_mask and nohz.has_blocked.
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: brendan.jackman@arm.com
Cc: dietmar.eggemann@arm.com
Cc: morten.rasmussen@foss.arm.com
Cc: valentin.schneider@arm.com
Link: http://lkml.kernel.org/r/1518517879-2280-2-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It was suggested that a migration hint might be usefull for the
CPU-freq governors.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The primary observation is that nohz enter/exit is always from the
current CPU, therefore NOHZ_TICK_STOPPED does not in fact need to be
an atomic.
Secondary is that we appear to have 2 nearly identical hooks in the
nohz enter code, set_cpu_sd_state_idle() and
nohz_balance_enter_idle(). Fold the whole set_cpu_sd_state thing into
nohz_balance_{enter,exit}_idle.
Removes an atomic op from both enter and exit paths.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since we already iterate CPUs looking for work on NEWIDLE, use this
iteration to age the blocked load. If the domain for which this is
done completely spand the idle set, we can push the ILB based aging
forward.
Suggested-by: Brendan Jackman <brendan.jackman@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Teach the idle balancer about the need to update statistics which have
a different periodicity from regular balancing.
Suggested-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current:
if (nohz_kick_needed())
nohz_balancer_kick()
is pointless complexity, fold them into a single call and avoid the
various conditions at the call site.
When we introduce multiple different needs to kick the ilb, the above
construct also becomes a problem.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Split the NOHZ idle balancer into doing two separate actions:
- update blocked load statistic
- actually load-balance
Since the latter requires the former, ensure this happens. For now
always tag both bits at the same time.
Prepares for a future where we can toggle only the STATS bit.
Suggested-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Using atomic_t allows us to use the more flexible bitops provided
there. Also its smaller.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Instead of trying to duplicate scheduler state to track if an RT task
is running, directly use the scheduler runqueue state for it.
This vastly simplifies things and fixes a number of bugs related to
sugov and the scheduler getting out of sync wrt this state.
As a consequence we not also update the remove cfs/dl state when
iterating the shared mask.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Due to using GCC defines for configuration, some labels might be unused in
certain configurations. While adding a __maybe_unused to the label is
fine in general, the line has to be terminated with ';'. This is also
reflected in the GCC documentation, but GCC parsed the previous variant
without an error message.
This has been spotted while compiling with goto-cc, the compiler for the
CPROVER tool suite.
Signed-off-by: Norbert Manthey <nmanthey@amazon.de>
Signed-off-by: Michael Tautschnig <tautschn@amazon.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1519717660-16157-1-git-send-email-nmanthey@amazon.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
otherwise kernel can oops later in seq_release() due to dereferencing null
file->private_data which is only set if seq_open() succeeds.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
IP: seq_release+0xc/0x30
Call Trace:
close_pdeo+0x37/0xd0
proc_reg_release+0x5d/0x60
__fput+0x9d/0x1d0
____fput+0x9/0x10
task_work_run+0x75/0x90
do_exit+0x252/0xa00
do_group_exit+0x36/0xb0
SyS_exit_group+0xf/0x10
Fixes: 516fb7f2e7 ("/proc/module: use the same logic as /proc/kallsyms for address exposure")
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org # 4.15+
Signed-off-by: Leon Yu <chianglungyu@gmail.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
This commit adds new field "addr" to bpf_perf_event_data which could be
read and used by bpf programs attached to perf events. The value of the
field is copied from bpf_perf_event_data_kern.addr and contains the
address value recorded by specifying sample_type with PERF_SAMPLE_ADDR
when calling perf_event_open.
Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
devm_memremap_pages() was re-worked in e8d5134833 "memremap: change
devm_memremap_pages interface to use struct dev_pagemap" to take a
caller allocated struct dev_pagemap as a function parameter. A call to
devres_free() was left in the error cleanup path which results in a
kernel panic if the remap fails for some reason. Remove it to fix the
panic and let devm_memremap_pages() fail gracefully.
Fixes: e8d5134833 ("memremap: change devm_memremap_pages interface...")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
All of the conflicts were cases of overlapping changes.
In net/core/devlink.c, we have to make care that the
resouce size_params have become a struct member rather
than a pointer to such an object.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Use an appropriate TSQ pacing shift in mac80211, from Toke
Høiland-Jørgensen.
2) Just like ipv4's ip_route_me_harder(), we have to use skb_to_full_sk
in ip6_route_me_harder, from Eric Dumazet.
3) Fix several shutdown races and similar other problems in l2tp, from
James Chapman.
4) Handle missing XDP flush properly in tuntap, for real this time.
From Jason Wang.
5) Out-of-bounds access in powerpc ebpf tailcalls, from Daniel
Borkmann.
6) Fix phy_resume() locking, from Andrew Lunn.
7) IFLA_MTU values are ignored on newlink for some tunnel types, fix
from Xin Long.
8) Revert F-RTO middle box workarounds, they only handle one dimension
of the problem. From Yuchung Cheng.
9) Fix socket refcounting in RDS, from Ka-Cheong Poon.
10) Don't allow ppp unit registration to an unregistered channel, from
Guillaume Nault.
11) Various hv_netvsc fixes from Stephen Hemminger.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (98 commits)
hv_netvsc: propagate rx filters to VF
hv_netvsc: filter multicast/broadcast
hv_netvsc: defer queue selection to VF
hv_netvsc: use napi_schedule_irqoff
hv_netvsc: fix race in napi poll when rescheduling
hv_netvsc: cancel subchannel setup before halting device
hv_netvsc: fix error unwind handling if vmbus_open fails
hv_netvsc: only wake transmit queue if link is up
hv_netvsc: avoid retry on send during shutdown
virtio-net: re enable XDP_REDIRECT for mergeable buffer
ppp: prevent unregistered channels from connecting to PPP units
tc-testing: skbmod: fix match value of ethertype
mlxsw: spectrum_switchdev: Check success of FDB add operation
net: make skb_gso_*_seglen functions private
net: xfrm: use skb_gso_validate_network_len() to check gso sizes
net: sched: tbf: handle GSO_BY_FRAGS case in enqueue
net: rename skb_gso_validate_mtu -> skb_gso_validate_network_len
rds: Incorrect reference counting in TCP socket creation
net: ethtool: don't ignore return from driver get_fecparam method
vrf: check forwarding on the original netdevice when generating ICMP dest unreachable
...
Pull timer fixes from Thomas Gleixner:
"A small set of fixes from the timer departement:
- Add a missing timer wheel clock forward when migrating timers off a
unplugged CPU to prevent operating on a stale clock base and
missing timer deadlines.
- Use the proper shift count to extract data from a register value to
prevent evaluating unrelated bits
- Make the error return check in the FSL timer driver work correctly.
Checking an unsigned variable for less than zero does not really
work well.
- Clarify the confusing comments in the ARC timer code"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers: Forward timer base before migrating timers
clocksource/drivers/arc_timer: Update some comments
clocksource/drivers/mips-gic-timer: Use correct shift count to extract data
clocksource/drivers/fsl_ftm_timer: Fix error return checking
Make it easier to concatenate all the scheduler .c files for single-module
compilation.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge these two small .c modules as they implement two aspects
of idle task handling.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Do the following cleanups and simplifications:
- sched/sched.h already includes <asm/paravirt.h>, so no need to
include it in sched/core.c again.
- order the <linux/sched/*.h> headers alphabetically
- add all <linux/sched/*.h> headers to kernel/sched/sched.h
- remove all unnecessary includes from the .c files that
are already included in kernel/sched/sched.h.
Finally, make all scheduler .c files use a single common header:
#include "sched.h"
... which now contains a union of the relied upon headers.
This makes the various .c files easier to read and easier to handle.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull libnvdimm fixes from Dan Williams:
"A 4.16 regression fix, three fixes for -stable, and a cleanup fix:
- During the merge window support for the new ACPI NVDIMM Platform
Capabilities structure disabled support for "deep flush", a
force-unit- access like mechanism for persistent memory. Restore
that mechanism.
- VFIO like RDMA is yet one more memory registration / pinning
interface that is incompatible with Filesystem-DAX. Disable long
term pins of Filesystem-DAX mappings via VFIO.
- The Filesystem-DAX detection to prevent long terms pins mistakenly
also disabled Device-DAX pins which are not subject to the same
block- map collision concerns.
- Similar to the setup path, softlockup warnings can trigger in the
shutdown path for large persistent memory namespaces. Teach
for_each_device_pfn() to perform cond_resched() in all cases.
- Boaz noticed that the might_sleep() in dax_direct_access() is stale
as of the v4.15 kernel.
These have received a build success notification from the 0day robot,
and the longterm pin fixes have appeared in -next. However, I recently
rebased the tree to remove some other fixes that need to be reworked
after review feedback.
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
memremap: fix softlockup reports at teardown
libnvdimm: re-enable deep flush for pmem devices via fsync()
vfio: disable filesystem-dax page pinning
dax: fix vma_is_fsdax() helper
dax: ->direct_access does not sleep anymore
A good number of small style inconsistencies have accumulated
in the scheduler core, so do a pass over them to harmonize
all these details:
- fix speling in comments,
- use curly braces for multi-line statements,
- remove unnecessary parentheses from integer literals,
- capitalize consistently,
- remove stray newlines,
- add comments where necessary,
- remove invalid/unnecessary comments,
- align structure definitions and other data types vertically,
- add missing newlines for increased readability,
- fix vertical tabulation where it's misaligned,
- harmonize preprocessor conditional block labeling
and vertical alignment,
- remove line-breaks where they uglify the code,
- add newline after local variable definitions,
No change in functionality:
md5:
1191fa0a890cfa8132156d2959d7e9e2 built-in.o.before.asm
1191fa0a890cfa8132156d2959d7e9e2 built-in.o.after.asm
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Fixed style error: Missing space before the open parenthesis
- Fixed style warnings: 2x Missing blank line after declaration
One warning left: else after return
(I don't feel comfortable fixing that without side effects)
Signed-off-by: Mario Leinweber <marioleinweber@web.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/20180302182007.28691-1-marioleinweber@web.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The cond_resched() currently in the setup path needs to be duplicated in
the teardown path. Rather than require each instance of
for_each_device_pfn() to open code the same sequence, embed it in the
helper.
Link: https://github.com/intel/ixpdimm_sw/issues/11
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Fixes: 7138970383 ("mm, zone_device: Replace {get, put}_zone_device_page()...")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Since commit afcc90f862 ("usercopy: WARN() on slab cache usercopy
region violations"), MIPS systems booting with a compat root filesystem
emit a warning when copying compat siginfo to userspace:
WARNING: CPU: 0 PID: 953 at mm/usercopy.c:81 usercopy_warn+0x98/0xe8
Bad or missing usercopy whitelist? Kernel memory exposure attempt
detected from SLAB object 'task_struct' (offset 1432, size 16)!
Modules linked in:
CPU: 0 PID: 953 Comm: S01logging Not tainted 4.16.0-rc2 #10
Stack : ffffffff808c0000 0000000000000000 0000000000000001 65ac85163f3bdc4a
65ac85163f3bdc4a 0000000000000000 90000000ff667ab8 ffffffff808c0000
00000000000003f8 ffffffff808d0000 00000000000000d1 0000000000000000
000000000000003c 0000000000000000 ffffffff808c8ca8 ffffffff808d0000
ffffffff808d0000 ffffffff80810000 fffffc0000000000 ffffffff80785c30
0000000000000009 0000000000000051 90000000ff667eb0 90000000ff667db0
000000007fe0d938 0000000000000018 ffffffff80449958 0000000020052798
ffffffff808c0000 90000000ff664000 90000000ff667ab0 00000000100c0000
ffffffff80698810 0000000000000000 0000000000000000 0000000000000000
0000000000000000 0000000000000000 ffffffff8010d02c 65ac85163f3bdc4a
...
Call Trace:
[<ffffffff8010d02c>] show_stack+0x9c/0x130
[<ffffffff80698810>] dump_stack+0x90/0xd0
[<ffffffff80137b78>] __warn+0x100/0x118
[<ffffffff80137bdc>] warn_slowpath_fmt+0x4c/0x70
[<ffffffff8021e4a8>] usercopy_warn+0x98/0xe8
[<ffffffff8021e68c>] __check_object_size+0xfc/0x250
[<ffffffff801bbfb8>] put_compat_sigset+0x30/0x88
[<ffffffff8011af24>] setup_rt_frame_n32+0xc4/0x160
[<ffffffff8010b8b4>] do_signal+0x19c/0x230
[<ffffffff8010c408>] do_notify_resume+0x60/0x78
[<ffffffff80106f50>] work_notifysig+0x10/0x18
---[ end trace 88fffbf69147f48a ]---
Commit 5905429ad8 ("fork: Provide usercopy whitelisting for
task_struct") noted that:
"While the blocked and saved_sigmask fields of task_struct are copied to
userspace (via sigmask_to_save() and setup_rt_frame()), it is always
copied with a static length (i.e. sizeof(sigset_t))."
However, this is not true in the case of compat signals, whose sigset
is copied by put_compat_sigset and receives size as an argument.
At most call sites, put_compat_sigset is copying a sigset from the
current task_struct. This triggers a warning when
CONFIG_HARDENED_USERCOPY is active. However, by marking this function as
static inline, the warning can be avoided because in all of these cases
the size is constant at compile time, which is allowed. The only site
where this is not the case is handling the rt_sigpending syscall, but
there the copy is being made from a stack local variable so does not
trigger the warning.
Move put_compat_sigset to compat.h, and mark it static inline. This
fixes the WARN on MIPS.
Fixes: afcc90f862 ("usercopy: WARN() on slab cache usercopy region violations")
Signed-off-by: Matt Redfearn <matt.redfearn@mips.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: "Dmitry V . Levin" <ldv@altlinux.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18639/
Signed-off-by: James Hogan <jhogan@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf 2018-02-28
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Add schedule points and reduce the number of loop iterations
the test_bpf kernel module is performing in order to not hog
the CPU for too long, from Eric.
2) Fix an out of bounds access in tail calls in the ppc64 BPF
JIT compiler, from Daniel.
3) Fix a crash on arm64 on unaligned BPF xadd operations that
could be triggered via interpreter and JIT, from Daniel.
Please not that once you merge net into net-next at some point, there
is a minor merge conflict in test_verifier.c since test cases had
been added at the end in both trees. Resolution is trivial: keep all
the test cases from both trees.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull printk fix from Petr Mladek:
"Make sure that we wake up userspace loggers. This fixes a race
introduced by the console waiter logic during this merge window"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
printk: Wake klogd when passing console_lock owner
On CPU hotunplug the enqueued timers of the unplugged CPU are migrated to a
live CPU. This happens from the control thread which initiated the unplug.
If the CPU on which the control thread runs came out from a longer idle
period then the base clock of that CPU might be stale because the control
thread runs prior to any event which forwards the clock.
In such a case the timers from the unplugged CPU are queued on the live CPU
based on the stale clock which can cause large delays due to increased
granularity of the outer timer wheels which are far away from base:;clock.
But there is a worse problem than that. The following sequence of events
illustrates it:
- CPU0 timer1 is queued expires = 59969 and base->clk = 59131.
The timer is queued at wheel level 2, with resulting expiry time = 60032
(due to level granularity).
- CPU1 enters idle @60007, with next timer expiry @60020.
- CPU0 is hotplugged at @60009
- CPU1 exits idle and runs the control thread which migrates the
timers from CPU0
timer1 is now queued in level 0 for immediate handling in the next
softirq because the requested expiry time 59969 is before CPU1 base->clk
60007
- CPU1 runs code which forwards the base clock which succeeds because the
next expiring timer. which was collected at idle entry time is still set
to 60020.
So it forwards beyond 60007 and therefore misses to expire the migrated
timer1. That timer gets expired when the wheel wraps around again, which
takes between 63 and 630ms depending on the HZ setting.
Address both problems by invoking forward_timer_base() for the control CPUs
timer base. All other places, which might run into a similar problem
(mod_timer()/add_timer_on()) already invoke forward_timer_base() to avoid
that.
[ tglx: Massaged comment and changelog ]
Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Co-developed-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: linux-arm-msm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180118115022.6368-1-clingutla@codeaurora.org
Show unadorned pointers in lockdep reports - lockdep is a debugging
facility and hashing pointers there doesn't make a whole lotta sense.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20180226134926.23069-1-bp@alien8.de
wake_klogd is a local variable in console_unlock(). The information
is lost when the console_lock owner using the busy wait added by
the commit dbdda842fe ("printk: Add console owner and waiter
logic to load balance console writes"). The following race is
possible:
CPU0 CPU1
console_unlock()
for (;;)
/* calling console for last message */
printk()
log_store()
log_next_seq++;
/* see new message */
if (seen_seq != log_next_seq) {
wake_klogd = true;
seen_seq = log_next_seq;
}
console_lock_spinning_enable();
if (console_trylock_spinning())
/* spinning */
if (console_lock_spinning_disable_and_check()) {
printk_safe_exit_irqrestore(flags);
return;
console_unlock()
if (seen_seq != log_next_seq) {
/* already seen */
/* nothing to do */
Result: Nobody would wakeup klogd.
One solution would be to make a global variable from wake_klogd.
But then we would need to manipulate it under a lock or so.
This patch wakes klogd also when console_lock is passed to the
spinning waiter. It looks like the right way to go. Also userspace
should have a chance to see and store any "flood" of messages.
Note that the very late klogd wake up was a historic solution.
It made sense on single CPU systems or when sys_syslog() operations
were synchronized using the big kernel lock like in v2.1.113.
But it is questionable these days.
Fixes: dbdda842fe ("printk: Add console owner and waiter logic to load balance console writes")
Link: http://lkml.kernel.org/r/20180226155734.dzwg3aovqnwtvkoy@pathway.suse.cz
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: Tejun Heo <tj@kernel.org>
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Pull x86 fixes from Thomas Gleixner:
"Yet another pile of melted spectrum related changes:
- sanitize the array_index_nospec protection mechanism: Remove the
overengineered array_index_nospec_mask_check() magic and allow
const-qualified types as index to avoid temporary storage in a
non-const local variable.
- make the microcode loader more robust by properly propagating error
codes. Provide information about new feature bits after micro code
was updated so administrators can act upon.
- optimizations of the entry ASM code which reduce code footprint and
make the code simpler and faster.
- fix the {pmd,pud}_{set,clear}_flags() implementations to work
properly on paravirt kernels by removing the address translation
operations.
- revert the harmful vmexit_fill_RSB() optimization
- use IBRS around firmware calls
- teach objtool about retpolines and add annotations for indirect
jumps and calls.
- explicitly disable jumplabel patching in __init code and handle
patching failures properly instead of silently ignoring them.
- remove indirect paravirt calls for writing the speculation control
MSR as these calls are obviously proving the same attack vector
which is tried to be mitigated.
- a few small fixes which address build issues with recent compiler
and assembler versions"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR path as unlikely()
KVM/x86: Remove indirect MSR op calls from SPEC_CTRL
objtool, retpolines: Integrate objtool with retpoline support more closely
x86/entry/64: Simplify ENCODE_FRAME_POINTER
extable: Make init_kernel_text() global
jump_label: Warn on failed jump_label patching attempt
jump_label: Explicitly disable jump labels in __init code
x86/entry/64: Open-code switch_to_thread_stack()
x86/entry/64: Move ASM_CLAC to interrupt_entry()
x86/entry/64: Remove 'interrupt' macro
x86/entry/64: Move the switch_to_thread_stack() call to interrupt_entry()
x86/entry/64: Move ENTER_IRQ_STACK from interrupt macro to interrupt_entry
x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function
x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP
objtool: Add module specific retpoline rules
objtool: Add retpoline validation
objtool: Use existing global variables for options
x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute()
x86/boot, objtool: Annotate indirect jump in secondary_startup_64()
x86/paravirt, objtool: Annotate indirect calls
...
Daniel Borkmann says:
====================
pull-request: bpf-next 2018-02-26
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Various improvements for BPF kselftests: i) skip unprivileged tests
when kernel.unprivileged_bpf_disabled sysctl knob is set, ii) count
the number of skipped tests from unprivileged, iii) when a test case
had an unexpected error then print the actual but also the unexpected
one for better comparison, from Joe.
2) Add a sample program for collecting CPU state statistics with regards
to how long the CPU resides in cstate and pstate levels. Based on
cpu_idle and cpu_frequency trace points, from Leo.
3) Various x64 BPF JIT optimizations to further shrink the generated
image size in order to make it more icache friendly. When tested on
the Cilium generated programs, image size reduced by approx 4-5% in
best case mainly due to how LLVM emits unsigned 32 bit constants,
from Daniel.
4) Improvements and fixes on the BPF sockmap sample programs: i) fix
the sockmap's Makefile to include nlattr.o for libbpf, ii) detach
the sock ops programs from the cgroup before exit, from Prashant.
5) Avoid including xdp.h in filter.h by just forward declaring the
struct xdp_rxq_info in filter.h, from Jesper.
6) Fix the BPF kselftests Makefile for cgroup_helpers.c by only declaring
it a dependency for test_dev_cgroup.c but not every other test case
where it is not needed, from Jesper.
7) Adjust rlimit RLIMIT_MEMLOCK for test_tcpbpf_user selftest since the
default is insufficient for creating the 'global_map' used in the
corresponding BPF program, from Yonghong.
8) Likewise, for the xdp_redirect sample, Tushar ran into the same when
invoking xdp_redirect and xdp_monitor at the same time, therefore
in order to have the sample generically work bump the limit here,
too. Fix from Tushar.
9) Avoid an unnecessary NULL check in BPF_CGROUP_RUN_PROG_INET_SOCK()
since sk is always guaranteed to be non-NULL, from Yafang.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull x86 fixes from Thomas Gleixner:
"A small set of fixes:
- UAPI data type correction for hyperv
- correct the cpu cores field in /proc/cpuinfo on CPU hotplug
- return proper error code in the resctrl file system failure path to
avoid silent subsequent failures
- correct a subtle accounting issue in the new vector allocation code
which went unnoticed for a while and caused suspend/resume
failures"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations
x86/topology: Fix function name in documentation
x86/intel_rdt: Fix incorrect returned value when creating rdgroup sub-directory in resctrl file system
x86/apic/vector: Handle vector release on CPU unplug correctly
genirq/matrix: Handle CPU offlining proper
x86/headers/UAPI: Use __u64 instead of u64 in <uapi/asm/hyperv.h>
RCU's expedited grace periods can participate in out-of-memory deadlocks
due to all available system_wq kthreads being blocked and there not being
memory available to create more. This commit prevents such deadlocks
by allocating an RCU-specific workqueue_struct at early boot time, and
providing it with a rescuer to ensure forward progress. This uses the
shiny new init_rescuer() function provided by Tejun (but indirectly).
This commit also causes SRCU to use this new RCU-specific
workqueue_struct. Note that SRCU's use of workqueues never blocks them
waiting for readers, so this should be safe from a forward-progress
viewpoint. Note that this moves SRCU from system_power_efficient_wq
to a normal workqueue. In the unlikely event that this results in
measurable degradation, a separate power-efficient workqueue will be
creates for SRCU.
Reported-by: Prateek Sood <prsood@codeaurora.org>
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Pull networking fixes from David Miller:
1) Fix TTL offset calculation in mac80211 mesh code, from Peter Oh.
2) Fix races with procfs in ipt_CLUSTERIP, from Cong Wang.
3) Memory leak fix in lpm_trie BPF map code, from Yonghong Song.
4) Need to use GFP_ATOMIC in BPF cpumap allocations, from Jason Wang.
5) Fix potential deadlocks in netfilter getsockopt() code paths, from
Paolo Abeni.
6) Netfilter stackpointer size checks really are needed to validate
user input, from Florian Westphal.
7) Missing timer init in x_tables, from Paolo Abeni.
8) Don't use WQ_MEM_RECLAIM in mac80211 hwsim, from Johannes Berg.
9) When an ibmvnic device is brought down then back up again, it can be
sent queue entries from a previous session, handle this properly
instead of crashing. From Thomas Falcon.
10) Fix TCP checksum on LRO buffers in mlx5e, from Gal Pressman.
11) When we are dumping filters in cls_api, the output SKB is empty, and
the filter we are dumping is too large for the space in the SKB, we
should return -EMSGSIZE like other netlink dump operations do.
Otherwise userland has no signal that is needs to increase the size
of its read buffer. From Roman Kapl.
12) Several XDP fixes for virtio_net, from Jesper Dangaard Brouer.
13) Module refcount leak in netlink when a dump start fails, from Jason
Donenfeld.
14) Handle sub-optimal GSO sizes better in TCP BBR congestion control,
from Eric Dumazet.
15) Releasing bpf per-cpu arraymaps can take a long time, add a
condtional scheduling point. From Eric Dumazet.
16) Implement retpolines for tail calls in x64 and arm64 bpf JITs. From
Daniel Borkmann.
17) Fix page leak in gianfar driver, from Andy Spencer.
18) Missed clearing of estimator scratch buffer, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
net_sched: gen_estimator: fix broken estimators based on percpu stats
gianfar: simplify FCS handling and fix memory leak
ipv6 sit: work around bogus gcc-8 -Wrestrict warning
macvlan: fix use-after-free in macvlan_common_newlink()
bpf, arm64: fix out of bounds access in tail call
bpf, x64: implement retpoline for tail call
rxrpc: Fix send in rxrpc_send_data_packet()
net: aquantia: Fix error handling in aq_pci_probe()
bpf: fix rcu lockdep warning for lpm_trie map_free callback
bpf: add schedule points in percpu arrays management
regulatory: add NUL to request alpha2
ibmvnic: Fix early release of login buffer
net/smc9194: Remove bogus CONFIG_MAC reference
net: ipv4: Set addr_type in hash_keys for forwarded case
tcp_bbr: better deal with suboptimal GSO
smsc75xx: fix smsc75xx_set_features()
netlink: put module reference if dump start fails
selftests/bpf/test_maps: exit child process without error in ENOMEM case
selftests/bpf: update gitignore with test_libbpf_open
selftests/bpf: tcpbpf_kern: use in6_* macros from glibc
..
Pull security subsystem fixes from James Morris:
- keys fixes via David Howells:
"A collection of fixes for Linux keyrings, mostly thanks to Eric
Biggers:
- Fix some PKCS#7 verification issues.
- Fix handling of unsupported crypto in X.509.
- Fix too-large allocation in big_key"
- Seccomp updates via Kees Cook:
"These are fixes for the get_metadata interface that landed during
-rc1. While the new selftest is strictly not a bug fix, I think
it's in the same spirit of avoiding bugs"
- an IMA build fix from Randy Dunlap
* 'fixes-v4.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
integrity/security: fix digsig.c build error with header file
KEYS: Use individual pages in big_key for crypto buffers
X.509: fix NULL dereference when restricting key with unsupported_sig
X.509: fix BUG_ON() when hash algorithm is unsupported
PKCS#7: fix direct verification of SignerInfo signature
PKCS#7: fix certificate blacklisting
PKCS#7: fix certificate chain verification
seccomp: add a selftest for get_metadata
ptrace, seccomp: tweak get_metadata behavior slightly
seccomp, ptrace: switch get_metadata types to arch independent
The requirements around atomic_add() / atomic64_add() resp. their
JIT implementations differ across architectures. E.g. while x86_64
seems just fine with BPF's xadd on unaligned memory, on arm64 it
triggers via interpreter but also JIT the following crash:
[ 830.864985] Unable to handle kernel paging request at virtual address ffff8097d7ed6703
[...]
[ 830.916161] Internal error: Oops: 96000021 [#1] SMP
[ 830.984755] CPU: 37 PID: 2788 Comm: test_verifier Not tainted 4.16.0-rc2+ #8
[ 830.991790] Hardware name: Huawei TaiShan 2280 /BC11SPCD, BIOS 1.29 07/17/2017
[ 830.998998] pstate: 80400005 (Nzcv daif +PAN -UAO)
[ 831.003793] pc : __ll_sc_atomic_add+0x4/0x18
[ 831.008055] lr : ___bpf_prog_run+0x1198/0x1588
[ 831.012485] sp : ffff00001ccabc20
[ 831.015786] x29: ffff00001ccabc20 x28: ffff8017d56a0f00
[ 831.021087] x27: 0000000000000001 x26: 0000000000000000
[ 831.026387] x25: 000000c168d9db98 x24: 0000000000000000
[ 831.031686] x23: ffff000008203878 x22: ffff000009488000
[ 831.036986] x21: ffff000008b14e28 x20: ffff00001ccabcb0
[ 831.042286] x19: ffff0000097b5080 x18: 0000000000000a03
[ 831.047585] x17: 0000000000000000 x16: 0000000000000000
[ 831.052885] x15: 0000ffffaeca8000 x14: 0000000000000000
[ 831.058184] x13: 0000000000000000 x12: 0000000000000000
[ 831.063484] x11: 0000000000000001 x10: 0000000000000000
[ 831.068783] x9 : 0000000000000000 x8 : 0000000000000000
[ 831.074083] x7 : 0000000000000000 x6 : 000580d428000000
[ 831.079383] x5 : 0000000000000018 x4 : 0000000000000000
[ 831.084682] x3 : ffff00001ccabcb0 x2 : 0000000000000001
[ 831.089982] x1 : ffff8097d7ed6703 x0 : 0000000000000001
[ 831.095282] Process test_verifier (pid: 2788, stack limit = 0x0000000018370044)
[ 831.102577] Call trace:
[ 831.105012] __ll_sc_atomic_add+0x4/0x18
[ 831.108923] __bpf_prog_run32+0x4c/0x70
[ 831.112748] bpf_test_run+0x78/0xf8
[ 831.116224] bpf_prog_test_run_xdp+0xb4/0x120
[ 831.120567] SyS_bpf+0x77c/0x1110
[ 831.123873] el0_svc_naked+0x30/0x34
[ 831.127437] Code: 97fffe97 17ffffec 00000000 f9800031 (885f7c31)
Reason for this is because memory is required to be aligned. In
case of BPF, we always enforce alignment in terms of stack access,
but not when accessing map values or packet data when the underlying
arch (e.g. arm64) has CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS set.
xadd on packet data that is local to us anyway is just wrong, so
forbid this case entirely. The only place where xadd makes sense in
fact are map values; xadd on stack is wrong as well, but it's been
around for much longer. Specifically enforce strict alignment in case
of xadd, so that we handle this case generically and avoid such crashes
in the first place.
Fixes: 17a5267067 ("bpf: verifier (add verifier core)")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Merge tag 'drm-fixes-for-v4.16-rc3' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"A bunch of fixes for rc3:
Exynos:
- fixes for using monotonic timestamps
- register definitions
- removal of unused file
ipu-v3L
- minor changes
- make some register arrays const+static
- fix some leaks
meson:
- fix for vsync
atomic:
- fix for memory leak
EDID parser:
- add quirks for some more non-desktop devices
- 6-bit panel fix.
drm_mm:
- fix a bug in the core drm mm hole handling
cirrus:
- fix lut loading regression
Lastly there is a deadlock fix around runtime suspend for secondary
GPUs.
There was a deadlock between one thread trying to wait for a workqueue
job to finish in the runtime suspend path, and the workqueue job it
was waiting for in turn waiting for a runtime_get_sync to return.
The fixes avoids it by not doing the runtime sync in the workqueue as
then we always wait for all those tasks to complete before we runtime
suspend"
* tag 'drm-fixes-for-v4.16-rc3' of git://people.freedesktop.org/~airlied/linux: (25 commits)
drm/tve200: fix kernel-doc documentation comment include
drm/edid: quirk Sony PlayStation VR headset as non-desktop
drm/edid: quirk Windows Mixed Reality headsets as non-desktop
drm/edid: quirk Oculus Rift headsets as non-desktop
drm/meson: fix vsync buffer update
drm: Handle unexpected holes in color-eviction
drm: exynos: Use proper macro definition for HDMI_I2S_PIN_SEL_1
drm/exynos: remove exynos_drm_rotator.h
drm/exynos: g2d: Delete an error message for a failed memory allocation in two functions
drm/exynos: fix comparison to bitshift when dealing with a mask
drm/exynos: g2d: use monotonic timestamps
drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
gpu: ipu-csi: add 10/12-bit grayscale support to mbus_code_to_bus_cfg
gpu: ipu-cpmem: add 16-bit grayscale support to ipu_cpmem_set_image
gpu: ipu-v3: prg: fix device node leak in ipu_prg_lookup_by_phandle
gpu: ipu-v3: pre: fix device node leak in ipu_pre_lookup_by_phandle
drm/amdgpu: Fix deadlock on runtime suspend
drm/radeon: Fix deadlock on runtime suspend
drm/nouveau: Fix deadlock on runtime suspend
drm: Allow determining if current task is output poll worker
...
At CPU hotunplug the corresponding per cpu matrix allocator is shut down and
the allocated interrupt bits are discarded under the assumption that all
allocated bits have been either migrated away or shut down through the
managed interrupts mechanism.
This is not true because interrupts which are not started up might have a
vector allocated on the outgoing CPU. When the interrupt is started up
later or completely shutdown and freed then the allocated vector is handed
back, triggering warnings or causing accounting issues which result in
suspend failures and other issues.
Change the CPU hotplug mechanism of the matrix allocator so that the
remaining allocations at unplug time are preserved and global accounting at
hotplug is correctly readjusted to take the dormant vectors into account.
Fixes: 2f75d9e1c9 ("genirq: Implement bitmap matrix allocator")
Reported-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180222112316.849980972@linutronix.de
Commit 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
fixed a memory leak and removed unnecessary locks in map_free callback function.
Unfortrunately, it introduced a lockdep warning. When lockdep checking is turned on,
running tools/testing/selftests/bpf/test_lpm_map will have:
[ 98.294321] =============================
[ 98.294807] WARNING: suspicious RCU usage
[ 98.295359] 4.16.0-rc2+ #193 Not tainted
[ 98.295907] -----------------------------
[ 98.296486] /home/yhs/work/bpf/kernel/bpf/lpm_trie.c:572 suspicious rcu_dereference_check() usage!
[ 98.297657]
[ 98.297657] other info that might help us debug this:
[ 98.297657]
[ 98.298663]
[ 98.298663] rcu_scheduler_active = 2, debug_locks = 1
[ 98.299536] 2 locks held by kworker/2:1/54:
[ 98.300152] #0: ((wq_completion)"events"){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0
[ 98.301381] #1: ((work_completion)(&map->work)){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0
Since actual trie tree removal happens only after no other
accesses to the tree are possible, replacing
rcu_dereference_protected(*slot, lockdep_is_held(&trie->lock))
with
rcu_dereference_protected(*slot, 1)
fixed the issue.
Fixes: 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
Reported-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
syszbot managed to trigger RCU detected stalls in
bpf_array_free_percpu()
It takes time to allocate a huge percpu map, but even more time to free
it.
Since we run in process context, use cond_resched() to yield cpu if
needed.
Fixes: a10423b87a ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Merge misc fixes from Andrew Morton:
"16 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: don't defer struct page initialization for Xen pv guests
lib/Kconfig.debug: enable RUNTIME_TESTING_MENU
vmalloc: fix __GFP_HIGHMEM usage for vmalloc_32 on 32b systems
selftests/memfd: add run_fuse_test.sh to TEST_FILES
bug.h: work around GCC PR82365 in BUG()
mm/swap.c: make functions and their kernel-doc agree (again)
mm/zpool.c: zpool_evictable: fix mismatch in parameter name and kernel-doc
ida: do zeroing in ida_pre_get()
mm, swap, frontswap: fix THP swap if frontswap enabled
certs/blacklist_nohashes.c: fix const confusion in certs blacklist
kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
mm, mlock, vmscan: no more skipping pagevecs
mm: memcontrol: fix NR_WRITEBACK leak in memcg and system stats
Kbuild: always define endianess in kconfig.h
include/linux/sched/mm.h: re-inline mmdrop()
tools: fix cross-compile var clobbering
Each read from a file in efivarfs results in two calls to EFI
(one to get the file size, another to get the actual data).
On X86 these EFI calls result in broadcast system management
interrupts (SMI) which affect performance of the whole system.
A malicious user can loop performing reads from efivarfs bringing
the system to its knees.
Linus suggested per-user rate limit to solve this.
So we add a ratelimit structure to "user_struct" and initialize
it for the root user for no limit. When allocating user_struct for
other users we set the limit to 100 per second. This could be used
for other places that want to limit the rate of some detrimental
user action.
In efivarfs if the limit is exceeded when reading, we take an
interruptible nap for 50ms and check the rate limit again.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Previously if users passed a small size for the input structure size, they
would get get odd behavior. It doesn't make sense to pass a structure
smaller than at least filter_off size, so let's just give -EINVAL in this
case.
This changes userspace visible behavior, but was only introduced in commit
26500475ac ("ptrace, seccomp: add support for retrieving seccomp
metadata") in 4.16-rc2, so should be safe to change if merged before then.
Reported-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
CC: Kees Cook <keescook@chromium.org>
CC: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
chan->n_subbufs is set by the user and relay_create_buf() does a kmalloc()
of chan->n_subbufs * sizeof(size_t *).
kmalloc_slab() will generate a warning when this fails if
chan->subbufs * sizeof(size_t *) > KMALLOC_MAX_SIZE.
Limit chan->n_subbufs to the maximum allowed kmalloc() size.
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802061216100.122576@chino.kir.corp.google.com
Fixes: f6302f1bcd ("relay: prevent integer overflow in relay_open()")
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As Peter points out, Doing a CALL+RET for just the decrement is a bit silly.
Fixes: d70f2a14b7 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc")
Acked-by: Peter Zijlstra (Intel) <peterz@infraded.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.
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Merge tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.
* tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc:
drm/tve200: fix kernel-doc documentation comment include
drm/meson: fix vsync buffer update
drm: Handle unexpected holes in color-eviction
drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
drm/amdgpu: Fix deadlock on runtime suspend
drm/radeon: Fix deadlock on runtime suspend
drm/nouveau: Fix deadlock on runtime suspend
drm: Allow determining if current task is output poll worker
workqueue: Allow retrieval of current task's work struct
drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits
Daniel Borkmann says:
====================
pull-request: bpf 2018-02-20
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix a memory leak in LPM trie's map_free() callback function, where
the trie structure itself was not freed since initial implementation.
Also a synchronize_rcu() was needed in order to wait for outstanding
programs accessing the trie to complete, from Yonghong.
2) Fix sock_map_alloc()'s error path in order to correctly propagate
the -EINVAL error in case of too large allocation requests. This
was just recently introduced when fixing close hooks via ULP layer,
fix from Eric.
3) Do not use GFP_ATOMIC in __cpu_map_entry_alloc(). Reason is that this
will not work with the recent __ptr_ring_init_queue_alloc() conversion
to kvmalloc_array(), where in case of fallback to vmalloc() that GFP
flag is invalid, from Jason.
4) Fix two recent syzkaller warnings: i) fix bpf_prog_array_copy_to_user()
when a prog query with a big number of ids was performed where we'd
otherwise trigger a warning from allocator side, ii) fix a missing
mlock precharge on arraymaps, from Daniel.
5) Two fixes for bpftool in order to avoid breaking JSON output when used
in batch mode, from Quentin.
6) Move a pr_debug() in libbpf in order to avoid having an otherwise
uninitialized variable in bpf_program__reloc_text(), from Jeremy.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
A domain cgroup isn't allowed to be turned threaded if its subtree is
populated or domain controllers are enabled. cgroup_enable_threaded()
depended on cgroup_can_be_thread_root() test to enforce this rule. A
parent which has populated domain descendants or have domain
controllers enabled can't become a thread root, so the above rules are
enforced automatically.
However, for the root cgroup which can host mixed domain and threaded
children, cgroup_can_be_thread_root() doesn't check any of those
conditions and thus first level cgroups ends up escaping those rules.
This patch fixes the bug by adding explicit checks for those rules in
cgroup_enable_threaded().
Reported-by: Michael Kerrisk (man-pages) <mtk.manpages@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: 8cfd8147df ("cgroup: implement cgroup v2 thread support")
Cc: stable@vger.kernel.org # v4.14+
Convert init_kernel_text() to a global function and use it in a few
places instead of manually comparing _sinittext and _einittext.
Note that kallsyms.h has a very similar function called
is_kernel_inittext(), but its end check is inclusive. I'm not sure
whether that's intentional behavior, so I didn't touch it.
Suggested-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently when the jump label code encounters an address which isn't
recognized by kernel_text_address(), it just silently fails.
This can be dangerous because jump labels are used in a variety of
places, and are generally expected to work. Convert the silent failure
to a warning.
This won't warn about attempted writes to tracepoints in __init code
after initmem has been freed, as those are already guarded by the
entry->code check.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/de3a271c93807adb7ed48f4e946b4f9156617680.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After initmem has been freed, any jump labels in __init code are
prevented from being written to by the kernel_text_address() check in
__jump_label_update(). However, this check is quite broad. If
kernel_text_address() were to return false for any other reason, the
jump label write would fail silently with no warning.
For jump labels in module init code, entry->code is set to zero to
indicate that the entry is disabled. Do the same thing for core kernel
init code. This makes the behavior more consistent, and will also make
it more straightforward to detect non-init jump label write failures in
the next patch.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/c52825c73f3a174e8398b6898284ec20d4deb126.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that the 1Hz tick is offloaded to workqueues, we can safely remove
the residual code that used to handle it locally.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1519186649-3242-7-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a CPU runs in full dynticks mode, a 1Hz tick remains in order to
keep the scheduler stats alive. However this residual tick is a burden
for bare metal tasks that can't stand any interruption at all, or want
to minimize them.
The usual boot parameters "nohz_full=" or "isolcpus=nohz" will now
outsource these scheduler ticks to the global workqueue so that a
housekeeping CPU handles those remotely. The sched_class::task_tick()
implementations have been audited and look safe to be called remotely
as the target runqueue and its current task are passed in parameter
and don't seem to be accessed locally.
Note that in the case of using isolcpus, it's still up to the user to
affine the global workqueues to the housekeeping CPUs through
/sys/devices/virtual/workqueue/cpumask or domains isolation
"isolcpus=nohz,domain".
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1519186649-3242-6-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As we prepare for offloading the residual 1hz scheduler ticks to
workqueue, let's affine those to housekeepers so that they don't
interrupt the CPUs that don't want to be disturbed.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1519186649-3242-5-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This check is racy but provides a good heuristic to determine whether
a CPU may need a remote tick or not.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1519186649-3242-4-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It makes this function more self-explanatory about what it does and how
to use it.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1519186649-3242-3-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Do that rename in order to normalize the hrtick namespace.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1519186649-3242-2-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If wake_affine() pulls a task to another node for any reason and the node is
no longer preferred then temporarily stop automatic NUMA balancing pulling
the task back. Otherwise, tasks with a strong waker/wakee relationship
may constantly fight automatic NUMA balancing over where a task should
be placed.
Once again netperf is interesting here. The performance barely changes
but automatic NUMA balancing is interesting:
Hmean send-64 354.67 ( 0.00%) 352.15 ( -0.71%)
Hmean send-128 702.91 ( 0.00%) 693.84 ( -1.29%)
Hmean send-256 1350.07 ( 0.00%) 1344.19 ( -0.44%)
Hmean send-1024 5124.38 ( 0.00%) 4941.24 ( -3.57%)
Hmean send-2048 9687.44 ( 0.00%) 9624.45 ( -0.65%)
Hmean send-3312 14577.64 ( 0.00%) 14514.35 ( -0.43%)
Hmean send-4096 16393.62 ( 0.00%) 16488.30 ( 0.58%)
Hmean send-8192 26877.26 ( 0.00%) 26431.63 ( -1.66%)
Hmean send-16384 38683.43 ( 0.00%) 38264.91 ( -1.08%)
Hmean recv-64 354.67 ( 0.00%) 352.15 ( -0.71%)
Hmean recv-128 702.91 ( 0.00%) 693.84 ( -1.29%)
Hmean recv-256 1350.07 ( 0.00%) 1344.19 ( -0.44%)
Hmean recv-1024 5124.38 ( 0.00%) 4941.24 ( -3.57%)
Hmean recv-2048 9687.43 ( 0.00%) 9624.45 ( -0.65%)
Hmean recv-3312 14577.59 ( 0.00%) 14514.35 ( -0.43%)
Hmean recv-4096 16393.55 ( 0.00%) 16488.20 ( 0.58%)
Hmean recv-8192 26876.96 ( 0.00%) 26431.29 ( -1.66%)
Hmean recv-16384 38682.41 ( 0.00%) 38263.94 ( -1.08%)
NUMA alloc hit 1465986 1423090
NUMA alloc miss 0 0
NUMA interleave hit 0 0
NUMA alloc local 1465897 1423003
NUMA base PTE updates 1473 1420
NUMA huge PMD updates 0 0
NUMA page range updates 1473 1420
NUMA hint faults 1383 1312
NUMA hint local faults 451 124
NUMA hint local percent 32 9
There is a slight degrading in performance but there are slightly fewer
NUMA faults. There is a large drop in the percentage of local faults but
the bulk of migrations for netperf are in small shared libraries so it's
reflecting the fact that automatic NUMA balancing has backed off. This is
a case where despite wake_affine() and automatic NUMA balancing fighting
for placement that there is a marginal benefit to rescheduling to local
data quickly. However, it should be noted that wake_affine() and automatic
NUMA balancing fighting each other constantly is undesirable.
However, the benefit in other cases is large. This is the result for NAS
with the D class sizing on a 4-socket machine:
nas-mpi
4.15.0 4.15.0
sdnuma-v1r23 delayretry-v1r23
Time cg.D 557.00 ( 0.00%) 431.82 ( 22.47%)
Time ep.D 77.83 ( 0.00%) 79.01 ( -1.52%)
Time is.D 26.46 ( 0.00%) 26.64 ( -0.68%)
Time lu.D 727.14 ( 0.00%) 597.94 ( 17.77%)
Time mg.D 191.35 ( 0.00%) 146.85 ( 23.26%)
4.15.0 4.15.0
sdnuma-v1r23delayretry-v1r23
User 75665.20 70413.30
System 20321.59 8861.67
Elapsed 766.13 634.92
Minor Faults 16528502 7127941
Major Faults 4553 5068
NUMA alloc local 6963197 6749135
NUMA base PTE updates 366409093 107491434
NUMA huge PMD updates 687556 198880
NUMA page range updates 718437765 209317994
NUMA hint faults 13643410 4601187
NUMA hint local faults 9212593 3063996
NUMA hint local percent 67 66
Note the massive reduction in system CPU usage even though the percentage
of local faults is barely affected. There is a massive reduction in the
number of PTE updates showing that automatic NUMA balancing has backed off.
A critical observation is also that there is a massive reduction in minor
faults which is due to far fewer NUMA hinting faults being trapped.
There were questions on NAS OMP and how it behaved related to threads
being bound to CPUs. First, there are more gains than losses with this
patch applied and a reduction in system CPU usage:
nas-omp
4.16.0-rc1 4.16.0-rc1
sdnuma-v2r1 delayretry-v2r1
Time bt.D 436.71 ( 0.00%) 430.05 ( 1.53%)
Time cg.D 201.02 ( 0.00%) 180.87 ( 10.02%)
Time ep.D 32.84 ( 0.00%) 32.68 ( 0.49%)
Time is.D 9.63 ( 0.00%) 9.64 ( -0.10%)
Time lu.D 331.20 ( 0.00%) 304.80 ( 7.97%)
Time mg.D 54.87 ( 0.00%) 52.72 ( 3.92%)
Time sp.D 1108.78 ( 0.00%) 917.10 ( 17.29%)
Time ua.D 378.81 ( 0.00%) 398.83 ( -5.28%)
4.16.0-rc1 4.16.0-rc1
sdnuma-v2r1delayretry-v2r1
User 305633.08 296751.91
System 451.75 357.80
Elapsed 2595.73 2368.13
However, it does not close the gap between binding and being unbound. There
is negligible difference between the performance of the baseline and a
patched kernel when threads are bound so it is not presented here:
4.16.0-rc1 4.16.0-rc1
delayretry-bind delayretry-unbound
Time bt.D 385.02 ( 0.00%) 430.05 ( -11.70%)
Time cg.D 144.02 ( 0.00%) 180.87 ( -25.59%)
Time ep.D 32.85 ( 0.00%) 32.68 ( 0.52%)
Time is.D 10.52 ( 0.00%) 9.64 ( 8.37%)
Time lu.D 285.31 ( 0.00%) 304.80 ( -6.83%)
Time mg.D 43.21 ( 0.00%) 52.72 ( -22.01%)
Time sp.D 820.24 ( 0.00%) 917.10 ( -11.81%)
Time ua.D 337.09 ( 0.00%) 398.83 ( -18.32%)
4.16.0-rc1 4.16.0-rc1
delayretry-binddelayretry-unbound
User 277731.25 296751.91
System 261.29 357.80
Elapsed 2100.55 2368.13
Unfortunately, while performance is improved by the patch, there is still
quite a long way to go before it's equivalent to hard binding.
Other workloads like hackbench, tbench, dbench and schbench are barely
affected. dbench shows a mix of gains and losses depending on the machine
although in general, the results are more stable.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Giovanni Gherdovich <ggherdovich@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180213133730.24064-7-mgorman@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
find_idlest_group() compares a local group with each other group to select
the one that is most idle. When comparing groups in different NUMA domains,
a very slight imbalance is enough to select a remote NUMA node even if the
runnable load on both groups is 0 or close to 0. This ignores the cost of
remote accesses entirely and is a problem when selecting the CPU for a
newly forked task to run on. This is problematic when a forking server
is almost guaranteed to run on a remote node incurring numerous remote
accesses and potentially causing automatic NUMA balancing to try migrate
the task back or migrate the data to another node. Similar weirdness is
observed if a basic shell command pipes output to another as each process
in the pipeline is likely to start on different nodes and then get adjusted
later by wake_affine().
This patch adds imbalance to remote domains when considering whether to
select CPUs from remote domains. If the local domain is selected, imbalance
will still be used to try select a CPU from a lower scheduler domain's group
instead of stacking tasks on the same CPU.
A variety of workloads and machines were tested and as expected, there is no
difference on UMA. The difference on NUMA can be dramatic. This is a comparison
of elapsed times running the git regression test suite. It's fork-intensive with
short-lived processes:
4.15.0 4.15.0
noexit-v1r23 sdnuma-v1r23
Elapsed min 1706.06 ( 0.00%) 1435.94 ( 15.83%)
Elapsed mean 1709.53 ( 0.00%) 1436.98 ( 15.94%)
Elapsed stddev 2.16 ( 0.00%) 1.01 ( 53.38%)
Elapsed coeffvar 0.13 ( 0.00%) 0.07 ( 44.54%)
Elapsed max 1711.59 ( 0.00%) 1438.01 ( 15.98%)
4.15.0 4.15.0
noexit-v1r23 sdnuma-v1r23
User 5434.12 5188.41
System 4878.77 3467.09
Elapsed 10259.06 8624.21
That shows a considerable reduction in elapsed times. It's important to
note that automatic NUMA balancing does not affect this load as processes
are too short-lived.
There is also a noticable impact on hackbench such as this example using
processes and pipes:
hackbench-process-pipes
4.15.0 4.15.0
noexit-v1r23 sdnuma-v1r23
Amean 1 1.0973 ( 0.00%) 0.9393 ( 14.40%)
Amean 4 1.3427 ( 0.00%) 1.3730 ( -2.26%)
Amean 7 1.4233 ( 0.00%) 1.6670 ( -17.12%)
Amean 12 3.0250 ( 0.00%) 3.3013 ( -9.13%)
Amean 21 9.0860 ( 0.00%) 9.5343 ( -4.93%)
Amean 30 14.6547 ( 0.00%) 13.2433 ( 9.63%)
Amean 48 22.5447 ( 0.00%) 20.4303 ( 9.38%)
Amean 79 29.2010 ( 0.00%) 26.7853 ( 8.27%)
Amean 110 36.7443 ( 0.00%) 35.8453 ( 2.45%)
Amean 141 45.8533 ( 0.00%) 42.6223 ( 7.05%)
Amean 172 55.1317 ( 0.00%) 50.6473 ( 8.13%)
Amean 203 64.4420 ( 0.00%) 58.3957 ( 9.38%)
Amean 234 73.2293 ( 0.00%) 67.1047 ( 8.36%)
Amean 265 80.5220 ( 0.00%) 75.7330 ( 5.95%)
Amean 296 88.7567 ( 0.00%) 82.1533 ( 7.44%)
It's not a universal win as there are occasions when spreading wide and
quickly is a benefit but it's more of a win than it is a loss. For other
workloads, there is little difference but netperf is interesting. Without
the patch, the server and client starts on different nodes but quickly get
migrated due to wake_affine. Hence, the difference is overall performance
is marginal but detectable:
4.15.0 4.15.0
noexit-v1r23 sdnuma-v1r23
Hmean send-64 349.09 ( 0.00%) 354.67 ( 1.60%)
Hmean send-128 699.16 ( 0.00%) 702.91 ( 0.54%)
Hmean send-256 1316.34 ( 0.00%) 1350.07 ( 2.56%)
Hmean send-1024 5063.99 ( 0.00%) 5124.38 ( 1.19%)
Hmean send-2048 9705.19 ( 0.00%) 9687.44 ( -0.18%)
Hmean send-3312 14359.48 ( 0.00%) 14577.64 ( 1.52%)
Hmean send-4096 16324.20 ( 0.00%) 16393.62 ( 0.43%)
Hmean send-8192 26112.61 ( 0.00%) 26877.26 ( 2.93%)
Hmean send-16384 37208.44 ( 0.00%) 38683.43 ( 3.96%)
Hmean recv-64 349.09 ( 0.00%) 354.67 ( 1.60%)
Hmean recv-128 699.16 ( 0.00%) 702.91 ( 0.54%)
Hmean recv-256 1316.34 ( 0.00%) 1350.07 ( 2.56%)
Hmean recv-1024 5063.99 ( 0.00%) 5124.38 ( 1.19%)
Hmean recv-2048 9705.16 ( 0.00%) 9687.43 ( -0.18%)
Hmean recv-3312 14359.42 ( 0.00%) 14577.59 ( 1.52%)
Hmean recv-4096 16323.98 ( 0.00%) 16393.55 ( 0.43%)
Hmean recv-8192 26111.85 ( 0.00%) 26876.96 ( 2.93%)
Hmean recv-16384 37206.99 ( 0.00%) 38682.41 ( 3.97%)
However, what is very interesting is how automatic NUMA balancing behaves.
Each netperf instance runs long enough for balancing to activate:
NUMA base PTE updates 4620 1473
NUMA huge PMD updates 0 0
NUMA page range updates 4620 1473
NUMA hint faults 4301 1383
NUMA hint local faults 1309 451
NUMA hint local percent 30 32
NUMA pages migrated 1335 491
AutoNUMA cost 21% 6%
There is an unfortunate number of remote faults although tracing indicated
that the vast majority are in shared libraries. However, the tendency to
start tasks on the same node if there is capacity means that there were
far fewer PTE updates and faults incurred overall.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Giovanni Gherdovich <ggherdovich@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180213133730.24064-6-mgorman@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a task exits, it notifies the parent that it has exited. This is a
sync wakeup and the exiting task may pull the parent towards the wakers
CPU. For simple workloads like using a shell, it was observed that the
shell is pulled across nodes by exiting processes. This is daft as the
parent may be long-lived and properly placed. This patch special cases a
sync wakeup on exit to avoid pulling tasks across nodes. Testing on a range
of workloads and machines showed very little differences in performance
although there was a small 3% boost on some machines running a shellscript
intensive workload (git regression test suite).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Giovanni Gherdovich <ggherdovich@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180213133730.24064-5-mgorman@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
wake_affine_weight() will consider migrating a task to, or near, the current
CPU if there is a load imbalance. If the CPUs share LLC then either CPU
is valid as a search-for-idle-sibling target and equally appropriate for
stacking two tasks on one CPU if an idle sibling is unavailable. If they do
not share cache then a cross-node migration potentially impacts locality
so while they are equal from a CPU capacity point of view, they are not
equal in terms of memory locality. In either case, it's more appropriate
to migrate only if there is a difference in their effective load.
This patch modifies wake_affine_weight() to only consider migrating a task
if there is a load imbalance for normal wakeups but will allow potential
stacking if the loads are equal and it's a sync wakeup.
For the most part, the different in performance is marginal. For example,
on a 4-socket server running netperf UDP_STREAM on localhost the differences
are as follows:
4.15.0 4.15.0
16rc0 noequal-v1r23
Hmean send-64 355.47 ( 0.00%) 349.50 ( -1.68%)
Hmean send-128 697.98 ( 0.00%) 693.35 ( -0.66%)
Hmean send-256 1328.02 ( 0.00%) 1318.77 ( -0.70%)
Hmean send-1024 5051.83 ( 0.00%) 5051.11 ( -0.01%)
Hmean send-2048 9637.02 ( 0.00%) 9601.34 ( -0.37%)
Hmean send-3312 14355.37 ( 0.00%) 14414.51 ( 0.41%)
Hmean send-4096 16464.97 ( 0.00%) 16301.37 ( -0.99%)
Hmean send-8192 26722.42 ( 0.00%) 26428.95 ( -1.10%)
Hmean send-16384 38137.81 ( 0.00%) 38046.11 ( -0.24%)
Hmean recv-64 355.47 ( 0.00%) 349.50 ( -1.68%)
Hmean recv-128 697.98 ( 0.00%) 693.35 ( -0.66%)
Hmean recv-256 1328.02 ( 0.00%) 1318.77 ( -0.70%)
Hmean recv-1024 5051.83 ( 0.00%) 5051.11 ( -0.01%)
Hmean recv-2048 9636.95 ( 0.00%) 9601.30 ( -0.37%)
Hmean recv-3312 14355.32 ( 0.00%) 14414.48 ( 0.41%)
Hmean recv-4096 16464.74 ( 0.00%) 16301.16 ( -0.99%)
Hmean recv-8192 26721.63 ( 0.00%) 26428.17 ( -1.10%)
Hmean recv-16384 38136.00 ( 0.00%) 38044.88 ( -0.24%)
Stddev send-64 7.30 ( 0.00%) 4.75 ( 34.96%)
Stddev send-128 15.15 ( 0.00%) 22.38 ( -47.66%)
Stddev send-256 13.99 ( 0.00%) 19.14 ( -36.81%)
Stddev send-1024 105.73 ( 0.00%) 67.38 ( 36.27%)
Stddev send-2048 294.57 ( 0.00%) 223.88 ( 24.00%)
Stddev send-3312 302.28 ( 0.00%) 271.74 ( 10.10%)
Stddev send-4096 195.92 ( 0.00%) 121.10 ( 38.19%)
Stddev send-8192 399.71 ( 0.00%) 563.77 ( -41.04%)
Stddev send-16384 1163.47 ( 0.00%) 1103.68 ( 5.14%)
Stddev recv-64 7.30 ( 0.00%) 4.75 ( 34.96%)
Stddev recv-128 15.15 ( 0.00%) 22.38 ( -47.66%)
Stddev recv-256 13.99 ( 0.00%) 19.14 ( -36.81%)
Stddev recv-1024 105.73 ( 0.00%) 67.38 ( 36.27%)
Stddev recv-2048 294.59 ( 0.00%) 223.89 ( 24.00%)
Stddev recv-3312 302.24 ( 0.00%) 271.75 ( 10.09%)
Stddev recv-4096 196.03 ( 0.00%) 121.14 ( 38.20%)
Stddev recv-8192 399.86 ( 0.00%) 563.65 ( -40.96%)
Stddev recv-16384 1163.79 ( 0.00%) 1103.86 ( 5.15%)
The difference in overall performance is marginal but note that most
measurements are less variable. There were similar observations for other
netperf comparisons. hackbench with sockets or threads with processes or
threads showed minor difference with some reduction of migration. tbench
showed only marginal differences that were within the noise. dbench,
regardless of filesystem, showed minor differences all of which are
within noise. Multiple machines, both UMA and NUMA were tested without
any regressions showing up.
The biggest risk with a patch like this is affecting wakeup latencies.
However, the schbench load from Facebook which is very sensitive to wakeup
latency showed a mixed result with mostly improvements in wakeup latency:
4.15.0 4.15.0
16rc0 noequal-v1r23
Lat 50.00th-qrtle-1 38.00 ( 0.00%) 38.00 ( 0.00%)
Lat 75.00th-qrtle-1 49.00 ( 0.00%) 41.00 ( 16.33%)
Lat 90.00th-qrtle-1 52.00 ( 0.00%) 50.00 ( 3.85%)
Lat 95.00th-qrtle-1 54.00 ( 0.00%) 51.00 ( 5.56%)
Lat 99.00th-qrtle-1 63.00 ( 0.00%) 60.00 ( 4.76%)
Lat 99.50th-qrtle-1 66.00 ( 0.00%) 61.00 ( 7.58%)
Lat 99.90th-qrtle-1 78.00 ( 0.00%) 65.00 ( 16.67%)
Lat 50.00th-qrtle-2 38.00 ( 0.00%) 38.00 ( 0.00%)
Lat 75.00th-qrtle-2 42.00 ( 0.00%) 43.00 ( -2.38%)
Lat 90.00th-qrtle-2 46.00 ( 0.00%) 48.00 ( -4.35%)
Lat 95.00th-qrtle-2 49.00 ( 0.00%) 50.00 ( -2.04%)
Lat 99.00th-qrtle-2 55.00 ( 0.00%) 57.00 ( -3.64%)
Lat 99.50th-qrtle-2 58.00 ( 0.00%) 60.00 ( -3.45%)
Lat 99.90th-qrtle-2 65.00 ( 0.00%) 68.00 ( -4.62%)
Lat 50.00th-qrtle-4 41.00 ( 0.00%) 41.00 ( 0.00%)
Lat 75.00th-qrtle-4 45.00 ( 0.00%) 46.00 ( -2.22%)
Lat 90.00th-qrtle-4 50.00 ( 0.00%) 50.00 ( 0.00%)
Lat 95.00th-qrtle-4 54.00 ( 0.00%) 53.00 ( 1.85%)
Lat 99.00th-qrtle-4 61.00 ( 0.00%) 61.00 ( 0.00%)
Lat 99.50th-qrtle-4 65.00 ( 0.00%) 64.00 ( 1.54%)
Lat 99.90th-qrtle-4 76.00 ( 0.00%) 82.00 ( -7.89%)
Lat 50.00th-qrtle-8 48.00 ( 0.00%) 46.00 ( 4.17%)
Lat 75.00th-qrtle-8 55.00 ( 0.00%) 54.00 ( 1.82%)
Lat 90.00th-qrtle-8 60.00 ( 0.00%) 59.00 ( 1.67%)
Lat 95.00th-qrtle-8 63.00 ( 0.00%) 63.00 ( 0.00%)
Lat 99.00th-qrtle-8 71.00 ( 0.00%) 69.00 ( 2.82%)
Lat 99.50th-qrtle-8 74.00 ( 0.00%) 73.00 ( 1.35%)
Lat 99.90th-qrtle-8 98.00 ( 0.00%) 90.00 ( 8.16%)
Lat 50.00th-qrtle-16 56.00 ( 0.00%) 55.00 ( 1.79%)
Lat 75.00th-qrtle-16 68.00 ( 0.00%) 67.00 ( 1.47%)
Lat 90.00th-qrtle-16 77.00 ( 0.00%) 78.00 ( -1.30%)
Lat 95.00th-qrtle-16 82.00 ( 0.00%) 84.00 ( -2.44%)
Lat 99.00th-qrtle-16 90.00 ( 0.00%) 93.00 ( -3.33%)
Lat 99.50th-qrtle-16 93.00 ( 0.00%) 97.00 ( -4.30%)
Lat 99.90th-qrtle-16 110.00 ( 0.00%) 110.00 ( 0.00%)
Lat 50.00th-qrtle-32 68.00 ( 0.00%) 62.00 ( 8.82%)
Lat 75.00th-qrtle-32 90.00 ( 0.00%) 83.00 ( 7.78%)
Lat 90.00th-qrtle-32 110.00 ( 0.00%) 100.00 ( 9.09%)
Lat 95.00th-qrtle-32 122.00 ( 0.00%) 111.00 ( 9.02%)
Lat 99.00th-qrtle-32 145.00 ( 0.00%) 133.00 ( 8.28%)
Lat 99.50th-qrtle-32 154.00 ( 0.00%) 143.00 ( 7.14%)
Lat 99.90th-qrtle-32 2316.00 ( 0.00%) 515.00 ( 77.76%)
Lat 50.00th-qrtle-35 69.00 ( 0.00%) 72.00 ( -4.35%)
Lat 75.00th-qrtle-35 92.00 ( 0.00%) 95.00 ( -3.26%)
Lat 90.00th-qrtle-35 111.00 ( 0.00%) 114.00 ( -2.70%)
Lat 95.00th-qrtle-35 122.00 ( 0.00%) 124.00 ( -1.64%)
Lat 99.00th-qrtle-35 142.00 ( 0.00%) 144.00 ( -1.41%)
Lat 99.50th-qrtle-35 150.00 ( 0.00%) 154.00 ( -2.67%)
Lat 99.90th-qrtle-35 6104.00 ( 0.00%) 5640.00 ( 7.60%)
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Giovanni Gherdovich <ggherdovich@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180213133730.24064-4-mgorman@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On sync wakeups, the previous CPU effective load may not be used so delay
the calculation until it's needed.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Giovanni Gherdovich <ggherdovich@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180213133730.24064-3-mgorman@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The only caller of wake_affine() knows the CPU ID. Pass it in instead of
rechecking it.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Giovanni Gherdovich <ggherdovich@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180213133730.24064-2-mgorman@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The default values for nreader and nwriter are apparently not all that
user-friendly, resulting in people doing scalability tests that ran all
runs at large scale. This commit therefore makes both the nreaders and
nwriters module default to the number of CPUs, and adds a comment to
rcuperf.c stating that the number of CPUs should be specified using the
nr_cpus kernel boot parameter. This commit also eliminates the redundant
rcuperf scripting specification of default values for these parameters.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The rcu_torture_writer() function adapts to requested testing from module
parameters as well as the function pointers in the structure referenced
by cur_ops. However, as long as the module parameters do not conflict
with the function pointers, this adaptation is silent. This silence can
result in confusion as to exactly what was tested, which could in turn
result in untested RCU code making its way into mainline.
This commit therefore makes rcu_torture_writer() announce exactly which
portions of RCU's API it ends up testing.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
During boot, normal grace periods are processed as expedited. When
rcutorture is built into the kernel, it starts during boot and thus
detects that normal grace periods are unconditionally expedited.
Therefore, rcutorture concludes that there is no point in trying
to dynamically enable expediting, do it disables this aspect of testing,
which is a bit of an overreaction to the temporary boot-time expediting.
This commit therefore rechecks forced expediting throughout the test,
enabling dynamic expediting if normal grace periods are processed
normally at any point.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently the rcu_torture_fakewriter() function invokes cur_ops->sync()
and cur_ops->exp_sync() without first checking to see if they are in
fact non-NULL. This results in kernel NULL pointer dereferences when
testing RCU implementations that choose not to provide the full set of
primitives. Given that it is perfectly reasonable to have specialized
RCU implementations that provide only a subset of the RCU API, this is
a bug in rcutorture.
This commit therefore makes rcu_torture_fakewriter() check function
pointers before invoking them, thus allowing it to test subsetted
RCU implementations.
Reported-by: Lihao Liang <lianglihao@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit moves to __func__ for function names and for KBUILD_MODNAME
for module names, all in the name of better resilience to change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit replaces array-allocation calls to kzalloc() with
equivalent calls to kcalloc().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The code in srcu_gp_end() inserts a delay every 0x3ff grace periods in
order to prevent SRCU grace-period work from consuming an entire CPU
when there is a long sequence of expedited SRCU grace-period requests.
However, all of SRCU's grace-period work is carried out in workqueues,
which are in turn within kthreads, which are automatically throttled as
needed by the scheduler. In particular, if there is plenty of idle time,
there is no point in throttling.
This commit therefore removes the expedited SRCU grace-period throttling.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Of course, compilers will optimize out a dead code. Anyway, remove
any dead code for better readibility.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Currently, given a multi-level srcu_node tree, SRCU can scan the full
set of srcu_data structures at each level when cleaning up after a grace
period. This, though harmless otherwise, represents pointless overhead.
This commit therefore eliminates this overhead by scanning the srcu_data
structures only when traversing the leaf srcu_node structures.
Signed-off-by: Ildar Ismagilov <devix84@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
SRCU checks each srcu_data structure's grace-period number for counter
wrap four times per cycle by default. This frequency guarantees that
normal comparisons will detect potential wrap. However, the expedited
grace-period number is not checked. The consquences are not too horrible
(a failure to expedite a grace period when requested), but it would be
good to avoid such things. This commit therefore adds this check to
the expedited grace-period number.
Signed-off-by: Ildar Ismagilov <devix84@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit moves to __func__ for function names in the name of better
resilience to change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit reworks the first loop in sync_rcu_exp_select_cpus()
to avoid doing unnecssary stores to other CPUs' rcu_data
structures. This speeds up that first loop by roughly a factor of
two on an old x86 system. In the case where the system is mostly
idle, this loop incurs a large fraction of the overhead of the
synchronize_rcu_expedited(). There is less benefit on busy systems
because the overhead of the smp_call_function_single() in the second
loop dominates in that case.
However, it is not unusual to do configuration chances involving
RCU grace periods (both expedited and normal) while the system is
mostly idle, so this optimization is worth doing.
While we are in the area, this commit also adds parentheses to arguments
used by the for_each_leaf_node_possible_cpu() macro.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
If a CPU is transitioning to or from offline state, an expedited
grace period may undergo a timed wait. This timed wait can unduly
delay grace periods, so this commit adds a trace statement to make
it visible.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
This commit adds more tracing of expedited grace periods to enable
improved debugging of slowdowns.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The srcu_funnel_exp_start() function checks to see if the srcu_struct
structure's expedited grace period counter needs updating to reflect a
newly arrived request for an expedited SRCU grace period. Unfortunately,
the check is backwards, so this commit reverses the sense of the test.
Signed-off-by: Ildar Ismagilov <devix84@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Commits c0b334c5bf and ea9b0c8a26 introduced new sparse warnings
by accessing rcu_node->lock directly and ignoring the __private
marker. Introduce a new wrapper and use it. Also fix a similar problem
in srcutree.c introduced by a3883df393.
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
RCU's nxttail has been optimized to be a rcu_segcblist, which is
a multi-tailed linked list with macros defined for the indexes for
each tail. The indexes have been defined in linux/rcu_segcblist.h,
so this commit removes the redundant definitions in kernel/rcu/tree.h.
Signed-off-by: Liu Changcheng <changcheng.liu@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The kernel/rcu/rcu.h file has a pair of consecutive #ifdefs on
CONFIG_TINY_RCU, so this commit consolidates them, thus saving a few
lines of code.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
It is not always obvious that the stack dump from a starved grace-period
kthread isn't instead that of a CPU stalling the current grace period.
This commit therefore adds a pr_err() flagging these dumps.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The debugfs interface displayed statistics on RCU-pending checks but
this interface has since been removed. This commit therefore removes the
no-longer-used rcu_state structure's ->n_force_qs_lh and ->n_force_qs_ngp
fields along with their updates. (Though the ->n_force_qs_ngp field
was actually not used at all, embarrassingly enough.)
If this information proves necessary in the future, the corresponding
event traces will be added.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The debugfs interface displayed statistics on RCU-pending checks
but this interface has since been removed. This commit therefore
removes the no-longer-used rcu_data structure's ->n_rcu_pending,
->n_rp_core_needs_qs, ->n_rp_report_qs, ->n_rp_cb_ready,
->n_rp_cpu_needs_gp, ->n_rp_gp_completed, ->n_rp_gp_started,
->n_rp_nocb_defer_wakeup, and ->n_rp_need_nothing fields along with
their updates.
If this information proves necessary in the future, the corresponding
event traces will be added.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The debugfs interface displayed statistics on RCU callback invocation but
this interface has since been removed. This commit therefore removes the
no-longer-used rcu_data structure's ->n_cbs_invoked and ->n_nocbs_invoked
fields along with their updates.
If this information proves necessary in the future, the corresponding
event traces will be added.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
The debugfs interface displayed statistics on RCU priority boosting,
but this interface has since been removed. This commit therefore
removes the no-longer-used rcu_data structure's ->n_tasks_boosted,
->n_exp_boosts, and ->n_exp_boosts and their updates.
If this information proves necessary in the future, the corresponding
event traces will be added.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
In CONFIG_RCU_NOCB_CPU=y kernels, if the boot parameters indicate that
none of the CPUs should in fact be offloaded, the following somewhat
obtuse message appears:
Offload RCU callbacks from CPUs: .
This commit therefore makes the message at least grammatically correct
in this case:
Offload RCU callbacks from CPUs: (none)
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Pull perf updates from Thomas Gleixner:
"Perf tool updates and kprobe fixes:
- perf_mmap overwrite mode fixes/overhaul, prep work to get 'perf
top' using it, making it bearable to use it in large core count
systems such as Knights Landing/Mill Intel systems (Kan Liang)
- s/390 now uses syscall.tbl, just like x86-64 to generate the
syscall table id -> string tables used by 'perf trace' (Hendrik
Brueckner)
- Use strtoull() instead of home grown function (Andy Shevchenko)
- Synchronize kernel ABI headers, v4.16-rc1 (Ingo Molnar)
- Document missing 'perf data --force' option (Sangwon Hong)
- Add perf vendor JSON metrics for ARM Cortex-A53 Processor (William
Cohen)
- Improve error handling and error propagation of ftrace based
kprobes so failures when installing kprobes are not silently
ignored and create disfunctional tracepoints"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
kprobes: Propagate error from disarm_kprobe_ftrace()
kprobes: Propagate error from arm_kprobe_ftrace()
Revert "tools include s390: Grab a copy of arch/s390/include/uapi/asm/unistd.h"
perf s390: Rework system call table creation by using syscall.tbl
perf s390: Grab a copy of arch/s390/kernel/syscall/syscall.tbl
tools/headers: Synchronize kernel ABI headers, v4.16-rc1
perf test: Fix test trace+probe_libc_inet_pton.sh for s390x
perf data: Document missing --force option
perf tools: Substitute yet another strtoull()
perf top: Check the latency of perf_top__mmap_read()
perf top: Switch default mode to overwrite mode
perf top: Remove lost events checking
perf hists browser: Add parameter to disable lost event warning
perf top: Add overwrite fall back
perf evsel: Expose the perf_missing_features struct
perf top: Check per-event overwrite term
perf mmap: Discard legacy interface for mmap read
perf test: Update mmap read functions for backward-ring-buffer test
perf mmap: Introduce perf_mmap__read_event()
perf mmap: Introduce perf_mmap__read_done()
...
Pull irq updates from Thomas Gleixner:
"A small set of updates mostly for irq chip drivers:
- MIPS GIC fix for spurious, masked interrupts
- fix for a subtle IPI bug in GICv3
- do not probe GICv3 ITSs that are marked as disabled
- multi-MSI support for GICv2m
- various small cleanups"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqdomain: Re-use DEFINE_SHOW_ATTRIBUTE() macro
irqchip/bcm: Remove hashed address printing
irqchip/gic-v2m: Add PCI Multi-MSI support
irqchip/gic-v3: Ignore disabled ITS nodes
irqchip/gic-v3: Use wmb() instead of smb_wmb() in gic_raise_softirq()
irqchip/gic-v3: Change pr_debug message to pr_devel
irqchip/mips-gic: Avoid spuriously handling masked interrupts
Introduce a helper to retrieve the current task's work struct if it is
a workqueue worker.
This allows us to fix a long-standing deadlock in several DRM drivers
wherein the ->runtime_suspend callback waits for a specific worker to
finish and that worker in turn calls a function which waits for runtime
suspend to finish. That function is invoked from multiple call sites
and waiting for runtime suspend to finish is the correct thing to do
except if it's executing in the context of the worker.
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/2d8f603074131eb87e588d2b803a71765bd3a2fd.1518338788.git.lukas@wunner.de
...instead of open coding file operations followed by custom ->open()
callbacks per each attribute.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Improve error handling when disarming ftrace-based kprobes. Like with
arm_kprobe_ftrace(), propagate any errors from disarm_kprobe_ftrace() so
that we do not disable/unregister kprobes that are still armed. In other
words, unregister_kprobe() and disable_kprobe() should not report success
if the kprobe could not be disarmed.
disarm_all_kprobes() keeps its current behavior and attempts to
disarm all kprobes. It returns the last encountered error and gives a
warning if not all probes could be disarmed.
This patch is based on Petr Mladek's original patchset (patches 2 and 3)
back in 2015, which improved kprobes error handling, found here:
https://lkml.org/lkml/2015/2/26/452
However, further work on this had been paused since then and the patches
were not upstreamed.
Based-on-patches-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20180109235124.30886-3-jeyu@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Improve error handling when arming ftrace-based kprobes. Specifically, if
we fail to arm a ftrace-based kprobe, register_kprobe()/enable_kprobe()
should report an error instead of success. Previously, this has lead to
confusing situations where register_kprobe() would return 0 indicating
success, but the kprobe would not be functional if ftrace registration
during the kprobe arming process had failed. We should therefore take any
errors returned by ftrace into account and propagate this error so that we
do not register/enable kprobes that cannot be armed. This can happen if,
for example, register_ftrace_function() finds an IPMODIFY conflict (since
kprobe_ftrace_ops has this flag set) and returns an error. Such a conflict
is possible since livepatches also set the IPMODIFY flag for their ftrace_ops.
arm_all_kprobes() keeps its current behavior and attempts to arm all
kprobes. It returns the last encountered error and gives a warning if
not all probes could be armed.
This patch is based on Petr Mladek's original patchset (patches 2 and 3)
back in 2015, which improved kprobes error handling, found here:
https://lkml.org/lkml/2015/2/26/452
However, further work on this had been paused since then and the patches
were not upstreamed.
Based-on-patches-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20180109235124.30886-2-jeyu@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
syzkaller recently triggered OOM during percpu map allocation;
while there is work in progress by Dennis Zhou to add __GFP_NORETRY
semantics for percpu allocator under pressure, there seems also a
missing bpf_map_precharge_memlock() check in array map allocation.
Given today the actual bpf_map_charge_memlock() happens after the
find_and_alloc_map() in syscall path, the bpf_map_precharge_memlock()
is there to bail out early before we go and do the map setup work
when we find that we hit the limits anyway. Therefore add this for
array map as well.
Fixes: 6c90598174 ("bpf: pre-allocate hash map elements")
Fixes: a10423b87a ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map")
Reported-by: syzbot+adb03f3f0bb57ce3acda@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Dennis Zhou <dennisszhou@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit 6f1982fedd ("sched/isolation: Handle the nohz_full= parameter")
broke CONFIG_NO_HZ_FULL_ALL=y kernels. This breakage is due to the code
under CONFIG_NO_HZ_FULL_ALL failing to invoke the shiny new housekeeping
functions. This means that rcutorture scenario TREE04 now emits RCU CPU
stall warnings due to the RCU grace-period kthreads not being awakened
at a time of their choosing, or perhaps even not at all:
[ 27.731422] rcu_bh kthread starved for 21001 jiffies! g18446744073709551369 c18446744073709551368 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=3
[ 27.731423] rcu_bh I14936 9 2 0x80080000
[ 27.731435] Call Trace:
[ 27.731440] __schedule+0x31a/0x6d0
[ 27.731442] schedule+0x31/0x80
[ 27.731446] schedule_timeout+0x15a/0x320
[ 27.731453] ? call_timer_fn+0x130/0x130
[ 27.731457] rcu_gp_kthread+0x66c/0xea0
[ 27.731458] ? rcu_gp_kthread+0x66c/0xea0
Because no one has complained about CONFIG_NO_HZ_FULL_ALL=y being broken,
I hypothesize that no one is in fact using it, other than rcutorture.
This commit therefore eliminates CONFIG_NO_HZ_FULL_ALL and updates
rcutorture's config files to instead use the nohz_full= kernel parameter
to put the desired CPUs into nohz_full mode.
Fixes: 6f1982fedd ("sched/isolation: Handle the nohz_full= parameter")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Since rcu_boot_init_percpu_data() is only called at boot time,
there is no data race and spinlock is not needed.
Signed-off-by: Lihao Liang <lianglihao@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Pull locking fixes from Ingo Molnar:
"This contains two qspinlock fixes and three documentation and comment
fixes"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/semaphore: Update the file path in documentation
locking/atomic/bitops: Document and clarify ordering semantics for failed test_and_{}_bit()
locking/qspinlock: Ensure node->count is updated before initialising node
locking/qspinlock: Ensure node is initialised before updating prev->next
Documentation/locking/mutex-design: Update to reflect latest changes
This array appears to be completely unused, remove it.
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
syzkaller tried to perform a prog query in perf_event_query_prog_array()
where struct perf_event_query_bpf had an ids_len of 1,073,741,353 and
thus causing a warning due to failed kcalloc() allocation out of the
bpf_prog_array_copy_to_user() helper. Given we cannot attach more than
64 programs to a perf event, there's no point in allowing huge ids_len.
Therefore, allow a buffer that would fix the maximum number of ids and
also add a __GFP_NOWARN to the temporary ids buffer.
Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Fixes: 0911287ce3 ("bpf: fix bpf_prog_array_copy_to_user() issues")
Reported-by: syzbot+cab5816b0edbabf598b3@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There're several implications after commit 0bf7800f17 ("ptr_ring:
try vmalloc() when kmalloc() fails") with the using of vmalloc() since
can't allow GFP_ATOMIC but mandate GFP_KERNEL. This will lead a WARN
since cpumap try to call with GFP_ATOMIC. Fortunately, entry
allocation of cpumap can only be done through syscall path which means
GFP_ATOMIC is not necessary, so fixing this by replacing GFP_ATOMIC
with GFP_KERNEL.
Reported-by: syzbot+1a240cdb1f4cc88819df@syzkaller.appspotmail.com
Fixes: 0bf7800f17 ("ptr_ring: try vmalloc() when kmalloc() fails")
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: akpm@linux-foundation.org
Cc: dhowells@redhat.com
Cc: hannes@cmpxchg.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
In case user program provides silly parameters, we want
a map_alloc() handler to return an error, not a NULL pointer,
otherwise we crash later in find_and_alloc_map()
Fixes: 1aa12bdf1b ("bpf: sockmap, add sock close() hook to remove socks")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There is a memory leak happening in lpm_trie map_free callback
function trie_free. The trie structure itself does not get freed.
Also, trie_free function did not do synchronize_rcu before freeing
various data structures. This is incorrect as some rcu_read_lock
region(s) for lookup, update, delete or get_next_key may not complete yet.
The fix is to add synchronize_rcu in the beginning of trie_free.
The useless spin_lock is removed from this function as well.
Fixes: b95a5c4db0 ("bpf: add a longest prefix match trie map implementation")
Reported-by: Mathieu Malaterre <malat@debian.org>
Reported-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch starts to convert pernet_subsys, registered
from postcore initcalls.
audit_net_init() creates netlink socket, while audit_net_exit()
destroys it. The rest of the pernet_list are not interested
in the socket, so we make audit_net_ops async.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When queuing on the qspinlock, the count field for the current CPU's head
node is incremented. This needn't be atomic because locking in e.g. IRQ
context is balanced and so an IRQ will return with node->count as it
found it.
However, the compiler could in theory reorder the initialisation of
node[idx] before the increment of the head node->count, causing an
IRQ to overwrite the initialised node and potentially corrupt the lock
state.
Avoid the potential for this harmful compiler reordering by placing a
barrier() between the increment of the head node->count and the subsequent
node initialisation.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1518528177-19169-3-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
