kernelnewbies.kernelnewbies.org archive mirror
 help / color / mirror / Atom feed
From: Jesse Simpson <jesse.simpson36@gmail.com>
To: "Valdis Klētnieks" <valdis.kletnieks@vt.edu>
Cc: Igor Pylypiv <igor.pylypiv@gmail.com>,
	kernelnewbies@kernelnewbies.org, "Tobin C. Harding" <me@tobin.cc>
Subject: Re: Where is PageHead defined in v5.0?
Date: Thu, 28 Mar 2019 16:49:29 -0400	[thread overview]
Message-ID: <20190328204929.GA6154@glitch> (raw)
In-Reply-To: <28865.1553752247@turing-police>

On Thu, Mar 28, 2019 at 01:50:47AM -0400, Valdis Klētnieks wrote:
> On Wed, 27 Mar 2019 17:23:05 -0700, Igor Pylypiv said:
> > and TESTPAGEFLAG defines PageHead:
> >         #define TESTPAGEFLAG(uname, lname, policy) \
> >         static __always_inline int Page##uname(struct page *page)
> >         (https://elixir.bootlin.com/linux/v5.0.5/source/include/linux/page-flags.h#L215)
> 
> General tip:  If you're trying to find where the kernel defines FooBar,
> and 'git grep FooBar' only finds uses and no definitions, it probably
> means somebody got over-exuberant with the ## pre-processor
> operator
> 
> 'git grep Foo##' usually reveals the culprit. ;)

Thanks for the tip Valdis. I'm going to look more into the ## operator so that
I can understand it's use case better. I've used macros before but this
one seems a bit strange.

:)

Jesse Simpson



_______________________________________________
Kernelnewbies mailing list
Kernelnewbies@kernelnewbies.org
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies

  reply	other threads:[~2019-03-28 20:51 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-27 22:26 Where is PageHead defined in v5.0? Tobin C. Harding
2019-03-28  0:34 ` Jesse Simpson
2019-03-27 23:49   ` Tobin C. Harding
2019-03-28  0:23     ` Igor Pylypiv
2019-03-28  4:43       ` Tobin C. Harding
2019-03-28  5:50       ` Valdis Klētnieks
2019-03-28 20:49         ` Jesse Simpson [this message]
2019-03-28 20:56         ` Tobin C. Harding

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=20190328204929.GA6154@glitch \
    --to=jesse.simpson36@gmail.com \
    --cc=igor.pylypiv@gmail.com \
    --cc=kernelnewbies@kernelnewbies.org \
    --cc=me@tobin.cc \
    --cc=valdis.kletnieks@vt.edu \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).