From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.mail.elte.hu ([157.181.151.9]:40425 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752407AbZBVROD (ORCPT ); Sun, 22 Feb 2009 12:14:03 -0500 Date: Sun, 22 Feb 2009 18:13:44 +0100 From: Ingo Molnar Subject: Re: [PATCH] tracing/markers: make markers select tracepoints Message-ID: <20090222171344.GC6570@elte.hu> References: <499edf47.1818d00a.060b.2b8d@mx.google.com> <499EE162.4050008@oracle.com> <20090220172241.GF24538@elte.hu> <20090220173107.GH5732@nowhere> <20090220174811.GL24538@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kbuild-owner@vger.kernel.org List-ID: To: "Frank Ch. Eigler" Cc: Frederic Weisbecker , Avi Kivity , Randy Dunlap , Steven Rostedt , linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org * Frank Ch. Eigler wrote: > Ingo Molnar writes: > > > [...] > > there's i think the KVM usecase where markers are used > > essentially a printk()-alike flexible tracing facility. > > > > [...] > > ./vmx.c: KVMTRACE_3D(MSR_READ, vcpu, ecx, (u32)data, (u32)(data >> 32), > > ./vmx.c: KVMTRACE_3D(MSR_WRITE, vcpu, ecx, (u32)data, (u32)(data >> 32), > > ./vmx.c: KVMTRACE_0D(PEND_INTR, vcpu, handler); > > > > I think this could easily be converted to a wrapper around > > ftrace_printk() plus a "kvmtrace" ftrace plugin [...] > > It would be even easier converted to the markers API directly, > without the KVMTRACE* macro intermediary: > > before: > KVMTRACE_3D(MSR_READ, &svm->vcpu, ecx, (u32)data, > (u32)(data >> 32), handler); > after: > trace_mark(kvmtrace, "MSR_READ: %p, %08lx, %016Lx\n", > &svm->vcpu, ecx, data); > > All this already "just works". except that we are removing markers. Ingo