All syscalls with the "at" suffix rely on a directory file descriptor
(dirfd) and a pathname, provided as arguments to the syscall
If the pathname is relative, then it is interpreted relative to the
directory referred to by the file descriptor dirfd (rather than relative
to the current working directory of the calling process)
Prior to this patch, only the openat syscall was properly implemented.
Other syscalls were discarding the dirfd argument and producing
a warning instead
JIRA: https://gem5.atlassian.net/browse/GEM5-1098
Change-Id: I0cc20c6ef79fca8c8d1c2c9a52eb54ede3d51312
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/51048
Reviewed-by: Richard Cooper <richard.cooper@arm.com>
Reviewed-by: Gabe Black <gabe.black@gmail.com>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
When clone is called with the VFORK flag, the calling process is
suspended until the child process either exits, or calls execve.
This patch adds in a new variable to Process, which is used to store the
context of the calling process if this process is created through a
clone with VFORK set.
This patch also adds the required support in clone to suspend the
calling thread, and in exitImpl and execveFunc to wake up the calling
thread when the child thread calls either of those functions
Change-Id: I85af67544ea1d5df7102dcff1331b5a6f6f4fa7c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/48346
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
There were three things preventing execve from working
Firstly, the entrypoint for the new program wasn't correct. This was
fixed by calling Process::init, which adds a bias to the entrypoint.
Secondly, the uname string wasn't being copied over. This meant when the
new executable tried to run, it would think the kernel was too old to
run on, and would error out. This was fixed by copying over the uname
string (the `release` string in Process) when creating the new process.
Additionally, this patch also ensures we copy over the uname string in
the clone implementation, as otherwise a cloned thread that called
execve would crash.
Finally, we choose to not delete the new ProcessParams or the old
Process. This is done both because it matches what is done in cloneFunc,
but also because deleting the old process results in a segfault later
on.
Change-Id: I4ca201da689e9e37671b4cb477dc76fa12eecf69
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/48345
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Matt Sinclair <mattdsinclair@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The proxies are not used on the critical path, and it's usually implicit
whether they should be the FS or SE version.
Ideally in the future we won't need to worry about which version we need
to use, but the differences haven't quite been abstracted away, and
occasionally we need to decide between the two.
Change-Id: Idb363d6ddc681f7c1ad5e7aba69865f40aa30dc8
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/45907
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Apply the gem5 namespace to the codebase.
Some anonymous namespaces could theoretically be removed,
but since this change's main goal was to keep conflicts
at a minimum, it was decided not to modify much the
general shape of the files.
A few missing comments of the form "// namespace X" that
occurred before the newly added "} // namespace gem5"
have been added for consistency.
std out should not be included in the gem5 namespace, so
they weren't.
ProtoMessage has not been included in the gem5 namespace,
since I'm not familiar with how proto works.
Regarding the SystemC files, although they belong to gem5,
they actually perform integration between gem5 and SystemC;
therefore, it deserved its own separate namespace.
Files that are automatically generated have been included
in the gem5 namespace.
The .isa files currently are limited to a single namespace.
This limitation should be later removed to make it easier
to accomodate a better API.
Regarding the files in util, gem5:: was prepended where
suitable. Notice that this patch was tested as much as
possible given that most of these were already not
previously compiling.
Change-Id: Ia53d404ec79c46edaa98f654e23bc3b0e179fe2d
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46323
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
sched_getaffinity is different from other syscalls in the raw syscall
return the size of the cpumask being used to represent the CPU bit mask.
Because of this, when a library (libnuma in this case) directly called
sched_getaffinity and got a return value of 0, it errored out, thinking
that there were no CPUs available.
This implementation assumes that all CPUs are available, so it sets
all simulated CPUs in the bitmask
Change-Id: Id95c919986cc98a411877056256604f57a29f0f9
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46243
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Add serialization of the fd array when checkpointing in SE mode.
With this patch, host backed files are restored.
Further work needs to be done for restoring other types of
file descriptor.
As the file path saved is relative, on restoration of the checkpoint,
it may fail to open the file if the path is no longer valid.
If it cannot open the file, it will exit the simulation
with a meaningful error message.
Change-Id: I4d0c7cd614a8abaffcae9aba1a28c9fdbc023c5a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/46619
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
As part of recent decisions regarding namespace
naming conventions, all namespaces will be changed
to snake case.
sim_clock::Int became sim_clock::as_int.
"as_int" was chosen because "int" is a reserved
keyword, and this namespace acts as a selector of
how to read the internal variables.
Another possibility to resolve this would be to
remove the namespaces "Float" and "Int" and use
unions instead.
Change-Id: I65f47608d2212424bed1731c7f53d242d5a7d89a
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/45436
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Hoa Nguyen <hoanguyen@ucdavis.edu>
Maintainer: Gabe Black <gabe.black@gmail.com>
We currently use the traditional SI-like prefixes to represent
binary multipliers in some contexts. This is ambiguous in many cases
since they overload the meaning of the SI prefix.
Here are some examples of commonly used in the industry:
* Storage vendors define 1 MB as 10**6 bytes
* Memory vendors define 1 MB as 2**20 bytes
* Network equipment treats 1Mbit/s as 10**6 bits/s
* Memory vendors define 1Mbit as 2**20 bits
In practice, this means that a FLASH chip on a storage bus uses
decimal prefixes, but that same flash chip on a memory bus uses binary
prefixes. It would also be reasonable to assume that the contents of a
1Mbit FLASH chip would take 0.1s to transfer over a 10Mbit Ethernet
link. That's however not the case due to different meanings of the
prefix.
The quantity 2MX is treated differently by gem5 depending on the unit
X:
* Physical quantities (s, Hz, V, A, J, K, C, F) use decimal prefixes.
* Interconnect and NoC bandwidths (B/s) use binary prefixes.
* Network bandwidths (bps) use decimal prefixes.
* Memory sizes and storage sizes (B) use binary prefixes.
Mitigate this ambiguity by consistently using the ISO/IEC/SI prefixes
for binary multipliers for parameters and comments where appropriate.
Change-Id: I797163c8690ae0092e00e371d75f5e7cebbcd1f5
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/39579
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
When a gem5 op is triggered using a KVM MMIO exit event, the PC has
already been advanced beyond the offending instruction. Normally when
a system call or gem5 op is triggered, the PC has not advanced because
the instruction hasn't actually finished executing. This means that if
a gem5 op, and by extension a system call in SE mode, want to advance
the PC to the instruction after the gem5 op, they have to check whether
they were triggered from KVM.
To avoid having to special case these sorts of situations (currently
only in the clone system call), we can have the code which dispatches to
gem5 ops from KVM adjust the next PC so that it points to what the
current PC is. That way the PC can be advanced unconditionally, and will
point to the instruction after the one that triggered the call.
To be fully consistent, we would also need to adjust the current PC.
That would be non-trivial since we'd have to figure out where the
current instruction started, and that may not even be possible to
unambiguously determine given x86's instruction structure. Then we would
also need to restore the original PC to avoid confusing KVM.
Change-Id: I9ef90b2df8e27334dedc25c59eb45757f7220eea
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/38486
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Inside the code of cloneFunc(…) //syscall_emul.hh
cp->initState(); //line 1483
p->clone(tc, ctc, cp, flags); //line 1484
…
ctc->clearArchRegs(); //line 1503
OS::archClone(flags, p, cp, tc, ctc, newStack, tlsPtr); //line 1505
…
At line 1483, initState() is called and the activateContext() of the
corresponding MinorCPU is eventually called. The actual architecture
clone happens at line 1505 where PC of the new thread could have a
correct value.
In the existing implementation of MinorCPU::activateContext(ThreadID
thread_id), the below line 275 is called
pipeline->wakeupFetch(thread_id);
to start fetching instruction with current value of PC, which is 0x0,
leading to panic “Page table fault when accessing virtual address 0”.
This is because the OS::archClone() is not yet called. So, the below bug
fix handles the wakeup fetch for a thread for two scenarios:
...
if (!threads[thread_id]->getUseForClone())
{ //the thread is not cloned
pipeline->wakeupFetch(thread_id);
} else {//the thread from clone
if (fetchEventWrapper != NULL)
delete fetchEventWrapper;
fetchEventWrapper = new EventFunctionWrapper([this, thread_id]
{pipeline->wakeupFetch(thread_id);}, "wakeupFetch");
schedule(*fetchEventWrapper, clockEdge(Cycles(0)));
}
...
If a thread is not cloned, pipeline->wakeupFetch() is called
immediately.
For the cloned thread, the above bug fix delays the execution of
pipeline->wakeupFetch()
after the OS::archClone is done. ThreadContext::getUseForClone() return
true if a thread is cloned.
A member variable fetchEventWrapper is added to MinorCPU class for
delayed fetch event.
A member variable useForClone and its corresponding get/set methods are
added to ThreadContext class. This approach allows future reuse of this
useForClone variable by other CPU models if needed and also avoid lots
of changes resulted by modifying parameters of activateContext () and
activate() which are defined as override.
Inside the syscall cloneFunc, the useForClone member of a ThreadContext
object is set via its set method right before Process's initState() is
called, shown as below.
ctc->setUseForClone(true);
cp->initState();
p->clone(tc, ctc, cp, flags);
A few previously failed RISC-V ASM tests have been open in tests.py file
after the bug fix works.
JIRA issue: https://gem5.atlassian.net/browse/GEM5-374
Change-Id: Ibffe46522e2617443d29f49df180692c54830f14
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/37315
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
This is no longer willing to implicitly cast between the locally defined
Linux::fd_set type and the system fd_set type. That's pretty reasonable
since those types are really independent of one another, and we
shouldn't be using them interchangeably in the first place. That's a
pre-existing condition though, and I just want to get the existing code
to compile for now.
Change-Id: I41d5f3695dfe5f0e406d074d31d13c6e3282df64
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/33415
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The System class has a few different arrays of values which each
correspond to a thread of execution based on their position. This
change collects them together into a single class to make managing them
easier and less error prone. It also collects methods for manipulating
those threads as an API for that class.
This class acts as a collection point for thread based state which the
System class can look into to get at all its state. It also acts as an
interface for interacting with threads for other classes. This forces
external consumers to use the API instead of accessing the individual
arrays which improves consistency.
Change-Id: Idc4575c5a0b56fe75f5c497809ad91c22bfe26cc
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/25144
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Instead of calling into object files after the fact and asking them to
put symbols into a target symbol table, this change makes object files
fill in a symbol table themselves at construction. Then, that table can
be retrieved and used to fill in aggregate tables, masked, moved,
and/or filtered to have only one type of symbol binding.
This simplifies the symbol management API of the object file types
significantly, and makes it easier to deal with symbol tables alongside
binaries in the FS workload classes.
Change-Id: Ic9006ca432033d72589867c93d9c5f8a1d87f73c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24787
Reviewed-by: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This singleton object is used thruoughout the simulator. There is
really no reason not to have it statically allocated, except that
whether it was allocated seems to sometimes be used as a signal that
something already put symbols in it, specifically in SE mode.
To keep that functionality for the moment, this change adds an "empty"
method to the SymbolTable class to make it easy to check if the symbol
table is empty, or if someone already populated it.
Change-Id: Ia93510082d3f9809fc504bc5803254d8c308d572
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24785
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The components in base/loader were moved into a namespace called
Loader. This will make it easier to add loader components with fairly
short natural names which don't invite name collisions.
gem5 should use namespaces more in general for that reason and to make
it easier to write independent components without having to worry about
name collisions being added in the future.
Unfortunately this namespace has the same name as a class used to load
an object file into a process object. These names can be disambiguated
because the Process loader is inside the Process scope and the Loader
namespace is at global scope, but it's still confusing to read.
Fortunately, this shouldn't last for very long since the responsibility
for loading Processes is going to move to a fake OS object which will
expect to load a particular type of Process, for instance, fake 64 bit
x86 linux will load either 32 or 64 bit x86 processes.
That means that the capability to feed any binary that matches the
current build into gem5 and have gem5 figure out what to do with it
will likely be going away in the future. That's likely for the best,
since it will force users to be more explicit about what they're trying
to do, ie what OS they want to try to load a given binary, and also
will prevent loading two or more Processes which are for different OSes
to the same system, something that's possible today as far as I know
since there are no consistency checks.
Change-Id: Iea0012e98f39f5e20a7c351b78cdff9401f5e326
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24783
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The GuestABI used to call the system-calls infers the size of values
read from the registers based on the function signature of the system
call. For mmap this was causing offset to be truncated to a 32-bit
value. In the GPUComputeDriver mmap, the offset must be a 64-bit
value. This fixes a bug where the doorbell memory was not setup and
causing GPU applications to fail.
Change-Id: I75d9b32c0470d1907c68826ef81cf6cd46f60ea7
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27367
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
This updates the syscalls for mmap, munmap, and mremap. The mmap
changes now create a virtual memory area through the MemState class
to allow for lazy allocation of mmapped regions. This provides
substantial performance boost for sparse usage of mmaps. The munmap
syscall is added to reclaim the virtual memory area reserved for the
mmapped region. The mremap syscall moves or resizes an mmapped region
and updates the corresponding virtual memory area region to keep the
page tables in sync.
Change-Id: Ide158e69cdff19bc81157e3e9826bcabc2a51140
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/26863
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
