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Date:   Tue, 28 Aug 2018 09:58:02 +0100
Message-ID: <865zzuyijp.wl-marc.zyngier@arm.com>
From:   Marc Zyngier <marc.zyngier@arm.com>
To:     Jia He <hejianet@gmail.com>, Thomas Gleixner <tglx@linutronix.de>
Cc:     Jason Cooper <jason@lakedaemon.net>, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Jia He <jia.he@hxt-semitech.com>
Subject: Re: [PATCH] irqchip/gic-v3-its: cap lpi_id_bits to reduce memory footprint
In-Reply-To: <1535432006-2304-1-git-send-email-jia.he@hxt-semitech.com>
References: <1535432006-2304-1-git-send-email-jia.he@hxt-semitech.com>
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On Tue, 28 Aug 2018 05:53:26 +0100,
Jia He <hejianet@gmail.com> wrote:
> 
> In commit fe8e93504ce8 ("irqchip/gic-v3-its: Use full range of LPIs"),
> it removes the cap for lpi_id_bits. But it will cause more pointless
> memory footprint.
> 
> There is a WARN_ON when my QDF2400 server boots up (pagesize is 4k)
> ============begin===============

[trimming not-so-useful trace]

> ============end============
> 
> In its_alloc_lpi_tables, lpi_id_bits is 24 in QDF2400. Then
> its_allocate_prop_table will try to allocate 16M(order 12 if
> pagesize=4k). Thus it causes the WARN_ON.
> 
> As said by Marc,
> Capping lpi_id_bits at 16 (which is what we had before) is plenty,
> will save a some memory, and gives some margin before we need to push
> it up again.
> 
> This patch re-caps the lpi_id_bits.
> 
> Fixes: fe8e93504ce8 ("irqchip/gic-v3-its: Use full range of LPIs")
> Signed-off-by: Jia He <jia.he@hxt-semitech.com>
> Suggested-by: Marc Zyngier <marc.zyngier@arm.com>

Thanks for doing this. Small problem with this patch:

The email comes from hejianet@gmail.com, while the sign off is by
jia.he@hxt-semitech.com. Your email should start with a:

	From: Jia He <jia.he@hxt-semitech.com>

Other than that:

Acked-by: Marc Zyngier <marc.zyngier@arm.com>

Thomas, would you mind picking this up so that it gets into the next
convenient -rc?

Thanks,

	M. (/me goes back hiking...)
	

-- 
Jazz is not dead, it just smell funny.