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;
Date:   Wed, 31 Jan 2018 14:15:05 +0100
From:   Jiri Olsa <jolsa@redhat.com>
To:     Andi Kleen <ak@linux.intel.com>
Cc:     Stephane Eranian <eranian@google.com>,
        "Liang, Kan" <kan.liang@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH V3 0/5] bugs fix for large PEBS mmap read and rdpmc read
Message-ID: <20180131131505.GB31614@krava>
References: <20180130133917.GC29098@krava>
 <6d708c09-52a7-a906-b651-b133a7b4f189@linux.intel.com>
 <20180130150454.GE29098@krava>
 <35090c62-466a-aec8-b1a3-69def959c1c6@linux.intel.com>
 <CABPqkBRWtSsKEM7ycPs0HYSKLsYDmZhr4ztUmMMqsytYamPGsw@mail.gmail.com>
 <24210bcb-0e4b-58fe-bcda-da30019f6e7e@linux.intel.com>
 <20180130185212.GA16806@krava>
 <CABPqkBRp9bDmGECStbAHA5Ja0SjJmDQ2SOceat=qXno707MuAA@mail.gmail.com>
 <20180131035941.GW26209@tassilo.jf.intel.com>
 <20180131091539.GA3313@krava>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20180131091539.GA3313@krava>
User-Agent: Mutt/1.9.1 (2017-09-22)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, Jan 31, 2018 at 10:15:39AM +0100, Jiri Olsa wrote:
> On Tue, Jan 30, 2018 at 07:59:41PM -0800, Andi Kleen wrote:
> > > Still, the part I am missing here, is why asking for
> > > PERF_SAMPLE_PERIOD voids large PEBS.
> > 
> > I think it was disabled together with frequency mode
> > (which we could support too, but it's a bit more work)
> > 
> > But yes PERIOD could probably be allowed.
> 
> looks like it's just a matter of adding PERF_SAMPLE_PERIOD
> into PEBS_FREERUNNING_FLAGS, we already populate period
> in setup_pebs_sample_data
> 
> jirka
> 
> 
> ---
> diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
> index 8e4ea143ed96..78f91ec1056e 100644
> --- a/arch/x86/events/perf_event.h
> +++ b/arch/x86/events/perf_event.h
> @@ -93,7 +93,8 @@ struct amd_nb {
>  	PERF_SAMPLE_ID | PERF_SAMPLE_CPU | PERF_SAMPLE_STREAM_ID | \
>  	PERF_SAMPLE_DATA_SRC | PERF_SAMPLE_IDENTIFIER | \
>  	PERF_SAMPLE_TRANSACTION | PERF_SAMPLE_PHYS_ADDR | \
> -	PERF_SAMPLE_REGS_INTR | PERF_SAMPLE_REGS_USER)
> +	PERF_SAMPLE_REGS_INTR | PERF_SAMPLE_REGS_USER | \
> +	PERF_SAMPLE_PERIOD)

seems to work, getting large PEBS event for following command line:

  perf record -e cycles:P -c 100 --no-timestamp -C 0 --period


jirka