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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Fri, 11 Jan 2019 13:10:47 -0800
Message-ID: <CAHk-=whQJ-gj2M4ZJj8LnZXBK9k3fiRVjAXD9+M5D2Ja+N2mug@mail.gmail.com>
Subject: Re: [PATCH v3 0/6] Static calls
To:     Andy Lutomirski <luto@kernel.org>
Cc:     Josh Poimboeuf <jpoimboe@redhat.com>,
        Nadav Amit <namit@vmware.com>,
        Peter Zijlstra <peterz@infradead.org>,
        "the arch/x86 maintainers" <x86@kernel.org>,
        Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Jason Baron <jbaron@akamai.com>, Jiri Kosina <jkosina@suse.cz>,
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        Julia Cartwright <julia@ni.com>, Jessica Yu <jeyu@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
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        Edward Cree <ecree@solarflare.com>,
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On Fri, Jan 11, 2019 at 1:05 PM Andy Lutomirski <luto@kernel.org> wrote:
>
> > Yeah, my suggestion doesn't allow for batching, since it would
> > basically generate one trampoline for every rewritten instruction.
>
> Sure it does.  Just make 1000 trampolines and patch 1000 sites in a
> batch :)  As long as the number of trampolines is smallish (e.g. fits
> in a page), then we should be in good shape.

Yeah, I guess that's true.

But let's not worry about it. I don't think we do batching for any
alternative instruction rewriting right now, do we?

             Linus