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Date:   Tue, 9 Nov 2021 11:58:40 +0100
From:   "hch@lst.de" <hch@lst.de>
To:     "Wang, Zhi A" <zhi.a.wang@intel.com>
Cc:     "hch@lst.de" <hch@lst.de>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Zhi Wang <zhi.wang.linux@gmail.com>,
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Subject: Re: [PATCH 1/3] i915/gvt: seperate tracked MMIO table from
 handlers.c
Message-ID: <20211109105840.GA9675@lst.de>
References: <20211108212718.10576-1-zhi.a.wang@intel.com> <875yt17qzs.fsf@intel.com> <5dd106e7-e62f-dfcd-bfa1-3f92794b8e3e@intel.com> <87o86t636f.fsf@intel.com> <20211109103622.GA7607@lst.de> <ddff22c4-fa19-24b4-c5e5-9910abb02bf6@intel.com>
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On Tue, Nov 09, 2021 at 10:51:27AM +0000, Wang, Zhi A wrote:
> Can you elaborate more about this? We need the hash query from the table 
> ASAP when the hypervisor trapped a mmio access. It's a critical path and 
> we tried different data structure in the kernel and the hash table gives 
> the best performance.

Ok, I misunderstood the hashtable.h interface.  hash_for_each_possible
actually does a hash lookup instead of an interation despite the rather
misleading name.