From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Luck, Tony" Date: Thu, 10 Jan 2002 23:26:58 +0000 Subject: RE: [Linux-ia64] [PATCH] Support for alternative kernel profiler Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org We don't currently have any way for different software packages to share the performance counters, so it's very likely that there would be interactions with Stephane's PMU code (e.g. I rewrite cr.pmv to a new vector and re-write all of the pmc[] and pmd[] registers for my own purposes ... this will upset Stephane's code, similarly my code does not expect anyone else to touch any PMU registers, or fiddle with psr.pp/dcr.pp). It would probably be safest to turn off CONFIG_PERFMON in a kernel that is going to load an alternate profiler ... my profiler seems to cope ok provided nobody calls sys_perfmonctl(). -Tony David Mosberger wrote: > I'd like Stephane to take a look at this patch and see whether there > are any potential bad interactions with the PMU code he is working on > (due to the manipulation of the psr.pp bit). Other than that, the > patch looks good to me.