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Message-ID: <a2d1c44d-6450-4641-843e-8981bdb4d533@linux.intel.com>
Date: Wed, 24 Apr 2024 11:43:30 +0800
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Cc: baolu.lu@linux.intel.com, linux-kernel@vger.kernel.org,
 Steve Wahl <steve.wahl@hpe.com>, Russ Anderson <russ.anderson@hpe.com>
Subject: Re: [PATCH v2] iommu/vt-d: Allocate DMAR fault interrupts locally
To: Dimitri Sivanich <sivanich@hpe.com>, Thomas Gleixner
 <tglx@linutronix.de>, Joerg Roedel <joro@8bytes.org>,
 Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
 Will Deacon <will@kernel.org>, Robin Murphy <robin.murphy@arm.com>,
 David Woodhouse <dwmw2@infradead.org>, Mark Rutland <mark.rutland@arm.com>,
 Peter Zijlstra <peterz@infradead.org>, Arnd Bergmann <arnd@arndb.de>,
 YueHaibing <yuehaibing@huawei.com>, iommu@lists.linux.dev
References: <Zfydpp2Hm+as16TY@hpe.com>
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From: Baolu Lu <baolu.lu@linux.intel.com>
In-Reply-To: <Zfydpp2Hm+as16TY@hpe.com>
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On 3/22/24 4:50 AM, Dimitri Sivanich wrote:
> The Intel IOMMU code currently tries to allocate all DMAR fault interrupt
> vectors on the boot cpu.  On large systems with high DMAR counts this
> results in vector exhaustion, and most of the vectors are not initially
> allocated socket local.
> 
> Instead, have a cpu on each node do the vector allocation for the DMARs on
> that node.  The boot cpu still does the allocation for its node during its
> boot sequence.
> 
> Signed-off-by: Dimitri Sivanich<sivanich@hpe.com>
> ---
> 
> v2: per Thomas Gleixner, implement this from a DYN CPU hotplug state, though
>      this implementation runs in CPUHP_AP_ONLINE_DYN space rather than
>      CPUHP_BP_PREPARE_DYN space.

Patch has been queued for iommu/vt-d.

Best regards,
baolu