This change adds some handling for the equivalent of Solaris' PGRAB_*
flags. In particular, support for PGRAB_RDONLY is needed to avoid a
nasty deadlock: dtrace(1) may otherwise stop the master process for its
pseudo-terminal and end up blocking while writing to standard output.
When looking up an object by name, allow prefix matches if no direct match
is found. This allows one to, for example, match libc entry probes with:
# dtrace -n 'pid$target:libc.so::entry' -c ./foo
instead of requiring "libc.so.7" or a glob.
Also remove proc_obj2map() as it currently just duplicates the
functionality of proc_name2map(). It's supposed to take a Solaris
link-map ID as a paramter, but support for this isn't implemented and
isn't required to support DTrace's pid provider.
libproc previously created a new handle for each symbol lookup, which
gives rather egregious performance for DTrace's ustack() action. With
this change libproc will cache the libelf descriptor upon access, making
lookups much faster in the common case.
This allows librtld_db to fetch the PID from a handle without calling into
libproc. Together with r303531, this means that librtld_db no longer
references symbols from libproc.
This is used by libdtrace to determine the data model of target processes.
This allows for the creation of pid provider probes in 32-bit processes on
amd64.
MFC after: 1 month
modifications to libproc to support fetching the CTF info for a given file.
With this change, dtrace(1) is able to resolve type info for function and
USDT probe arguments, and function return values. In particular, the args[n]
syntax should now work for referencing arguments of userland probes,
provided that the requisite CTF info is available.
The uctf tests pass if the test programs are compiled with CTF info. The
current infrastructure around the DTrace test suite doesn't support this
yet.
Differential Revision: https://reviews.freebsd.org/D891
MFC after: 1 month
Relnotes: yes
Sponsored by: EMC / Isilon Storage Division
o return the correct status in proc_wstatus()
o proc_read takes a void *
o correctly allocate the objs structure array
Sponsored by: The FreeBSD Foundation
* breakpoint setup support
* register query
* symbol to address mapping and vice-versa
* more misc utility functions based on their Solaris counterpart
Also, I've written some test cases.
Sponsored by: The FreeBSD Foundation
These will be fleshed out as part of the DTrace userland tracing
development.
For now, the kernel tracing part of DTrace requires minimal functionality
for this library.
The API for this library is deliberately different from the libproc in
OpenSolaris due to licensing restrictions.
