From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Wed, 12 May 2010 21:13:56 +0100 Subject: asmlinkage In-Reply-To: References: Message-ID: <20100512201356.GA5611@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, May 10, 2010 at 12:49:24AM +0300, Alexander (Sasha) Sirotkin wrote: > Sorry for yet another basic question, but why "asmlinkage" is an empty macro > on ARM? ARM doesn't require any special API modification to call functions from assembly. x86 has two different calling conventions - one is to stack all function arguments, the other passes some arguments via registers. asmlinkage selects between them. However, we keep the asmlinkage labelling on ARM because it's useful to indicate which functions are called by assembly - and therefore which need closer inspection when their signature is changed to make sure the assembly calling them is also fixed.