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2018-07-25sched/numa: Evaluate move once per nodeSrikar Dronamraju
task_numa_compare() helps choose the best CPU to move or swap the selected task. To achieve this task_numa_compare() is called for every CPU in the node. Currently it evaluates if the task can be moved/swapped for each of the CPUs. However the move evaluation is mostly independent of the CPU. Evaluating the move logic once per node, provides scope for simplifying task_numa_compare(). Running SPECjbb2005 on a 4 node machine and comparing bops/JVM JVMS LAST_PATCH WITH_PATCH %CHANGE 16 25705.2 25058.2 -2.51 1 74433 72950 -1.99 Running SPECjbb2005 on a 16 node machine and comparing bops/JVM JVMS LAST_PATCH WITH_PATCH %CHANGE 8 96589.6 105930 9.670 1 181830 178624 -1.76 (numbers from v1 based on v4.17-rc5) Testcase Time: Min Max Avg StdDev numa01.sh Real: 440.65 941.32 758.98 189.17 numa01.sh Sys: 183.48 320.07 258.42 50.09 numa01.sh User: 37384.65 71818.14 60302.51 13798.96 numa02.sh Real: 61.24 65.35 62.49 1.49 numa02.sh Sys: 16.83 24.18 21.40 2.60 numa02.sh User: 5219.59 5356.34 5264.03 49.07 numa03.sh Real: 822.04 912.40 873.55 37.35 numa03.sh Sys: 118.80 140.94 132.90 7.60 numa03.sh User: 62485.19 70025.01 67208.33 2967.10 numa04.sh Real: 690.66 872.12 778.49 65.44 numa04.sh Sys: 459.26 563.03 494.03 42.39 numa04.sh User: 51116.44 70527.20 58849.44 8461.28 numa05.sh Real: 418.37 562.28 525.77 54.27 numa05.sh Sys: 299.45 481.00 392.49 64.27 numa05.sh User: 34115.09 41324.02 39105.30 2627.68 Testcase Time: Min Max Avg StdDev %Change numa01.sh Real: 516.14 892.41 739.84 151.32 2.587% numa01.sh Sys: 153.16 192.99 177.70 14.58 45.42% numa01.sh User: 39821.04 69528.92 57193.87 10989.48 5.435% numa02.sh Real: 60.91 62.35 61.58 0.63 1.477% numa02.sh Sys: 16.47 26.16 21.20 3.85 0.943% numa02.sh User: 5227.58 5309.61 5265.17 31.04 -0.02% numa03.sh Real: 739.07 917.73 795.75 64.45 9.776% numa03.sh Sys: 94.46 136.08 109.48 14.58 21.39% numa03.sh User: 57478.56 72014.09 61764.48 5343.69 8.813% numa04.sh Real: 442.61 715.43 530.31 96.12 46.79% numa04.sh Sys: 224.90 348.63 285.61 48.83 72.97% numa04.sh User: 35836.84 47522.47 40235.41 3985.26 46.26% numa05.sh Real: 386.13 489.17 434.94 43.59 20.88% numa05.sh Sys: 144.29 438.56 278.80 105.78 40.77% numa05.sh User: 33255.86 36890.82 34879.31 1641.98 12.11% Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1529514181-9842-3-git-send-email-srikar@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25sched/debug: Show the sum wait time of a task groupYun Wang
Although we can rely on cpuacct to present the CPU usage of task groups, it is hard to tell how intense the competition is between these groups on CPU resources. Monitoring the wait time or sched_debug of each process could be very expensive, and there is no good way to accurately represent the conflict with these info, we need the wait time on group dimension. Thus we introduce group's wait_sum to represent the resource conflict between task groups, which is simply the sum of the wait time of the group's cfs_rq. The 'cpu.stat' is modified to show the statistic, like: nr_periods 0 nr_throttled 0 throttled_time 0 wait_sum 2035098795584 Now we can monitor the changes of wait_sum to tell how much a a task group is suffering in the fight of CPU resources. For example: (wait_sum - last_wait_sum) * 100 / (nr_cpu * period_ns) == X% means the task group paid X percentage of period on waiting for the CPU. Signed-off-by: Michael Wang <yun.wang@linux.alibaba.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/ff7dae3b-e5f9-7157-1caa-ff02c6b23dc1@linux.alibaba.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25sched/fair: Remove #ifdefs from scale_rt_capacity()Vincent Guittot
Reuse cpu_util_irq() that has been defined for schedutil and set irq util to 0 when !CONFIG_IRQ_TIME_ACCOUNTING. But the compiler is not able to optimize the sequence (at least with aarch64 GCC 7.2.1): free *= (max - irq); free /= max; when irq is fixed to 0 Add a new inline function scale_irq_capacity() that will scale utilization when irq is accounted. Reuse this funciton in schedutil which applies similar formula. Suggested-by: Ingo Molnar <mingo@redhat.com> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: rjw@rjwysocki.net Link: http://lkml.kernel.org/r/1532001606-6689-1-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25Merge branch 'sched/urgent' into sched/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25sched/rt: Restore rt_runtime after disabling RT_RUNTIME_SHAREHailong Liu
NO_RT_RUNTIME_SHARE feature is used to prevent a CPU borrow enough runtime with a spin-rt-task. However, if RT_RUNTIME_SHARE feature is enabled and rt_rq has borrowd enough rt_runtime at the beginning, rt_runtime can't be restored to its initial bandwidth rt_runtime after we disable RT_RUNTIME_SHARE. E.g. on my PC with 4 cores, procedure to reproduce: 1) Make sure RT_RUNTIME_SHARE is enabled cat /sys/kernel/debug/sched_features GENTLE_FAIR_SLEEPERS START_DEBIT NO_NEXT_BUDDY LAST_BUDDY CACHE_HOT_BUDDY WAKEUP_PREEMPTION NO_HRTICK NO_DOUBLE_TICK LB_BIAS NONTASK_CAPACITY TTWU_QUEUE NO_SIS_AVG_CPU SIS_PROP NO_WARN_DOUBLE_CLOCK RT_PUSH_IPI RT_RUNTIME_SHARE NO_LB_MIN ATTACH_AGE_LOAD WA_IDLE WA_WEIGHT WA_BIAS 2) Start a spin-rt-task ./loop_rr & 3) set affinity to the last cpu taskset -p 8 $pid_of_loop_rr 4) Observe that last cpu have borrowed enough runtime. cat /proc/sched_debug | grep rt_runtime .rt_runtime : 950.000000 .rt_runtime : 900.000000 .rt_runtime : 950.000000 .rt_runtime : 1000.000000 5) Disable RT_RUNTIME_SHARE echo NO_RT_RUNTIME_SHARE > /sys/kernel/debug/sched_features 6) Observe that rt_runtime can not been restored cat /proc/sched_debug | grep rt_runtime .rt_runtime : 950.000000 .rt_runtime : 900.000000 .rt_runtime : 950.000000 .rt_runtime : 1000.000000 This patch help to restore rt_runtime after we disable RT_RUNTIME_SHARE. Signed-off-by: Hailong Liu <liu.hailong6@zte.com.cn> Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn> 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: zhong.weidong@zte.com.cn Link: http://lkml.kernel.org/r/1531874815-39357-1-git-send-email-liu.hailong6@zte.com.cn Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25sched/deadline: Update rq_clock of later_rq when pushing a taskDaniel Bristot de Oliveira
Daniel Casini got this warn while running a DL task here at RetisLab: [ 461.137582] ------------[ cut here ]------------ [ 461.137583] rq->clock_update_flags < RQCF_ACT_SKIP [ 461.137599] WARNING: CPU: 4 PID: 2354 at kernel/sched/sched.h:967 assert_clock_updated.isra.32.part.33+0x17/0x20 [a ton of modules] [ 461.137646] CPU: 4 PID: 2354 Comm: label_image Not tainted 4.18.0-rc4+ #3 [ 461.137647] Hardware name: ASUS All Series/Z87-K, BIOS 0801 09/02/2013 [ 461.137649] RIP: 0010:assert_clock_updated.isra.32.part.33+0x17/0x20 [ 461.137649] Code: ff 48 89 83 08 09 00 00 eb c6 66 0f 1f 84 00 00 00 00 00 55 48 c7 c7 98 7a 6c a5 c6 05 bc 0d 54 01 01 48 89 e5 e8 a9 84 fb ff <0f> 0b 5d c3 0f 1f 44 00 00 0f 1f 44 00 00 83 7e 60 01 74 0a 48 3b [ 461.137673] RSP: 0018:ffffa77e08cafc68 EFLAGS: 00010082 [ 461.137674] RAX: 0000000000000000 RBX: ffff8b3fc1702d80 RCX: 0000000000000006 [ 461.137674] RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff8b3fded164b0 [ 461.137675] RBP: ffffa77e08cafc68 R08: 0000000000000026 R09: 0000000000000339 [ 461.137676] R10: ffff8b3fd060d410 R11: 0000000000000026 R12: ffffffffa4e14e20 [ 461.137677] R13: ffff8b3fdec22940 R14: ffff8b3fc1702da0 R15: ffff8b3fdec22940 [ 461.137678] FS: 00007efe43ee5700(0000) GS:ffff8b3fded00000(0000) knlGS:0000000000000000 [ 461.137679] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 461.137680] CR2: 00007efe30000010 CR3: 0000000301744003 CR4: 00000000001606e0 [ 461.137680] Call Trace: [ 461.137684] push_dl_task.part.46+0x3bc/0x460 [ 461.137686] task_woken_dl+0x60/0x80 [ 461.137689] ttwu_do_wakeup+0x4f/0x150 [ 461.137690] ttwu_do_activate+0x77/0x80 [ 461.137692] try_to_wake_up+0x1d6/0x4c0 [ 461.137693] wake_up_q+0x32/0x70 [ 461.137696] do_futex+0x7e7/0xb50 [ 461.137698] __x64_sys_futex+0x8b/0x180 [ 461.137701] do_syscall_64+0x5a/0x110 [ 461.137703] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 461.137705] RIP: 0033:0x7efe4918ca26 [ 461.137705] Code: 00 00 00 74 17 49 8b 48 20 44 8b 59 10 41 83 e3 30 41 83 fb 20 74 1e be 85 00 00 00 41 ba 01 00 00 00 41 b9 01 00 00 04 0f 05 <48> 3d 01 f0 ff ff 73 1f 31 c0 c3 be 8c 00 00 00 49 89 c8 4d 31 d2 [ 461.137738] RSP: 002b:00007efe43ee4928 EFLAGS: 00000283 ORIG_RAX: 00000000000000ca [ 461.137739] RAX: ffffffffffffffda RBX: 0000000005094df0 RCX: 00007efe4918ca26 [ 461.137740] RDX: 0000000000000001 RSI: 0000000000000085 RDI: 0000000005094e24 [ 461.137741] RBP: 00007efe43ee49c0 R08: 0000000005094e20 R09: 0000000004000001 [ 461.137741] R10: 0000000000000001 R11: 0000000000000283 R12: 0000000000000000 [ 461.137742] R13: 0000000005094df8 R14: 0000000000000001 R15: 0000000000448a10 [ 461.137743] ---[ end trace 187df4cad2bf7649 ]--- This warning happened in the push_dl_task(), because __add_running_bw()->cpufreq_update_util() is getting the rq_clock of the later_rq before its update, which takes place at activate_task(). The fix then is to update the rq_clock before calling add_running_bw(). To avoid double rq_clock_update() call, we set ENQUEUE_NOCLOCK flag to activate_task(). Reported-by: Daniel Casini <daniel.casini@santannapisa.it> Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Juri Lelli <juri.lelli@redhat.com> Cc: Clark Williams <williams@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luca Abeni <luca.abeni@santannapisa.it> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tommaso Cucinotta <tommaso.cucinotta@santannapisa.it> Fixes: e0367b12674b sched/deadline: Move CPU frequency selection triggering points Link: http://lkml.kernel.org/r/ca31d073a4788acf0684a8b255f14fea775ccf20.1532077269.git.bristot@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25stop_machine: Disable preemption after queueing stopper threadsIsaac J. Manjarres
This commit: 9fb8d5dc4b64 ("stop_machine, Disable preemption when waking two stopper threads") does not fully address the race condition that can occur as follows: On one CPU, call it CPU 3, thread 1 invokes cpu_stop_queue_two_works(2, 3,...), and the execution is such that thread 1 queues the works for migration/2 and migration/3, and is preempted after releasing the locks for migration/2 and migration/3, but before waking the threads. Then, On CPU 2, a kworker, call it thread 2, is running, and it invokes cpu_stop_queue_two_works(1, 2,...), such that thread 2 queues the works for migration/1 and migration/2. Meanwhile, on CPU 3, thread 1 resumes execution, and wakes migration/2 and migration/3. This means that when CPU 2 releases the locks for migration/1 and migration/2, but before it wakes those threads, it can be preempted by migration/2. If thread 2 is preempted by migration/2, then migration/2 will execute the first work item successfully, since migration/3 was woken up by CPU 3, but when it goes to execute the second work item, it disables preemption, calls multi_cpu_stop(), and thus, CPU 2 will wait forever for migration/1, which should have been woken up by thread 2. However migration/1 cannot be woken up by thread 2, since it is a kworker, so it is affine to CPU 2, but CPU 2 is running migration/2 with preemption disabled, so thread 2 will never run. Disable preemption after queueing works for stopper threads to ensure that the operation of queueing the works and waking the stopper threads is atomic. Co-Developed-by: Prasad Sodagudi <psodagud@codeaurora.org> Co-Developed-by: Pavankumar Kondeti <pkondeti@codeaurora.org> Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org> Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org> Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.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: bigeasy@linutronix.de Cc: gregkh@linuxfoundation.org Cc: matt@codeblueprint.co.uk Fixes: 9fb8d5dc4b64 ("stop_machine, Disable preemption when waking two stopper threads") Link: http://lkml.kernel.org/r/1531856129-9871-1-git-send-email-isaacm@codeaurora.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25sched/topology: Check variable group before dereferencing itYi Wang
The 'group' variable in sched_domain_debug_one() is not checked when firstly used in cpumask_test_cpu(cpu, sched_group_span(group)), but it might be NULL (it is checked later in the following while loop) and may cause NULL pointer dereference. We need to check it before using to avoid NULL dereference. Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: zhong.weidong@zte.com.cn Link: http://lkml.kernel.org/r/1532319547-33335-1-git-send-email-wang.yi59@zte.com.cn Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25locking/rtmutex: Allow specifying a subclass for nested lockingPeter Rosin
Needed for annotating rt_mutex locks. Tested-by: John Sperbeck <jsperbeck@google.com> Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Deepa Dinamani <deepadinamani@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Chang <dpf@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: Wolfram Sang <wsa@the-dreams.de> Link: http://lkml.kernel.org/r/20180720083914.1950-2-peda@axentia.se Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Handle stations tied to AP_VLANs properly during mac80211 hw reconfig. From Manikanta Pubbisetty. 2) Fix jump stack depth validation in nf_tables, from Taehee Yoo. 3) Fix quota handling in aRFS flow expiration of mlx5 driver, from Eran Ben Elisha. 4) Exit path handling fix in powerpc64 BPF JIT, from Daniel Borkmann. 5) Use ptr_ring_consume_bh() in page pool code, from Tariq Toukan. 6) Fix cached netdev name leak in nf_tables, from Florian Westphal. 7) Fix memory leaks on chain rename, also from Florian Westphal. 8) Several fixes to DCTCP congestion control ACK handling, from Yuchunk Cheng. 9) Missing rcu_read_unlock() in CAIF protocol code, from Yue Haibing. 10) Fix link local address handling with VRF, from David Ahern. 11) Don't clobber 'err' on a successful call to __skb_linearize() in skb_segment(). From Eric Dumazet. 12) Fix vxlan fdb notification races, from Roopa Prabhu. 13) Hash UDP fragments consistently, from Paolo Abeni. 14) If TCP receives lots of out of order tiny packets, we do really silly stuff. Make the out-of-order queue ending more robust to this kind of behavior, from Eric Dumazet. 15) Don't leak netlink dump state in nf_tables, from Florian Westphal. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits) net: axienet: Fix double deregister of mdio qmi_wwan: fix interface number for DW5821e production firmware ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull bnx2x: Fix invalid memory access in rss hash config path. net/mlx4_core: Save the qpn from the input modifier in RST2INIT wrapper r8169: restore previous behavior to accept BIOS WoL settings cfg80211: never ignore user regulatory hint sock: fix sg page frag coalescing in sk_alloc_sg netfilter: nf_tables: move dumper state allocation into ->start tcp: add tcp_ooo_try_coalesce() helper tcp: call tcp_drop() from tcp_data_queue_ofo() tcp: detect malicious patterns in tcp_collapse_ofo_queue() tcp: avoid collapses in tcp_prune_queue() if possible tcp: free batches of packets in tcp_prune_ofo_queue() ip: hash fragments consistently ipv6: use fib6_info_hold_safe() when necessary can: xilinx_can: fix power management handling can: xilinx_can: fix incorrect clear of non-processed interrupts can: xilinx_can: fix RX overflow interrupt not being enabled can: xilinx_can: keep only 1-2 frames in TX FIFO to fix TX accounting ...
2018-07-24bpf: btf: Ensure the member->offset is in the right orderMartin KaFai Lau
This patch ensures the member->offset of a struct is in the correct order (i.e the later member's offset cannot go backward). The current "pahole -J" BTF encoder does not generate something like this. However, checking this can ensure future encoder will not violate this. Fixes: 69b693f0aefa ("bpf: btf: Introduce BPF Type Format (BTF)") Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-21Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Two fixes: a stop-machine preemption fix and a SCHED_DEADLINE fix" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/deadline: Fix switched_from_dl() warning stop_machine: Disable preemption when waking two stopper threads
2018-07-21mm: make vm_area_alloc() initialize core fieldsLinus Torvalds
Like vm_area_dup(), it initializes the anon_vma_chain head, and the basic mm pointer. The rest of the fields end up being different for different users, although the plan is to also initialize the 'vm_ops' field to a dummy entry. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-21mm: make vm_area_dup() actually copy the old vma dataLinus Torvalds
.. and re-initialize th eanon_vma_chain head. This removes some boiler-plate from the users, and also makes it clear why it didn't need use the 'zalloc()' version. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-21mm: use helper functions for allocating and freeing vm_area structsLinus Torvalds
The vm_area_struct is one of the most fundamental memory management objects, but the management of it is entirely open-coded evertwhere, ranging from allocation and freeing (using kmem_cache_[z]alloc and kmem_cache_free) to initializing all the fields. We want to unify this in order to end up having some unified initialization of the vmas, and the first step to this is to at least have basic allocation functions. Right now those functions are literally just wrappers around the kmem_cache_*() calls. This is a purely mechanical conversion: # new vma: kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL) -> vm_area_alloc() # copy old vma kmem_cache_alloc(vm_area_cachep, GFP_KERNEL) -> vm_area_dup(old) # free vma kmem_cache_free(vm_area_cachep, vma) -> vm_area_free(vma) to the point where the old vma passed in to the vm_area_dup() function isn't even used yet (because I've left all the old manual initialization alone). Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-20bpf: btf: Clean up BTF_INT_BITS() in uapi btf.hMartin KaFai Lau
This patch shrinks the BTF_INT_BITS() mask. The current btf_int_check_meta() ensures the nr_bits of an integer cannot exceed 64. Hence, it is mostly an uapi cleanup. The actual btf usage (i.e. seq_show()) is also modified to use u8 instead of u16. The verification (e.g. btf_int_check_meta()) path stays as is to deal with invalid BTF situation. Fixes: 69b693f0aefa ("bpf: btf: Introduce BPF Type Format (BTF)") Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: "Lots of fixes, here goes: 1) NULL deref in qtnfmac, from Gustavo A. R. Silva. 2) Kernel oops when fw download fails in rtlwifi, from Ping-Ke Shih. 3) Lost completion messages in AF_XDP, from Magnus Karlsson. 4) Correct bogus self-assignment in rhashtable, from Rishabh Bhatnagar. 5) Fix regression in ipv6 route append handling, from David Ahern. 6) Fix masking in __set_phy_supported(), from Heiner Kallweit. 7) Missing module owner set in x_tables icmp, from Florian Westphal. 8) liquidio's timeouts are HZ dependent, fix from Nicholas Mc Guire. 9) Link setting fixes for sh_eth and ravb, from Vladimir Zapolskiy. 10) Fix NULL deref when using chains in act_csum, from Davide Caratti. 11) XDP_REDIRECT needs to check if the interface is up and whether the MTU is sufficient. From Toshiaki Makita. 12) Net diag can do a double free when killing TCP_NEW_SYN_RECV connections, from Lorenzo Colitti. 13) nf_defrag in ipv6 can unnecessarily hold onto dst entries for a full minute, delaying device unregister. From Eric Dumazet. 14) Update MAC entries in the correct order in ixgbe, from Alexander Duyck. 15) Don't leave partial mangles bpf program in jit_subprogs, from Daniel Borkmann. 16) Fix pfmemalloc SKB state propagation, from Stefano Brivio. 17) Fix ACK handling in DCTCP congestion control, from Yuchung Cheng. 18) Use after free in tun XDP_TX, from Toshiaki Makita. 19) Stale ipv6 header pointer in ipv6 gre code, from Prashant Bhole. 20) Don't reuse remainder of RX page when XDP is set in mlx4, from Saeed Mahameed. 21) Fix window probe handling of TCP rapair sockets, from Stefan Baranoff. 22) Missing socket locking in smc_ioctl(), from Ursula Braun. 23) IPV6_ILA needs DST_CACHE, from Arnd Bergmann. 24) Spectre v1 fix in cxgb3, from Gustavo A. R. Silva. 25) Two spots in ipv6 do a rol32() on a hash value but ignore the result. Fixes from Colin Ian King" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (176 commits) tcp: identify cryptic messages as TCP seq # bugs ptp: fix missing break in switch hv_netvsc: Fix napi reschedule while receive completion is busy MAINTAINERS: Drop inactive Vitaly Bordug's email net: cavium: Add fine-granular dependencies on PCI net: qca_spi: Fix log level if probe fails net: qca_spi: Make sure the QCA7000 reset is triggered net: qca_spi: Avoid packet drop during initial sync ipv6: fix useless rol32 call on hash ipv6: sr: fix useless rol32 call on hash net: sched: Using NULL instead of plain integer net: usb: asix: replace mii_nway_restart in resume path net: cxgb3_main: fix potential Spectre v1 lib/rhashtable: consider param->min_size when setting initial table size net/smc: reset recv timeout after clc handshake net/smc: add error handling for get_user() net/smc: optimize consumer cursor updates net/nfc: Avoid stalls when nfc_alloc_send_skb() returned NULL. ipv6: ila: select CONFIG_DST_CACHE net: usb: rtl8150: demote allmulti message to dev_dbg() ...
2018-07-17Mark HI and TASKLET softirq synchronousLinus Torvalds
Way back in 4.9, we committed 4cd13c21b207 ("softirq: Let ksoftirqd do its job"), and ever since we've had small nagging issues with it. For example, we've had: 1ff688209e2e ("watchdog: core: make sure the watchdog_worker is not deferred") 8d5755b3f77b ("watchdog: softdog: fire watchdog even if softirqs do not get to run") 217f69743681 ("net: busy-poll: allow preemption in sk_busy_loop()") all of which worked around some of the effects of that commit. The DVB people have also complained that the commit causes excessive USB URB latencies, which seems to be due to the USB code using tasklets to schedule USB traffic. This seems to be an issue mainly when already living on the edge, but waiting for ksoftirqd to handle it really does seem to cause excessive latencies. Now Hanna Hawa reports that this issue isn't just limited to USB URB and DVB, but also causes timeout problems for the Marvell SoC team: "I'm facing kernel panic issue while running raid 5 on sata disks connected to Macchiatobin (Marvell community board with Armada-8040 SoC with 4 ARMv8 cores of CA72) Raid 5 built with Marvell DMA engine and async_tx mechanism (ASYNC_TX_DMA [=y]); the DMA driver (mv_xor_v2) uses a tasklet to clean the done descriptors from the queue" The latency problem causes a panic: mv_xor_v2 f0400000.xor: dma_sync_wait: timeout! Kernel panic - not syncing: async_tx_quiesce: DMA error waiting for transaction We've discussed simply just reverting the original commit entirely, and also much more involved solutions (with per-softirq threads etc). This patch is intentionally stupid and fairly limited, because the issue still remains, and the other solutions either got sidetracked or had other issues. We should probably also consider the timer softirqs to be synchronous and not be delayed to ksoftirqd (since they were the issue with the earlier watchdog problems), but that should be done as a separate patch. This does only the tasklet cases. Reported-and-tested-by: Hanna Hawa <hannah@marvell.com> Reported-and-tested-by: Josef Griebichler <griebichler.josef@gmx.at> Reported-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-17genirq: Remove redundant NULL pointer check in __free_irq()RAGHU Halharvi
The NULL pointer check in __free_irq() triggers a 'dereference before NULL pointer check' warning in static code analysis. It turns out that the check is redundant because all callers have a NULL pointer check already. Remove it. Signed-off-by: RAGHU Halharvi <raghuhack78@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20180717102009.7708-1-raghuhack78@gmail.com
2018-07-17Merge branch 'for-mingo' of ↵Ingo Molnar
git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu Pull RCU updates from Paul E. McKenney: - An optimization and a fix for RCU expedited grace periods, with the fix being from Boqun Feng. - Miscellaneous fixes, including a lockdep-annotation fix from Boqun Feng. - SRCU updates. - Updates to rcutorture and associated scripting. - Introduce grace-period sequence numbers to the RCU-bh, RCU-preempt, and RCU-sched flavors, replacing the old ->gpnum and ->completed pair of fields. This change allows lockless code to obtain the complete grace-period state with a single READ_ONCE(), which is needed to maintain tolerable lock contention during the upcoming consolidation of the three RCU flavors. Note that grace-period sequence numbers are already used by rcu_barrier(), expedited RCU grace periods, and SRCU, and are thus already heavily used and well-tested. Joel Fernandes contributed a number of excellent fixes and improvements. - Clean up some grace-period-reporting loose ends, including improving the handling of quiescent states from offline CPUs and fixing some false-positive WARN_ON_ONCE() invocations. (Strictly speaking, the WARN_ON_ONCE() invocations were quite correct, but their invariants were (harmlessly) violated by the earlier sloppy handling of quiescent states from offline CPUs.) In addition, improve grace-period forward-progress guarantees so as to allow removal of fail-safe checks that required otherwise needless lock acquisitions. Finally, add more diagnostics to help debug the upcoming consolidation of the RCU-bh, RCU-preempt, and RCU-sched flavors. - Additional miscellaneous fixes, including those contributed by Byungchul Park, Mauro Carvalho Chehab, Joe Perches, Joel Fernandes, Steven Rostedt, Andrea Parri, and Neil Brown. - Additional torture-test changes, including several contributed by Arnd Bergmann and Joel Fernandes. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16sched/core: Remove get_cpu() from sched_fork()Sebastian Andrzej Siewior
get_cpu() disables preemption for the entire sched_fork() function. This get_cpu() was introduced in commit: dd41f596cda0 ("sched: cfs core code") ... which also invoked sched_balance_self() and this function required preemption do be off. Today, sched_balance_self() seems to be moved to ->task_fork callback which is invoked while the ->pi_lock is held. set_load_weight() could invoke reweight_task() which then via $callchain might end up in smp_processor_id() but since `update_load' is false this won't happen. I didn't find any this_cpu*() or similar usage during the initialisation of the task_struct. The `cpu' value (from get_cpu()) is only used later in __set_task_cpu() while the ->pi_lock lock is held. Based on this it is possible to remove get_cpu() and use smp_processor_id() for the `cpu' variable without breaking anything. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> 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/20180706130615.g2ex2kmfu5kcvlq6@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16sched/cpufreq: Clarify sugov_get_util()Peter Zijlstra
Add a few comments to (hopefully) clarifying some of the magic in sugov_get_util(). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Link: http://lkml.kernel.org/r/20180705123617.GM2458@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16sched/sysctl: Remove unused sched_time_avg_ms sysctlVincent Guittot
/proc/sys/kernel/sched_time_avg_ms entry is not used anywhere, remove it. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1530200714-4504-12-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16sched/core: Remove the rt_avg codeVincent Guittot
rt_avg is not used anywhere anymore, so we can remove all related code. 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: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1530200714-4504-11-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16sched/core: Use PELT for scale_rt_capacity()Vincent Guittot
The utilization of the CPU by RT, DL and IRQs are now tracked with PELT so we can use these metrics instead of rt_avg to evaluate the remaining capacity available for CFS class. scale_rt_capacity() behavior has been changed and now returns the remaining capacity available for CFS instead of a scaling factor because RT, DL and IRQ provide now absolute utilization value. The same formula as schedutil is used: IRQ util_avg + (1 - IRQ util_avg / max capacity ) * /Sum rq util_avg but the implementation is different because it doesn't return the same value and doesn't benefit of the same optimization. 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: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1530200714-4504-10-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15sched/cpufreq: Remove sugov_aggregate_util()Vincent Guittot
There is no reason why sugov_get_util() and sugov_aggregate_util() were in fact separate functions. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> [ Rebased after adding irq tracking and fixed some compilation errors. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Link: http://lkml.kernel.org/r/1530200714-4504-9-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15cpufreq/schedutil: Take time spent in interrupts into accountVincent Guittot
The time spent executing IRQ handlers can be significant but it is not reflected in the utilization of CPU when deciding to choose an OPP. Now that we have access to this metric, schedutil can take it into account when selecting the OPP for a CPU. RQS utilization don't see the time spend under interrupt context and report their value in the normal context time window. We need to compensate this when adding interrupt utilization The CPU utilization is: IRQ util_avg + (1 - IRQ util_avg / max capacity ) * /Sum rq util_avg A test with iperf on hikey (octo arm64) gives the following speedup: iperf -c server_address -r -t 5 w/o patch w/ patch Tx 276 Mbits/sec 304 Mbits/sec +10% Rx 299 Mbits/sec 328 Mbits/sec +9% 8 iterations stdev is lower than 1% Only WFI idle state is enabled (shallowest idle state). Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Link: http://lkml.kernel.org/r/1530200714-4504-8-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15sched/irq: Add IRQ utilization trackingVincent Guittot
interrupt and steal time are the only remaining activities tracked by rt_avg. Like for sched classes, we can use PELT to track their average utilization of the CPU. But unlike sched class, we don't track when entering/leaving interrupt; Instead, we take into account the time spent under interrupt context when we update rqs' clock (rq_clock_task). This also means that we have to decay the normal context time and account for interrupt time during the update. That's also important to note that because: rq_clock == rq_clock_task + interrupt time and rq_clock_task is used by a sched class to compute its utilization, the util_avg of a sched class only reflects the utilization of the time spent in normal context and not of the whole time of the CPU. The utilization of interrupt gives an more accurate level of utilization of CPU. The CPU utilization is: avg_irq + (1 - avg_irq / max capacity) * /Sum avg_rq Most of the time, avg_irq is small and neglictible so the use of the approximation CPU utilization = /Sum avg_rq was enough. 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: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1530200714-4504-7-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15cpufreq/schedutil: Use DL utilization trackingVincent Guittot
Now that we have both the DL class bandwidth requirement and the DL class utilization, we can detect when CPU is fully used so we should run at max. Otherwise, we keep using the DL bandwidth requirement to define the utilization of the CPU. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Link: http://lkml.kernel.org/r/1530200714-4504-6-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15sched/dl: Add dl_rq utilization trackingVincent Guittot
Similarly to what happens with RT tasks, CFS tasks can be preempted by DL tasks and the CFS's utilization might no longer describes the real utilization level. Current DL bandwidth reflects the requirements to meet deadline when tasks are enqueued but not the current utilization of the DL sched class. We track DL class utilization to estimate the system utilization. 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: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1530200714-4504-5-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15cpufreq/schedutil: Use RT utilization trackingVincent Guittot
Add both CFS and RT utilization when selecting an OPP for CFS tasks as RT can preempt and steal CFS's running time. RT util_avg is used to take into account the utilization of RT tasks on the CPU when selecting OPP. If a RT task migrate, the RT utilization will not migrate but will decay over time. On an overloaded CPU, CFS utilization reflects the remaining utilization avialable on CPU. When RT task migrates, the CFS utilization will increase when tasks will start to use the newly available capacity. At the same pace, RT utilization will decay and both variations will compensate each other to keep unchanged overall utilization and will prevent any OPP drop. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Link: http://lkml.kernel.org/r/1530200714-4504-4-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15sched/rt: Add rt_rq utilization trackingVincent Guittot
schedutil governor relies on cfs_rq's util_avg to choose the OPP when CFS tasks are running. When the CPU is overloaded by CFS and RT tasks, CFS tasks are preempted by RT tasks and in this case util_avg reflects the remaining capacity but not what CFS want to use. In such case, schedutil can select a lower OPP whereas the CPU is overloaded. In order to have a more accurate view of the utilization of the CPU, we track the utilization of RT tasks. Only util_avg is correctly tracked but not load_avg and runnable_load_avg which are useless for rt_rq. rt_rq uses rq_clock_task and cfs_rq uses cfs_rq_clock_task but they are the same at the root group level, so the PELT windows of the util_sum are aligned. 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: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1530200714-4504-3-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15sched/pelt: Move PELT related code in a dedicated fileVincent Guittot
We want to track rt_rq's utilization as a part of the estimation of the whole rq's utilization. This is necessary because rt tasks can steal utilization to cfs tasks and make them lighter than they are. As we want to use the same load tracking mecanism for both and prevent useless dependency between cfs and rt code, PELT code is moved in a dedicated file. 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: Morten.Rasmussen@arm.com Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: daniel.lezcano@linaro.org Cc: dietmar.eggemann@arm.com Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: luca.abeni@santannapisa.it Cc: patrick.bellasi@arm.com Cc: quentin.perret@arm.com Cc: rjw@rjwysocki.net Cc: valentin.schneider@arm.com Cc: viresh.kumar@linaro.org Link: http://lkml.kernel.org/r/1530200714-4504-2-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15sched/fair: Fix util_avg of new tasks for asymmetric systemsQuentin Perret
When a new task wakes-up for the first time, its initial utilization is set to half of the spare capacity of its CPU. The current implementation of post_init_entity_util_avg() uses SCHED_CAPACITY_SCALE directly as a capacity reference. As a result, on a big.LITTLE system, a new task waking up on an idle little CPU will be given ~512 of util_avg, even if the CPU's capacity is significantly less than that. Fix this by computing the spare capacity with arch_scale_cpu_capacity(). Signed-off-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Vincent Guittot <vincent.guittot@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dietmar.eggemann@arm.com Cc: morten.rasmussen@arm.com Cc: patrick.bellasi@arm.com Link: http://lkml.kernel.org/r/20180612112215.25448-1-quentin.perret@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15watchdog/softlockup: Fix cpu_stop_queue_work() double-queue bugPeter Zijlstra
When scheduling is delayed for longer than the softlockup interrupt period it is possible to double-queue the cpu_stop_work, causing list corruption. Cure this by adding a completion to track the cpu_stop_work's progress. Reported-by: kernel test robot <lkp@intel.com> Tested-by: Rong Chen <rong.a.chen@intel.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> Fixes: 9cf57731b63e ("watchdog/softlockup: Replace "watchdog/%u" threads with cpu_stop_work") Link: http://lkml.kernel.org/r/20180713104208.GW2494@hirez.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15sched/deadline: Fix switched_from_dl() warningJuri Lelli
Mark noticed that syzkaller is able to reliably trigger the following warning: dl_rq->running_bw > dl_rq->this_bw WARNING: CPU: 1 PID: 153 at kernel/sched/deadline.c:124 switched_from_dl+0x454/0x608 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 153 Comm: syz-executor253 Not tainted 4.18.0-rc3+ #29 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x458 show_stack+0x20/0x30 dump_stack+0x180/0x250 panic+0x2dc/0x4ec __warn_printk+0x0/0x150 report_bug+0x228/0x2d8 bug_handler+0xa0/0x1a0 brk_handler+0x2f0/0x568 do_debug_exception+0x1bc/0x5d0 el1_dbg+0x18/0x78 switched_from_dl+0x454/0x608 __sched_setscheduler+0x8cc/0x2018 sys_sched_setattr+0x340/0x758 el0_svc_naked+0x30/0x34 syzkaller reproducer runs a bunch of threads that constantly switch between DEADLINE and NORMAL classes while interacting through futexes. The splat above is caused by the fact that if a DEADLINE task is setattr back to NORMAL while in non_contending state (blocked on a futex - inactive timer armed), its contribution to running_bw is not removed before sub_rq_bw() gets called (!task_on_rq_queued() branch) and the latter sees running_bw > this_bw. Fix it by removing a task contribution from running_bw if the task is not queued and in non_contending state while switched to a different class. Reported-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Juri Lelli <juri.lelli@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> Reviewed-by: Luca Abeni <luca.abeni@santannapisa.it> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: claudio@evidence.eu.com Cc: rostedt@goodmis.org Link: http://lkml.kernel.org/r/20180711072948.27061-1-juri.lelli@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15Merge tag 'v4.18-rc5' into sched/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-15stop_machine: Disable preemption when waking two stopper threadsIsaac J. Manjarres
When cpu_stop_queue_two_works() begins to wake the stopper threads, it does so without preemption disabled, which leads to the following race condition: The source CPU calls cpu_stop_queue_two_works(), with cpu1 as the source CPU, and cpu2 as the destination CPU. When adding the stopper threads to the wake queue used in this function, the source CPU stopper thread is added first, and the destination CPU stopper thread is added last. When wake_up_q() is invoked to wake the stopper threads, the threads are woken up in the order that they are queued in, so the source CPU's stopper thread is woken up first, and it preempts the thread running on the source CPU. The stopper thread will then execute on the source CPU, disable preemption, and begin executing multi_cpu_stop(), and wait for an ack from the destination CPU's stopper thread, with preemption still disabled. Since the worker thread that woke up the stopper thread on the source CPU is affine to the source CPU, and preemption is disabled on the source CPU, that thread will never run to dequeue the destination CPU's stopper thread from the wake queue, and thus, the destination CPU's stopper thread will never run, causing the source CPU's stopper thread to wait forever, and stall. Disable preemption when waking the stopper threads in cpu_stop_queue_two_works(). Fixes: 0b26351b910f ("stop_machine, sched: Fix migrate_swap() vs. active_balance() deadlock") Co-Developed-by: Prasad Sodagudi <psodagud@codeaurora.org> Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org> Co-Developed-by: Pavankumar Kondeti <pkondeti@codeaurora.org> Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org> Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: matt@codeblueprint.co.uk Cc: bigeasy@linutronix.de Cc: gregkh@linuxfoundation.org Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/1530655334-4601-1-git-send-email-isaacm@codeaurora.org
2018-07-13Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: "A clocksource driver fix and a revert" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: arm_arch_timer: Set arch_mem_timer cpumask to cpu_possible_mask Revert "tick: Prefer a lower rating device only if it's CPU local device"
2018-07-13Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull rseq fixes from Ingo Molnar: "Various rseq ABI fixes and cleanups: use get_user()/put_user(), validate parameters and use proper uapi types, etc" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rseq/selftests: cleanup: Update comment above rseq_prepare_unload rseq: Remove unused types_32_64.h uapi header rseq: uapi: Declare rseq_cs field as union, update includes rseq: uapi: Update uapi comments rseq: Use get_user/put_user rather than __get_user/__put_user rseq: Use __u64 for rseq_cs fields, validate user inputs
2018-07-13Merge tag 'trace-v4.18-rc3-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixlet from Steven Rostedt: "Joel Fernandes asked to add a feature in tracing that Android had its own patch internally for. I took it back in 4.13. Now he realizes that he had a mistake, and swapped the values from what Android had. This means that the old Android tools will break when using a new kernel that has the new feature on it. The options are: 1. To swap it back to what Android wants. 2. Add a command line option or something to do the swap 3. Just let Android carry a patch that swaps it back Since it requires setting a tracing option to enable this anyway, I doubt there are other users of this than Android. Thus, I've decided to take option 1. If someone else is actually depending on the order that is in the kernel, then we will have to revert this change and go to option 2 or 3" * tag 'trace-v4.18-rc3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Reorder display of TGID to be after PID
2018-07-12tracing: Reorder display of TGID to be after PIDJoel Fernandes (Google)
Currently ftrace displays data in trace output like so: _-----=> irqs-off / _----=> need-resched | / _---=> hardirq/softirq || / _--=> preempt-depth ||| / delay TASK-PID CPU TGID |||| TIMESTAMP FUNCTION | | | | |||| | | bash-1091 [000] ( 1091) d..2 28.313544: sched_switch: However Android's trace visualization tools expect a slightly different format due to an out-of-tree patch patch that was been carried for a decade, notice that the TGID and CPU fields are reversed: _-----=> irqs-off / _----=> need-resched | / _---=> hardirq/softirq || / _--=> preempt-depth ||| / delay TASK-PID TGID CPU |||| TIMESTAMP FUNCTION | | | | |||| | | bash-1091 ( 1091) [002] d..2 64.965177: sched_switch: From kernel v4.13 onwards, during which TGID was introduced, tracing with systrace on all Android kernels will break (most Android kernels have been on 4.9 with Android patches, so this issues hasn't been seen yet). From v4.13 onwards things will break. The chrome browser's tracing tools also embed the systrace viewer which uses the legacy TGID format and updates to that are known to be difficult to make. Considering this, I suggest we make this change to the upstream kernel and backport it to all Android kernels. I believe this feature is merged recently enough into the upstream kernel that it shouldn't be a problem. Also logically, IMO it makes more sense to group the TGID with the TASK-PID and the CPU after these. Link: http://lkml.kernel.org/r/20180626000822.113931-1-joel@joelfernandes.org Cc: jreck@google.com Cc: tkjos@google.com Cc: stable@vger.kernel.org Fixes: 441dae8f2f29 ("tracing: Add support for display of tgid in trace output") Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-12Merge branches 'fixes1.2018.07.12b' and 'torture1.2018.07.12b' into HEADPaul E. McKenney
fixes1.2018.07.12b: Post-gp_seq miscellaneous fixes torture1.2018.07.12b: Post-gp_seq torture-test updates
2018-07-12rcutorture: Fix rcu_barrier successes counterJoel Fernandes (Google)
The rcutorture test module currently increments both successes and error for the barrier test upon error, which results in misleading statistics being printed. This commit therefore changes the code to increment the success counter only when the test actually passes. This change was tested by by returning from the barrier callback without incrementing the callback counter, thus introducing what appeared to rcutorture to be rcu_barrier() failures. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12rcutorture: Add support to detect if boost kthread prio is too lowJoel Fernandes (Google)
When rcutorture is built in to the kernel, an earlier patch detects that and raises the priority of RCU's kthreads to allow rcutorture's RCU priority boosting tests to succeed. However, if rcutorture is built as a module, those priorities must be raised manually via the rcutree.kthread_prio kernel boot parameter. If this manual step is not taken, rcutorture's RCU priority boosting tests will fail due to kthread starvation. One approach would be to raise the default priority, but that risks breaking existing users. Another approach would be to allow runtime adjustment of RCU's kthread priorities, but that introduces numerous "interesting" race conditions. This patch therefore instead detects too-low priorities, and prints a message and disables the RCU priority boosting tests in that case. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12rcutorture: Use monotonic timestamp for stall detectionArnd Bergmann
The get_seconds() call is deprecated because it overflows on 32-bit architectures. The algorithm in rcu_torture_stall() can deal with the overflow, but another problem here is that using a CLOCK_REALTIME stamp can lead to a false-positive stall warning when a settimeofday() happens concurrently. Using ktime_get_seconds() instead avoids those issues and will never overflow. The added cast to 'unsigned long' however is necessary to make ULONG_CMP_LT() work correctly. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12rcutorture: Make boost test more robustJoel Fernandes (Google)
Currently, with RCU_BOOST disabled, I get no failures when forcing rcutorture to test RCU boost priority inversion. The reason seems to be that we don't check for failures if the callback never ran at all for the duration of the boost-test loop. Further, the 'rtb' and 'rtbf' counters seem to be used inconsistently. 'rtb' is incremented at the start of each test and 'rtbf' is incremented per-cpu on each failure of call_rcu. So its possible 'rtbf' > 'rtb'. To test the boost with rcutorture, I did following on a 4-CPU x86 machine: modprobe rcutorture test_boost=2 sleep 20 rmmod rcutorture With patch: rtbf: 8 rtb: 12 Without patch: rtbf: 0 rtb: 2 In summary this patch: - Increments failed and total test counters once per boost-test. - Checks for failure cases correctly. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12rcutorture: Disable RT throttling for boost testsJoel Fernandes (Google)
Currently rcutorture is not able to torture RCU boosting properly. This is because the rcutorture's boost threads which are doing the torturing may be throttled due to RT throttling. This patch makes rcutorture use the right torture technique (unthrottled rcutorture boost tasks) for torturing RCU so that the test fails correctly when no boost is available. Currently this requires accessing sysctl_sched_rt_runtime directly, but that should be Ok since rcutorture is test code. Such direct access is also only possible if rcutorture is used as a built-in so make it conditional on that. Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12rcutorture: Emphasize testing of single reader protection typePaul E. McKenney
For RCU implementations supporting multiple types of reader protection, rcutorture currently randomly selects the combinations of types of protection for each phase of each reader. The problem with this, for example, given the four kinds of protection for RCU-sched (local_irq_disable(), local_bh_disable(), preempt_disable(), and rcu_read_lock_sched()), the reader will be protected by a single mechanism only 25% of the time. We really heavier testing of single read-side mechanisms. This commit therefore uses only a single mechanism about 60% of the time, half of the time explicitly and one-eighth of the time by chance. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12rcutorture: Handle extended read-side critical sectionsPaul E. McKenney
This commit enables rcutorture to test whether RCU properly aggregates different types of read-side critical sections into a larger section covering the set. It does this by extending an initial read-side critical section randomly for a random number of extensions. There is a new rcu_torture_ops field ->extendable that specifies what extensions are permitted for a given flavor of RCU (for example, SRCU does not permit any extensions, while RCU-sched permits all types). Note that if a given operation (for example, local_bh_disable()) extends an RCU read-side critical section, then rcutorture feels free to also start and end the critical section with that operation's type of disabling. Disabling operations include local_bh_disable(), local_irq_disable(), and preempt_disable(). This commit also adds a new "busted_srcud" torture type, which verifies rcutorture's ability to detect extensions of RCU read-side critical sections that are not handled. Gotta test the test, after all! Note that it is not legal to invoke local_bh_disable() with interrupts disabled, and this transition is avoided by overriding the random-number generator when it wants to call local_bh_disable() while interrupts are disabled. The code instead leaves both interrupts and bh/softirq disabled in this case. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>