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Date:   Wed, 11 Oct 2023 16:14:52 +0300
From:   "kirill.shutemov@linux.intel.com" <kirill.shutemov@linux.intel.com>
To:     "Huang, Kai" <kai.huang@intel.com>
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        "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>,
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        "Nakajima, Jun" <jun.nakajima@intel.com>,
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        "sathyanarayanan.kuppuswamy@linux.intel.com" 
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Subject: Re: [PATCH 09/13] x86/tdx: Account shared memory
Message-ID: <20231011131452.r42nemcajjcj77hq@box.shutemov.name>
References: <20231005131402.14611-1-kirill.shutemov@linux.intel.com>
 <20231005131402.14611-10-kirill.shutemov@linux.intel.com>
 <f3776d2b6d45e74b4d0e62eb4e788c578132c21c.camel@intel.com>
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On Tue, Oct 10, 2023 at 10:05:21AM +0000, Huang, Kai wrote:
> 
> > +#ifdef CONFIG_DEBUG_FS
> > +static int tdx_shared_memory_show(struct seq_file *m, void *p)
> > +{
> > +	unsigned long addr, end;
> > +	unsigned long found = 0;
> > +
> > +	addr = PAGE_OFFSET;
> > +	end  = PAGE_OFFSET + get_max_mapped();
> > +
> > +	while (addr < end) {
> > +		unsigned long size;
> > +		unsigned int level;
> > +		pte_t *pte;
> > +
> > +		pte = lookup_address(addr, &level);
> > +		size = page_level_size(level);
> > +
> > +		if (pte && pte_decrypted(*pte))
> > +			found += size / PAGE_SIZE;
> > +
> > +		addr += size;
> 
> This could be a long loop, perhaps add cond_resched() here?

Sure.

-- 
  Kiryl Shutsemau / Kirill A. Shutemov