linux-kernel - Re: [Patch v4 09/13] perf/x86/intel: Setup PEBS data configuration and enable legacy groups

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Message-ID: <20250621094343.GY1613376@noisy.programming.kicks-ass.net>
Date: Sat, 21 Jun 2025 11:43:43 +0200
From: Peter Zijlstra <peterz@...radead.org>
To: Dapeng Mi <dapeng1.mi@...ux.intel.com>
Cc: Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Namhyung Kim <namhyung@...nel.org>, Ian Rogers <irogers@...gle.com>,
	Adrian Hunter <adrian.hunter@...el.com>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
	Kan Liang <kan.liang@...ux.intel.com>,
	Andi Kleen <ak@...ux.intel.com>,
	Eranian Stephane <eranian@...gle.com>, linux-kernel@...r.kernel.org,
	linux-perf-users@...r.kernel.org, Dapeng Mi <dapeng1.mi@...el.com>
Subject: Re: [Patch v4 09/13] perf/x86/intel: Setup PEBS data configuration
 and enable legacy groups

On Fri, Jun 20, 2025 at 10:39:05AM +0000, Dapeng Mi wrote:

> +		if (cpuc->n_pebs == cpuc->n_large_pebs)
> +			index.split.thresh = ARCH_PEBS_THRESH_MUL;
> +		else
> +			index.split.thresh = ARCH_PEBS_THRESH_SINGLE;

> +	if (cpuc->n_pebs == cpuc->n_large_pebs)
> +		index.split.thresh = ARCH_PEBS_THRESH_MUL;
> +	else
> +		index.split.thresh = ARCH_PEBS_THRESH_SINGLE;

> +/*
> + * The largest PEBS record could consume a page, ensure
> + * a record at least can be written after triggering PMI.
> + */
> +#define ARCH_PEBS_THRESH_MUL	((PEBS_BUFFER_SIZE - PAGE_SIZE) >> PEBS_BUFFER_SHIFT)
> +#define ARCH_PEBS_THRESH_SINGLE	1

Can we please do something like s/MUL/MULTI/ or so. My brain keeps
trying to make it MULtiply and that doesn't really work.