Date: Thu, 4 Dec 2008 07:24:41 -0800 From: "Maksim Yevmenkin" <maksim.yevmenkin@gmail.com> To: "Garrett Cooper" <yanefbsd@gmail.com> Cc: "current@freebsd.org" <current@freebsd.org> Subject: Re: RFC: small syscons and kbd patch Message-ID: <bb4a86c70812040724w43ddec15yab72920d80d879d3@mail.gmail.com> In-Reply-To: <7d6fde3d0812040324y3bf0901cy1f4a6d961362c314@mail.gmail.com> References: <bb4a86c70812021701i621fdcfjb6a58a7f5cf781d5@mail.gmail.com> <7d6fde3d0812040324y3bf0901cy1f4a6d961362c314@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Dec 4, 2008 at 3:24 AM, Garrett Cooper <yanefbsd@gmail.com> wrote: > On Tue, Dec 2, 2008 at 5:01 PM, Maksim Yevmenkin > <maksim.yevmenkin@gmail.com> wrote: >> Dear Hackers, >> >> can someone please review the attached small patch for syscons and >> kbd? it should be a no-op mostly. the patch basically does >> >> 1) removes bogus layering in syscons, i.e. basically removes sccngetch(); >> 2) implements advisory lock for kbd (based on atomic(9)); >> 3) implements new POLLED flag for kbd; >> >> this is a part of a plan to fix keyboard access races in syscons. >> >> thanks, >> max > > Max, > Why are you double and triple negating on this line? > > + return (atomic_cmpset_acq_int(&kbd->kb_locked, !!!on, !!on)); the idea was to ensure that kbd->kb_locked variable only takes values 0 (zero) and 1 (one). thanks, max
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bb4a86c70812040724w43ddec15yab72920d80d879d3>