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2018-02-01alpha: fix for no 'break' in the case statementSujay Phadke
gem5 won't compile correctly since g++ will throw a warning (error) that the next case statement below this one is reachable since there is no 'break' statement. Signed-off-by: Sujay Phadke Change-Id: Icab646ee5abcfeb6ba3e690909042927b4003eba Reviewed-on: https://gem5-review.googlesource.com/7521 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2018-01-23tarch, mem: Abstract the data stored in the SE page tables.Gabe Black
Rather than store the actual TLB entry that corresponds to a mapping, we can just store some abstracted information (address, a few flags) and then let the caller turn that into the appropriate entry. There could potentially be some small amount of overhead from creating entries vs. storing them and just installing them, but it's likely pretty minimal since that only happens on a TLB miss (ideally rare), and, if it is problematic, there could be some preallocated TLB entries which are just minimally filled in as necessary. This has the nice effect of finally making the page tables ISA agnostic. Change-Id: I11e630f60682f0a0029b0683eb8ff0135fbd4317 Reviewed-on: https://gem5-review.googlesource.com/7350 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-20arch, mem: Make the page table lookup function return a pointer.Gabe Black
This avoids having a copy in the lookup function itself, and the declaration of a lot of temporary TLB entry pointers in callers. The gpu TLB seems to have had the most dependence on the original signature of the lookup function, partially because it was relying on a somewhat unsafe copy to a TLB entry using a base class pointer type. Change-Id: I8b1cf494468163deee000002d243541657faf57f Reviewed-on: https://gem5-review.googlesource.com/7343 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-20sim, arch, base: Refactor the base remote GDB class.Gabe Black
Fold the GDBListener class into the main BaseRemoteGDB class, move around a bunch of functions, convert a lot of internal functions to be private, move some functions into the .cc, make some functions non-virtual which didn't really need to be overridden. Change-Id: Id0832b730b0fdfb2eababa5067e72c66de1c147d Reviewed-on: https://gem5-review.googlesource.com/7422 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-19arch, mem, sim: Consolidate and rename the SE mode page table classes.Gabe Black
Now that Nothing inherits from PageTableBase directly, it can be merged into FuncPageTable. This change also takes the opportunity to rename the combined class to EmulationPageTable which lets you know that it's specifically for SE mode. Also remove the page table entry cache since it doesn't seem to actually improve performance. The TLBs likely absorb the majority of the locality, essentially acting like a cache like they would in real hardware. Change-Id: If1bcb91aed08686603bf7bee37298c0eee826e13 Reviewed-on: https://gem5-review.googlesource.com/7342 Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-15arch: Fix a fatal_if in most of the arch's process classes.Gabe Black
When switching an assert to a fatal while addressing recent review feedback, I forgot to reverse the polarity of the condition, making the fatal fire in exactly the opposite of the conditions it was meant to. Change-Id: Icf49864ef449052bbb0d427dca786006166575c4 Reviewed-on: https://gem5-review.googlesource.com/7381 Reviewed-by: Matthias Jung <jungma@eit.uni-kl.de> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2018-01-11arch,mem: Remove the default value for page size.Gabe Black
This breaks one more architecture dependence outside of the ISAs. Change-Id: I071f9ed73aef78e1cd1752247c183e30854b2d28 Reviewed-on: https://gem5-review.googlesource.com/6982 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com>
2018-01-11arch,mem: Move page table construction into the arch classes.Gabe Black
This gets rid of an awkward NoArchPageTable class, and also gives the arch a place to inject ISA specific parameters (specifically page size) without having to have TheISA:: in the generic version of these types. Change-Id: I1412f303460d5c43dafdb9b3cd07af81c908a441 Reviewed-on: https://gem5-review.googlesource.com/6981 Reviewed-by: Alexandru Duțu <alexandru.dutu@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2018-01-10alpha,arm,mips,power,riscv,sparc,x86,cpu: Get rid of ISA_HAS_DELAY_SLOT.Gabe Black
This constant is, first, a #define, and second only used in one place. In that one place, it appears that the code it guards is no longer necessary in general. It was originally written to avoid refetching a block of data that you're still in, even if you've moved slightly farther in it because you're skipping the next instruction due to an annulled branch delay slot. In reality however, in SPARC, the one ISA I'm aware of which has this sort of branching behavior, the PC state object will correctly determine that no branch is happening in these cases. Code lower down in the loop will then recompute where fetching should continue based on the next PC, automatically skipping the annulled branch slot without misinterpretting the gap as a branch. This change therefore also removes this block of code. Change-Id: I820ebc9df10aeb4fcb69c12f6a784e9ec616743c Reviewed-on: https://gem5-review.googlesource.com/6821 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-12-23alpha,arm,mips,power,riscv,sparc,x86: Get rid of TheISA::NoopMachInst.Gabe Black
It's no longer used. Change-Id: I4a71bcb214f1bb186b92ef50841eca635e6701c5 Reviewed-on: https://gem5-review.googlesource.com/6826 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2017-12-22arch,cpu: "virtualize" the TLB interface.Gabe Black
CPUs have historically instantiated the architecture specific version of the TLBs to avoid a virtual function call, making them a little bit more dependent on what the current ISA is. Some simple performance measurement, the x86 twolf regression on the atomic CPU, shows that there isn't actually any performance benefit, and if anything the simulator goes slightly faster (although still within margin of error) when the TLB functions are virtual. This change switches everything outside of the architectures themselves to use the generic BaseTLB type, and then inside the ISA for them to cast that to their architecture specific type to call into architecture specific interfaces. The ARM TLB needed the most adjustment since it was using non-standard translation function signatures. Specifically, they all took an extra "type" parameter which defaulted to normal, and translateTiming returned a Fault. translateTiming actually doesn't need to return a Fault because everywhere that consumed it just stored it into a structure which it then deleted(?), and the fault is stored in the Translation object when the translation is done. A little more work is needed to fully obviate the arch/tlb.hh header, so the TheISA::TLB type is still visible outside of the ISAs. Specifically, the TlbEntry type is used in the generic PageTable which lives in src/mem. Change-Id: I51b68ee74411f9af778317eff222f9349d2ed575 Reviewed-on: https://gem5-review.googlesource.com/6921 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-12-13cpu,alpha,mips,power,riscv,sparc: Get rid of eaComp and memAccInst.Gabe Black
Neither of these were used, particularly memAccInst. Change-Id: I4ac9e44cf624e5de42519d586d7b699f08a2cdfc Reviewed-on: https://gem5-review.googlesource.com/6601 Maintainer: Gabe Black <gabeblack@google.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
2017-12-04misc: Rename misc.(hh|cc) to logging.(hh|cc)Gabe Black
These files aren't a collection of miscellaneous stuff, they're the definition of the Logger interface, and a few utility macros for calling into that interface (panic, warn, etc.). Change-Id: I84267ac3f45896a83c0ef027f8f19c5e9a5667d1 Reviewed-on: https://gem5-review.googlesource.com/6226 Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2017-11-07alpha,arm,mips,power,riscv,sparc,x86: Merge exec decl templates.Gabe Black
In the ISA instruction definitions, some classes were declared with execute, etc., functions outside of the main template because they had CPU specific signatures and would need to be duplicated with each CPU plugged into them. Now that the instructions always just use an ExecContext, there's no reason for those templates to be separate. This change folds those templates together. Change-Id: I13bda247d3d1cc07c0ea06968e48aa5b4aace7fa Reviewed-on: https://gem5-review.googlesource.com/5401 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Alec Roelke <ar4jc@virginia.edu> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-11-02alpha,arm,mips,power,riscv,sparc,x86,isa: De-specialize ExecContexts.Gabe Black
The ISA parser used to generate different copies of exec functions for each exec context class a particular CPU wanted to use. That's since been changed so that those functions take a pointer to the base ExecContext, so the code which would generate those extra functions can be removed, and some functions which used to be templated on an ExecContext subclass can be untemplated, or minimally less templated. Now that some functions aren't going to be instantiated multiple times with different signatures, there are also opportunities to collapse templates and make many instruction definitions simpler within the parser. Since those changes will be less mechanical, they're left for later changes and will probably be done in smaller increments. Change-Id: I0015307bb02dfb9c60380b56d2a820f12169ebea Reviewed-on: https://gem5-review.googlesource.com/5381 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-10-17scons: Stop generating inc.d in the isa parser.Gabe Black
Generating dependency/build product information in the isa parser breaks scons idea of how a build is supposed to work. Arm twisting it into working forced a lot of false dependencies which slowed down the build. Change-Id: Iadee8c930fd7c80136d200d69870df7672a6b3ca Reviewed-on: https://gem5-review.googlesource.com/5081 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Gabe Black <gabeblack@google.com>
2017-10-13mem: Signal the local monitor when clearing the global monitorNikos Nikoleris
ARM systems require the coordination of the global and local monitors. When the system is run without caches the global monitor is implemented in the abstract memory object. This change adds a callback from the abstract memory that notifies the local monitor when the global monitor is cleared. Additionally, for ARM systems the local monitor signals the event register and wakes the thread context up. Subsequent wait-for-event (WFE) instructions will be immediately signaled. Change-Id: If6c038f3a6bea7239ba4258f07f39c7f9a30500b Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/3760 Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2017-09-21alpha: Move some initialization logic from loadState into unserialize.Gabe Black
The primary difference between loadState and unserialize, at least when eventually using the default SimObject implementation of loadState, is that unserialize is called only if there's a corresponding section in the checkpoint being restored. In this particular case, the AlphaProcess class calls the generic Process unserialize function, and that does other critical initialization like set up the processes page table. If the unserialize function isn't called, other serious problems would break the simulation anyway. This removes the final custom implementation of loadState. Change-Id: If50062392196bd37efd5ba04fd7aee6907b00dc6 Reviewed-on: https://gem5-review.googlesource.com/4741 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-09-11stats: Move the swpipl function into the Alpha kernel stats.Gabe Black
This stat is only incremented by Alpha. Also move the _hwrei into the Alpha stats object since it's the class that actually sets up and maintains that value and it probably should have been there all along. Change-Id: Ibd038a33230c01432c160490926d8e1e55f8ccb0 Reviewed-on: https://gem5-review.googlesource.com/4601 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2017-09-11stats: Get rid of some kernel stats related cruft.Gabe Black
The kernel stat mechanism should really be refactored and moved somewhere else, but in the mean time there's some old cruft that can be cleared away. Change-Id: I21e725de590dda0d20bf3bc675bbe976c7b1bd86 Reviewed-on: https://gem5-review.googlesource.com/4600 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-08-30arch-alpha: Add missing overridesAndreas Sandberg
Change-Id: I3a52fcdb449c7df1612466270aa2c9b0a0f3afef Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-on: https://gem5-review.googlesource.com/4281 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-07-05arch: ISA parser additions of vector registersRekai Gonzalez-Alberquilla
Reiley's update :) of the isa parser definitions. My addition of the vector element operand concept for the ISA parser. Nathanael's modification creating a hierarchy between vector registers and its constituencies to the isa parser. Some fixes/updates on top to consider instructions as vectors instead of floating when they use the VectorRF. Some counters added to all the models to keep faithful counts. Change-Id: Id8f162a525240dfd7ba884c5a4d9fa69f4050101 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2706 Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-07-05cpu: Added interface for vector reg fileRekai Gonzalez-Alberquilla
This patch adds some more functionality to the cpu model and the arch to interface with the vector register file. This change consists mainly of augmenting ThreadContexts and ExecContexts with calls to get/set full vectors, underlying microarchitectural elements or lanes. Those are meant to interface with the vector register file. All classes that implement this interface also get an appropriate implementation. This requires implementing the vector register file for the different models using the VecRegContainer class. This change set also updates the Result abstraction to contemplate the possibility of having a vector as result. The changes also affect how the remote_gdb connection works. There are some (nasty) side effects, such as the need to define dummy numPhysVecRegs parameter values for architectures that do not implement vector extensions. Nathanael Premillieu's work with an increasing number of fixes and improvements of mine. Change-Id: Iee65f4e8b03abfe1e94e6940a51b68d0977fd5bb Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> [ Fix RISCV build issues and CC reg free list initialisation ] Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2705
2017-07-05cpu: Simplify the rename interface and use RegIdRekai Gonzalez-Alberquilla
With the hierarchical RegId there are a lot of functions that are redundant now. The idea behind the simplification is that instead of having the regId, telling which kind of register read/write/rename/lookup/etc. and then the function panic_if'ing if the regId is not of the appropriate type, we provide an interface that decides what kind of register to read depending on the register type of the given regId. Change-Id: I7d52e9e21fc01205ae365d86921a4ceb67a57178 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> [ Fix RISCV build issues ] Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2702
2017-07-05arch, cpu: Architectural Register structural indexingNathanael Premillieu
Replace the unified register mapping with a structure associating a class and an index. It is now much easier to know which class of register the index is referring to. Also, when adding a new class there is no need to modify existing ones. Change-Id: I55b3ac80763702aa2cd3ed2cbff0a75ef7620373 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> [ Fix RISCV build issues ] Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/2700
2017-05-18base: Refactor the GDB code.Gabe Black
The new version modularizes the implementation of the various commands, gets rid of dynamic allocation of the register cache, fixes some small style problems, and uses exceptions to simplify error handling internal to the GDB stub. Change-Id: Iff3548373ce4adfb99106a810f5713b769df89b2 Reviewed-on: https://gem5-review.googlesource.com/3280 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Boris Shingarov <shingarov@gmail.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-03-09syscall-emul: Move memState into its own fileBrandon Potter
The Process class is full of implementation details and structures related to SE Mode. This changeset factors out an internal class from Process and moves it into a separate file. The purpose behind doing this is to clean up the code and make it a bit more modular. Change-Id: Ic6941a1657751e8d51d5b6b1dcc04f1195884280 Reviewed-on: https://gem5-review.googlesource.com/2263 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2017-02-27syscall_emul: [PATCH 15/22] add clone/execve for threading and multiprocess ↵Brandon Potter
simulations Modifies the clone system call and adds execve system call. Requires allowing processes to steal thread contexts from other processes in the same system object and the ability to detach pieces of process state (such as MemState) to allow dynamic sharing.
2015-07-20syscall_emul: [patch 13/22] add system call retry capabilityBrandon Potter
This changeset adds functionality that allows system calls to retry without affecting thread context state such as the program counter or register values for the associated thread context (when system calls return with a retry fault). This functionality is needed to solve problems with blocking system calls in multi-process or multi-threaded simulations where information is passed between processes/threads. Blocking system calls can cause deadlock because the simulator itself is single threaded. There is only a single thread servicing the event queue which can cause deadlock if the thread hits a blocking system call instruction. To illustrate the problem, consider two processes using the producer/consumer sharing model. The processes can use file descriptors and the read and write calls to pass information to one another. If the consumer calls the blocking read system call before the producer has produced anything, the call will block the event queue (while executing the system call instruction) and deadlock the simulation. The solution implemented in this changeset is to recognize that the system calls will block and then generate a special retry fault. The fault will be sent back up through the function call chain until it is exposed to the cpu model's pipeline where the fault becomes visible. The fault will trigger the cpu model to replay the instruction at a future tick where the call has a chance to succeed without actually going into a blocking state. In subsequent patches, we recognize that a syscall will block by calling a non-blocking poll (from inside the system call implementation) and checking for events. When events show up during the poll, it signifies that the call would not have blocked and the syscall is allowed to proceed (calling an underlying host system call if necessary). If no events are returned from the poll, we generate the fault and try the instruction for the thread context at a distant tick. Note that retrying every tick is not efficient. As an aside, the simulator has some multi-threading support for the event queue, but it is not used by default and needs work. Even if the event queue was completely multi-threaded, meaning that there is a hardware thread on the host servicing a single simulator thread contexts with a 1:1 mapping between them, it's still possible to run into deadlock due to the event queue barriers on quantum boundaries. The solution of replaying at a later tick is the simplest solution and solves the problem generally.
2016-11-09syscall_emul: [patch 8/22] refactor process classBrandon Potter
Moves aux_vector into its own .hh and .cc files just to get it out of the already crowded Process files. Arguably, it could stay there, but it's probably better just to move it and give it files. The changeset looks ugly around the Process header file, but the goal here is to move methods and members around so that they're not defined randomly throughout the entire header file. I expect this is likely one of the reasons why I several unused variables related to this class. So, the methods are declared first followed by members. I've tried to aggregate them together so that similar entries reside near one another. There are other changes coming to this code so this is by no means the final product.
2016-11-09syscall_emul: [patch 5/22] remove LiveProcess class and use Process insteadBrandon Potter
The EIOProcess class was removed recently and it was the only other class which derived from Process. Since every Process invocation is also a LiveProcess invocation, it makes sense to simplify the organization by combining the fields from LiveProcess into Process.
2016-11-09syscall_emul: [patch 4/22] remove redundant M5_pid field from processBrandon Potter
2016-11-09style: [patch 3/22] reduce include dependencies in some headersBrandon Potter
Used cppclean to help identify useless includes and removed them. This involved erroneously included headers, but also cases where forward declarations could have been used rather than a full include.
2016-11-09syscall_emul: [patch 2/22] move SyscallDesc into its own .hh and .ccBrandon Potter
The class was crammed into syscall_emul.hh which has tons of forward declarations and template definitions. To clean it up a bit, moved the class into separate files and commented the class with doxygen style comments. Also, provided some encapsulation by adding some accessors and a mutator. The syscallreturn.hh file was renamed syscall_return.hh to make it consistent with other similarly named files in the src/sim directory. The DPRINTF_SYSCALL macro was moved into its own header file with the include the Base and Verbose flags as well. --HG-- rename : src/sim/syscallreturn.hh => src/sim/syscall_return.hh
2016-11-09style: [patch 1/22] use /r/3648/ to reorganize includesBrandon Potter
2016-11-17alpha: Remove ALPHA tru64 support and associated testsAndreas Hansson
No one appears to be using it, and it is causing build issues and increases the development and maintenance effort.
2016-07-21isa: Modify get/check interrupt routinesMitch Hayenga
Make it so that getInterrupt *always* returns an interrupt if checkInterrupts() returns true. This fixes/simplifies handling of interrupts on the SMT FS CPUs (currently minor).
2016-06-06stats: Fixing regStats function for some SimObjectsDavid Guillen Fandos
Fixing an issue with regStats not calling the parent class method for most SimObjects in Gem5. This causes issues if one adds new stats in the base class (since they are never initialized properly!). Change-Id: Iebc5aa66f58816ef4295dc8e48a357558d76a77c Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
2016-04-07Revert to 74c1e6513bd0 (sim: Thermal support for Linux)Andreas Sandberg
2014-11-18power: Add power states to ClockedObjectAkash Bagdia
Add 4 power states to the ClockedObject, provides necessary access functions to check and update the power state. Default power state is UNDEFINED, it is responsibility of the respective simulation model to provide the startup state and any other logic for state change. Add number of transition stat. Add distribution of time spent in clock gated state. Add power state residency stat. Add dump call back function to allow stats update of distribution and residency stats.
2016-04-01syscall_emul: remove mmapFlagTableSteve Reinhardt
After all this it turns out we don't even use it.
2016-04-01syscall_emul: factor out flag tables into common fileSteve Reinhardt
The openFlagTable and mmapFlagTables for emulated Linux platforms are basically identical, but are specified repetitively for every platform. Use a common file that gets included for each platform so that we only have one copy, making them more consistent and simplifying changes (like adding #ifdefs). In the process, made some minor fixes that slipped through due to previous inconsistencies, and added more #ifdefs to try to fix building on alternative hosts.
2016-03-17base: support dynamic loading of Linux ELF objects in SE modeBrandon Potter
2016-03-17syscall_emul: move mmapGrowsDown() to LiveProcessSteve Reinhardt
The mmapGrowsDown() method was a static method on the OperatingSystem class (and derived classes), which worked OK for the templated syscall emulation methods, but made it hard to access elsewhere. This patch moves the method to be a virtual function on the LiveProcess method, where it can be overridden for specific platforms (for now, Alpha). This patch also changes the value of mmapGrowsDown() from being false by default and true only on X86Linux32 to being true by default and false only on Alpha, which seems closer to reality (though in reality most people use ASLR and this doesn't really matter anymore). In the process, also got rid of the unused mmap_start field on LiveProcess and OperatingSystem mmapGrowsUp variable.
2016-03-17syscall_emul: extend mmap system call to support file backed mmapsBrandon Potter
For O3, which has a stat that counts reg reads, there is an additional reg read per mmap() call since there's an arg we no longer ignore. Otherwise, stats should not be affected.
2016-03-17syscall_emul: add many Linux kernel flagsBrandon Potter
2016-03-17syscall_emul: rename OpenFlagTransTable structBrandon Potter
The structure definition only had the open system call flag set in mind when it was named, so we rename it here with the intention of using it to define additional tables to translate flags for other system calls in the future.
2016-02-06style: fix missing spaces in control statementsSteve Reinhardt
Result of running 'hg m5style --skip-all --fix-control -a'.
2016-02-06style: remove trailing whitespaceSteve Reinhardt
Result of running 'hg m5style --skip-all --fix-white -a'.
2016-01-17cpu. arch: add initiateMemRead() to ExecContext interfaceSteve Reinhardt
For historical reasons, the ExecContext interface had a single function, readMem(), that did two different things depending on whether the ExecContext supported atomic memory mode (i.e., AtomicSimpleCPU) or timing memory mode (all the other models). In the former case, it actually performed a memory read; in the latter case, it merely initiated a read access, and the read completion did not happen until later when a response packet arrived from the memory system. This led to some confusing things, including timing accesses being required to provide a pointer for the return data even though that pointer was only used in atomic mode. This patch splits this interface, adding a new initiateMemRead() function to the ExecContext interface to replace the timing-mode use of readMem(). For consistency and clarity, the readMemTiming() helper function in the ISA definitions is renamed to initiateMemRead() as well. For x86, where the access size is passed in explicitly, we can also get rid of the data parameter at this level. For other ISAs, where the access size is determined from the type of the data parameter, we have to keep the parameter for that purpose.