From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann E. MORIN Date: Sun, 17 Aug 2014 16:20:00 +0200 Subject: [Buildroot] [PATCH 07/24 v4] manual: document dependencies on atomic operations In-Reply-To: <38612d6b-068a-4a68-8f97-a595df32e458@email.android.com> References: <4061c3ce3e322eed4f6a91e635133d0e0dd2e2f4.1408279142.git.yann.morin.1998@free.fr> <5dc49087-92a9-4ec1-a145-bcc77ecbad46@email.android.com> <20140817131527.GE5274@free.fr> <38612d6b-068a-4a68-8f97-a595df32e458@email.android.com> Message-ID: <20140817142000.GH5274@free.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Thomas, All, On 2014-08-17 15:25 +0200, Thomas De Schampheleire spake thusly: > "Yann E. MORIN" schreef: > >Thomas, All, > > > >On 2014-08-17 15:01 +0200, Thomas De Schampheleire spake thusly: > >> "Yann E. MORIN" schreef: > >> >From: Anton Kolesov > >> > > >> >Add atomic operations to the list of generic dependencies. > >> > > >> >Since this is an architecture option, there is no comment string to be > >> >added. > >> > > >> >Signed-off-by: Anton Kolesov > >> >[yann.morin.1998 at free.fr: use the new arch-option; remove comment string] > >> >Signed-off-by: "Yann E. MORIN" > >> >--- > >> > docs/manual/adding-packages-directory.txt | 4 ++++ > >> > 1 file changed, 4 insertions(+) > >> > > >> >diff --git a/docs/manual/adding-packages-directory.txt b/docs/manual/adding-packages-directory.txt > >> >index 93e6a3e..40a81d5 100644 > >> >--- a/docs/manual/adding-packages-directory.txt > >> >+++ b/docs/manual/adding-packages-directory.txt > >> >@@ -219,6 +219,10 @@ use in the comment. > >> > ** Dependency symbol: +BR2_USE_MMU+ > >> > ** Comment string: no comment to be added > >> > > >> >+* Atomic operations > >> >+** Dependency symbol: +BR2_ARCH_HAS_ATOMICS+ > >> >+** Comment string: no comment to be added > >> >+ > >> > >> Should we provide a brief explanation, reference, or > >> name of these functions to make it a bit clearer what > >> is meant with 'atomic operations'? > > > >Well, the atomics are all named differently in different architectures. > > > >For example, armv6+ has LDREX and STREX (amon others): > > http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dht0008a/ch01s02s01.html > > > >While on x86, I don't think there are corresponding instructions, but > >you can prefix some intructions with the LOCK prefix to achieve a > >similar result. > > > >So, I would not know what to put in here. Also, we do not explain what > >the other options are (like MMU, for example). Why would we do that for > >this specific option, and not others? > > Because MMU is a widely known acronym for anyone in the embedded world, > but 'atomics' or 'atomic operations' is a much more general term that > is less obvious, IMHO. Weird how different people, even from the same field, would consider one thing as a fundamentals and not some other thing, or the opposite. :-) > Maybe the description can clarify that we're talking about a dependency > on _CPU_ atomic _instructions_? OK, let's strike a deal: I keep the option name as-is (I like it), but I add a bit of explanations in the manual. Deal? ;-) Regards, Yann E. MORIN. -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | +33 223 225 172 `------------.-------: X AGAINST | \e/ There is no | | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. | '------------------------------^-------^------------------^--------------------'