From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <9ab217670704151043j1da7acc2j61869c6d54f736f7@mail.gmail.com> Date: Sun, 15 Apr 2007 13:43:14 -0400 From: "Devon H. O'Dell" To: "Fans of the OS Plan 9 from Bell Labs" <9fans@cse.psu.edu> Subject: Re: [9fans] Re: [sources] 20070413: /rc/bin/cpurc.local In-Reply-To: <9ab217670704151026k6de961c0q1ecd0385c95772c7@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <5d375e920704150106m5865747flb6ae25392f8744ca@mail.gmail.com> <9ab217670704151026k6de961c0q1ecd0385c95772c7@mail.gmail.com> Topicbox-Message-UUID: 48fd9e18-ead2-11e9-9d60-3106f5b1d025 2007/4/15, Devon H. O'Dell : > p->mach is a pointer back to a machine structure. I'm assuming this > only gets set when a process is being run. I suppose this test is here > in case another CPU took over running the process. Though, this can't be the case, because m->readied isn't locked when we come in here, and if we're running MP, wouldn't it be possible (though unlikely) that another CPU takes the process between the assignment and the test? Especially if running heavily threaded applications on MP systems? > --dho