From: John Garry <john.garry@huawei.com>
To: Ming Lei <ming.lei@redhat.com>
Cc: <tglx@linutronix.de>, <chenxiang66@hisilicon.com>,
<bigeasy@linutronix.de>, <linux-kernel@vger.kernel.org>,
<maz@kernel.org>, <hare@suse.com>, <hch@lst.de>,
<axboe@kernel.dk>, <bvanassche@acm.org>, <peterz@infradead.org>,
<mingo@redhat.com>
Subject: Re: [PATCH RFC 1/1] genirq: Make threaded handler use irq affinity for managed interrupt
Date: Wed, 11 Dec 2019 17:09:18 +0000 [thread overview]
Message-ID: <0ad37515-c22d-6857-65a2-cc28256a8afa@huawei.com> (raw)
In-Reply-To: <20191210014335.GA25022@ming.t460p>
On 10/12/2019 01:43, Ming Lei wrote:
>>>> For when the interrupt is managed, allow the threaded part to run on all
>>>> cpus in the irq affinity mask.
>>> I remembered that performance drop is observed by this approach in some
>>> test.
>> From checking the thread about the NVMe interrupt swamp, just switching to
>> threaded handler alone degrades performance. I didn't see any specific
>> results for this change from Long Li -https://lkml.org/lkml/2019/8/21/128
Hi Ming,
> I am pretty clear the reason for Azure, which is caused by aggressive interrupt
> coalescing, and this behavior shouldn't be very common, and it can be
> addressed by the following patch:
I am running some NVMe perf tests with Marc's patch.
I see this almost always eventually (with or without that patch):
[ 66.018140] rcu: INFO: rcu_preempt self-detected stall on CPU2% done]
[5058MB/0KB/0KB /s] [1295K/0/0 iops] [eta 01m:39s]
[ 66.023885] rcu: 12-....: (5250 ticks this GP)
idle=182/1/0x4000000000000004 softirq=517/517 fqs=2529
[ 66.033306] (t=5254 jiffies g=733 q=2241)
[ 66.037394] Task dump for CPU 12:
[ 66.040696] fio R running task 0 798 796
0x00000002
[ 66.047733] Call trace:
[ 66.050173] dump_backtrace+0x0/0x1a0
[ 66.053823] show_stack+0x14/0x20
[ 66.057126] sched_show_task+0x164/0x1a0
[ 66.061036] dump_cpu_task+0x40/0x2e8
[ 66.064686] rcu_dump_cpu_stacks+0xa0/0xe0
[ 66.068769] rcu_sched_clock_irq+0x6d8/0xaa8
[ 66.073027] update_process_times+0x2c/0x50
[ 66.077198] tick_sched_handle.isra.14+0x30/0x50
[ 66.081802] tick_sched_timer+0x48/0x98
[ 66.085625] __hrtimer_run_queues+0x120/0x1b8
[ 66.089968] hrtimer_interrupt+0xd4/0x250
[ 66.093966] arch_timer_handler_phys+0x28/0x40
[ 66.098398] handle_percpu_devid_irq+0x80/0x140
[ 66.102915] generic_handle_irq+0x24/0x38
[ 66.106911] __handle_domain_irq+0x5c/0xb0
[ 66.110995] gic_handle_irq+0x5c/0x148
[ 66.114731] el1_irq+0xb8/0x180
[ 66.117858] efi_header_end+0x94/0x234
[ 66.121595] irq_exit+0xd0/0xd8
[ 66.124724] __handle_domain_irq+0x60/0xb0
[ 66.128806] gic_handle_irq+0x5c/0x148
[ 66.132542] el0_irq_naked+0x4c/0x54
[ 97.152870] rcu: INFO: rcu_preempt self-detected stall on CPU8% done]
[4736MB/0KB/0KB /s] [1212K/0/0 iops] [eta 01m:08s]
[ 97.158616] rcu: 8-....: (1 GPs behind) idle=08e/1/0x4000000000000002
softirq=462/505 fqs=2621
[ 97.167414] (t=5253 jiffies g=737 q=5507)
[ 97.171498] Task dump for CPU 8:
[pu_task+0x40/0x2e8
[ 97.198705] rcu_dump_cpu_stacks+0xa0/0xe0
[ 97.202788] rcu_sched_clock_irq+0x6d8/0xaa8
[ 97.207046] update_process_times+0x2c/0x50
[ 97.211217] tick_sched_handle.isra.14+0x30/0x50
[ 97.215820] tick_sched_timer+0x48/0x98
[ 97.219644] __hrtimer_run_queues+0x120/0x1b8
[ 97.223989] hrtimer_interrupt+0xd4/0x250
[ 97.227987] arch_timer_handler_phys+0x28/0x40
[ 97.232418] handle_percpu_devid_irq+0x80/0x140
[ 97.236935] generic_handle_irq+0x24/0x38
[ 97.240931] __handle_domain_irq+0x5c/0xb0
[ 97.245015] gic_handle_irq+0x5c/0x148
[ 97.248751] el1_irq+0xb8/0x180
[ 97.251880] find_busiest_group+0x18c/0x9e8
[ 97.256050] load_balance+0x154/0xb98
[ 97.259700] rebalance_domains+0x1cc/0x2f8
[ 97.263783] run_rebalance_domains+0x78/0xe0
[ 97.268040] efi_header_end+0x114/0x234
[ 97.271864] run_ksoftirqd+0x38/0x48
[ 97.275427] smpboot_thread_fn+0x16c/0x270
[ 97.279511] kthread+0x118/0x120
[ 97.282726] ret_from_fork+0x10/0x18
[ 97.286289] Task dump for CPU 12:
[ 97.289591] kworker/12:1 R running task 0 570 2
0x0000002a
[ 97.296634] Workqueue: 0x0 (mm_percpu_wq)
[ 97.300718] Call trace:
[ 97.303152] __switch_to+0xbc/0x218
[ 97.306632] page_wait_table+0x1500/0x1800
Would this be the same interrupt "swamp" issue?
>
> http://lists.infradead.org/pipermail/linux-nvme/2019-November/028008.html
>
What is the status of these patches? I did not see them in mainline.
> Then please share your lockup story, such as, which HBA/drivers, test steps,
> if you complete IOs from multiple disks(LUNs) on single CPU, if you have
> multiple queues, how many active LUNs involved in the test, ...
>
>
Thanks,
John
next prev parent reply other threads:[~2019-12-11 17:09 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-06 14:35 [PATCH RFC 0/1] Threaded handler uses irq affinity for when the interrupt is managed John Garry
2019-12-06 14:35 ` [PATCH RFC 1/1] genirq: Make threaded handler use irq affinity for managed interrupt John Garry
2019-12-06 15:22 ` Marc Zyngier
2019-12-06 16:16 ` John Garry
2019-12-07 8:03 ` Ming Lei
2019-12-09 14:30 ` John Garry
2019-12-09 15:09 ` Hannes Reinecke
2019-12-09 15:17 ` Marc Zyngier
2019-12-09 15:25 ` Hannes Reinecke
2019-12-09 15:36 ` Marc Zyngier
2019-12-09 15:49 ` Qais Yousef
2019-12-09 15:55 ` Marc Zyngier
2019-12-10 1:43 ` Ming Lei
2019-12-10 9:45 ` John Garry
2019-12-10 10:06 ` Ming Lei
2019-12-10 10:28 ` Marc Zyngier
2019-12-10 10:59 ` John Garry
2019-12-10 11:36 ` Marc Zyngier
2019-12-10 12:05 ` John Garry
2019-12-10 18:32 ` Marc Zyngier
2019-12-11 9:41 ` John Garry
2019-12-13 10:07 ` John Garry
2019-12-13 10:31 ` Marc Zyngier
2019-12-13 12:08 ` John Garry
2019-12-14 10:59 ` Marc Zyngier
2019-12-11 17:09 ` John Garry [this message]
2019-12-12 22:38 ` Ming Lei
2019-12-13 11:12 ` John Garry
2019-12-13 13:18 ` Ming Lei
2019-12-13 15:43 ` John Garry
2019-12-13 17:12 ` Ming Lei
2019-12-13 17:50 ` John Garry
2019-12-14 13:56 ` Marc Zyngier
2019-12-16 10:47 ` John Garry
2019-12-16 11:40 ` Marc Zyngier
2019-12-16 14:17 ` John Garry
2019-12-16 18:00 ` Marc Zyngier
2019-12-16 18:50 ` John Garry
2019-12-20 11:30 ` John Garry
2019-12-20 14:43 ` Marc Zyngier
2019-12-20 15:38 ` John Garry
2019-12-20 16:16 ` Marc Zyngier
2019-12-20 23:31 ` Ming Lei
2019-12-23 9:07 ` Marc Zyngier
2019-12-23 10:26 ` John Garry
2019-12-23 10:47 ` Marc Zyngier
2019-12-23 11:35 ` John Garry
2019-12-24 1:59 ` Ming Lei
2019-12-24 11:20 ` Marc Zyngier
2019-12-25 0:48 ` Ming Lei
2020-01-02 10:35 ` John Garry
2020-01-03 0:46 ` Ming Lei
2020-01-03 10:41 ` John Garry
2020-01-03 11:29 ` Ming Lei
2020-01-03 11:50 ` John Garry
2020-01-04 12:03 ` Ming Lei
2020-05-30 7:46 ` [tip: irq/core] irqchip/gic-v3-its: Balance initial LPI affinity across CPUs tip-bot2 for Marc Zyngier
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=0ad37515-c22d-6857-65a2-cc28256a8afa@huawei.com \
--to=john.garry@huawei.com \
--cc=axboe@kernel.dk \
--cc=bigeasy@linutronix.de \
--cc=bvanassche@acm.org \
--cc=chenxiang66@hisilicon.com \
--cc=hare@suse.com \
--cc=hch@lst.de \
--cc=linux-kernel@vger.kernel.org \
--cc=maz@kernel.org \
--cc=ming.lei@redhat.com \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).