linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: kan.liang@linux.intel.com
Cc: acme@kernel.org, mingo@redhat.com, linux-kernel@vger.kernel.org,
	tglx@linutronix.de, jolsa@kernel.org, eranian@google.com,
	alexander.shishkin@linux.intel.com, ak@linux.intel.com
Subject: Re: [PATCH V4 08/14] perf/x86/intel: Support per thread RDPMC TopDown metrics
Date: Mon, 30 Sep 2019 17:52:44 +0200	[thread overview]
Message-ID: <20190930155244.GP4553@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20190916134128.18120-9-kan.liang@linux.intel.com>

On Mon, Sep 16, 2019 at 06:41:22AM -0700, kan.liang@linux.intel.com wrote:
> diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
> index 71f3086a8adc..7ec0f350d2ac 100644
> --- a/arch/x86/events/intel/core.c
> +++ b/arch/x86/events/intel/core.c
> @@ -2262,6 +2262,11 @@ static int icl_set_topdown_event_period(struct perf_event *event)
>  		local64_set(&hwc->period_left, 0);
>  	}
>  
> +	if ((hwc->saved_slots) && is_first_topdown_event_in_group(event)) {
> +		wrmsrl(MSR_CORE_PERF_FIXED_CTR3, hwc->saved_slots);
> +		wrmsrl(MSR_PERF_METRICS, hwc->saved_metric);
> +	}

> diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
> index 61448c19a132..c125068f2e16 100644
> --- a/include/linux/perf_event.h
> +++ b/include/linux/perf_event.h
> @@ -133,6 +133,9 @@ struct hw_perf_event {
>  
>  			struct hw_perf_event_extra extra_reg;
>  			struct hw_perf_event_extra branch_reg;
> +
> +			u64		saved_slots;
> +			u64		saved_metric;
>  		};
>  		struct { /* software */
>  			struct hrtimer	hrtimer;

Normal counters save their counter value in hwc->period_left, why does
slots need a new word for that?

And since using METRIC means non-sampling, why can't we stick that
saved_metric field in one of the unused sampling fields?

ISTR asking this before...

  reply	other threads:[~2019-09-30 15:52 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-16 13:41 [PATCH V4 00/14] TopDown metrics support for Icelake kan.liang
2019-09-16 13:41 ` [PATCH V4 01/14] perf/x86/intel: Introduce the fourth fixed counter kan.liang
2019-09-16 13:41 ` [PATCH V4 02/14] perf/x86/intel: Set correct mask for TOPDOWN.SLOTS kan.liang
2019-09-16 13:41 ` [PATCH V4 03/14] perf/x86/intel: Move BTS index to 47 kan.liang
2019-09-16 13:41 ` [PATCH V4 04/14] perf/x86/intel: Basic support for metrics counters kan.liang
2019-09-16 13:41 ` [PATCH V4 05/14] perf/x86/intel: Fix the name of perf capabilities for perf METRICS kan.liang
2019-09-16 13:41 ` [PATCH V4 06/14] x86/math64: Provide a sane mul_u64_u32_div() implementation for x86_64 kan.liang
2019-09-16 13:41 ` [PATCH V4 07/14] perf/x86/intel: Support hardware TopDown metrics kan.liang
2019-09-30 13:06   ` Peter Zijlstra
2019-09-30 14:07     ` Peter Zijlstra
2019-09-30 14:53       ` Peter Zijlstra
2019-09-30 16:17         ` Liang, Kan
2019-09-30 16:21           ` Peter Zijlstra
2019-09-30 16:45             ` Liang, Kan
2019-09-30 18:18               ` Andi Kleen
2019-09-30 13:36   ` Peter Zijlstra
2019-09-16 13:41 ` [PATCH V4 08/14] perf/x86/intel: Support per thread RDPMC " kan.liang
2019-09-30 15:52   ` Peter Zijlstra [this message]
2019-09-30 18:18     ` Liang, Kan
2019-09-16 13:41 ` [PATCH V4 09/14] perf/x86/intel: Export TopDown events for Icelake kan.liang
2019-09-16 13:41 ` [PATCH V4 10/14] perf/x86/intel: Disable sampling read slots and topdown kan.liang
2019-09-16 13:41 ` [PATCH V4 11/14] perf/x86/intel: Name global status bit in NMI handler kan.liang
2019-09-16 13:41 ` [PATCH V4 12/14] perf/x86: Use event_base_rdpmc for RDPMC userspace support kan.liang
2019-09-16 13:41 ` [PATCH V4 13/14] perf, tools, stat: Support new per thread TopDown metrics kan.liang
2019-09-16 13:41 ` [PATCH V4 14/14] perf, tools: Add documentation for topdown metrics kan.liang
2019-09-30 12:48 ` [PATCH V4 00/14] TopDown metrics support for Icelake Liang, Kan

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=20190930155244.GP4553@hirez.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=acme@kernel.org \
    --cc=ak@linux.intel.com \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=eranian@google.com \
    --cc=jolsa@kernel.org \
    --cc=kan.liang@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --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).