perf buildid-cache: Add ability to add kcore to the cache
kcore can be used to view the running kernel object code. However, kcore changes as modules are loaded and unloaded, and when the kernel decides to modify its own code. Consequently it is useful to create a copy of kcore at a particular time. Unlike vmlinux, kcore is not unique for a given build-id. And in addition, the kallsyms and modules files are also needed. The tool therefore creates a directory: ~/.debug/[kernel.kcore]/<build-id>/<YYYYmmddHHMMSShh> which contains: kcore, kallsyms and modules. Note that the copied kcore contains only code sections. See the kcore_copy() function for how that is determined. The tool will not make additional copies of kcore if there is already one with the same modules at the same addresses. Currently, perf tools will not look for kcore in the cache. That is addressed in another patch. Signed-off-by:Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/525BF849.5030405@intel.com [ renamed 'index' to 'idx' to avoid shadowing string.h symbol in f12, use at least one member initializer when initializing a struct to zeros, also to fix the build on f12 ] Signed-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com>
parent
1179e11b
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