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Date:   Mon, 17 Apr 2023 08:40:42 -0700
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Subject: Rename restrictedmem => guardedmem? (was: Re: [PATCH v10 0/9] KVM:
 mm: fd-based approach for supporting KVM)
From:   Sean Christopherson <seanjc@google.com>
To:     Chao Peng <chao.p.peng@linux.intel.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        "Maciej S . Szmigiero" <mail@maciej.szmigiero.name>,
        Vlastimil Babka <vbabka@suse.cz>,
        Vishal Annapurve <vannapurve@google.com>,
        Yu Zhang <yu.c.zhang@linux.intel.com>,
        Chao Peng <chao.p.peng@linux.intel.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
        dhildenb@redhat.com, Quentin Perret <qperret@google.com>,
        tabba@google.com, Michael Roth <michael.roth@amd.com>,
        wei.w.wang@intel.com, Mike Rapoport <rppt@kernel.org>,
        Liam Merwick <liam.merwick@oracle.com>,
        Isaku Yamahata <isaku.yamahata@gmail.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        Ackerley Tng <ackerleytng@google.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
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What do y'all think about renaming "restrictedmem" to "guardedmem"?

I want to start referring to the code/patches by its syscall/implementation name
instead of "UPM", as "UPM" is (a) very KVM centric, (b) refers to the broader effort
and not just the non-KVM code, and (c) will likely be confusing for future reviewers
since there's nothing in the code that mentions "UPM" in any way.

But typing out restrictedmem is quite tedious, and git grep shows that "rmem" is
already used to refer to "reserved memory".

Renaming the syscall to "guardedmem"...

  1. Allows for a shorthand and namespace, "gmem", that isn't already in use by
     the kernel (see "reserved memory above").
 
  2. Provides a stronger hint as to its purpose.  "Restricted" conveys that the
     allocated memory is limited in some way, but doesn't capture how the memory
     is restricted, e.g. "restricted" could just as easily mean that the allocation
     can be restricted to certain types of backing stores or something.  "Guarded"
     on the other hand captures that the memory has extra defenses of some form.

  3. Is shorter to type and speak.  Work smart, not hard :-)

  4. Isn't totally wrong for the KVM use case if someone assumes the "g" means
     "guest" when reading mail and whatnot.


P.S. I trimmed the Cc/To substantially for this particular discussion to avoid
     spamming folks that don't (yet) care about this stuff with another potentially
     lengthy thread.  Feel free to add (back) any people/lists.