summaryrefslogtreecommitdiff
path: root/src/cpu
AgeCommit message (Collapse)Author
2019-05-28cpu: Remove assert causing issues with x86 Linux bootGiacomo Gabrielli
Change-Id: I5e0b189ced0dd59ac6dbbb2c498c068e132b9b93 Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18910 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-18arch, base, cpu, dev, mem, sim: Remove #if 0-ed out code.Gabe Black
This code will be preserved through version control, but otherwise creates clutter and will rot in place since it's never compiled. Change-Id: Id265f6deac445116843956ea5cf1210d8127274e Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18608 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-14Revert "cpu: fix how a thread starts up in MinorCPU"Giacomo Travaglini
This reverts commit 02dafc5498750d9734ba8f2a1608a846f90b71d1. The commit was part of a patchset which broke MinorCPU regressions (switcheroo) Change-Id: I0a8098fc71abe5838014e587dbe372b258d8aa9f Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18604 Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-14Revert "cpu: stop scheduling suspended threads in MinorCPU"Giacomo Travaglini
This reverts commit 6a6668bbc4b038b98eb3ee64ffb034719316afd9. The commit was part of a patchset which broke MinorCPU regressions (switcheroo) Change-Id: I3c16a6478ba44b9d27cdd3d64a710a356999df05 Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18603 Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-14Revert "cpu: fix branching when thread is suspended in MinorCPU"Giacomo Travaglini
This reverts commit e437086341712f1435db655b3527ea29b3311f4e. The commit was part of a patchset which broke MinorCPU regressions (switcheroo) Change-Id: Ib8482034c2402008ccfa552325a8eb31e731b619 Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18602 Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-14base: Move SatCounter to base directoryDaniel
Saturating counters are used by many objects, not only the cpu predictors. Therefore, move the class to the base folder so that it can be more easily used. Change-Id: I26f799324bdd8720ab8834c72a2002149cee777c Signed-off-by: Daniel <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17993 Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2019-05-14cpu: Revamp saturating countersDaniel
Revamp the SatCounter class, improving comments, implementing increment, decrement and read operators to solve an old todo, and adding missing error checking. Change-Id: Ia057c423c90652ebd966b6b91a3471b17800f933 Signed-off-by: Daniel <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17992 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-13cpu: Make the indirect predictor into a SimObjectJairo Balart
Change-Id: Ice6549773def7d3e944fae450d4a079bc351e2ba Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/15319 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-05-11cpu,mem: Add support for partial loads/stores and wide mem. accessesGiacomo Gabrielli
This changeset adds support for partial (or masked) loads/stores, i.e. loads/stores that can disable accesses to individual bytes within the target address range. In addition, this changeset extends the code to crack memory accesses across most CPU models (TimingSimpleCPU still TBD), so that arbitrarily wide memory accesses are supported. These changes are required for supporting ISAs with wide vectors. Additional authors: - Gabor Dozsa <gabor.dozsa@arm.com> - Tiago Muck <tiago.muck@arm.com> Change-Id: Ibad33541c258ad72925c0b1d5abc3e5e8bf92d92 Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/13518 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-05-11cpu: Add a memory access predicateGiacomo Gabrielli
This changeset introduces a new predicate to guard memory accesses. The most immediate use for this is to allow proper handling of predicated-false vector contiguous loads and predicated-false micro-ops of vector gather loads (added in separate changesets). Change-Id: Ice6894fe150faec2f2f7ab796a00c99ac843810a Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17991 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Bradley Wang <radwang@ucdavis.edu> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Maintainer: Nikos Nikoleris <nikos.nikoleris@arm.com>
2019-04-30cpu: alpha: Delete all occurrances of the simPalCheck function.Gabe Black
This is now handled within the ISA description. Change-Id: Ie409bb46d102e59d4eb41408d9196fe235626d32 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18434 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-04-30cpu: Remove hwrei from the generic interfaces.Gabe Black
This mechanism is specific to Alpha and doesn't belong sprinkled around the CPU's generic mechanisms. Change-Id: I87904d1a08df2b03eb770205e2c4b94db25201a1 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18432 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-04-30arch: cpu: Track kernel stats using the base ISA agnostic type.Gabe Black
Then cast to the ISA specific type when necessary. This removes (mostly) an ISA specific aspect to some of the interfaces. The ISA specific version of the kernel stats still needs to be constructed and stored in a few places which means that kernel_stats.hh still needs to be a switching arch header, for instance. In the future, I'd like to make the kernel its own object like the Process objects in SE mode, and then it would be able to instantiate and maintain its own stats. Change-Id: I8309d49019124f6bea1482aaea5b5b34e8c97433 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18429 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-04-29cpu: Get rid of the (read|set)RegOtherThread methods.Gabe Black
These are implemented by MIPS internally now. Change-Id: If7465e1666e51e1314968efb56a5a814e62ee2d1 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18436 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-04-29cpu: Include debug flags regardless of whether the ISA is null.Gabe Black
Whether debug flags are available has no interaction with what the ISA is. Change-Id: I71d9204f948618831796e6c7a4c16bbebfb1a4fb Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18428 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-04-28mem: Minimize the use of MemObject.Gabe Black
MemObject doesn't provide anything beyond its base ClockedObject any more, so this change removes it from most inheritance hierarchies. Occasionally MemObject is replaced with SimObject when I was fairly confident that the extra functionality of ClockedObject wasn't needed. Change-Id: Ic014ab61e56402e62548e8c831eb16e26523fdce Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18289 Tested-by: kokoro <noreply+kokoro@google.com> Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Maintainer: Gabe Black <gabeblack@google.com>
2019-04-24cpu,mem: missing override specifierAndrea Mondelli
Change-Id: I731d3ef021596450ac307461f215760a148bb28a Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18348 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-04-22cpu: Eliminate the ProxyThreadContext class.Gabe Black
Replace it with direct inheritance from the ThreadContext class in the SimpleThread class which was the only place it was used. Also take the opportunity to use some specialized types instead of ints, etc., add some consts, and fix some style issues. Change-Id: I5d2cfa87b20dc43615e33e6755c9d016564e9c0e Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18048 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Maintainer: Gabe Black <gabeblack@google.com> Tested-by: kokoro <noreply+kokoro@google.com>
2019-04-10cpu: O3 switchFreeList checking VecElems instead of FloatRegsGiacomo Travaglini
Vector elements should be checked instead of floats since those are the ones mapped to the vector registers. Change-Id: I36088ab90e63720d846fcf5b43360da105b6c736 Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17850 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-04-05cpu: Correctly account for executed instructions in simple cpusNikos Nikoleris
Change-Id: I53f34b2d9db6e4d2e03dde42a970764bb2a5e701 Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17730 Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-04-03misc: Removed inconsistency in O3* debug msgsAndrea Mondelli
Added consistency in the DEBUG message form, to allow a better parsing. Fixed sn/tid type parameter. Removed some annoying newlines Change-Id: I4761c49fc12b874a7d8b46779475b606865cad4b Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17248 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-04-03arch-mips: added missing override specifier (o3)Andrea Mondelli
Change-Id: Ic538825a2964fd62def672b933a83067a15bd12a Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17648 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-03-28cpu: Added a probe to notify the address of retired instructionsJavier Bueno
A probe is added to notify the address of each retired instruction. Change-Id: Iefc1b09d74b3aa0aa5773b17ba637bf51f5a59c9 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17632 Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-03-27cpu: Fixed the indirect branch predictor GHR handlingPau Cabre
The internal indirect predictor global history was not being updated properly, resulting in higher than expected miss rates Also added a parameter to set the size of the indirect predictor GHR Change-Id: Ibc797816974cba6719da65122801e8919559a003 Signed-off-by: Pau Cabre <pau.cabre@metempsy.com> Reported-by: Daniel Carvalho <odanrc@yahoo.com.br> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/16928 Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br> Reviewed-by: Andrea Mondelli <Andrea.Mondelli@ucf.edu> Reviewed-by: Sudhanshu Jha <sudhanshu.jha@arm.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-03-23misc: missing override specifierAndrea Mondelli
Missing specifier of overridden virtual function declared in sim_object.hh Removed redundant "virtual" keyword Change-Id: I42aa3349b537c9e62607bce20cf1b3aabdb99bf2 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17468 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>
2019-03-21cpu-kvm: Added informative error messageRyan Gambord
PerfKvmCounter::attach fails if the user doesn't have privileges to make the perf_event_open syscall. This is the default privilege setting since kernel 4.6. I've seen some users in the mailing list resort to running as root; changing the perf_event_paranoid setting is an alternative. Change-Id: I2bc6f76abb6e97bf34b408a611f64b1910f50a43 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17508 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-03-19arch, cpu, dev, gpu, mem, sim, python: start using getPort.Gabe Black
Replace the getMasterPort, getSlavePort, and getEthPort functions with getPort, and remove extraneous mechanisms that are no longer necessary. Change-Id: Iab7e3c02d2f3a0cf33e7e824e18c28646b5bc318 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17040 Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-03-14cpu: Refactor of Physical Register implementationAndrea Mondelli
The implementation of the PhyRegId class is shared between multiple cpu models. The o3/misc.hh should only be included in o3 models. This patch removes the dependencies between different model implementations, allowing to add new O3-like CPU model. Change-Id: Ibb812517043befe75c48fab3ce9605a0d272870b Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/16908 Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Reviewed-by: Bradley Wang <radwang@ucdavis.edu> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-03-14arch-arm,cpu: Add initial support for Arm SVEGiacomo Gabrielli
This changeset adds initial support for the Arm Scalable Vector Extension (SVE) by implementing: - support for most data-processing instructions (no loads/stores yet); - basic system-level support. Additional authors: - Javier Setoain <javier.setoain@arm.com> - Gabor Dozsa <gabor.dozsa@arm.com> - Giacomo Travaglini <giacomo.travaglini@arm.com> Thanks to Pau Cabre for his contribution of bugfixes. Change-Id: I1808b5ff55b401777eeb9b99c9a1129e0d527709 Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/13515 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-03-01mem-cache: alias to mem::getMasterPort in TLB classAndrea Mondelli
TLB:getMasterPort is used to obtain the PageWalkMasterPort if present and hides the BaseTLB::getMasterPort(). The TLB::getMasterPort() is renamed according to the expected behavior. Change-Id: If4f61189094a706d59805cd10f4f814e5830eda8 Reviewed-on: https://gem5-review.googlesource.com/c/16648 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-02-27misc: Segmentation Fault during O3PipeView executionAndrea Mondelli
During the O3PipeView execution, a potential invalid iterator is used to Update the instruction storeTick field. If the store_idx iterator is the first() of the StoreQueue, the corresponding instruction is removed from the queue, leaving the iterator invalid and not usable in the TRACING_ON block. This patch uses the store_inst variable to access (and update) the instruction tick, instead of the (potential) invalid one. Change-Id: I671052ef282b9048e5239da8629b89e8afa86bf0 Reviewed-on: https://gem5-review.googlesource.com/c/16322 Maintainer: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2019-02-26cpu: Fix indirect branch history updatesSrikant Bharadwaj
Recent changes to indirect branch predictor interface accesses non-existent buffers even when indirect predictor is not in use. Change-Id: I0df9ac4d5f6f3cb63e4d1bd36949c27f7611eef6 Reviewed-on: https://gem5-review.googlesource.com/c/16668 Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>
2019-02-22python: Fix param -> int conversion issuesAndreas Sandberg
Python 3 doesn't convert params to integers automatically in range(). Add __index__ to CheckedInt to enable implicit conversions again. Add explicit conversions where necessary. Change-Id: I2de6c9906d3bb7616f12ada6728b9e4b1928511c Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/16000 Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-22cpu-o3: Add cache read ports limit to LSQGabor Dozsa
This change introduces cache read ports to limit the number of per-cycle loads. Previously only the number of per-cycle stores could be limited. Change-Id: I39bbd984056c5a696725ee2db462a55b2079e2d4 Signed-off-by: Gabor Dozsa <gabor.dozsa@arm.com> Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/13517 Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br> Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-02-22python: Make iterator handling Python 3 compatibleAndreas Sandberg
Many functions that used to return lists (e.g., dict.items()) now return iterators and their iterator counterparts (e.g., dict.iteritems()) have been removed. Switch calls to the Python 2.7 iterator methods to use the Python 3 equivalent and add explicit list conversions where necessary. Change-Id: I0c18114955af8f4932d81fb689a0adb939dafaba Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/15992 Reviewed-by: Juha Jäykkä <juha.jaykka@arm.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
2019-02-19cpu: Add ISA* getter in Thread interfaceGiacomo Gabrielli
This patch is adding a ISA* getter to the TC interface Change-Id: Ib8ddc5d8fdd44e782f50a2ad15878a6bcf931e58 Reviewed-on: https://gem5-review.googlesource.com/c/16462 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com> Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>
2019-02-15cpu: Fix fast build broken due to unused variableGiacomo Travaglini
This fixes fast build for commit 25dc765889d948693995cfa622f001aa94b5364b (fast build is striping out assertions) Change-Id: I9536ad58a3d85990b16a1f8c2515f6bf5d3acf71 Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/16463 Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-13cpu: Added 8KB and 64KB TAGE-SC-L branch predictorJavier Bueno
The original paper of the branch predictor can be found here: http://www.jilp.org/cbp2016/paper/AndreSeznecLimited.pdf Change-Id: I684863752407685adaacedebb699205c3559c528 Reviewed-on: https://gem5-review.googlesource.com/c/14855 Reviewed-by: Sudhanshu Jha <sudhanshu.jha@arm.com> Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-02-12python: Don't assume SimObjects live in the global namespaceAndreas Sandberg
The importer in Python 3 doesn't like the way we import SimObjects from the global namespace. Convert the existing SimObject declarations to import from m5.objects. As a side-effect, this makes these files consistent with configuration files. Change-Id: I11153502b430822130722839e1fa767b82a027aa Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-on: https://gem5-review.googlesource.com/c/15981 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
2019-02-08cpu: Proposal for changing the indirect branch predictor interfaceJairo Balart
Now the indirect branch predictor handles its own GHR instead of getting the one from the direction predictor. Also, now the commit method of the indirect predictor is called for every pending branch on an update, as the indirect predictors may want to update their interal structures/histories with the information of each branch. Change-Id: I7053fbea42a53960a3bc1ba32912cc99c160511e Reviewed-on: https://gem5-review.googlesource.com/c/15318 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-02-08cpu: support atomic memory request type with AtomicOpFunctorTuan Ta
This patch enables all 4 CPU models (AtomicSimpleCPU, TimingSimpleCPU, MinorCPU and DerivO3CPU) to issue atomic memory (AMO) requests to memory system. Atomic memory instruction is treated as a special store instruction in all CPU models. In simple CPUs, an AMO request with an associated AtomicOpFunctor is simply sent to L1 dcache. In MinorCPU, an AMO request bypasses store buffer and waits for any conflicting store request(s) currently in the store buffer to retire before the AMO request is sent to the cache. AMO requests are not buffered in the store buffer, so their effects appear immediately in the cache. In DerivO3CPU, an AMO request is inserted in the store buffer so that it is delivered to the cache only after all previous stores are issued to the cache. Data forwarding between between an outstanding AMO in the store buffer and a subsequent load is not allowed since the AMO request does not hold valid data until it's executed in the cache. This implementation assumes that a target ISA implementation must insert enough memory fences as micro-ops around an atomic instruction to enforce a correct order of memory instructions with respect to its memory consistency model. Without extra memory fences, this implementation can allow AMOs and other memory instructions that do not conflict (i.e., not target the same address) to reorder. This implementation also assumes that atomic instructions execute within a cache line boundary since the cache for now is not able to execute an operation on two different cache lines in one single step. Therefore, ISAs like x86 that require multi-cache-line atomic instructions need to either use a pair of locking load and unlocking store or change the cache implementation to guarantee the atomicity of an atomic instruction. Change-Id: Ib8a7c81868ac05b98d73afc7d16eb88486f8cf9a Reviewed-on: https://gem5-review.googlesource.com/c/8188 Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-08cpu: fix how branching is handled when a thread is suspended in MinorCPUTuan Ta
When a thread is suspended, all instructions after the suspension need to be discarded since the thread will take a different execution stream when it wakes up. To do that, in MinorCPU, whenever a thread gets suspended, we change the current execution stream by updating the current branch with BranchData::SuspendThread reason. Change-Id: I7cdcda22c1cf6e8ac8db8800b7d9ec052433fdf3 Reviewed-on: https://gem5-review.googlesource.com/c/9626 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@gmail.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-08cpu: stop scheduling suspended threads in all stages of MinorCPUTuan Ta
This patch makes suspended threads non-schedulable in Fetch1, Fetch2, Decode and Execute stages in MinorCPU. Change-Id: Ie79857e13b7b782d9c58c32310993a132b609cf9 Reviewed-on: https://gem5-review.googlesource.com/c/9625 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@gmail.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-08sim,cpu: make exit_group halt all threads in a groupTuan Ta
When a thread calls exit_group, in addition to halting the thread itself, it needs to halt all other threads in its group (i.e., threads sharing the same thread group ID). This patch enables threads to do that. Change-Id: Ib2e158fb27cf98843f177a64a2d643b1bbc94d03 Reviewed-on: https://gem5-review.googlesource.com/c/9623 Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-08cpu: fixed how O3 CPU executes an exit system callTuan Ta
When a thread executed an exit syscall in SE mode, the thread context was removed immediately in the same cycle, which left inflight squash operations and trap event incomplete. The problem happened when a new thread was assigned to the CPU later. The new thread started with some incomplete transactions of the previous thread (e.g., squashing). This problem could cause incorrect execution flow for the new thread (i.e., pc was not reset properly at the exit point), deadlock (i.e., some stage-to-stage signals were not reset) and incorrect rename map between logical and physical registers. This patch adds a new state called 'Halting' to the thread context and defers removing thread context from a CPU until a trap event initiated by an exit syscall execution is processed. This patch also makes sure that the removal of a thread context happens after all inflight transactions of the to-be-removed thread in the pipeline complete. Change-Id: If7ef1462fb8864e22b45371ee7ae67e2a5ad38b8 Reviewed-on: https://gem5-review.googlesource.com/c/8184 Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-06cpu: fix how a thread starts up in MinorCPUTuan Ta
When a thread is activated by another thread calling a clone system call, the child thread's context is initialized in the middle of the clone system call and before the context is fully initialized. Therefore, the child thread starts fetching an unitialized PC, which could lead to a page fault. This patch adds a pipeline wakeup event that is scheduled later in the cycle when the thread is activated. This event ensures that the first fetch only happens after the thread context is fully initialized (e.g., in case of clone syscall, it is when the parent thread copies its context over to the child thread). When a thread first starts or wakes up, input queue to the Fetch2 stage needs to be drained since the execution flow is likely to change and previously fetched instructions in the queue may no longer be in the correct flow. This patch dumps/drains all inputs in the input queue of a thread context in the Fetch2 stage when the associated thread wakes up. Change-Id: Iad970638e435858b7289cd471158cc0afdbbb0e5 Reviewed-on: https://gem5-review.googlesource.com/c/8182 Reviewed-by: Brandon Potter <Brandon.Potter@amd.com> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Brandon Potter <Brandon.Potter@amd.com>
2019-02-05misc: added missing override specifierAndrea Mondelli
Added missing specifier for various virtual functions. Change-Id: I4783e92d78789a9ae182fad79aadceafb00b2458 Reviewed-on: https://gem5-review.googlesource.com/c/16103 Reviewed-by: Hoa Nguyen <hoanguyen@ucdavis.edu> Reviewed-by: Jason Lowe-Power <jason@lowepower.com> Maintainer: Jason Lowe-Power <jason@lowepower.com>
2019-02-05cpu: Made the Loop Predictor a SimObjectJavier Bueno
The Loop Predictor implementation is now a SimObject so that other branch predictors can easily use it (including LTAGE, which is now using it). It has also been updated with the latest available loop predictor implementation from Andre Seznec: http://www.irisa.fr/alf/downloads/seznec/TAGE-GSC-IMLI.tar Change-Id: I60ad079a2c49b00a1f84d5cfd3611631883a4b57 Reviewed-on: https://gem5-review.googlesource.com/c/15775 Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-02-05cpu: Made TAGE a SimObject that can be used by other predictorsJairo Balart
The TAGE implementation is now a SimObject so that other branch predictors can easily use it. It has also been updated with the latest available TAGE implementation from Andre Seznec: http://www.irisa.fr/alf/downloads/seznec/TAGE-GSC-IMLI.tar Change-Id: I2251b8b2d7f94124f9955f52b917dc3b064f090e Reviewed-on: https://gem5-review.googlesource.com/c/15317 Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com> Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
2019-02-01cpu, arch: Replace the CCReg type with RegVal.Gabe Black
Most architectures weren't using the CCReg type, and in x86 and arm it was already a uint64_t. Change-Id: I0b3d5e690e6b31db6f2627f449c89bde0f6750a6 Reviewed-on: https://gem5-review.googlesource.com/c/14515 Reviewed-by: Gabe Black <gabeblack@google.com> Maintainer: Gabe Black <gabeblack@google.com>