At various places, there were either some assumption that the 'end'
boundary (highest address) was either not included, included,
or was the highest addressable word, or the highest addressable byte.
This e.g. was very visible when doing:
./vg-in-place -d -d ./helgrind/tests/tc01_simple_race|&grep regi
giving
--24040:2:stacks register 0xBEDB4000-0xBEDB4FFF as stack 0
--24040:2:stacks register 0x402C000-0x4A2C000 as stack 1
showing that the main stack end was (on x86) not the highest word
but the highest byte, while for the thread 1, the registered end
was a byte not part of the stack.
The attached patch ensures that stack bounds semantic are documented and
consistent. Also, some of the stack handling code is factorised.
The convention that the patch ensures and documents is:
start is the lowest addressable byte, end is the highest addressable byte.
(the words 'min' and 'max' have been kept when already used, as this wording is
consistent with the new semantic of start/end).
In various debug log, used brackets [ and ] to make clear that
both bounds are included.
The code to guess and register the client stack was duplicated
in all the platform specific syswrap-<plat>-<os>.c files.
Code has been factorised in syswrap-generic.c
The patch has been regression tested on
x86, amd64, ppc32/64, s390x.
It has been compiled and one test run on arm64.
Not compiled/not tested on darwin, android, mips32/64, arm
More in details, the patch does the following:
coregrind/pub_core_aspacemgr.h
include/valgrind.h
include/pub_tool_machine.h
coregrind/pub_core_scheduler.h
coregrind/pub_core_stacks.h
- document start/end semantic in various functions
also in pub_tool_machine.h:
- replaces unclear 'bottommost address' by 'lowest address'
(unclear as stack bottom is or at least can be interpreted as
the 'functional' bottom of the stack, which is the highest
address for 'stack growing downwards').
coregrind/pub_core_initimg.h
replace unclear clstack_top by clstack_end
coregrind/m_main.c
updated to clstack_end
coregrind/pub_core_threadstate.h
renamed client_stack_highest_word to client_stack_highest_byte
coregrind/m_scheduler/scheduler.c
computes client_stack_highest_byte as the highest addressable byte
Update comments in call to VG_(show_sched_status)
coregrind/m_machine.c
coregrind/m_stacktrace.c
updated to client_stack_highest_byte, and switched
stack_lowest/highest_word to stack_lowest/highest_byte accordingly
coregrind/m_stacks.c
clarify semantic of start/end,
added a comment to indicate why we invert start/end in register call
(note that the code find_stack_by_addr was already assuming that
end was included as the checks were doing e.g.
sp >= i->start && sp <= i->end
coregrind/pub_core_clientstate.h
coregrind/m_clientstate.c
renames Addr VG_(clstk_base) to Addr VG_(clstk_start_base)
(start to indicate it is the lowest address, base suffix kept
to indicate it is the initial lowest address).
coregrind/m_initimg/initimg-darwin.c
updated to VG_(clstk_start_base)
replace unclear iicii.clstack_top by iicii.clstack_end
updated clstack_max_size computation according to both bounds included.
coregrind/m_initimg/initimg-linux.c
updated to VG_(clstk_start_base)
updated VG_(clstk_end) computation according to both bounds included.
replace unclear iicii.clstack_top by iicii.clstack_end
coregrind/pub_core_aspacemgr.h
extern Addr VG_(am_startup) : clarify semantic of the returned value
coregrind/m_aspacemgr/aspacemgr-linux.c
removed a copy of a comment that was already in pub_core_aspacemgr.h
(avoid double maintenance)
renamed unclear suggested_clstack_top to suggested_clstack_end
(note that here, it looks like suggested_clstack_top was already
the last addressable byte)
* factorisation of the stack guessing and registration causes
mechanical changes in the following files:
coregrind/m_syswrap/syswrap-ppc64-linux.c
coregrind/m_syswrap/syswrap-x86-darwin.c
coregrind/m_syswrap/syswrap-amd64-linux.c
coregrind/m_syswrap/syswrap-arm-linux.c
coregrind/m_syswrap/syswrap-generic.c
coregrind/m_syswrap/syswrap-mips64-linux.c
coregrind/m_syswrap/syswrap-ppc32-linux.c
coregrind/m_syswrap/syswrap-amd64-darwin.c
coregrind/m_syswrap/syswrap-mips32-linux.c
coregrind/m_syswrap/priv_syswrap-generic.h
coregrind/m_syswrap/syswrap-x86-linux.c
coregrind/m_syswrap/syswrap-s390x-linux.c
coregrind/m_syswrap/syswrap-darwin.c
coregrind/m_syswrap/syswrap-arm64-linux.c
Some files to look at more in details:
syswrap-darwin.c : the handling of sysctl(kern.usrstack) looked
buggy to me, and has probably be made correct by the fact that
VG_(clstk_end) is now the last addressable byte. However,unsure
about this, as I could not find any documentation about
sysctl(kern.usrstack). I only find several occurences on the web,
showing that the result of this is page aligned, which I guess
means it must be 1+ the last addressable byte.
syswrap-x86-darwin.c and syswrap-amd64-darwin.c
I suspect the code that was computing client_stack_highest_word
was wrong, and the patch makes it correct.
syswrap-mips64-linux.c
not sure what to do for this code. This is the only code
that was guessing the stack differently from others.
Kept (almost) untouched. To be discussed with mips maintainers.
coregrind/pub_core_libcassert.h
coregrind/m_libcassert.c
* void VG_(show_sched_status):
renamed Bool valgrind_stack_usage to Bool stack_usage
if stack_usage, shows both the valgrind stack usage and
the client stack boundaries
coregrind/m_scheduler/scheduler.c
coregrind/m_gdbserver/server.c
coregrind/m_gdbserver/remote-utils.c
Updated comments in callers to VG_(show_sched_status)
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14392
Activating this hint using --sim-hints=no-nptl-pthread-stackcache
means the glibc nptl stack cache will be disabled.
Disabling this stack/tls cache avoids helgrind false positive race conditions
errors when using __thread variables.
Note: disabling the stack cache is done by a kludge, dependent on
internal knowledge of glibc code, and using libpthread debug info.
So, this kludge might be broken with newer glibc version.
This has been tested on various platforms and various
glibc versions 2.11, 2.16 and 2.18
To check if the disabling works, you can do:
valgrind --tool=helgrind --sim-hints=no-nptl-pthread-stackcache -d -v ./helgrind/tests/tls_threads |& grep kludge
If you see the below 2 lines, then hopefully the stack cache has been disabled.
--12624-- deactivate nptl pthread stackcache via kludge: found symbol stack_cache_actsize at addr 0x3AF178
--12624:1:sched pthread stack cache size disabling done via kludge
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14313
relatively minor extensions to m_debuginfo, a major overhaul of
m_debuginfo/readdwarf3.c to get its space usage under control, and
changes throughout the system to enable heap-use profiling.
The majority of the merged changes were committed into
branches/PTRCHECK as the following revs: 8591 8595 8598 8599 8601 and
8161.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@8621
branch hereby becomes inactive. This currently breaks everything
except x86; fixes for amd64/ppc32 to follow.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@5520
- Move VG_(fd_{soft,hard}_limit) into m_clientstate
- m_main: clean up auxv handling. Get rid of scan_auxv().
- m_main: move scan_colsep() to somewhere more sensible.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4799
changes from r4341 through r4787 inclusive). That branch is now dead.
Please do not commit anything else to it.
For the most part the merge was not troublesome. The main areas of
uncertainty are:
- build system: I had to import by hand Makefile.core-AM_CPPFLAGS.am
and include it in a couple of places. Building etc seems to still
work, but I haven't tried building the documentation.
- syscall wrappers: Following analysis by Greg & Nick, a whole lot of
stuff was moved from -generic to -linux after the branch was created.
I think that is satisfactorily glued back together now.
- Regtests: although this appears to work, no .out files appear, which
is strange, and makes it hard to diagnose regtest failures. In
particular memcheck/tests/x86/scalar.stderr.exp remains in a
conflicted state.
- amd64 is broken (slightly), and ppc32 will be unbuildable. I'll
attend to the former shortly.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4789
