From mboxrd@z Thu Jan 1 00:00:00 1970 From: mingo@kernel.org (Ingo Molnar) Date: Sat, 19 Sep 2015 12:09:34 +0200 Subject: [RFC PATCH 20/20] coresight: updating documentation to reflect integration with perf In-Reply-To: <1442593594-10665-21-git-send-email-mathieu.poirier@linaro.org> References: <1442593594-10665-1-git-send-email-mathieu.poirier@linaro.org> <1442593594-10665-21-git-send-email-mathieu.poirier@linaro.org> Message-ID: <20150919100934.GA31274@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Looks like a pretty useful feature all around. While reading the description I noticed a few typos: * Mathieu Poirier wrote: > +Regardless of the amnout ETM/PTM IP block in a system (usually equal to the > +amount of processor core), the "cs_etm" PMU will be listed only once. s/amnout/amount > +Tracing limited to user and kernel space can also be used to narrow the amount > +of collected tracers: s/tracers/traces > +The Coresight PMUs can be configured to work in "full trace" or "snapshot" mode. > +In full trace mode trade acquisition is enable from beginning to end with trace > +data being recorded continuously: s/trade acquisition/trace acquisition s/is enable from/is enabled from > +Since this can lead to a significant amount of data and that some device are > +limited in disk space snapshot mode can be used instead. s/and that some device are limited in disk space/ and because some devices are limited in disk space > +Trace data collected during trace runs end up in the centennial "perf.data" > +file. hey, perf isn't 100 years old! :-) s/centennial/central ? Also, 'data' is singular in this context, so I think: s/data collected during trace runs end up in the /data collected during trace runs ends up in the > [...] Trace configuration information necessary for trace decoding are also > +embedded in the "perf.data" file. s/are/is > Two new headers, 'PERF_RECORD_AUXTRACE_INFO' > +and 'PERF_RECORD_AUXTRACE' have been added to list of event types in order to > +find out where the different sections start. s/to list of event types /to the list of event types > + > +It is worth nothing that a set of metadata information exists for each tracer > +that participated in a trace run. [...] s/nothing /noting As such if 5 processors have been engaged, > +5 set of metadata will be found in the perf.data file. s/5 set of metadata /5 sets of metadata > +Metadata information is collected directly from the ETM/PTM management registers > +using the sysFS interface. Since there is not way for the perf command line > +tool to associate a CPU with a tracer, a symbolic link has been created between > +the cs_etm sysFS event directory and each Coresight tracer: s/there is not way /there is no way > +As with the perf method described above, a coresight sink needs to be identify > +before trace collection can commence. Btw., 'Coresight' is spelled in two different ways throughout this document: capitalized and non-capitalized. Please pick one variant and use it consistently. > any given moment. As a generic operation, all device pertaining to the sink > -class will have an "active" entry in sysfs: s/all device pertaining to /all devices pertaining to Thanks, Ingo