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Bryce Lanham blanham Chicago, Illinois

blanham/liballoc 76

liballoc - a memory allocator for hobbyist operating systems

blanham/ChickeNES 18

A NES emulator written in C

blanham/ChickenOS 9

A small monolithic kernel OS. Rough around the edges, and still contains bits of code in the early startup stages taken from the OSDev wiki.

blanham/JChickeNES 4

Java NES emulator

blanham/ChickeNEMU 3

Library of wrapper functions for use in emulators

blanham/libunix 3

Libunix - a unix abstration for hobbyist operating systmes

blanham/ChickeNESplusplus 2

An NES emulator written in C++

blanham/amethyst 0

Data-oriented and data-driven game engine written in Rust

blanham/AsobiOtoko 0

An open source Gameboy Emulator (WIP).

blanham/barebones-toolchain 0

Barebones i686-elf / ARMv7-eabi cross-compiler & toolchain

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Peter Maydell

commit sha 9ac5df20f51fabcba0d902025df4bd7ea987c158

Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20200221-1' into staging target-arm queue: * aspeed/scu: Implement chip ID register * hw/misc/iotkit-secctl: Fix writing to 'PPC Interrupt Clear' register * mainstone: Make providing flash images non-mandatory * z2: Make providing flash images non-mandatory * Fix failures to flush SVE high bits after AdvSIMD INS/ZIP/UZP/TRN/TBL/TBX/EXT * Minor performance improvement: spend less time recalculating hflags values * Code cleanup to isar_feature function tests * Implement ARMv8.1-PMU and ARMv8.4-PMU extensions * Bugfix: correct handling of PMCR_EL0.LC bit * Bugfix: correct definition of PMCRDP * Correctly implement ACTLR2, HACTLR2 * allwinner: Wire up USB ports * Vectorize emulation of USHL, SSHL, PMUL* * xilinx_spips: Correct the number of dummy cycles for the FAST_READ_4 cmd * sh4: Fix PCI ISA IO memory subregion # gpg: Signature made Fri 21 Feb 2020 16:17:37 GMT # gpg: using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE # gpg: issuer "peter.maydell@linaro.org" # gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate] # gpg: aka "Peter Maydell <pmaydell@gmail.com>" [ultimate] # gpg: aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate] # Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83 15CF 3C25 25ED 1436 0CDE * remotes/pmaydell/tags/pull-target-arm-20200221-1: (46 commits) target/arm: Set MVFR0.FPSP for ARMv5 cpus target/arm: Use isar_feature_aa32_simd_r32 more places target/arm: Rename isar_feature_aa32_simd_r32 sh4: Fix PCI ISA IO memory subregion xilinx_spips: Correct the number of dummy cycles for the FAST_READ_4 cmd target/arm: Convert PMULL.8 to gvec target/arm: Convert PMULL.64 to gvec target/arm: Convert PMUL.8 to gvec target/arm: Vectorize USHL and SSHL arm: allwinner: Wire up USB ports hcd-ehci: Introduce "companion-enable" sysbus property hw: usb: hcd-ohci: Move OHCISysBusState and TYPE_SYSBUS_OHCI to include file target/arm: Correctly implement ACTLR2, HACTLR2 target/arm: Use FIELD_EX32 for testing 32-bit fields target/arm: Use isar_feature function for testing AA32HPD feature target/arm: Test correct register in aa32_pan and aa32_ats1e1 checks target/arm: Correct handling of PMCR_EL0.LC bit target/arm: Correct definition of PMCRDP target/arm: Provide ARMv8.4-PMU in '-cpu max' target/arm: Implement ARMv8.4-PMU extension ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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Peter Maydell

commit sha 88e2b97aa3e369a454c9d8360afddc348070c708

Merge remote-tracking branch 'remotes/dgilbert-gitlab/tags/pull-virtiofs-20200221' into staging virtiofs pull 20200221 Mostly minor cleanups. Miroslav's fixes a make install corner case. Philippe's set includes an error corner case fix. # gpg: Signature made Fri 21 Feb 2020 13:21:39 GMT # gpg: using RSA key 45F5C71B4A0CB7FB977A9FA90516331EBC5BFDE7 # gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>" [full] # Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A 9FA9 0516 331E BC5B FDE7 * remotes/dgilbert-gitlab/tags/pull-virtiofs-20200221: docs: Fix virtiofsd.1 location virtiofsd: Remove fuse.h and struct fuse_module tools/virtiofsd/fuse_lowlevel: Fix fuse_out_header::error value tools/virtiofsd/passthrough_ll: Remove unneeded variable assignment tools/virtiofsd/passthrough_ll: Remove unneeded variable assignment virtiofsd: Help message fix for 'seconds' Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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Denis Plotnikov

commit sha c9b7d9ec21dfca716f0bb3b68dee75660d86629c

virtio: increase virtqueue size for virtio-scsi and virtio-blk The goal is to reduce the amount of requests issued by a guest on 1M reads/writes. This rises the performance up to 4% on that kind of disk access pattern. The maximum chunk size to be used for the guest disk accessing is limited with seg_max parameter, which represents the max amount of pices in the scatter-geather list in one guest disk request. Since seg_max is virqueue_size dependent, increasing the virtqueue size increases seg_max, which, in turn, increases the maximum size of data to be read/write from a guest disk. More details in the original problem statment: https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg03721.html Suggested-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Denis Plotnikov <dplotnikov@virtuozzo.com> Message-id: 20200214074648.958-1-dplotnikov@virtuozzo.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Stefan Hajnoczi

commit sha f25c0b547916962d0b1be260b5b643287bea0851

aio-posix: avoid reacquiring rcu_read_lock() when polling The first rcu_read_lock/unlock() is expensive. Nested calls are cheap. This optimization increases IOPS from 73k to 162k with a Linux guest that has 2 virtio-blk,num-queues=1 and 99 virtio-blk,num-queues=32 devices. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20200218182708.914552-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Paolo Bonzini

commit sha 8c3570e33954d26675ec6fd224ede02763dfbd1d

rcu_queue: add QSLIST functions QSLIST is the only family of lists for which we do not have RCU-friendly accessors, add them. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 20200220103828.24525-1-pbonzini@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Stefan Hajnoczi

commit sha 8c6b0356b53977bcfdea5299db07884915425b0c

util/async: make bh_aio_poll() O(1) The ctx->first_bh list contains all created BHs, including those that are not scheduled. The list is iterated by the event loop and therefore has O(n) time complexity with respected to the number of created BHs. Rewrite BHs so that only scheduled or deleted BHs are enqueued. Only BHs that actually require action will be iterated. One semantic change is required: qemu_bh_delete() enqueues the BH and therefore invokes aio_notify(). The tests/test-aio.c:test_source_bh_delete_from_cb() test case assumed that g_main_context_iteration(NULL, false) returns false after qemu_bh_delete() but it now returns true for one iteration. Fix up the test case. This patch makes aio_compute_timeout() and aio_bh_poll() drop from a CPU profile reported by perf-top(1). Previously they combined to 9% CPU utilization when AioContext polling is commented out and the guest has 2 virtio-blk,num-queues=1 and 99 virtio-blk,num-queues=32 devices. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 20200221093951.1414693-1-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Stefan Hajnoczi

commit sha ff29ed3a331d0cd26bcd30f7cd6c0c96c7d44eed

aio-posix: fix use after leaving scope in aio_poll() epoll_handler is a stack variable and must not be accessed after it goes out of scope: if (aio_epoll_check_poll(ctx, pollfds, npfd, timeout)) { AioHandler epoll_handler; ... add_pollfd(&epoll_handler); ret = aio_epoll(ctx, pollfds, npfd, timeout); } ... ... /* if we have any readable fds, dispatch event */ if (ret > 0) { for (i = 0; i < npfd; i++) { nodes[i]->pfd.revents = pollfds[i].revents; } } nodes[0] is &epoll_handler, which has already gone out of scope. There is no need to use pollfds[] for epoll. We don't need an AioHandler for the epoll fd. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-2-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Stefan Hajnoczi

commit sha ca8c6b22754b0f17818b1d1910d31f0aa1a49cc7

aio-posix: don't pass ns timeout to epoll_wait() Don't pass the nanosecond timeout into epoll_wait(), which expects milliseconds. The epoll_wait() timeout value does not matter if qemu_poll_ns() determined that the poll fd is ready, but passing a value in the wrong units is still ugly. Pass a 0 timeout to epoll_wait() instead. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-3-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Stefan Hajnoczi

commit sha 195ed8cb365edeb0d0a70a2ffdeb7a073f9a8117

qemu/queue.h: add QLIST_SAFE_REMOVE() QLIST_REMOVE() assumes the element is in a list. It also leaves the element's linked list pointers dangling. Introduce a safe version of QLIST_REMOVE() and convert open-coded instances of this pattern. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-4-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Stefan Hajnoczi

commit sha 4749079ce033a94784cbe20a661abeac598ff057

aio-posix: make AioHandler deletion O(1) It is not necessary to scan all AioHandlers for deletion. Keep a list of deleted handlers instead of scanning the full list of all handlers. The AioHandler->deleted field can be dropped. Let's check if the handler has been inserted into the deleted list instead. Add a new QLIST_IS_INSERTED() API for this check. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-5-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Stefan Hajnoczi

commit sha 7391d34c3cca09c0bb0140275839c6619b86ec0f

aio-posix: make AioHandler dispatch O(1) with epoll File descriptor monitoring is O(1) with epoll(7), but aio_dispatch_handlers() still scans all AioHandlers instead of dispatching just those that are ready. This makes aio_poll() O(n) with respect to the total number of registered handlers. Add a local ready_list to aio_poll() so that each nested aio_poll() builds a list of handlers ready to be dispatched. Since file descriptor polling is level-triggered, nested aio_poll() calls also see fds that were ready in the parent but not yet dispatched. This guarantees that nested aio_poll() invocations will dispatch all fds, even those that became ready before the nested invocation. Since only handlers ready to be dispatched are placed onto the ready_list, the new aio_dispatch_ready_handlers() function provides O(1) dispatch. Note that AioContext polling is still O(n) and currently cannot be fully disabled. This still needs to be fixed before aio_poll() is fully O(1). Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Sergio Lopez <slp@redhat.com> Message-id: 20200214171712.541358-6-stefanha@redhat.com [Fix compilation error on macOS where there is no epoll(87). The aio_epoll() prototype was out of date and aio_add_ready_list() needed to be moved outside the ifdef. --Stefan] Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha bac068e0648c1f5c37f6a0a9423b8aa55e8c09c2

softmmu: move vl.c to softmmu/ Move vl.c to a separate directory, similar to linux-user/ Update the chechpatch and get_maintainer scripts, since they relied on /vl.c for top_of_tree checks. Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Message-id: 20200220041118.23264-2-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha 7b73386222626608f843ca4773426dce4ebcc73a

softmmu: split off vl.c:main() into main.c A program might rely on functions implemented in vl.c, but implement its own main(). By placing main into a separate source file, there are no complaints about duplicate main()s when linking against vl.o. For example, the virtual-device fuzzer uses a main() provided by libfuzzer, and needs to perform some initialization before running the softmmu initialization. Now, main simply calls three vl.c functions which handle the guest initialization, main loop and cleanup. Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Message-id: 20200220041118.23264-3-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha 46a07579ebb081493618bfa00ef8e241cd0dcc4f

module: check module wasn't already initialized The virtual-device fuzzer must initialize QOM, prior to running vl:qemu_init, so that it can use the qos_graph to identify the arguments required to initialize a guest for libqos-assisted fuzzing. This change prevents errors when vl:qemu_init tries to (re)initialize the previously initialized QOM module. Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-id: 20200220041118.23264-4-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha e785e50a5eb37e143bbe68b1693753b9bcfba005

fuzz: add FUZZ_TARGET module type Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Message-id: 20200220041118.23264-5-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha e731d083e34b4dbebf0870c137df4405e4ae8319

qtest: add qtest_server_send abstraction qtest_server_send is a function pointer specifying the handler used to transmit data to the qtest client. In the standard configuration, this calls the CharBackend handler, but now it is possible for other types of handlers, e.g direct-function calls if the qtest client and server exist within the same process (inproc) Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Acked-by: Thomas Huth <thuth@redhat.com> Message-id: 20200220041118.23264-6-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha 075334810b3c795c7120eecaf18945befbb816c6

libqtest: add a layer of abstraction to send/recv This makes it simple to swap the transport functions for qtest commands to and from the qtest client. For example, now it is possible to directly pass qtest commands to a server handler that exists within the same process, without the standard way of writing to a file descriptor. Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Message-id: 20200220041118.23264-7-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha ca5d464151c72695a960d0f493f2fe7c083e468f

libqtest: make bufwrite rely on the TransportOps When using qtest "in-process" communication, qtest_sendf directly calls a function in the server (qtest.c). Previously, bufwrite used socket_send, which bypasses the TransportOps enabling the call into qtest.c. This change replaces the socket_send calls with ops->send, maintaining the benefits of the direct socket_send call, while adding support for in-process qtest calls. Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Message-id: 20200220041118.23264-8-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha 0bd9aef89ba941b41773d9dbfa94433c2b7d00de

qtest: add in-process incoming command handler The handler allows a qtest client to send commands to the server by directly calling a function, rather than using a file/CharBackend Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Message-id: 20200220041118.23264-9-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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Alexander Bulekov

commit sha 39397a9a76eb02ad8a772f43446fdb3344093c35

libqos: rename i2c_send and i2c_recv The names i2c_send and i2c_recv collide with functions defined in hw/i2c/core.c. This causes an error when linking against libqos and softmmu simultaneously (for example when using qtest inproc). Rename the libqos functions to avoid this. Signed-off-by: Alexander Bulekov <alxndr@bu.edu> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Acked-by: Thomas Huth <thuth@redhat.com> Message-id: 20200220041118.23264-10-alxndr@bu.edu Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

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