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2023-03-09gdb, gdbserver, gdbsupport: fix whitespace issuesSimon Marchi1-3/+1
Replace spaces with tabs in a bunch of places. Change-Id: If0f87180f1d13028dc178e5a8af7882a067868b0
2023-01-17Avoid submitting empty tasks in parallel_for_eachTom Tromey1-0/+30
I found that parallel_for_each would submit empty tasks to the thread pool. For example, this can happen if the number of tasks is smaller than the number of available threads. In the DWARF reader, this resulted in the cooked index containing empty sub-indices. This patch arranges to instead shrink the result vector and process the trailing entries in the calling thread.
2023-01-01Update copyright year range in header of all files managed by GDBJoel Brobecker1-1/+1
This commit is the result of running the gdb/copyright.py script, which automated the update of the copyright year range for all source files managed by the GDB project to be updated to include year 2023.
2022-08-30gdbsupport: add wrapper around result_of and invoke_resultSimon Marchi1-5/+5
When building with Clang 14 (using gcc 12 libstdc++ headers), I get: CXX dwarf2/read.o In file included from /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:94: /home/simark/src/binutils-gdb/gdb/../gdbsupport/parallel-for.h:142:21: error: 'result_of<(lambda at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7124:5) (__gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>, __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>)>' is deprecated: use 'std::invoke_result' instead [-Werror,-Wdeprecated-declarations] = typename std::result_of<RangeFunction (RandomIt, RandomIt)>::type; ^ /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7122:14: note: in instantiation of function template specialization 'gdb::parallel_for_each<__gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>, (lambda at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7124:5)>' requested here = gdb::parallel_for_each (1, per_bfd->all_comp_units.begin (), ^ /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../include/c++/12.1.1/type_traits:2597:9: note: 'result_of<(lambda at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7124:5) (__gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>, __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>)>' has been explicitly marked deprecated here { } _GLIBCXX17_DEPRECATED_SUGGEST("std::invoke_result"); ^ /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../include/c++/12.1.1/x86_64-pc-linux-gnu/bits/c++config.h:120:45: note: expanded from macro '_GLIBCXX17_DEPRECATED_SUGGEST' # define _GLIBCXX17_DEPRECATED_SUGGEST(ALT) _GLIBCXX_DEPRECATED_SUGGEST(ALT) ^ /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../include/c++/12.1.1/x86_64-pc-linux-gnu/bits/c++config.h:96:19: note: expanded from macro '_GLIBCXX_DEPRECATED_SUGGEST' __attribute__ ((__deprecated__ ("use '" ALT "' instead"))) ^ It complains about the use of std::result_of, which is deprecated in C++17 and removed in C++20: https://en.cppreference.com/w/cpp/types/result_of Given we'll have to transition to std::invoke_result eventually, make a GDB wrapper to mimimc std::invoke_result, which uses std::invoke_result for C++ >= 17 and std::result_of otherwise. This way, it will be easy to remove the wrapper in the future, just replace gdb:: with std::. Tested by building with gcc 12 in -std=c++11 and -std=c++17 mode, and clang in -std=c++17 mode (I did not test fully with clang in -std=c++11 mode because there are other unrelated issues). Change-Id: I50debde0a3307a7bc67fcf8fceefda51860efc1d
2022-08-05[gdbsupport] Add task size parameter in parallel_for_eachTom de Vries1-22/+91
Add a task_size parameter to parallel_for_each, defaulting to nullptr, and use the task size to distribute similarly-sized chunks to the threads. Tested on x86_64-linux.
2022-07-21[gdbsupport] Fix type of parallel_for_each_debugTom de Vries1-1/+1
When I changed the initialization of parallel_for_each_debug from 0 to false, I forgot to change the type from int to bool. Fix this. Tested by rebuilding on x86_64-linux.
2022-07-18[gdbsupport] Improve thread scheduling in parallel_for_eachTom de Vries1-0/+8
When running a task using parallel_for_each, we get the following distribution: ... Parallel for: n_elements: 7271 Parallel for: minimum elements per thread: 10 Parallel for: elts_per_thread: 1817 Parallel for: elements on worker thread 0 : 1817 Parallel for: elements on worker thread 1 : 1817 Parallel for: elements on worker thread 2 : 1817 Parallel for: elements on worker thread 3 : 0 Parallel for: elements on main thread : 1820 ... Note that there are 4 active threads, and scheduling elts_per_thread on each of those handles 4 * 1817 == 7268, leaving 3 "left over" elements. These leftovers are currently handled in the main thread. That doesn't seem to matter much for this example, but for say 10 threads and 99 elements, you'd have 9 threads handling 9 elements and 1 thread handling 18 elements. Instead, distribute the left over elements over the worker threads, such that we have: ... Parallel for: elements on worker thread 0 : 1818 Parallel for: elements on worker thread 1 : 1818 Parallel for: elements on worker thread 2 : 1818 Parallel for: elements on worker thread 3 : 0 Parallel for: elements on main thread : 1817 ... Tested on x86_64-linux.
2022-07-18[gdbsupport] Add parallel_for_each_debugTom de Vries1-1/+23
Add a parallel_for_each_debug variable, set to false by default. With an a.out compiled from hello world, we get with parallel_for_each_debug == true: ... $ gdb -q -batch a.out -ex start ... Parallel for: n_elements: 7271 Parallel for: minimum elements per thread: 10 Parallel for: elts_per_thread: 1817 Parallel for: elements on worker thread 0 : 1817 Parallel for: elements on worker thread 1 : 1817 Parallel for: elements on worker thread 2 : 1817 Parallel for: elements on worker thread 3 : 0 Parallel for: elements on main thread : 1820 Temporary breakpoint 1, main () at /home/vries/hello.c:6 6 printf ("hello\n"); ... Tested on x86_64-linux.
2022-07-14[gdbsupport] Add sequential_for_eachTom de Vries1-0/+23
Add a sequential_for_each alongside the parallel_for_each, which can be used as a drop-in replacement. This can be useful when debugging multi-threading behaviour, and you want to limit multi-threading in a fine-grained way. Tested on x86_64-linux, by using it instead of the parallel_for_each in dwarf2_build_psymtabs_hard.
2022-05-10Fix --disable-threading buildTom Tromey1-2/+2
PR build/29110 points out that GDB fails to build on mingw when the "win32" thread model is in use. It turns out that the Fedora cross tools using the "posix" thread model, which somehow manages to support std::future, whereas the win32 model does not. While looking into this, I found that the configuring with --disable-threading will also cause a build failure. This patch fixes this build by introducing a compatibility wrapper for std::future. I am not able to test the win32 thread model build, but I'm going to ask the reporter to try this patch. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29110
2022-04-12gdbsupport: use result_of_t instead of result_of in parallel-for.hSimon Marchi1-3/+3
When building with -std=c++11, I get: In file included from /home/smarchi/src/binutils-gdb/gdb/unittests/parallel-for-selftests.c:22: /home/smarchi/src/binutils-gdb/gdb/../gdbsupport/parallel-for.h:134:10: error: ‘result_of_t’ is not a member of ‘std’; did you mean ‘result_of’? 134 | std::result_of_t<RangeFunction (RandomIt, RandomIt)> | ^~~~~~~~~~~ | result_of This is because result_of_t has been introduced in C++14. Use the equivalent result_of<...>::type instead. result_of and result_of_t have been removed in C++20 though, so I think we'll need some patches eventually to make the code use invoke_result instead, depending on the C++ version. Change-Id: I4817f361c0ebcdd4b32976898fc368bb302b61b9
2022-04-12Return vector of results from parallel_for_eachTom Tromey1-25/+117
This changes gdb::parallel_for_each to return a vector of the results. However, if the passed-in function returns void, the return type remains 'void'. This functionality is used later, to parallelize the new indexer.
2022-04-12Add batching parameter to parallel_for_eachTom Tromey1-6/+12
parallel_for_each currently requires each thread to process at least 10 elements. However, when indexing, it's fine for a thread to handle just a single CU. This patch parameterizes this, and updates the one user.
2022-04-12Allow thread-pool.h to work without threadsTom Tromey1-7/+0
thread-pool.h requires CXX_STD_THREAD in order to even be included. However, there's no deep reason for this, and during review we found that one patch in the new DWARF indexer series unconditionally requires the thread pool. Because the thread pool already allows a task to be run in the calling thread (for example if it is configured to have no threads in the pool), it seemed straightforward to make this code ok to use when host threads aren't available at all. This patch implements this idea. I built it on a thread-less host (mingw, before my recent configure patch) and verified that the result builds. After the thread-pool change, parallel-for.h no longer needs any CXX_STD_THREAD checks at all, so this patch removes these as well.
2022-01-01Automatic Copyright Year update after running gdb/copyright.pyJoel Brobecker1-1/+1
This commit brings all the changes made by running gdb/copyright.py as per GDB's Start of New Year Procedure. For the avoidance of doubt, all changes in this commits were performed by the script.
2021-01-01Update copyright year range in all GDB filesJoel Brobecker1-1/+1
This commits the result of running gdb/copyright.py as per our Start of New Year procedure... gdb/ChangeLog Update copyright year range in copyright header of all GDB files.
2020-01-14Move gdbsupport to the top levelTom Tromey1-0/+86
This patch moves the gdbsupport directory to the top level. This is the next step in the ongoing project to move gdbserver to the top level. The bulk of this patch was created by "git mv gdb/gdbsupport gdbsupport". This patch then adds a build system to gdbsupport and wires it into the top level. Then it changes gdb to use the top-level build. gdbserver, on the other hand, is not yet changed. It still does its own build of gdbsupport. ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * src-release.sh (GDB_SUPPORT_DIRS): Add gdbsupport. * MAINTAINERS: Add gdbsupport. * configure: Rebuild. * configure.ac (configdirs): Add gdbsupport. * gdbsupport: New directory, move from gdb/gdbsupport. * Makefile.def (host_modules, dependencies): Add gnulib. * Makefile.in: Rebuild. gdb/ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * nat/x86-linux-dregs.c: Include configh.h. * nat/linux-ptrace.c: Include configh.h. * nat/linux-btrace.c: Include configh.h. * defs.h: Include config.h, bfd.h. * configure.ac: Don't source common.host. (CONFIG_OBS, CONFIG_SRCS): Remove gdbsupport files. * configure: Rebuild. * acinclude.m4: Update path. * Makefile.in (SUPPORT, LIBSUPPORT, INCSUPPORT): New variables. (CONFIG_SRC_SUBDIR): Remove gdbsupport. (INTERNAL_CFLAGS_BASE): Add INCSUPPORT. (CLIBS): Add LIBSUPPORT. (CDEPS): Likewise. (COMMON_SFILES): Remove gdbsupport files. (HFILES_NO_SRCDIR): Likewise. (stamp-version): Update path to create-version.sh. (ALLDEPFILES): Remove gdbsupport files. gdb/gdbserver/ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * server.h: Include config.h. * gdbreplay.c: Include config.h. * configure: Rebuild. * configure.ac: Don't source common.host. * acinclude.m4: Update path. * Makefile.in (INCSUPPORT): New variable. (INCLUDE_CFLAGS): Add INCSUPPORT. (SFILES): Update paths. (version-generated.c): Update path to create-version.sh. (gdbsupport/%-ipa.o, gdbsupport/%.o): Update paths. gdbsupport/ChangeLog 2020-01-14 Tom Tromey <tom@tromey.com> * common-defs.h: Add GDBSERVER case. Update includes. * acinclude.m4, aclocal.m4, config.in, configure, configure.ac, Makefile.am, Makefile.in, README: New files. * Moved from ../gdb/gdbsupport/ Change-Id: I07632e7798635c1bab389bf885971e584fb4bb78