BMC/Intel-BMC/linux.git/tools/perf/util/vdso.c, branch master

perf tools: Include errno.h where needed

2017-04-19T16:01:51+00:00

Removing it from util.h, part of an effort to disentangle the includes hell, that makes changes to util.h or something included by it to cause a complete rebuild of the tools. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-ztrjy52q1rqcchuy3rubfgt2@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Find right DSO taking into account if binary is 32 or 64-bit

2016-06-23T13:25:58+00:00

There's a problem in machine__findnew_vdso(), vdso buildid generated by a 32-bit machine stores it with the name 'vdso', but when processing buildid on a 64-bit machine with the same 'perf.data', perf will search for vdso named as 'vdso32' and get failed. This patch tries to find the existing dsos in machine->dsos by thread dso_type. 64-bit thread tries to find vdso with name 'vdso', because all 64-bit vdso is named as that. 32-bit thread first tries to find vdso with name 'vdso32' if this thread was run on 64-bit machine, if failed, then it tries 'vdso' which indicates that the thread was run on 32-bit machine when recording. Committer note: Additional explanation by Adrian Hunter: We match maps to builds ids using the file name - consider machine__findnew_[v]dso() called in map__new(). So in the context of a perf data file, we consider the file name to be unique. A vdso map does not have a file name - all we know is that it is vdso. We look at the thread to tell if it is 32-bit, 64-bit or x32. Then we need to get the build id which has been recorded using short name "[vdso]" or "[vdso32]" or "[vdsox32]". The problem is that on a 32-bit machine, we use the name "[vdso]". If you take a 32-bit perf data file to a 64-bit machine, it gets hard to figure out if "[vdso]" is 32-bit or 64-bit. This patch solves that problem. ---- This also merges a followup patch fixing a problem introduced by the original submission of this patch, that would crash 'perf record' when recording samples for a 32-bit app on a 64-bit system. Signed-off-by: He Kuang Acked-by: Adrian Hunter Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Andi Kleen Cc: David Ahern Cc: Ekaterina Tumanova Cc: Jiri Olsa Cc: Josh Poimboeuf Cc: Kan Liang Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Pekka Enberg Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Sukadev Bhattiprolu Cc: Wang Nan Link: http://lkml.kernel.org/r/1463475894-163531-1-git-send-email-hekuang@huawei.com Link: http://lkml.kernel.org/r/1466578626-92406-6-git-send-email-hekuang@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix lockup using 32-bit compat vdso

2015-07-07T14:05:08+00:00

The __machine__findnew_compat() function is called only from __machine__findnew_vdso_compat() which is called only from machine__findnew_vdso() which already holds machine->dsos.lock, so remove locking from __machine__findnew_compat(). This manifests itself tracing 32-bit programs with a 64-bit perf. Signed-off-by: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/1436267618-20521-1-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Reference count struct dso

2015-06-08T13:31:40+00:00

This has a different model than the 'thread' and 'map' struct lifetimes: there is not a definitive "don't use this DSO anymore" event, i.e. we may get many 'struct map' holding references to the '/usr/lib64/libc-2.20.so' DSO but then at some point some DSO may have no references but we still don't want to straight away release its resources, because "soon" we may get a new 'struct map' that needs it and we want to reuse its symtab or other resources. So we need some way to garbage collect it when crossing some memory usage threshold, which is left for anoter patch, for now it is sufficient to release it when calling dsos__exit(), i.e. when deleting the whole list as part of deleting the 'struct machine' containing it, which will leave only referenced objects being used. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/n/tip-majzgz07cm90t2tejrjy4clf@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Protect accesses the dso rbtrees/lists with a rw lock

2015-06-08T13:31:40+00:00

To allow concurrent access, next step: refcount struct dso instances, so that we can ditch unused them when the last map pointing to it goes away. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/n/tip-yk1k08etpd2aoe3tnrf0oizn@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Fix up vdso methods names

2015-05-29T15:43:44+00:00

To make it consistent with the other dso lifetime routines. For instance: struct dso *vdso__new(struct machine *machine, const char *short_name, const char *long_name) Becomes: struct dso *machine__addnew_vdso(struct machine *machine, const char *short_name, const char *long_name) Because: 1) There is no 'struct vdso' for us to have vdso__ prefixed routines. 2) Because it will not really just create a new instance of 'struct dso', it'll call dso__new() but it will also insert it into the DSO's list/rbtree, and we have a method name for that: 'addnew', just like we have dsos__addnew(). 3) So it is really a 'struct machine' operation, it is the first argument, etc. This way the place where this is used gets consistent: if (vdso) { pgoff = 0; - dso = vdso__dso_findnew(machine, thread); + dso = machine__findnew_vdso(machine, thread); } else dso = machine__findnew_dso(machine, filename); Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/n/tip-r3w3tvh8exm9xfz3p4tz9qbz@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf machine: No need to have two DSOs lists

2015-05-29T15:43:43+00:00

We can, given a DSO, figure out if it is a kernel, a kernel module or a userlevel DSO, so stop having to process two lists in several functions. If searching becomes an issue at some point, we can have them in a rbtree, etc. Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-s4yb0onpdywu6dj2xl9lxi4t@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Do not attempt to run perf-read-vdso32 if it wasn't built

2014-10-29T12:32:48+00:00

popen() causes an error message to print if perf-read-vdso32 does not run. Avoid that by not trying to run it if it was not built. Ditto perf-read-vdsox32. Signed-off-by: Adrian Hunter Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1414061124-26830-17-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add support for 32-bit compatibility VDSOs

2014-10-29T12:32:48+00:00

'perf record' post-processes the event stream to create a list of build-ids for object files for which sample events have been recorded. That results in those object files being recorded in the build-id cache. In the case of VDSO, perf tools reads it from memory and copies it into a temporary file, which as decribed above, gets added to the build-id cache. Then when the perf.data file is processed by other tools, the build-id of VDSO is listed in the perf.data file and the VDSO can be read from the build-id cache. In that case the name of the map, the short name of the DSO, and the entry in the build-id cache are all "[vdso]". However, in the 64-bit case, there also can be 32-bit compatibility VDSOs. A previous patch added programs "perf-read-vdso32" and "perf read-vdsox32". This patch uses those programs to read the correct VDSO for a thread and create a temporary file just as for the 64-bit VDSO. The map name and the entry in the build-id cache are still "[vdso]" but the DSO short name becomes "[vdso32]" and "[vdsox32]" respectively. Signed-off-by: Adrian Hunter Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1414061124-26830-16-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Build programs to copy 32-bit compatibility

2014-10-29T12:32:48+00:00

perf tools copy VDSO out of memory. However, on 64-bit machines there may be 32-bit compatibility VDOs also. To copy those requires separate 32-bit executables. This patch adds to the build additional programs perf-read-vdso32 and perf-read-vdsox32 for 32-bit and x32 respectively. Signed-off-by: Adrian Hunter Cc: Peter Zijlstra Cc: David Ahern Cc: Frederic Weisbecker , Cc: Jiri Olsa Cc: Namhyung Kim Cc: Paul Mackerras Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1414061124-26830-15-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo