Re: [PATCH v4 0/4] arm64: SPE ACPI enablement

From: Hanjun Guo <guohanjun@huawei.com>
To: Jeremy Linton <jeremy.linton@arm.com>,
	<linux-arm-kernel@lists.infradead.org>
Cc: <linux-acpi@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<catalin.marinas@arm.com>, <will.deacon@arm.com>,
	<rjw@rjwysocki.net>, <lenb@kernel.org>, <mark.rutland@arm.com>,
	<lorenzo.pieralisi@arm.com>, <sudeep.holla@arm.com>
Subject: Re: [PATCH v4 0/4] arm64: SPE ACPI enablement
Date: Mon, 17 Jun 2019 16:36:32 +0800	[thread overview]
Message-ID: <7215e7f2-b8d3-999e-427b-428282765276@huawei.com> (raw)
In-Reply-To: <20190615010910.33921-1-jeremy.linton@arm.com>

On 2019/6/15 9:09, Jeremy Linton wrote:
> This patch series enables the Arm Statistical Profiling
> Extension (SPE) on ACPI platforms.
> 
> This is possible because ACPI 6.3 uses a previously
> reserved field in the MADT to store the SPE interrupt
> number, similarly to how the normal PMU is described.
> If a consistent valid interrupt exists across all the
> cores in the system, a platform device is registered.
> That then triggers the SPE module, which runs as normal.
> 
> We also add the ability to parse the PPTT for IDENTICAL
> cores. We then use this to sanity check the single SPE
> device we create. This creates a bit of a problem with
> respect to the specification though. The specification
> says that its legal for multiple tree's to exist in the
> PPTT. We handle this fine, but what happens in the
> case of multiple tree's is that the lack of a common
> node with IDENTICAL set forces us to assume that there
> are multiple non-IDENTICAL cores in the machine.
> 
> v3->v4: Rebase to 5.2.
> 	Minor formatting, patch rearrangement.
> 	Add missing `inline` in static header definition.
> 	Drop ARM_SPE_ACPI and just use ARM_SPE_PMU.

Tested on top of 5.2-rc1, I can see in the boot log:

arm_spe_pmu arm,spe-v1: probed for CPUs 0-95 [max_record_sz 128, align 4, features 0x7]

and I also tested perf record, and works as expected,

Tested-by: Hanjun Guo <guohanjun@huawei.com>

Thanks
Hanjun