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[209.132.180.67]) by mx.google.com with ESMTP id x66si6064250ota.244.2020.03.30.04.06.23; Mon, 30 Mar 2020 04:06:37 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729779AbgC3LGE convert rfc822-to-8bit (ORCPT + 99 others); Mon, 30 Mar 2020 07:06:04 -0400 Received: from mail.fireflyinternet.com ([109.228.58.192]:56311 "EHLO fireflyinternet.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729448AbgC3LGD (ORCPT ); Mon, 30 Mar 2020 07:06:03 -0400 X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from localhost (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP (TLS) id 20738601-1500050 for multiple; Mon, 30 Mar 2020 12:05:44 +0100 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT In-Reply-To: <158029757853.396.10568128383380430250.tip-bot2@tip-bot2> References: <20200122151617.531-2-ggherdovich@suse.cz> <158029757853.396.10568128383380430250.tip-bot2@tip-bot2> Cc: Peter Zijlstra , Giovanni Gherdovich , Ingo Molnar , Doug Smythies , "Rafael J. Wysocki" , x86 , LKML To: linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org, tip-bot2 for Giovanni Gherdovich Subject: Re: [tip: sched/core] x86, sched: Add support for frequency invariance From: Chris Wilson Message-ID: <158556634294.3228.4889951961483021094@build.alporthouse.com> User-Agent: alot/0.8.1 Date: Mon, 30 Mar 2020 12:05:42 +0100 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Quoting tip-bot2 for Giovanni Gherdovich (2020-01-29 11:32:58) > The following commit has been merged into the sched/core branch of tip: > > Commit-ID: 1567c3e3467cddeb019a7b53ec632f834b6a9239 > Gitweb: https://git.kernel.org/tip/1567c3e3467cddeb019a7b53ec632f834b6a9239 > Author: Giovanni Gherdovich > AuthorDate: Wed, 22 Jan 2020 16:16:12 +01:00 > Committer: Ingo Molnar > CommitterDate: Tue, 28 Jan 2020 21:36:59 +01:00 > > x86, sched: Add support for frequency invariance > diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c > index 69881b2..28696bc 100644 > --- a/arch/x86/kernel/smpboot.c > +++ b/arch/x86/kernel/smpboot.c > @@ -147,6 +147,8 @@ static inline void smpboot_restore_warm_reset_vector(void) > *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0; > } > > +static void init_freq_invariance(void); > + > /* > * Report back to the Boot Processor during boot time or to the caller processor > * during CPU online. > @@ -183,6 +185,8 @@ static void smp_callin(void) > */ > set_cpu_sibling_map(raw_smp_processor_id()); > > + init_freq_invariance(); > + > /* > * Get our bogomips. > * Update loops_per_jiffy in cpu_data. Previous call to > @@ -1337,7 +1341,7 @@ void __init native_smp_prepare_cpus(unsigned int max_cpus) > set_sched_topology(x86_topology); > > set_cpu_sibling_map(0); > - > + init_freq_invariance(); > smp_sanity_check(); > > switch (apic_intr_mode) { Since this has become visible via linux-next [20200326?], we have been deluged by oops during cpu-hotplug. <6> [184.949219] [IGT] perf_pmu: starting subtest cpu-hotplug <4> [185.092279] IRQ 24: no longer affine to CPU0 <4> [185.092285] IRQ 25: no longer affine to CPU0 <6> [185.093709] smpboot: CPU 0 is now offline <6> [186.107062] smpboot: Booting Node 0 Processor 0 APIC 0x0 <3> [186.107643] BUG: sleeping function called from invalid context at ./include/linux/percpu-rwsem.h:49 <3> [186.107648] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 0, name: swapper/0 <4> [186.107650] no locks held by swapper/0/0. <4> [186.107652] irq event stamp: 6424624 <4> [186.107658] hardirqs last enabled at (6424623): [] tick_nohz_idle_enter+0x5f/0x90 <4> [186.107664] hardirqs last disabled at (6424624): [] do_idle+0x82/0x260 <4> [186.107669] softirqs last enabled at (6424590): [] __do_softirq+0x395/0x49e <4> [186.107674] softirqs last disabled at (6424571): [] irq_exit+0xba/0xc0 <3> [186.107677] Preemption disabled at: <4> [186.107681] [] start_secondary+0x4b/0x1b0 <4> [186.107685] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U 5.6.0-rc7-next-20200327-g975f7a88c64d-next-20200327 #1 <4> [186.107687] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 <4> [186.107688] Call Trace: <4> [186.107695] dump_stack+0x71/0x9b <4> [186.107702] ___might_sleep+0x178/0x260 <4> [186.107708] cpus_read_lock+0x13/0xd0 <4> [186.107713] static_key_enable+0x9/0x20 <4> [186.107717] init_freq_invariance+0x1f0/0x3a0 <4> [186.107724] start_secondary+0x71/0x1b0 <4> [186.107729] secondary_startup_64+0xb6/0xc0 <3> [186.107756] BUG: scheduling while atomic: swapper/0/0/0x00000002 <4> [186.107763] 1 lock held by swapper/0/0: <4> [186.107767] #0: ffffffff9643e510 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0x9/0x20 <4> [186.107775] Modules linked in: vgem snd_hda_codec_hdmi mei_hdcp i915 x86_pkg_temp_thermal coretemp snd_hda_codec_realtek snd_hda_codec_generic crct10dif_pclmul snd_hda_intel crc32_pclmul snd_intel_dspcfg ghash_clmulni_intel snd_hda_codec snd_hwdep snd_hda_core r8169 lpc_ich snd_pcm mei_me mei realtek prime_numbers <3> [186.107797] Preemption disabled at: <4> [186.107800] [] start_secondary+0x4b/0x1b0 <4> [186.107803] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U W 5.6.0-rc7-next-20200327-g975f7a88c64d-next-20200327 #1 <4> [186.107805] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 <4> [186.107807] Call Trace: <4> [186.107811] dump_stack+0x71/0x9b <4> [186.107815] ? start_secondary+0x4b/0x1b0 <4> [186.107819] __schedule_bug+0x7b/0xd0 <4> [186.107825] __schedule+0x776/0x810 <4> [186.107832] ? mark_held_locks+0x49/0x70 <4> [186.107839] schedule+0x37/0xe0 <4> [186.107843] ? percpu_rwsem_wait+0x117/0x180 <4> [186.107846] percpu_rwsem_wait+0x117/0x180 <4> [186.107851] ? percpu_down_write+0x140/0x140 <4> [186.107859] __percpu_down_read+0x43/0x60 <4> [186.107864] cpus_read_lock+0xc6/0xd0 <4> [186.107867] static_key_enable+0x9/0x20 <4> [186.107871] init_freq_invariance+0x1f0/0x3a0 <4> [186.107878] start_secondary+0x71/0x1b0 <4> [186.107883] secondary_startup_64+0xb6/0xc0 <4> [186.107900] ------------[ cut here ]------------ <4> [186.107901] releasing a pinned lock <4> [186.107908] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:4640 lock_release+0x2a2/0x2c0 <4> [186.107909] Modules linked in: vgem snd_hda_codec_hdmi mei_hdcp i915 x86_pkg_temp_thermal coretemp snd_hda_codec_realtek snd_hda_codec_generic crct10dif_pclmul snd_hda_intel crc32_pclmul snd_intel_dspcfg ghash_clmulni_intel snd_hda_codec snd_hwdep snd_hda_core r8169 lpc_ich snd_pcm mei_me mei realtek prime_numbers <4> [186.107924] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U W 5.6.0-rc7-next-20200327-g975f7a88c64d-next-20200327 #1 <4> [186.107926] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 <4> [186.107928] RIP: 0010:lock_release+0x2a2/0x2c0 <4> [186.107931] Code: be 3f 00 00 00 48 c7 c7 51 a7 2b 96 c6 05 68 6d 41 01 01 e8 40 8e ff ff eb ae 48 c7 c7 51 a8 2b 96 48 89 04 24 e8 be 0b f9 ff <0f> 0b 48 8b 04 24 e9 22 fe ff ff e8 4e 0e f9 ff 0f 1f 40 00 66 2e <4> [186.107933] RSP: 0018:ffffffff96403d88 EFLAGS: 00010086 <4> [186.107936] RAX: 0000000000000000 RBX: ffffffff964188c0 RCX: 0000000000000003 <4> [186.107937] RDX: 0000000080000003 RSI: ffffffff95138419 RDI: 00000000ffffffff <4> [186.107939] RBP: ffffa1290f83bc58 R08: 0000000000000001 R09: 0000000000000001 <4> [186.107940] R10: ffffffff96403dc0 R11: 0000000000077cc4 R12: 0000000000000046 <4> [186.107944] R13: ffffffff950fa029 R14: 0000000000000002 R15: 00000000d3a98c93 <4> [186.107947] FS: 0000000000000000(0000) GS:ffffa1290f800000(0000) knlGS:0000000000000000 <4> [186.107948] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [186.107950] CR2: 00007f307e92fb24 CR3: 0000000287410001 CR4: 00000000001606f0 <4> [186.107951] Call Trace: <4> [186.107956] _raw_spin_unlock_irq+0x12/0x40 <4> [186.107959] dequeue_task_idle+0x9/0x30 <4> [186.107962] __schedule+0x3cc/0x810 <4> [186.107965] schedule+0x37/0xe0 <4> [186.107969] ? percpu_rwsem_wait+0x117/0x180 <4> [186.107972] percpu_rwsem_wait+0x117/0x180 <4> [186.107975] ? percpu_down_write+0x140/0x140 <4> [186.107978] __percpu_down_read+0x43/0x60 <4> [186.107981] cpus_read_lock+0xc6/0xd0 <4> [186.107984] static_key_enable+0x9/0x20 <4> [186.107988] init_freq_invariance+0x1f0/0x3a0 <4> [186.107991] start_secondary+0x71/0x1b0 <4> [186.107993] secondary_startup_64+0xb6/0xc0 <4> [186.107997] irq event stamp: 6424720 <4> [186.108001] hardirqs last enabled at (6424719): [] dump_stack+0x93/0x9b <4> [186.108004] hardirqs last disabled at (6424720): [] __schedule+0xc4/0x810 <4> [186.108007] softirqs last enabled at (6424590): [] __do_softirq+0x395/0x49e <4> [186.108011] softirqs last disabled at (6424571): [] irq_exit+0xba/0xc0 <4> [186.108013] ---[ end trace 8ae0a00b9ac91c9b ]--- <3> [186.108015] bad: scheduling from the idle thread! <4> [186.108018] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U W 5.6.0-rc7-next-20200327-g975f7a88c64d-next-20200327 #1 <4> [186.108020] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 <4> [186.108022] Call Trace: <4> [186.108028] dump_stack+0x71/0x9b <4> [186.108033] dequeue_task_idle+0x1a/0x30 <4> [186.108036] __schedule+0x3cc/0x810 <4> [186.108047] schedule+0x37/0xe0 <4> [186.108050] ? percpu_rwsem_wait+0x117/0x180 <4> [186.108053] percpu_rwsem_wait+0x117/0x180 <4> [186.108059] ? percpu_down_write+0x140/0x140 <4> [186.108067] __percpu_down_read+0x43/0x60 <4> [186.108072] cpus_read_lock+0xc6/0xd0 <4> [186.108077] static_key_enable+0x9/0x20 <4> [186.108081] init_freq_invariance+0x1f0/0x3a0 <4> [186.108089] start_secondary+0x71/0x1b0 <4> [186.108094] secondary_startup_64+0xb6/0xc0 <4> [186.108112] ------------[ cut here ]------------ <4> [186.108112] unpinning an unpinned lock <4> [186.108117] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:4768 lock_unpin_lock+0x11e/0x130 <4> [186.108119] Modules linked in: vgem snd_hda_codec_hdmi mei_hdcp i915 x86_pkg_temp_thermal coretemp snd_hda_codec_realtek snd_hda_codec_generic crct10dif_pclmul snd_hda_intel crc32_pclmul snd_intel_dspcfg ghash_clmulni_intel snd_hda_codec snd_hwdep snd_hda_core r8169 lpc_ich snd_pcm mei_me mei realtek prime_numbers <4> [186.108133] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U W 5.6.0-rc7-next-20200327-g975f7a88c64d-next-20200327 #1 <4> [186.108134] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 <4> [186.108136] RIP: 0010:lock_unpin_lock+0x11e/0x130 <4> [186.108138] Code: 96 e8 86 01 f9 ff 0f 0b e9 37 ff ff ff 0f 0b c7 82 bc 08 00 00 00 00 00 00 e9 3c ff ff ff 48 c7 c7 90 a8 2b 96 e8 62 01 f9 ff <0f> 0b e9 13 ff ff ff 90 66 2e 0f 1f 84 00 00 00 00 00 44 8b 0d 4d <4> [186.108139] RSP: 0018:ffffffff96403db0 EFLAGS: 00010086 <4> [186.108140] RAX: 0000000000000000 RBX: ffffffff964191a8 RCX: 0000000000000003 <4> [186.108141] RDX: 0000000080000003 RSI: ffffffff95138419 RDI: 00000000ffffffff <4> [186.108142] RBP: ffffffff964188c0 R08: 0000000000000001 R09: 0000000000000001 <4> [186.108143] R10: 00000000e6f5d832 R11: 0000000000078b54 R12: ffffa1290f83bc58 <4> [186.108144] R13: ffffffff96419180 R14: 0000000000000046 R15: 0000000000000001 <4> [186.108145] FS: 0000000000000000(0000) GS:ffffa1290f800000(0000) knlGS:0000000000000000 <4> [186.108146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [186.108147] CR2: 00007f307e92fb24 CR3: 0000000287410001 CR4: 00000000001606f0 <4> [186.108147] Call Trace: <4> [186.108151] __schedule+0x747/0x810 <4> [186.108154] schedule+0x37/0xe0 <4> [186.108156] ? percpu_rwsem_wait+0x117/0x180 <4> [186.108157] percpu_rwsem_wait+0x117/0x180 <4> [186.108160] ? percpu_down_write+0x140/0x140 <4> [186.108162] __percpu_down_read+0x43/0x60 <4> [186.108165] cpus_read_lock+0xc6/0xd0 <4> [186.108167] static_key_enable+0x9/0x20 <4> [186.108171] init_freq_invariance+0x1f0/0x3a0 <4> [186.108173] start_secondary+0x71/0x1b0 <4> [186.108175] secondary_startup_64+0xb6/0xc0 <4> [186.108178] irq event stamp: 6424730 <4> [186.108181] hardirqs last enabled at (6424729): [] dump_stack+0x93/0x9b <4> [186.108183] hardirqs last disabled at (6424730): [] _raw_spin_lock_irq+0xa/0x40 <4> [186.108185] softirqs last enabled at (6424590): [] __do_softirq+0x395/0x49e <4> [186.108188] softirqs last disabled at (6424571): [] irq_exit+0xba/0xc0 <4> [186.108188] ---[ end trace 8ae0a00b9ac91c9c ]--- <4> [186.108191] ------------[ cut here ]------------ <4> [186.108191] releasing a pinned lock <4> [186.108196] WARNING: CPU: 0 PID: 0 at kernel/locking/lockdep.c:4640 lock_release+0x2a2/0x2c0 <4> [186.108196] Modules linked in: vgem snd_hda_codec_hdmi mei_hdcp i915 x86_pkg_temp_thermal coretemp snd_hda_codec_realtek snd_hda_codec_generic crct10dif_pclmul snd_hda_intel crc32_pclmul snd_intel_dspcfg ghash_clmulni_intel snd_hda_codec snd_hwdep snd_hda_core r8169 lpc_ich snd_pcm mei_me mei realtek prime_numbers <4> [186.108204] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U W 5.6.0-rc7-next-20200327-g975f7a88c64d-next-20200327 #1 <4> [186.108205] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 <4> [186.108207] RIP: 0010:lock_release+0x2a2/0x2c0 <4> [186.108208] Code: be 3f 00 00 00 48 c7 c7 51 a7 2b 96 c6 05 68 6d 41 01 01 e8 40 8e ff ff eb ae 48 c7 c7 51 a8 2b 96 48 89 04 24 e8 be 0b f9 ff <0f> 0b 48 8b 04 24 e9 22 fe ff ff e8 4e 0e f9 ff 0f 1f 40 00 66 2e <4> [186.108209] RSP: 0018:ffffffff96403d88 EFLAGS: 00010086 <4> [186.108210] RAX: 0000000000000000 RBX: ffffffff964188c0 RCX: 0000000000000003 <4> [186.108211] RDX: 0000000080000003 RSI: ffffffff95138419 RDI: 00000000ffffffff <4> [186.108212] RBP: ffffa1290f83bc58 R08: 0000000000000001 R09: 0000000000000001 <4> [186.108213] R10: ffffffff96403dc0 R11: 00000000000795ac R12: 0000000000000046 <4> [186.108214] R13: ffffffff950fa029 R14: 0000000000000002 R15: 00000000d3a98c93 <4> [186.108215] FS: 0000000000000000(0000) GS:ffffa1290f800000(0000) knlGS:0000000000000000 <4> [186.108216] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 <4> [186.108217] CR2: 00007f307e92fb24 CR3: 0000000287410001 CR4: 00000000001606f0 <4> [186.108218] Call Trace: <4> [186.108221] _raw_spin_unlock_irq+0x12/0x40 <4> [186.108225] dequeue_task_idle+0x9/0x30 <4> [186.108227] __schedule+0x3cc/0x810 <4> [186.108230] schedule+0x37/0xe0 <4> [186.108232] ? percpu_rwsem_wait+0x117/0x180 <4> [186.108233] percpu_rwsem_wait+0x117/0x180 <4> [186.108235] ? percpu_down_write+0x140/0x140 <4> [186.108238] __percpu_down_read+0x43/0x60 <4> [186.108240] cpus_read_lock+0xc6/0xd0 <4> [186.108242] static_key_enable+0x9/0x20 <4> [186.108245] init_freq_invariance+0x1f0/0x3a0 <4> [186.108247] start_secondary+0x71/0x1b0 <4> [186.108249] secondary_startup_64+0xb6/0xc0 <4> [186.108252] irq event stamp: 6424732 <4> [186.108255] hardirqs last enabled at (6424731): [] _raw_spin_unlock_irq+0x1f/0x40 <4> [186.108257] hardirqs last disabled at (6424732): [] __schedule+0xc4/0x810 <4> [186.108258] softirqs last enabled at (6424590): [] __do_softirq+0x395/0x49e <4> [186.108261] softirqs last disabled at (6424571): [] irq_exit+0xba/0xc0 <4> [186.108262] ---[ end trace 8ae0a00b9ac91c9d ]--- <3> [186.108263] bad: scheduling from the idle thread! <4> [186.108266] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G U W 5.6.0-rc7-next-20200327-g975f7a88c64d-next-20200327 #1 <4> [186.108268] Hardware name: MSI MS-7924/Z97M-G43(MS-7924), BIOS V1.12 02/15/2016 <4> [186.108269] Call Trace: <4> [186.108273] dump_stack+0x71/0x9b <4> [186.108278] dequeue_task_idle+0x1a/0x30 <4> [186.108282] __schedule+0x3cc/0x810 <4> [186.108292] schedule+0x37/0xe0 <4> [186.108296] ? percpu_rwsem_wait+0x117/0x180 <4> [186.108298] percpu_rwsem_wait+0x117/0x180 <4> [186.108303] ? percpu_down_write+0x140/0x140 <4> [186.108311] __percpu_down_read+0x43/0x60 <4> [186.108316] cpus_read_lock+0xc6/0xd0 <4> [186.108319] static_key_enable+0x9/0x20 <4> [186.108323] init_freq_invariance+0x1f0/0x3a0 <4> [186.108330] start_secondary+0x71/0x1b0 <4> [186.108335] secondary_startup_64+0xb6/0xc0 <4> [186.108351] ------------[ cut here ]------------ repeating ad nauseam, e.g. https://intel-gfx-ci.01.org/tree/linux-next/next-20200327/shard-hsw4/dmesg9.txt Across all our test boxen. -Chris