All of lore.kernel.org
 help / color / mirror / Atom feed
From: Vinayak Menon <vinmenon@codeaurora.org>
To: Johannes Weiner <hannes@cmpxchg.org>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	linux-block@vger.kernel.org, cgroups@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Andrew Morton <akpm@linuxfoundation.org>,
	Tejun Heo <tj@kernel.org>, Balbir Singh <bsingharora@gmail.com>,
	Mike Galbraith <efault@gmx.de>, Oliver Yang <yangoliver@me.com>,
	Shakeel Butt <shakeelb@google.com>, xxx xxx <x.qendo@gmail.com>,
	Taras Kondratiuk <takondra@cisco.com>,
	Daniel Walker <danielwa@cisco.com>,
	Ruslan Ruslichenko <rruslich@cisco.com>,
	kernel-team@fb.com
Subject: Re: [PATCH 6/7] psi: pressure stall information for CPU, memory, and IO
Date: Wed, 9 May 2018 16:33:24 +0530	[thread overview]
Message-ID: <87060553-2e09-2e2a-13a2-a91345d6df30@codeaurora.org> (raw)
In-Reply-To: <20180507210135.1823-7-hannes@cmpxchg.org>


On 5/8/2018 2:31 AM, Johannes Weiner wrote:
> +static void psi_group_update(struct psi_group *group, int cpu, u64 now,
> +			     unsigned int clear, unsigned int set)
> +{
> +	enum psi_state state = PSI_NONE;
> +	struct psi_group_cpu *groupc;
> +	unsigned int *tasks;
> +	unsigned int to, bo;
> +
> +	groupc = per_cpu_ptr(group->cpus, cpu);
> +	tasks = groupc->tasks;
> +
> +	/* Update task counts according to the set/clear bitmasks */
> +	for (to = 0; (bo = ffs(clear)); to += bo, clear >>= bo) {
> +		int idx = to + (bo - 1);
> +
> +		if (tasks[idx] == 0 && !psi_bug) {
> +			printk_deferred(KERN_ERR "psi: task underflow! cpu=%d idx=%d tasks=[%u %u %u %u]\n",
> +					cpu, idx, tasks[0], tasks[1],
> +					tasks[2], tasks[3]);
> +			psi_bug = 1;
> +		}
> +		tasks[idx]--;
> +	}
> +	for (to = 0; (bo = ffs(set)); to += bo, set >>= bo)
> +		tasks[to + (bo - 1)]++;
> +
> +	/* Time in which tasks wait for the CPU */
> +	state = PSI_NONE;
> +	if (tasks[NR_RUNNING] > 1)
> +		state = PSI_SOME;
> +	time_state(&groupc->res[PSI_CPU], state, now);
> +
> +	/* Time in which tasks wait for memory */
> +	state = PSI_NONE;
> +	if (tasks[NR_MEMSTALL]) {
> +		if (!tasks[NR_RUNNING] ||
> +		    (cpu_curr(cpu)->flags & PF_MEMSTALL))
> +			state = PSI_FULL;
> +		else
> +			state = PSI_SOME;
> +	}
> +	time_state(&groupc->res[PSI_MEM], state, now);
> +
> +	/* Time in which tasks wait for IO */
> +	state = PSI_NONE;
> +	if (tasks[NR_IOWAIT]) {
> +		if (!tasks[NR_RUNNING])
> +			state = PSI_FULL;
> +		else
> +			state = PSI_SOME;
> +	}
> +	time_state(&groupc->res[PSI_IO], state, now);
> +
> +	/* Time in which tasks are non-idle, to weigh the CPU in summaries */
> +	if (groupc->nonidle)
> +		groupc->nonidle_time += now - groupc->nonidle_start;
> +	groupc->nonidle = tasks[NR_RUNNING] ||
> +		tasks[NR_IOWAIT] || tasks[NR_MEMSTALL];
> +	if (groupc->nonidle)
> +		groupc->nonidle_start = now;
> +
> +	/* Kick the stats aggregation worker if it's gone to sleep */
> +	if (!delayed_work_pending(&group->clock_work))

This causes a crash when the work is scheduled before system_wq is up. In my case when the first
schedule was called from kthreadd. And I had to do this to make it work.
if (keventd_up() && !delayed_work_pending(&group->clock_work))

> +		schedule_delayed_work(&group->clock_work, MY_LOAD_FREQ);
> +}
> +
> +void psi_task_change(struct task_struct *task, u64 now, int clear, int set)
> +{
> +	struct cgroup *cgroup, *parent;

unused variables

Thanks,
Vinayak

  parent reply	other threads:[~2018-05-09 11:03 UTC|newest]

Thread overview: 44+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-07 21:01 [PATCH 0/7] " Johannes Weiner
2018-05-07 21:01 ` [PATCH 1/7] mm: workingset: don't drop refault information prematurely Johannes Weiner
2018-05-07 21:01 ` [PATCH 2/7] mm: workingset: tell cache transitions from workingset thrashing Johannes Weiner
2018-05-07 21:01 ` [PATCH 3/7] delayacct: track delays from thrashing cache pages Johannes Weiner
2018-05-07 21:01 ` [PATCH 4/7] sched: loadavg: consolidate LOAD_INT, LOAD_FRAC, CALC_LOAD Johannes Weiner
2018-05-07 21:01 ` [PATCH 5/7] sched: loadavg: make calc_load_n() public Johannes Weiner
2018-05-09  9:49   ` Peter Zijlstra
2018-05-10 13:46     ` Johannes Weiner
2018-05-07 21:01 ` [PATCH 6/7] psi: pressure stall information for CPU, memory, and IO Johannes Weiner
2018-05-08  0:42   ` Randy Dunlap
2018-05-08 14:06     ` Johannes Weiner
2018-05-08  1:35   ` kbuild test robot
2018-05-08  3:04   ` kbuild test robot
2018-05-08 14:05     ` Johannes Weiner
2018-05-09  9:59   ` Peter Zijlstra
2018-05-10 13:49     ` Johannes Weiner
2018-05-09 10:04   ` Peter Zijlstra
2018-05-10 14:10     ` Johannes Weiner
2018-05-09 10:05   ` Peter Zijlstra
2018-05-10 14:13     ` Johannes Weiner
2018-05-09 10:14   ` Peter Zijlstra
2018-05-10 14:18     ` Johannes Weiner
2018-05-09 10:21   ` Peter Zijlstra
2018-05-10 14:24     ` Johannes Weiner
2018-05-09 10:26   ` Peter Zijlstra
2018-05-09 10:46   ` Peter Zijlstra
2018-05-09 11:38     ` Peter Zijlstra
2018-05-10 13:41       ` Johannes Weiner
2018-05-14  8:33         ` Peter Zijlstra
2018-05-09 10:55   ` Peter Zijlstra
2018-05-09 11:03   ` Vinayak Menon [this message]
2018-05-23 13:17     ` Johannes Weiner
2018-05-23 13:19       ` Vinayak Menon
2018-06-07  0:46   ` Suren Baghdasaryan
2018-05-07 21:01 ` [PATCH 7/7] psi: cgroup support Johannes Weiner
2018-05-09 11:07   ` Peter Zijlstra
2018-05-10 14:49     ` Johannes Weiner
2018-05-14 15:39 ` [PATCH 0/7] psi: pressure stall information for CPU, memory, and IO Christopher Lameter
2018-05-14 17:35   ` Bart Van Assche
2018-05-14 18:55   ` Johannes Weiner
2018-05-14 20:15     ` Christopher Lameter
2018-05-26  0:29 ` Suren Baghdasaryan
2018-05-29 18:16   ` Johannes Weiner
2018-05-30 23:32     ` Suren Baghdasaryan

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=87060553-2e09-2e2a-13a2-a91345d6df30@codeaurora.org \
    --to=vinmenon@codeaurora.org \
    --cc=akpm@linuxfoundation.org \
    --cc=bsingharora@gmail.com \
    --cc=cgroups@vger.kernel.org \
    --cc=danielwa@cisco.com \
    --cc=efault@gmx.de \
    --cc=hannes@cmpxchg.org \
    --cc=kernel-team@fb.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.org \
    --cc=rruslich@cisco.com \
    --cc=shakeelb@google.com \
    --cc=takondra@cisco.com \
    --cc=tj@kernel.org \
    --cc=x.qendo@gmail.com \
    --cc=yangoliver@me.com \
    --subject='Re: [PATCH 6/7] psi: pressure stall information for CPU, memory, and IO' \
    /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

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.