From: Borislav Petkov <bp@alien8.de>
To: Jarkko Sakkinen <jarkko@kernel.org>
Cc: linux-sgx@vger.kernel.org,
Dave Hansen <dave.hansen@linux.intel.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] x86/sgx: Do not update sgx_nr_free_pages in sgx_setup_epc_section()
Date: Wed, 7 Apr 2021 18:18:11 +0200 [thread overview]
Message-ID: <20210407161811.GK25319@zn.tnic> (raw)
In-Reply-To: <YG3X454GI4U2BZVU@kernel.org>
On Wed, Apr 07, 2021 at 07:03:47PM +0300, Jarkko Sakkinen wrote:
> > Which leads to my question: what is sgx_nr_free_pages supposed to denote?
> >
> > Because I understand the callpath
> >
> > sgx_page_cache_init
> > ...
> > for (i = 0; i < ARRAY_SIZE(sgx_epc_sections); i++) {
> > ...
> > sgx_setup_epc_section
> > ...
> > sgx_nr_free_pages += nr_pages;
> >
> > as adding the number of pages of each new EPC section to the total
> > number of the free pages. Unless that variable accounts something else.
> >
> > So what does this variable actually mean?
>
> It's used for only to trigger watermark for reclaiming. I.e. causes
> ksgxd to trigger. And it gives the number of total free EPC pages in
> all NUMA nodes.
So the callpath I laid out above is adding the number of pages of each
section to the total free EPC pages number.
Why is that wrong and why is your patch needed?
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
next prev parent reply other threads:[~2021-04-07 16:18 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-05 23:26 [PATCH v2 1/2] x86/sgx: Do not update sgx_nr_free_pages in sgx_setup_epc_section() Jarkko Sakkinen
2021-04-05 23:26 ` [PATCH v2 2/2] x86/sgx: Add sgx_nr_{all, free}_pages to the debugfs Jarkko Sakkinen
2021-04-07 15:56 ` Borislav Petkov
2021-04-07 16:09 ` Jarkko Sakkinen
2021-04-07 16:15 ` Borislav Petkov
2021-04-08 8:52 ` Jarkko Sakkinen
2021-04-08 9:01 ` Borislav Petkov
2021-04-08 9:13 ` Jarkko Sakkinen
2021-04-08 9:32 ` Borislav Petkov
2021-04-08 16:27 ` Jarkko Sakkinen
2021-04-07 15:49 ` [PATCH v2 1/2] x86/sgx: Do not update sgx_nr_free_pages in sgx_setup_epc_section() Borislav Petkov
2021-04-07 16:03 ` Jarkko Sakkinen
2021-04-07 16:18 ` Borislav Petkov [this message]
2021-04-08 8:48 ` Jarkko Sakkinen
2021-04-08 8:56 ` Borislav Petkov
2021-04-08 9:22 ` Jarkko Sakkinen
2021-04-08 9:29 ` Borislav Petkov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210407161811.GK25319@zn.tnic \
--to=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=jarkko@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sgx@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.