Fix buggy-looking code which unnecessarily adjusts the file offset
fields read from /proc/*/maps.
This may have gone unnoticed since the offset is usually 0 (and the
logic in util/symbol.c may work incorrectly for other offset values).
Commiter note:
This fixes a bug introduced in 4af8b35, there is no need to shift pgoff
twice, the show_map_vma routine in fs/proc/task_mmu.c already converts
it from the number of pages to the size in bytes, and that is what
appears in /proc/PID/map.
Cc: Nicolas Pitre <[email protected]>
Cc: Will Deacon <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Dave Martin <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Changes:
* Simplification of the main search loop on dso__load()
* Replace the search with a 2-pass search:
* First, try to find an image with a proper symtab.
* Second, repeat the search, accepting dynsym.
A second scan should only ever happen when needed debug images are
missing from the buildid cache or stale, i.e., when the cache is out of
sync.
Currently, the second scan also happens when using separated debug
images, since the caching logic doesn't currently know how to cache
those. Improvements to the cache behaviour ought to solve that.
Signed-off-by: Dave Martin <[email protected]>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
If we have a buildid, then we never want to load an image which has no buildid,
or which has a different buildid, so it makes sense for the check to be built
into dso__load and not done separately. This is fine for old distros which
don't use buildid at all since we do no check in that case.
This refactoring also alleviates some subtle race condition issues by not
opening ELF images twice to check the buildid and then load the symbols, which
could lead to weirdness if an image is replaced under our feet.
Signed-off-by: Dave Martin <[email protected]>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
Tidy-up patch to remove some code and struct perf_session data members
which are no longer needed due to the previous patch: "perf tools: Don't
abbreviate file paths relative to the cwd".
LKML-Reference: <new-submission>
Signed-off-by: Dave Martin <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
This avoids around some problems where the full path is executables and DSOs it
needed for finding debug symbols on platforms with separated debug symbol files
such as Ubuntu. This is simpler than tracking an extra name for each image.
The only impact should be that paths in verbose output from the perf tools
become absolute, instead of relative to .
LKML-Reference: <new-submission>
Signed-off-by: Dave Martin <[email protected]>
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>