lwn.git/tools/perf/util/module.c, branch docs-next

perf tools: Rewrite and improve support for kernel modules

2009-10-02T08:48:42+00:00

Representing modules as struct map entries, backed by a DSO, etc, using /proc/modules to find where the module is loaded. DSOs now can have a short and long name, so that in verbose mode we can show exactly which .ko or vmlinux image was used. As kernel modules now are a DSO separate from the kernel, we can ask for just the hits for a particular set of kernel modules, just like we can do with shared libraries: [root@doppio linux-2.6-tip]# perf report -n --vmlinux /home/acme/git/build/tip-recvmmsg/vmlinux --modules --dsos \[drm\] | head -15 84.58% 13266 Xorg [k] drm_clflush_pages 4.02% 630 Xorg [k] trace_kmalloc.clone.0 3.95% 619 Xorg [k] drm_ioctl 2.07% 324 Xorg [k] drm_addbufs 1.68% 263 Xorg [k] drm_gem_close_ioctl 0.77% 120 Xorg [k] drm_setmaster_ioctl 0.70% 110 Xorg [k] drm_lastclose 0.68% 106 Xorg [k] drm_open 0.54% 85 Xorg [k] drm_mm_search_free [root@doppio linux-2.6-tip]# Specifying --dsos /lib/modules/2.6.31-tip/kernel/drivers/gpu/drm/drm.ko would have the same effect. Allowing specifying just 'drm.ko' is left for another patch. Processing kallsyms so that per kernel module struct map are instantiated was also left for another patch. That will allow removing the module name from each of its symbols. struct symbol was reduced by removing the ->module backpointer and moving it (well now the map) to struct symbol_entry in perf top, that is its only user right now. The total linecount went down by ~500 lines. Signed-off-by: Arnaldo Carvalho de Melo Cc: Frédéric Weisbecker Cc: "H. Peter Anvin" Cc: Peter Zijlstra Cc: Mike Galbraith Cc: Avi Kivity Signed-off-by: Ingo Molnar

perf tools: Fix buffer allocation

2009-09-24T13:11:23+00:00

"perf top" cores dump on my dev machine, if run from a directory where vmlinux is present: *** glibc detected *** malloc(): memory corruption: 0x085670d0 *** Signed-off-by: Eric Dumazet Cc: LKML-Reference: <4ABB6EB7.7000002@gmail.com> Signed-off-by: Ingo Molnar

perf tools: Handle relative paths while loading module symbols

2009-09-24T09:40:35+00:00

Inform util/module.c::mod_dso__load_module_paths() that relative paths do exist in some modules.dep, and make it fail noisily should it encounter a path that it doesn't understand, or a module it cannot open. Reported-by: Avi Kivity Signed-off-by: Mike Galbraith Cc: Arnaldo Carvalho de Melo Cc: rostedt@goodmis.org Cc: Mathieu Desnoyers Cc: Peter Zijlstra Cc: Frederic Weisbecker Cc: Masami Hiramatsu LKML-Reference: <1253779628.10513.8.camel@marge.simson.net> Signed-off-by: Ingo Molnar

perf: Enable more compiler warnings

2009-08-16T08:47:47+00:00

Related to a shadowed variable bug fix Valdis Kletnieks noticed that perf does not get built with -Wshadow, which could have helped us avoid the bug. So enable -Wshadow and also enable the following warnings on perf builds, in addition to the already enabled -Wall -Wextra -std=gnu99 warnings: -Wcast-align -Wformat=2 -Wshadow -Winit-self -Wpacked -Wredundant-decls -Wstack-protector -Wstrict-aliasing=3 -Wswitch-default -Wswitch-enum -Wno-system-headers -Wundef -Wvolatile-register-var -Wwrite-strings -Wbad-function-cast -Wmissing-declarations -Wmissing-prototypes -Wnested-externs -Wold-style-definition -Wstrict-prototypes -Wdeclaration-after-statement And change/fix the perf code to build cleanly under GCC 4.3.2. The list of warnings enablement is rather arbitrary: it's based on my (quick) reading of the GCC manpages and trying them on perf. I categorized the warnings based on individually enabling them and looking whether they trigger something in the perf build. If i liked those warnings (i.e. if they trigger for something that arguably could be improved) i enabled the warning. If the warnings seemed to come from language laywers spamming the build with tons of nuisance warnings i generally kept them off. Most of the sign conversion related warnings were in this category. (A second patch enabling some of the sign warnings might be welcome - sign bugs can be nasty.) I also kept warnings that seem to make sense from their manpage description and which produced no actual warnings on our code base. These warnings might still be turned off if they end up being a nuisance. I also left out a few warnings that are not supported in older compilers. [ Note that these changes might break the build on older compilers i did not test, or on non-x86 architectures that produce different warnings, so more testing would be welcome. ] Reported-by: Valdis.Kletnieks@vt.edu Cc: Peter Zijlstra Cc: Mike Galbraith Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker LKML-Reference: Signed-off-by: Ingo Molnar

perf_counter tools: Add infrastructure to support loading of kernel module symbols

2009-07-02T06:42:20+00:00

Add infrastructure for module path discovery and section load addresses. Signed-off-by: Mike Galbraith Cc: Peter Zijlstra Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo LKML-Reference: <1246514830.13293.44.camel@marge.simson.net> Signed-off-by: Ingo Molnar