The checkpoint plugin watches for writes on the given symbol and logs
the written value and the simulation time to a given output file.
Additionally, a SHA1 hash is computed over all memory locations between
given start and stop symbols.
On x86, virtual memory is disabled while computing the checkpoint hash.
This means the checkpoint plugin in checksumming over physical, not
virtual, address ranges! This can result to unexpected behaviour if
virtual memory is not used for identity paging.
To save checkpoint information to a file, use the Checkpoint constructor
with a given checkpoint symbol and add the plugin to the experiment (flow).
To check checkpoints against an existing file, use the constructor without
memory symbol and do not add the plugin to the experiment. Instead, define
a memory listener "manually" and call the check() function. This approach
was taken as the simplest form of cooperation between experiment and
plugins.
For SHA1 calculation, C code from RFC 3174 is used to prevent depending
on another external library. However, this may not be the fastest or
best code for the task.
TEMPORARY HACK/WORKAROUND:
Since dOSEK uses the highest bit (31) of some pointers for parity and
the checksum plugin reads these (stack) pointers to determine checksum
regions, the plugin currently DISCARDS BIT 31 of pointers used as
dynamic region limits.
This will be replaced in the future by a callback mechanism, which lets
the experiment specify the regions to checksum (called at each checkpoint).
Change-Id: I176eccc34b582bbf13e52b6943191dd20258acc5
Somehow, while iterating symbols in a section, it can happen that the last
symbol start address is equal to the section size, which means it is beyond
the section end.
In this case the LLVM getInstruction() method does not return a failure, but a
zero-size instruction, resulting in an infinite loop.
Now, if beyond section limits, the iteration is aborted.
Additionally, an assertion checks for disassembled zero-size instructions.
Change-Id: Id8a355475161150d3ee919cd6cf603d4ff26b228
Internal LLVM register IDs can and did change between LLVM versions.
These magic integers are replaced by iterating over all LLVM registers
and mapping them to FAIL* registers by name.
As this iteration requires a LLVM object created from a binary, a static
convenience function is added to LLVMtoFailTranslator which creates a
translator given the binary filename. Building this functionality inside
libfail-llvmdisassembler prevents experiments from needing to add LLVM
includes and library definitions.
Change-Id: I27927f40d5cb6d9a22bb2caf21ca2450f6bcb0b8
new register type RT_CONTROL:
CR0, CR2, CR3, CR4
new register type RT_SEGMENT:
CS, DS, ES, FS, GS, SS
Reading/writing is mostly untested except for CR3...
Change-Id: I0d0fba4a1669153ab2577e82ab64a04cf2bbfb94
CMake does not support linker groups, which were used to "automatically"
fix circular dependencies between different static FAIL* libraries and
the ordering of dynamic external libraries broke linking.
CMake can however correctly invoke the linker if dependencies are decribed
correctly (even if circular). This required changing all add_dependencies
calls between libraries to target_link_libraries (which creates a link-time
dependency) and linking all experiments to fail-sal.
Change-Id: I3a0d5dddb9b3d963ef538814e20d6b3de85d4ec5
If the queue for outbound jobs is not unlimited, experiment rows are fetched
from the DB server continuously as experiments finish. When this takes too
long the connection to the DB server can be lost. The code did not check for
a mysql_error and assumed the result set was fetched completely, thus skipping
a potentially large amount of experiments (in our case only ~20000 of 400000+
experiments were run).
This change adds checks to determine if the result fetch loop was finished due
to an error and checks the sent pilot count to the unfinished experiment count.
Additionally, the mysql result object is correctly freed.
The underlying problem of MySQL connection loss can hopefully be prevented by
increasing timeouts in the MySQL config as described in doc/how-to-build.txt.
To prevent the problem from occurring when this is forgotten, this change
reverts the default job queue length to be unlimited (SERVER_OUT_QUEUE_SIZE=0),
at the cost of increased memory usage.
Change-Id: I09d9faddd8190c6dd5fbe733a0679a733d5837ec
The database queries to fetch all unfinished experiments were broken.
The server tried to insert all finished pilot_ids into the temporary
result_ids table and then discard all experiments which have the correct
(finished) count of IDs in this table. This cannot work as the pilot_id
is the only column of result_ids and must be a unique primary key.
As a fix, the count of results is stored as a second field in result_ids
and the result table is now joined against result_ids to check this field.
Change-Id: I6a9fb774825f0cc4ce104c6e51d7b2fe16957aec
A simple plugin which deterministically returns a new random value
each time the specified symbol is read.
Change-Id: I6ccac421fc064f02a88e8b126f8a26044d1f51c6
Change the aspect weaver project path to all source paths (src, simulators,
debuggers, tools) and the <build>/src path.
Without this change "external" builds do work but do not weave in any
experiments. This change also allows multiple build directories within the
project root, as the weaver will no longer use aspects from all builds.
When further source directories are added to the project root, these
definitions will need to be updated.
Change-Id: If3d3d9fe61427fcba8b815171c8acdcdeb06cb69
