From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Date: Wed, 17 Jun 2015 02:27:07 +0000 Subject: Re: [RFC PATCH] perf/kvm: Guest Symbol Resolution for powerpc Message-Id: <5580DAFB.4080304@gmail.com> List-Id: References: <1434423053-2173-1-git-send-email-hemant@linux.vnet.ibm.com> <55803883.50504@gmail.com> <5580CC69.2090200@linux.vnet.ibm.com> In-Reply-To: <5580CC69.2090200@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Hemant Kumar , linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org, kvm-ppc@vger.kernel.org, acme@kernel.org, mingo@kernel.org, sukadev@linux.vnet.ibm.com, maddy@linux.vnet.ibm.com, srikar@linux.vnet.ibm.com, paulus@samba.org, namhyung@kernel.org, jolsa@kernel.org, peterz@infradead.org On 6/16/15 7:24 PM, Hemant Kumar wrote: > Because, this depends on the kernel tracepoint "kvm_hv:kvm_guest_exit". > perf_prepare_sample() in the kernel side sets the event->header.misc > field to > PERF_RECORD_MISC_KERNEL through perf_misc_flags(pt_regs). In case of > tracepoints which always get hit in the host kernel context, the > perf_misc_flags() will always return PERF_RECORD_MISC_KERNEL. > > IMHO we will rather have to set the cpumode in the user space for this > tracepoint > and we can't depend on the event->header.misc field for this case. > > What would you suggest? > oh, right you are using a tracepoint for this. It does not have the hooks to specify cpumode. Never mind.