linux-kernel - Re: [PATCH v9 10/15] x86/sgx: Add EPC reclamation in cgroup try

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Message-ID: <c913193c0560c4372d2fdb31e9edb28bcb419f50.camel@intel.com>
Date: Fri, 23 Feb 2024 10:18:18 +0000
From: "Huang, Kai" <kai.huang@...el.com>
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Subject: Re: [PATCH v9 10/15] x86/sgx: Add EPC reclamation in cgroup
 try_charge()

> > 
> Right. When code reaches to here, we already passed reclaim per cgroup.  

Yes if try_charge() failed we must do pre-cgroup reclaim.

> The cgroup may not at or reach limit but system has run out of physical  
> EPC.
> 

But after try_charge() we can still choose to reclaim from the current group,
but not necessarily have to be global, right?  I am not sure whether I am
missing something, but could you elaborate why we should choose to reclaim from
the global?