Re: [PATCH] irqchip/gic-v3-its: cap lpi_id_bits to reduce memory footprint

[Marc Zyngier]

On Tue, 28 Aug 2018 05:53:26 +0100,
Jia He <hejianet@xxxxxxxxx> 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@xxxxxxxxxxxxxxxx>
> Suggested-by: Marc Zyngier <marc.zyngier@xxxxxxx>

Thanks for doing this. Small problem with this patch:

The email comes from hejianet@xxxxxxxxx, while the sign off is by
jia.he@xxxxxxxxxxxxxxxxx Your email should start with a:

	From: Jia He <jia.he@xxxxxxxxxxxxxxxx>

Other than that:

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

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

Thanks,

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

-- 
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