57f95bf5f8
The dwarf_getsrc_die() can return the line which is not a statement nor
the least line number among the lines which shares same address.
This can lead perf probe --list shows incorrect line number for probed
address.
To fix this, this introduces cu_getsrc_die() which returns only a
statement line and which is the least line number (we call it the
representive line for an address), and use it in cu_find_lineinfo().
Also, if the given address is the entry address of a real function,
cu_find_lineinfo() returns the function declared line number instead of
the start line number of the function body.
For example, without this change perf probe -l shows incorrect line as
below.
# perf probe -a kernel_read:2
Added new event:
probe:kernel_read (on kernel_read:2)
You can now use it in all perf tools, such as:
perf record -e probe:kernel_read -aR sleep 1
# perf probe -l
probe:kernel_read (on kernel_read:1@linux-5.0.0/fs/read_write.c)
With this fix, it shows correct line number as below;
# perf probe -l
probe:kernel_read (on kernel_read:2@linux-5.0.0/fs/read_write.c)
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Link: http://lore.kernel.org/lkml/157406471067.24476.17463149618465494448.stgit@devnote2
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.