| Message ID | 20240923-feature-build-info-cli-v2-1-66b3462f16a1@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] Add -build-info and -build-info-json CLI arguments | expand |
On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: > Add -build-info and -build-info-json CLI arguments for human and machine > readable output of build/compile-time configuration data. The source for > this data is the meson generated config-host.h. > > This information is mainly of interest to developers and other folk who > deal with many different builds of QEMU and need a way to properly > differentiate them. > > Because there's always the chance someone will want to consume an > interface programmatically, also add a -json option that does the same > but outputs a machine-readable JSON object. This turns our build system configuration information into a defacto public API, and while its using JSON, it isn't yusing QAPI. To some degree we leak our build system config names externally because the "if" stanzas in the QAPI schema get copied into the docs. Overall though I don't think we should be exposing this build config infomation externally. We've had many times, particularly with testing, where people have wanted to access CONFIG_XXX info about a QEMU binary, but IIRC we've always steered people towards querying for the actual feature they want, rather than looking at CONFIG_XXX settings. ie, look a query-audiodevs to discover what audio baxckends are built-in, don't look for CONFIG_XXX settings related to audio. If there are gaps in information we can query from QMP, we should aim to close those gaps. IOW, I don't think we should expose this build info info in either human readable or machine readable format. > > Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> > --- > Changes in v2: > - Fixed alignment of command and documentation in -h output. > - Link to v1: https://lore.kernel.org/r/20240923-feature-build-info-cli-v1-1-e8c42d845390@linaro.org > --- > Notes: > Sample output: > > $ ./qemu-system-aarch64 -build-info > ./qemu-system-aarch64 version 9.1.50 (v9.0.0-3444-g8d988656d8) build information > > configuration key key value > ----------------- --------- > accept4 > af_vsock > asan_iface_fiber > atomic64 > attr > audio_alsa > audio_drivers pa,sndio,oss > audio_oss > audio_pa > audio_pipewire > audio_sdl > audio_sndio > avx2_opt > avx512bw_opt > bdrv_ro_whitelist > bdrv_rw_whitelist > bindir /usr/local/bin > blkzoned > brlapi > capstone > clock_adjtime > close_range > coroutine_pool > cpuid_h > curl > curses > dbus_display > debug_graph_lock > debug_mutex > debug_tcg > dup3 > ebpf > epoll > epoll_create1 > eventfd > fallocate > fallocate_punch_hole > fallocate_zero_range > fdatasync > fdt > fiemap > fsfreeze > fstrim > fuse > fuse_lseek > gbm > getauxval > getcpu > getrandom > gettid > gio > gnutls > gnutls_crypto > gtk > hexagon_idef_parser > host_dsosuf .so > iasl /bin/iasl > inotify > inotify1 > int128 > int128_type > iovec > keyutils > kvm_targets i386-softmmu,x86_64-softmmu > l2tpv3 > libdw > libudev > linux > linux_io_uring > linux_magic_h > madvise > malloc_trim > memalign > memfd > opengl > open_by_handle > pixman > plugin > png > posix > posix_fallocate > posix_madvise > posix_memalign > ppoll > prctl_pr_set_timerslack > preadv > prefix /usr/local > pthread_affinity_np > pthread_setname_np_w_tid > qemu_confdir /usr/local/etc/qemu > qemu_datadir /usr/local/share/qemu > qemu_desktopdir /usr/local/share/applications > qemu_firmwarepath /usr/local/share/qemu-firmware > qemu_helperdir /usr/local/libexec > qemu_icondir /usr/local/share/icons > qemu_localedir /usr/local/share/locale > qemu_localstatedir /var/local > qemu_moddir /usr/local/lib/x86_64-linux-gnu/qemu > qom_cast_debug > relocatable > replication > rtnetlink > sdl > seccomp > seccomp_sysrawrc > secret_keyring > selinux > sendfile > setns > signalfd > slirp > smbd_command /usr/sbin/smbd > splice > statx > statx_mnt_id > syncfs > sync_file_range > sysconfdir /usr/local/etc > sysmacros > tasn1 > tcg 1 > timerfd > tls_priority NORMAL > tpm > trace_file trace > trace_log > usbfs > usb_libusb > valgrind_h > valloc > vduse_blk_export > vhost > vhost_crypto > vhost_kernel > vhost_net > vhost_net_user > vhost_net_vdpa > vhost_user > vhost_user_blk_server > vhost_vdpa > virtfs > vnc > vnc_jpeg > vte > x11 > xen_backend > xen_ctrl_interface_version 41700 > xkbcommon > zstd > blk_zone_rep_capacity > btrfs_h > copy_file_range > drm_h > fsxattr > getifaddrs > host_block_device > ipproto_mptcp > mlockall > openpty > pty_h > strchrnul > struct_stat_st_atim > system_function > utmpx > virgl_d3d_info_ext > host_x86_64 1 > qemu_version 9.1.50 > qemu_version_major 9 > qemu_version_micro 50 > qemu_version_minor 1 > > To: qemu-devel@nongnu.org > Cc: "Cleber Rosa" <crosa@redhat.com> > Cc: "Daniel P. Berrangé" <berrange@redhat.com> > Cc: "John Snow" <jsnow@redhat.com> > Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com> > Cc: "Paolo Bonzini" <pbonzini@redhat.com> > Cc: "Alex Bennée" <alex.bennee@linaro.org> > Cc: "Gustavo Romero" <gustavo.romero@linaro.org> > Cc: "Peter Maydell" <peter.maydell@linaro.org> > Cc: "Philippe Mathieu-Daudé" <philmd@linaro.org> > Cc: "Pierrick Bouvier" <pierrick.bouvier@linaro.org> > Cc: "Richard Henderson" <richard.henderson@linaro.org> > Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> > --- > meson.build | 15 +++++++- > qemu-options.hx | 15 ++++++++ > scripts/build_info_gen.py | 91 +++++++++++++++++++++++++++++++++++++++++++++++ > system/vl.c | 41 +++++++++++++++++++++ > 4 files changed, 161 insertions(+), 1 deletion(-) > > diff --git a/meson.build b/meson.build > index 10464466ff..eff2ee323a 100644 > --- a/meson.build > +++ b/meson.build > @@ -3292,7 +3292,20 @@ endif > # Generated sources # > ##################### > > -genh += configure_file(output: 'config-host.h', configuration: config_host_data) > +config_host_h = configure_file(output: 'config-host.h', configuration: config_host_data) > +genh += config_host_h > + > +build_info_h = custom_target('build-info.h', > + output: 'build-info.h', > + command: [ > + find_program('scripts/build_info_gen.py'), > + '--config-headers', > + config_host_h > + ], > + capture: true, > + build_by_default: true, > + build_always_stale: true) > +genh += build_info_h > > hxtool = find_program('scripts/hxtool') > shaderinclude = find_program('scripts/shaderinclude.py') > diff --git a/qemu-options.hx b/qemu-options.hx > index d94e2cbbae..6a32e0624f 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -24,6 +24,21 @@ SRST > Display version information and exit > ERST > > +DEF("build-info", 0, QEMU_OPTION_build_info, > + "-build-info display build information of executable and exit\n", QEMU_ARCH_ALL) > +SRST > +``-build-info`` > + Display build information of executable and exit > +ERST > + > +DEF("build-info-json", 0, QEMU_OPTION_build_info_json, > + "-build-info-json\n" > + " dump build information of executable in JSON format and exit\n", QEMU_ARCH_ALL) > +SRST > +``-build-info-json`` > + Dump build information of executable in JSON format and exit > +ERST > + > DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ > "-machine [type=]name[,prop[=value][,...]]\n" > " selects emulated machine ('-machine help' for list)\n" > diff --git a/scripts/build_info_gen.py b/scripts/build_info_gen.py > new file mode 100755 > index 0000000000..37a9421651 > --- /dev/null > +++ b/scripts/build_info_gen.py > @@ -0,0 +1,91 @@ > +#!/usr/bin/env python3 > + > +""" > +Generate build information header, build-info.h, > +for output of -build-info* command line arguments. > + > +SPDX-FileContributor: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> > +SPDX-FileCopyrightText: 2024 Linaro Ltd. > +SPDX-License-Identifier: GPL-2.0-or-later > +""" > + > +# Formatted with black --line-length 80 scripts/build-info-gen.py > + > +import argparse > +import logging > + > + > +def generate_key_val(header: str) -> str: > + # pylint: disable=missing-function-docstring > + > + with open(header, encoding="utf-8") as cfg: > + config = [l.split()[1:] for l in cfg if l.startswith("#define")] > + > + for cfg in config: > + if cfg[0].startswith("HAVE_"): > + yield (cfg[0].removeprefix("HAVE_").lower(), None) > + continue > + yield ( > + cfg[0].removeprefix("CONFIG_").lower(), > + ( > + cfg[1] > + if len(cfg) == 2 > + else "".join(cfg[1:]).replace('"', "") if len(cfg) > 2 else None > + ), > + ) > + > + > +def main() -> None: > + # pylint: disable=missing-function-docstring > + parser = argparse.ArgumentParser() > + parser.add_argument("-v", "--verbose", action="store_true") > + parser.add_argument( > + "--config-headers", > + metavar="CONFIG_HEADER", > + action="append", > + dest="config_headers", > + help="paths to configuration host C headers (*.h files)", > + required=False, > + default=[], > + ) > + args = parser.parse_args() > + if args.verbose: > + logging.basicConfig(level=logging.ERROR) > + logging.debug("args: %s", args) > + print( > + """// @generated by scripts/build-info-gen.py > + > +#include <stddef.h>""" > + ) > + print( > + """static struct build_info_t { > + const char *key; > + const char *value; > +} BUILD_INFO[] = {""" > + ) > + total = 0 > + header_width = 0 > + for header in args.config_headers: > + for key, val in generate_key_val(header): > + total += 1 > + header_width = max(header_width, len(key)) > + print( > + '{"', > + key, > + '", "', > + val.strip('"').strip(",").strip('"') if val else "", > + '"},', > + sep="", > + ) > + print("};") > + print("\nstatic size_t BUILD_INFO_SIZE = ", total, ";", sep="") > + print( > + "static unsigned int BUILD_INFO_HEADER_WIDTH = ", > + header_width, > + ";", > + sep="", > + ) > + > + > +if __name__ == "__main__": > + main() > diff --git a/system/vl.c b/system/vl.c > index fe547ca47c..5266b85d22 100644 > --- a/system/vl.c > +++ b/system/vl.c > @@ -908,6 +908,41 @@ static void help(int exitcode) > exit(exitcode); > } > > +static void build_info(const char *execname, bool as_json) > +{ > +#include "build-info.h" > + if (as_json) { > + printf("{\n"); > + for (size_t i = 0; i + 1 < BUILD_INFO_SIZE ; i++) { > + printf("\"%s\":\"%s\",\n", > + BUILD_INFO[i].key, > + BUILD_INFO[i].value); > + } > + if (BUILD_INFO_SIZE > 0) { > + printf("\"%s\":\"%s\"\n", > + BUILD_INFO[BUILD_INFO_SIZE - 1].key, > + BUILD_INFO[BUILD_INFO_SIZE - 1].value); > + } > + printf("}\n"); > + } else { > + printf("%s version " > + QEMU_FULL_VERSION > + " build information\n\n", execname ?:"QEMU"); > + printf(" %-*s key value\n", > + BUILD_INFO_HEADER_WIDTH, > + "configuration key"); > + printf(" %-*s ---------\n", > + BUILD_INFO_HEADER_WIDTH, > + "-----------------"); > + for (size_t i = 0; i < BUILD_INFO_SIZE ; i++) { > + printf(" %-*s %s\n", > + BUILD_INFO_HEADER_WIDTH, > + BUILD_INFO[i].key, > + BUILD_INFO[i].value); > + } > + } > +} > + > enum { > > #define DEF(option, opt_arg, opt_enum, opt_help, arch_mask) \ > @@ -3019,6 +3054,12 @@ void qemu_init(int argc, char **argv) > version(); > exit(0); > break; > + case QEMU_OPTION_build_info: > + /* fallthrough */ > + case QEMU_OPTION_build_info_json: > + build_info(argv[0], popt->index != QEMU_OPTION_build_info); > + exit(0); > + break; > case QEMU_OPTION_m: > opts = qemu_opts_parse_noisily(qemu_find_opts("memory"), optarg, true); > if (opts == NULL) { > > --- > base-commit: 01dc65a3bc262ab1bec8fe89775e9bbfa627becb > change-id: 20240922-feature-build-info-cli-c9e08e34c34b > > -- > γαῖα πυρί μιχθήτω > With regards, Daniel
On 9/22/24 23:05, Manos Pitsidianakis wrote: > Add -build-info and -build-info-json CLI arguments for human and machine > readable output of build/compile-time configuration data. The source for > this data is the meson generated config-host.h. > > This information is mainly of interest to developers and other folk who > deal with many different builds of QEMU and need a way to properly > differentiate them. > > Because there's always the chance someone will want to consume an > interface programmatically, also add a -json option that does the same > but outputs a machine-readable JSON object. > > Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> > --- > Changes in v2: > - Fixed alignment of command and documentation in -h output. > - Link to v1: https://lore.kernel.org/r/20240923-feature-build-info-cli-v1-1-e8c42d845390@linaro.org > --- > Notes: > Sample output: > > $ ./qemu-system-aarch64 -build-info > ./qemu-system-aarch64 version 9.1.50 (v9.0.0-3444-g8d988656d8) build information > > configuration key key value > ----------------- --------- > accept4 > af_vsock > asan_iface_fiber > atomic64 > attr > audio_alsa > audio_drivers pa,sndio,oss > audio_oss > audio_pa > audio_pipewire > audio_sdl > audio_sndio > avx2_opt > avx512bw_opt > bdrv_ro_whitelist > bdrv_rw_whitelist > bindir /usr/local/bin > blkzoned > brlapi > capstone > clock_adjtime > close_range > coroutine_pool > cpuid_h > curl > curses > dbus_display > debug_graph_lock > debug_mutex > debug_tcg > dup3 > ebpf > epoll > epoll_create1 > eventfd > fallocate > fallocate_punch_hole > fallocate_zero_range > fdatasync > fdt > fiemap > fsfreeze > fstrim > fuse > fuse_lseek > gbm > getauxval > getcpu > getrandom > gettid > gio > gnutls > gnutls_crypto > gtk > hexagon_idef_parser > host_dsosuf .so > iasl /bin/iasl > inotify > inotify1 > int128 > int128_type > iovec > keyutils > kvm_targets i386-softmmu,x86_64-softmmu > l2tpv3 > libdw > libudev > linux > linux_io_uring > linux_magic_h > madvise > malloc_trim > memalign > memfd > opengl > open_by_handle > pixman > plugin > png > posix > posix_fallocate > posix_madvise > posix_memalign > ppoll > prctl_pr_set_timerslack > preadv > prefix /usr/local > pthread_affinity_np > pthread_setname_np_w_tid > qemu_confdir /usr/local/etc/qemu > qemu_datadir /usr/local/share/qemu > qemu_desktopdir /usr/local/share/applications > qemu_firmwarepath /usr/local/share/qemu-firmware > qemu_helperdir /usr/local/libexec > qemu_icondir /usr/local/share/icons > qemu_localedir /usr/local/share/locale > qemu_localstatedir /var/local > qemu_moddir /usr/local/lib/x86_64-linux-gnu/qemu > qom_cast_debug > relocatable > replication > rtnetlink > sdl > seccomp > seccomp_sysrawrc > secret_keyring > selinux > sendfile > setns > signalfd > slirp > smbd_command /usr/sbin/smbd > splice > statx > statx_mnt_id > syncfs > sync_file_range > sysconfdir /usr/local/etc > sysmacros > tasn1 > tcg 1 > timerfd > tls_priority NORMAL > tpm > trace_file trace > trace_log > usbfs > usb_libusb > valgrind_h > valloc > vduse_blk_export > vhost > vhost_crypto > vhost_kernel > vhost_net > vhost_net_user > vhost_net_vdpa > vhost_user > vhost_user_blk_server > vhost_vdpa > virtfs > vnc > vnc_jpeg > vte > x11 > xen_backend > xen_ctrl_interface_version 41700 > xkbcommon > zstd > blk_zone_rep_capacity > btrfs_h > copy_file_range > drm_h > fsxattr > getifaddrs > host_block_device > ipproto_mptcp > mlockall > openpty > pty_h > strchrnul > struct_stat_st_atim > system_function > utmpx > virgl_d3d_info_ext > host_x86_64 1 > qemu_version 9.1.50 > qemu_version_major 9 > qemu_version_micro 50 > qemu_version_minor 1 > This is a nice addition, and an easy way to get access to this information, including for a qemu you compile yourself. If there are some concerns about it becoming a "public API" for consumers, maybe the option could simply be hidden from help, so only qemu devs know it's there. An alternative could be to distribute a "config file" with qemu, like what is available for Linux kernel (cat /boot/config-*). But I really prefer something embedded in binary and accessible via option to be honest. > To: qemu-devel@nongnu.org > Cc: "Cleber Rosa" <crosa@redhat.com> > Cc: "Daniel P. Berrangé" <berrange@redhat.com> > Cc: "John Snow" <jsnow@redhat.com> > Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com> > Cc: "Paolo Bonzini" <pbonzini@redhat.com> > Cc: "Alex Bennée" <alex.bennee@linaro.org> > Cc: "Gustavo Romero" <gustavo.romero@linaro.org> > Cc: "Peter Maydell" <peter.maydell@linaro.org> > Cc: "Philippe Mathieu-Daudé" <philmd@linaro.org> > Cc: "Pierrick Bouvier" <pierrick.bouvier@linaro.org> > Cc: "Richard Henderson" <richard.henderson@linaro.org> > Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> > --- > meson.build | 15 +++++++- > qemu-options.hx | 15 ++++++++ > scripts/build_info_gen.py | 91 +++++++++++++++++++++++++++++++++++++++++++++++ > system/vl.c | 41 +++++++++++++++++++++ > 4 files changed, 161 insertions(+), 1 deletion(-) > > diff --git a/meson.build b/meson.build > index 10464466ff..eff2ee323a 100644 > --- a/meson.build > +++ b/meson.build > @@ -3292,7 +3292,20 @@ endif > # Generated sources # > ##################### > > -genh += configure_file(output: 'config-host.h', configuration: config_host_data) > +config_host_h = configure_file(output: 'config-host.h', configuration: config_host_data) > +genh += config_host_h > + > +build_info_h = custom_target('build-info.h', > + output: 'build-info.h', > + command: [ > + find_program('scripts/build_info_gen.py'), > + '--config-headers', > + config_host_h > + ], > + capture: true, > + build_by_default: true, > + build_always_stale: true) > +genh += build_info_h > > hxtool = find_program('scripts/hxtool') > shaderinclude = find_program('scripts/shaderinclude.py') > diff --git a/qemu-options.hx b/qemu-options.hx > index d94e2cbbae..6a32e0624f 100644 > --- a/qemu-options.hx > +++ b/qemu-options.hx > @@ -24,6 +24,21 @@ SRST > Display version information and exit > ERST > > +DEF("build-info", 0, QEMU_OPTION_build_info, > + "-build-info display build information of executable and exit\n", QEMU_ARCH_ALL) > +SRST > +``-build-info`` > + Display build information of executable and exit > +ERST > + > +DEF("build-info-json", 0, QEMU_OPTION_build_info_json, > + "-build-info-json\n" > + " dump build information of executable in JSON format and exit\n", QEMU_ARCH_ALL) > +SRST > +``-build-info-json`` > + Dump build information of executable in JSON format and exit > +ERST > + > DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ > "-machine [type=]name[,prop[=value][,...]]\n" > " selects emulated machine ('-machine help' for list)\n" > diff --git a/scripts/build_info_gen.py b/scripts/build_info_gen.py > new file mode 100755 > index 0000000000..37a9421651 > --- /dev/null > +++ b/scripts/build_info_gen.py > @@ -0,0 +1,91 @@ > +#!/usr/bin/env python3 > + > +""" > +Generate build information header, build-info.h, > +for output of -build-info* command line arguments. > + > +SPDX-FileContributor: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> > +SPDX-FileCopyrightText: 2024 Linaro Ltd. > +SPDX-License-Identifier: GPL-2.0-or-later > +""" > + > +# Formatted with black --line-length 80 scripts/build-info-gen.py > + > +import argparse > +import logging > + > + > +def generate_key_val(header: str) -> str: > + # pylint: disable=missing-function-docstring > + > + with open(header, encoding="utf-8") as cfg: > + config = [l.split()[1:] for l in cfg if l.startswith("#define")] > + > + for cfg in config: > + if cfg[0].startswith("HAVE_"): > + yield (cfg[0].removeprefix("HAVE_").lower(), None) > + continue > + yield ( > + cfg[0].removeprefix("CONFIG_").lower(), > + ( > + cfg[1] > + if len(cfg) == 2 > + else "".join(cfg[1:]).replace('"', "") if len(cfg) > 2 else None > + ), > + ) > + > + > +def main() -> None: > + # pylint: disable=missing-function-docstring > + parser = argparse.ArgumentParser() > + parser.add_argument("-v", "--verbose", action="store_true") > + parser.add_argument( > + "--config-headers", > + metavar="CONFIG_HEADER", > + action="append", > + dest="config_headers", > + help="paths to configuration host C headers (*.h files)", > + required=False, > + default=[], > + ) > + args = parser.parse_args() > + if args.verbose: > + logging.basicConfig(level=logging.ERROR) > + logging.debug("args: %s", args) > + print( > + """// @generated by scripts/build-info-gen.py > + > +#include <stddef.h>""" > + ) > + print( > + """static struct build_info_t { > + const char *key; > + const char *value; > +} BUILD_INFO[] = {""" > + ) > + total = 0 > + header_width = 0 > + for header in args.config_headers: > + for key, val in generate_key_val(header): > + total += 1 > + header_width = max(header_width, len(key)) > + print( > + '{"', > + key, > + '", "', > + val.strip('"').strip(",").strip('"') if val else "", > + '"},', > + sep="", > + ) > + print("};") > + print("\nstatic size_t BUILD_INFO_SIZE = ", total, ";", sep="") > + print( > + "static unsigned int BUILD_INFO_HEADER_WIDTH = ", > + header_width, > + ";", > + sep="", > + ) > + > + > +if __name__ == "__main__": > + main() > diff --git a/system/vl.c b/system/vl.c > index fe547ca47c..5266b85d22 100644 > --- a/system/vl.c > +++ b/system/vl.c > @@ -908,6 +908,41 @@ static void help(int exitcode) > exit(exitcode); > } > > +static void build_info(const char *execname, bool as_json) > +{ > +#include "build-info.h" > + if (as_json) { > + printf("{\n"); > + for (size_t i = 0; i + 1 < BUILD_INFO_SIZE ; i++) { > + printf("\"%s\":\"%s\",\n", > + BUILD_INFO[i].key, > + BUILD_INFO[i].value); > + } > + if (BUILD_INFO_SIZE > 0) { > + printf("\"%s\":\"%s\"\n", > + BUILD_INFO[BUILD_INFO_SIZE - 1].key, > + BUILD_INFO[BUILD_INFO_SIZE - 1].value); > + } > + printf("}\n"); > + } else { > + printf("%s version " > + QEMU_FULL_VERSION > + " build information\n\n", execname ?:"QEMU"); > + printf(" %-*s key value\n", > + BUILD_INFO_HEADER_WIDTH, > + "configuration key"); > + printf(" %-*s ---------\n", > + BUILD_INFO_HEADER_WIDTH, > + "-----------------"); > + for (size_t i = 0; i < BUILD_INFO_SIZE ; i++) { > + printf(" %-*s %s\n", > + BUILD_INFO_HEADER_WIDTH, > + BUILD_INFO[i].key, > + BUILD_INFO[i].value); > + } > + } > +} > + > enum { > > #define DEF(option, opt_arg, opt_enum, opt_help, arch_mask) \ > @@ -3019,6 +3054,12 @@ void qemu_init(int argc, char **argv) > version(); > exit(0); > break; > + case QEMU_OPTION_build_info: > + /* fallthrough */ > + case QEMU_OPTION_build_info_json: > + build_info(argv[0], popt->index != QEMU_OPTION_build_info); > + exit(0); > + break; > case QEMU_OPTION_m: > opts = qemu_opts_parse_noisily(qemu_find_opts("memory"), optarg, true); > if (opts == NULL) { > > --- > base-commit: 01dc65a3bc262ab1bec8fe89775e9bbfa627becb > change-id: 20240922-feature-build-info-cli-c9e08e34c34b > > -- > γαῖα πυρί μιχθήτω >
Hello Daniel, On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" <berrange@redhat.com> wrote: >On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: >> Add -build-info and -build-info-json CLI arguments for human and machine >> readable output of build/compile-time configuration data. The source for >> this data is the meson generated config-host.h. >> >> This information is mainly of interest to developers and other folk who >> deal with many different builds of QEMU and need a way to properly >> differentiate them. >> >> Because there's always the chance someone will want to consume an >> interface programmatically, also add a -json option that does the same >> but outputs a machine-readable JSON object. > >This turns our build system configuration information into a >defacto public API, and while its using JSON, it isn't yusing >QAPI. > >To some degree we leak our build system config names externally >because the "if" stanzas in the QAPI schema get copied into the >docs. > >Overall though I don't think we should be exposing this build >config infomation externally. We've had many times, particularly >with testing, where people have wanted to access CONFIG_XXX info >about a QEMU binary, but IIRC we've always steered people towards >querying for the actual feature they want, rather than looking >at CONFIG_XXX settings. > >ie, look a query-audiodevs to discover what audio baxckends are >built-in, don't look for CONFIG_XXX settings related to audio. >If there are gaps in information we can query from QMP, we should >aim to close those gaps. > >IOW, I don't think we should expose this build info info in either >human readable or machine readable format. QAPI/QMP is not the perspective of this patch, this is for people who use custom-built (i.e. not from a distro) binaries and want to be able to identify how it was built. Launching a binary to query stuff is unnecessarily complex for this task, and the info is not generally interesting to the API consumers as you said. Manos > >> >> Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> >> --- >> Changes in v2: >> - Fixed alignment of command and documentation in -h output. >> - Link to v1: https://lore.kernel.org/r/20240923-feature-build-info-cli-v1-1-e8c42d845390@linaro.org >> --- >> Notes: >> Sample output: >> >> $ ./qemu-system-aarch64 -build-info >> ./qemu-system-aarch64 version 9.1.50 (v9.0.0-3444-g8d988656d8) build information >> >> configuration key key value >> ----------------- --------- >> accept4 >> af_vsock >> asan_iface_fiber >> atomic64 >> attr >> audio_alsa >> audio_drivers pa,sndio,oss >> audio_oss >> audio_pa >> audio_pipewire >> audio_sdl >> audio_sndio >> avx2_opt >> avx512bw_opt >> bdrv_ro_whitelist >> bdrv_rw_whitelist >> bindir /usr/local/bin >> blkzoned >> brlapi >> capstone >> clock_adjtime >> close_range >> coroutine_pool >> cpuid_h >> curl >> curses >> dbus_display >> debug_graph_lock >> debug_mutex >> debug_tcg >> dup3 >> ebpf >> epoll >> epoll_create1 >> eventfd >> fallocate >> fallocate_punch_hole >> fallocate_zero_range >> fdatasync >> fdt >> fiemap >> fsfreeze >> fstrim >> fuse >> fuse_lseek >> gbm >> getauxval >> getcpu >> getrandom >> gettid >> gio >> gnutls >> gnutls_crypto >> gtk >> hexagon_idef_parser >> host_dsosuf .so >> iasl /bin/iasl >> inotify >> inotify1 >> int128 >> int128_type >> iovec >> keyutils >> kvm_targets i386-softmmu,x86_64-softmmu >> l2tpv3 >> libdw >> libudev >> linux >> linux_io_uring >> linux_magic_h >> madvise >> malloc_trim >> memalign >> memfd >> opengl >> open_by_handle >> pixman >> plugin >> png >> posix >> posix_fallocate >> posix_madvise >> posix_memalign >> ppoll >> prctl_pr_set_timerslack >> preadv >> prefix /usr/local >> pthread_affinity_np >> pthread_setname_np_w_tid >> qemu_confdir /usr/local/etc/qemu >> qemu_datadir /usr/local/share/qemu >> qemu_desktopdir /usr/local/share/applications >> qemu_firmwarepath /usr/local/share/qemu-firmware >> qemu_helperdir /usr/local/libexec >> qemu_icondir /usr/local/share/icons >> qemu_localedir /usr/local/share/locale >> qemu_localstatedir /var/local >> qemu_moddir /usr/local/lib/x86_64-linux-gnu/qemu >> qom_cast_debug >> relocatable >> replication >> rtnetlink >> sdl >> seccomp >> seccomp_sysrawrc >> secret_keyring >> selinux >> sendfile >> setns >> signalfd >> slirp >> smbd_command /usr/sbin/smbd >> splice >> statx >> statx_mnt_id >> syncfs >> sync_file_range >> sysconfdir /usr/local/etc >> sysmacros >> tasn1 >> tcg 1 >> timerfd >> tls_priority NORMAL >> tpm >> trace_file trace >> trace_log >> usbfs >> usb_libusb >> valgrind_h >> valloc >> vduse_blk_export >> vhost >> vhost_crypto >> vhost_kernel >> vhost_net >> vhost_net_user >> vhost_net_vdpa >> vhost_user >> vhost_user_blk_server >> vhost_vdpa >> virtfs >> vnc >> vnc_jpeg >> vte >> x11 >> xen_backend >> xen_ctrl_interface_version 41700 >> xkbcommon >> zstd >> blk_zone_rep_capacity >> btrfs_h >> copy_file_range >> drm_h >> fsxattr >> getifaddrs >> host_block_device >> ipproto_mptcp >> mlockall >> openpty >> pty_h >> strchrnul >> struct_stat_st_atim >> system_function >> utmpx >> virgl_d3d_info_ext >> host_x86_64 1 >> qemu_version 9.1.50 >> qemu_version_major 9 >> qemu_version_micro 50 >> qemu_version_minor 1 >> >> To: qemu-devel@nongnu.org >> Cc: "Cleber Rosa" <crosa@redhat.com> >> Cc: "Daniel P. Berrangé" <berrange@redhat.com> >> Cc: "John Snow" <jsnow@redhat.com> >> Cc: "Marc-André Lureau" <marcandre.lureau@redhat.com> >> Cc: "Paolo Bonzini" <pbonzini@redhat.com> >> Cc: "Alex Bennée" <alex.bennee@linaro.org> >> Cc: "Gustavo Romero" <gustavo.romero@linaro.org> >> Cc: "Peter Maydell" <peter.maydell@linaro.org> >> Cc: "Philippe Mathieu-Daudé" <philmd@linaro.org> >> Cc: "Pierrick Bouvier" <pierrick.bouvier@linaro.org> >> Cc: "Richard Henderson" <richard.henderson@linaro.org> >> Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> >> --- >> meson.build | 15 +++++++- >> qemu-options.hx | 15 ++++++++ >> scripts/build_info_gen.py | 91 +++++++++++++++++++++++++++++++++++++++++++++++ >> system/vl.c | 41 +++++++++++++++++++++ >> 4 files changed, 161 insertions(+), 1 deletion(-) >> >> diff --git a/meson.build b/meson.build >> index 10464466ff..eff2ee323a 100644 >> --- a/meson.build >> +++ b/meson.build >> @@ -3292,7 +3292,20 @@ endif >> # Generated sources # >> ##################### >> >> -genh += configure_file(output: 'config-host.h', configuration: config_host_data) >> +config_host_h = configure_file(output: 'config-host.h', configuration: config_host_data) >> +genh += config_host_h >> + >> +build_info_h = custom_target('build-info.h', >> + output: 'build-info.h', >> + command: [ >> + find_program('scripts/build_info_gen.py'), >> + '--config-headers', >> + config_host_h >> + ], >> + capture: true, >> + build_by_default: true, >> + build_always_stale: true) >> +genh += build_info_h >> >> hxtool = find_program('scripts/hxtool') >> shaderinclude = find_program('scripts/shaderinclude.py') >> diff --git a/qemu-options.hx b/qemu-options.hx >> index d94e2cbbae..6a32e0624f 100644 >> --- a/qemu-options.hx >> +++ b/qemu-options.hx >> @@ -24,6 +24,21 @@ SRST >> Display version information and exit >> ERST >> >> +DEF("build-info", 0, QEMU_OPTION_build_info, >> + "-build-info display build information of executable and exit\n", QEMU_ARCH_ALL) >> +SRST >> +``-build-info`` >> + Display build information of executable and exit >> +ERST >> + >> +DEF("build-info-json", 0, QEMU_OPTION_build_info_json, >> + "-build-info-json\n" >> + " dump build information of executable in JSON format and exit\n", QEMU_ARCH_ALL) >> +SRST >> +``-build-info-json`` >> + Dump build information of executable in JSON format and exit >> +ERST >> + >> DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ >> "-machine [type=]name[,prop[=value][,...]]\n" >> " selects emulated machine ('-machine help' for list)\n" >> diff --git a/scripts/build_info_gen.py b/scripts/build_info_gen.py >> new file mode 100755 >> index 0000000000..37a9421651 >> --- /dev/null >> +++ b/scripts/build_info_gen.py >> @@ -0,0 +1,91 @@ >> +#!/usr/bin/env python3 >> + >> +""" >> +Generate build information header, build-info.h, >> +for output of -build-info* command line arguments. >> + >> +SPDX-FileContributor: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> >> +SPDX-FileCopyrightText: 2024 Linaro Ltd. >> +SPDX-License-Identifier: GPL-2.0-or-later >> +""" >> + >> +# Formatted with black --line-length 80 scripts/build-info-gen.py >> + >> +import argparse >> +import logging >> + >> + >> +def generate_key_val(header: str) -> str: >> + # pylint: disable=missing-function-docstring >> + >> + with open(header, encoding="utf-8") as cfg: >> + config = [l.split()[1:] for l in cfg if l.startswith("#define")] >> + >> + for cfg in config: >> + if cfg[0].startswith("HAVE_"): >> + yield (cfg[0].removeprefix("HAVE_").lower(), None) >> + continue >> + yield ( >> + cfg[0].removeprefix("CONFIG_").lower(), >> + ( >> + cfg[1] >> + if len(cfg) == 2 >> + else "".join(cfg[1:]).replace('"', "") if len(cfg) > 2 else None >> + ), >> + ) >> + >> + >> +def main() -> None: >> + # pylint: disable=missing-function-docstring >> + parser = argparse.ArgumentParser() >> + parser.add_argument("-v", "--verbose", action="store_true") >> + parser.add_argument( >> + "--config-headers", >> + metavar="CONFIG_HEADER", >> + action="append", >> + dest="config_headers", >> + help="paths to configuration host C headers (*.h files)", >> + required=False, >> + default=[], >> + ) >> + args = parser.parse_args() >> + if args.verbose: >> + logging.basicConfig(level=logging.ERROR) >> + logging.debug("args: %s", args) >> + print( >> + """// @generated by scripts/build-info-gen.py >> + >> +#include <stddef.h>""" >> + ) >> + print( >> + """static struct build_info_t { >> + const char *key; >> + const char *value; >> +} BUILD_INFO[] = {""" >> + ) >> + total = 0 >> + header_width = 0 >> + for header in args.config_headers: >> + for key, val in generate_key_val(header): >> + total += 1 >> + header_width = max(header_width, len(key)) >> + print( >> + '{"', >> + key, >> + '", "', >> + val.strip('"').strip(",").strip('"') if val else "", >> + '"},', >> + sep="", >> + ) >> + print("};") >> + print("\nstatic size_t BUILD_INFO_SIZE = ", total, ";", sep="") >> + print( >> + "static unsigned int BUILD_INFO_HEADER_WIDTH = ", >> + header_width, >> + ";", >> + sep="", >> + ) >> + >> + >> +if __name__ == "__main__": >> + main() >> diff --git a/system/vl.c b/system/vl.c >> index fe547ca47c..5266b85d22 100644 >> --- a/system/vl.c >> +++ b/system/vl.c >> @@ -908,6 +908,41 @@ static void help(int exitcode) >> exit(exitcode); >> } >> >> +static void build_info(const char *execname, bool as_json) >> +{ >> +#include "build-info.h" >> + if (as_json) { >> + printf("{\n"); >> + for (size_t i = 0; i + 1 < BUILD_INFO_SIZE ; i++) { >> + printf("\"%s\":\"%s\",\n", >> + BUILD_INFO[i].key, >> + BUILD_INFO[i].value); >> + } >> + if (BUILD_INFO_SIZE > 0) { >> + printf("\"%s\":\"%s\"\n", >> + BUILD_INFO[BUILD_INFO_SIZE - 1].key, >> + BUILD_INFO[BUILD_INFO_SIZE - 1].value); >> + } >> + printf("}\n"); >> + } else { >> + printf("%s version " >> + QEMU_FULL_VERSION >> + " build information\n\n", execname ?:"QEMU"); >> + printf(" %-*s key value\n", >> + BUILD_INFO_HEADER_WIDTH, >> + "configuration key"); >> + printf(" %-*s ---------\n", >> + BUILD_INFO_HEADER_WIDTH, >> + "-----------------"); >> + for (size_t i = 0; i < BUILD_INFO_SIZE ; i++) { >> + printf(" %-*s %s\n", >> + BUILD_INFO_HEADER_WIDTH, >> + BUILD_INFO[i].key, >> + BUILD_INFO[i].value); >> + } >> + } >> +} >> + >> enum { >> >> #define DEF(option, opt_arg, opt_enum, opt_help, arch_mask) \ >> @@ -3019,6 +3054,12 @@ void qemu_init(int argc, char **argv) >> version(); >> exit(0); >> break; >> + case QEMU_OPTION_build_info: >> + /* fallthrough */ >> + case QEMU_OPTION_build_info_json: >> + build_info(argv[0], popt->index != QEMU_OPTION_build_info); >> + exit(0); >> + break; >> case QEMU_OPTION_m: >> opts = qemu_opts_parse_noisily(qemu_find_opts("memory"), optarg, true); >> if (opts == NULL) { >> >> --- >> base-commit: 01dc65a3bc262ab1bec8fe89775e9bbfa627becb >> change-id: 20240922-feature-build-info-cli-c9e08e34c34b >> >> -- >> γαῖα πυρί μιχθήτω >> > >With regards, >Daniel >-- >|: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| >|: https://libvirt.org -o- https://fstop138.berrange.com :| >|: https://entangle-photo.org -o- https://www.instagram.com/dberrange :| >
On Mon, Sep 23, 2024 at 10:09:32PM +0300, Manos Pitsidianakis wrote: > Hello Daniel, > > On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" <berrange@redhat.com> wrote: > > On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: > > > Add -build-info and -build-info-json CLI arguments for human and machine > > > readable output of build/compile-time configuration data. The source for > > > this data is the meson generated config-host.h. > > > > > > This information is mainly of interest to developers and other folk who > > > deal with many different builds of QEMU and need a way to properly > > > differentiate them. > > > > > > Because there's always the chance someone will want to consume an > > > interface programmatically, also add a -json option that does the same > > > but outputs a machine-readable JSON object. > > > > This turns our build system configuration information into a > > defacto public API, and while its using JSON, it isn't yusing > > QAPI. > > > > To some degree we leak our build system config names externally > > because the "if" stanzas in the QAPI schema get copied into the > > docs. > > > > Overall though I don't think we should be exposing this build > > config infomation externally. We've had many times, particularly > > with testing, where people have wanted to access CONFIG_XXX info > > about a QEMU binary, but IIRC we've always steered people towards > > querying for the actual feature they want, rather than looking > > at CONFIG_XXX settings. > > > > ie, look a query-audiodevs to discover what audio baxckends are > > built-in, don't look for CONFIG_XXX settings related to audio. > > If there are gaps in information we can query from QMP, we should > > aim to close those gaps. > > > > IOW, I don't think we should expose this build info info in either > > human readable or machine readable format. > > QAPI/QMP is not the perspective of this patch, this is for people who use > custom-built (i.e. not from a distro) binaries and want to be able to > identify how it was built. Launching a binary to query stuff is > unnecessarily complex for this task, and the info is not generally > interesting to the API consumers as you said. Launching QEMU to talk QMP is our defined public API for querying anything about the capabilities of QEMU. We're worked hard to get away from providing ad-hoc ways to query QEMU from the command line and going back to that is not desirable. It may be slightly more complicated, but not by very much. With regards, Daniel
Hello Daniel, On Tue, 24 Sept 2024 at 11:45, Daniel P. Berrangé <berrange@redhat.com> wrote: > > On Mon, Sep 23, 2024 at 10:09:32PM +0300, Manos Pitsidianakis wrote: > > Hello Daniel, > > > > On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" <berrange@redhat.com> wrote: > > > On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: > > > > Add -build-info and -build-info-json CLI arguments for human and machine > > > > readable output of build/compile-time configuration data. The source for > > > > this data is the meson generated config-host.h. > > > > > > > > This information is mainly of interest to developers and other folk who > > > > deal with many different builds of QEMU and need a way to properly > > > > differentiate them. > > > > > > > > Because there's always the chance someone will want to consume an > > > > interface programmatically, also add a -json option that does the same > > > > but outputs a machine-readable JSON object. > > > > > > This turns our build system configuration information into a > > > defacto public API, and while its using JSON, it isn't yusing > > > QAPI. > > > > > > To some degree we leak our build system config names externally > > > because the "if" stanzas in the QAPI schema get copied into the > > > docs. > > > > > > Overall though I don't think we should be exposing this build > > > config infomation externally. We've had many times, particularly > > > with testing, where people have wanted to access CONFIG_XXX info > > > about a QEMU binary, but IIRC we've always steered people towards > > > querying for the actual feature they want, rather than looking > > > at CONFIG_XXX settings. > > > > > > ie, look a query-audiodevs to discover what audio baxckends are > > > built-in, don't look for CONFIG_XXX settings related to audio. > > > If there are gaps in information we can query from QMP, we should > > > aim to close those gaps. > > > > > > IOW, I don't think we should expose this build info info in either > > > human readable or machine readable format. > > > > QAPI/QMP is not the perspective of this patch, this is for people who use > > custom-built (i.e. not from a distro) binaries and want to be able to > > identify how it was built. Launching a binary to query stuff is > > unnecessarily complex for this task, and the info is not generally > > interesting to the API consumers as you said. > > Launching QEMU to talk QMP is our defined public API for querying > anything about the capabilities of QEMU. We're worked hard to get > away from providing ad-hoc ways to query QEMU from the command > line and going back to that is not desirable. It may be slightly > more complicated, but not by very much. Again, this is not a "capabilities discovery" API. It lists the build-time configuration of the binary. Perhaps we can expose it in a different way so that people don't end up confused? Manos
Manos Pitsidianakis <manos.pitsidianakis@linaro.org> writes: > Hello Daniel, > > On Tue, 24 Sept 2024 at 11:45, Daniel P. Berrangé <berrange@redhat.com> wrote: >> >> On Mon, Sep 23, 2024 at 10:09:32PM +0300, Manos Pitsidianakis wrote: >> > Hello Daniel, >> > >> > On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" <berrange@redhat.com> wrote: >> > > On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: <snip> >> > > ie, look a query-audiodevs to discover what audio baxckends are >> > > built-in, don't look for CONFIG_XXX settings related to audio. >> > > If there are gaps in information we can query from QMP, we should >> > > aim to close those gaps. >> > > >> > > IOW, I don't think we should expose this build info info in either >> > > human readable or machine readable format. >> > >> > QAPI/QMP is not the perspective of this patch, this is for people who use >> > custom-built (i.e. not from a distro) binaries and want to be able to >> > identify how it was built. Launching a binary to query stuff is >> > unnecessarily complex for this task, and the info is not generally >> > interesting to the API consumers as you said. >> >> Launching QEMU to talk QMP is our defined public API for querying >> anything about the capabilities of QEMU. We're worked hard to get >> away from providing ad-hoc ways to query QEMU from the command >> line and going back to that is not desirable. It may be slightly >> more complicated, but not by very much. > > Again, this is not a "capabilities discovery" API. It lists the > build-time configuration of the binary. Perhaps we can expose it in a > different way so that people don't end up confused? I think the problem is however much we might say it's not a capabilities discovery API it's very existence encourages users to use it as one. What about a script: qemu-get-build-info </path/to/qemu> which would launch the binary and query it over QMP? Would that work?
On Tue, Sep 24, 2024 at 01:02:26PM +0100, Alex Bennée wrote: > Manos Pitsidianakis <manos.pitsidianakis@linaro.org> writes: > > > Hello Daniel, > > > > On Tue, 24 Sept 2024 at 11:45, Daniel P. Berrangé <berrange@redhat.com> wrote: > >> > >> On Mon, Sep 23, 2024 at 10:09:32PM +0300, Manos Pitsidianakis wrote: > >> > Hello Daniel, > >> > > >> > On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" <berrange@redhat.com> wrote: > >> > > On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: > <snip> > >> > > ie, look a query-audiodevs to discover what audio baxckends are > >> > > built-in, don't look for CONFIG_XXX settings related to audio. > >> > > If there are gaps in information we can query from QMP, we should > >> > > aim to close those gaps. > >> > > > >> > > IOW, I don't think we should expose this build info info in either > >> > > human readable or machine readable format. > >> > > >> > QAPI/QMP is not the perspective of this patch, this is for people who use > >> > custom-built (i.e. not from a distro) binaries and want to be able to > >> > identify how it was built. Launching a binary to query stuff is > >> > unnecessarily complex for this task, and the info is not generally > >> > interesting to the API consumers as you said. > >> > >> Launching QEMU to talk QMP is our defined public API for querying > >> anything about the capabilities of QEMU. We're worked hard to get > >> away from providing ad-hoc ways to query QEMU from the command > >> line and going back to that is not desirable. It may be slightly > >> more complicated, but not by very much. > > > > Again, this is not a "capabilities discovery" API. It lists the > > build-time configuration of the binary. Perhaps we can expose it in a > > different way so that people don't end up confused? > > I think the problem is however much we might say it's not a capabilities > discovery API it's very existence encourages users to use it as one. > > What about a script: > > qemu-get-build-info </path/to/qemu> > > which would launch the binary and query it over QMP? Would that work? If this is purely a debugging aid, we could make use of ELF notes to just stick the config-host.h content into the binary. This has precedent in systemd package notes (https://github.com/systemd/package-notes) and is more clearly *NOT* an end user CLI option, nor a public API in QMP. Querying is then objdump -j .note.qemu-config-h -s /usrbin/qemu-system-x86_64 With regards, Daniel
Hello Daniel, On Tue, Sep 24, 2024, 3:08 PM Daniel P. Berrangé <berrange@redhat.com> wrote: > On Tue, Sep 24, 2024 at 01:02:26PM +0100, Alex Bennée wrote: > > Manos Pitsidianakis <manos.pitsidianakis@linaro.org> writes: > > > > > Hello Daniel, > > > > > > On Tue, 24 Sept 2024 at 11:45, Daniel P. Berrangé <berrange@redhat.com> > wrote: > > >> > > >> On Mon, Sep 23, 2024 at 10:09:32PM +0300, Manos Pitsidianakis wrote: > > >> > Hello Daniel, > > >> > > > >> > On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" < > berrange@redhat.com> wrote: > > >> > > On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis > wrote: > > <snip> > > >> > > ie, look a query-audiodevs to discover what audio baxckends are > > >> > > built-in, don't look for CONFIG_XXX settings related to audio. > > >> > > If there are gaps in information we can query from QMP, we should > > >> > > aim to close those gaps. > > >> > > > > >> > > IOW, I don't think we should expose this build info info in either > > >> > > human readable or machine readable format. > > >> > > > >> > QAPI/QMP is not the perspective of this patch, this is for people > who use > > >> > custom-built (i.e. not from a distro) binaries and want to be able > to > > >> > identify how it was built. Launching a binary to query stuff is > > >> > unnecessarily complex for this task, and the info is not generally > > >> > interesting to the API consumers as you said. > > >> > > >> Launching QEMU to talk QMP is our defined public API for querying > > >> anything about the capabilities of QEMU. We're worked hard to get > > >> away from providing ad-hoc ways to query QEMU from the command > > >> line and going back to that is not desirable. It may be slightly > > >> more complicated, but not by very much. > > > > > > Again, this is not a "capabilities discovery" API. It lists the > > > build-time configuration of the binary. Perhaps we can expose it in a > > > different way so that people don't end up confused? > > > > I think the problem is however much we might say it's not a capabilities > > discovery API it's very existence encourages users to use it as one. > > > > What about a script: > > > > qemu-get-build-info </path/to/qemu> > > > > which would launch the binary and query it over QMP? Would that work? > > If this is purely a debugging aid, we could make use of ELF notes to > just stick the config-host.h content into the binary. This has precedent > in systemd package notes (https://github.com/systemd/package-notes) and > is more clearly *NOT* an end user CLI option, nor a public API in QMP. > > Querying is then > > objdump -j .note.qemu-config-h -s /usrbin/qemu-system-x86_64 > That's actually a way better solution! I will attempt it for the next revision. Manos >
On 9/24/24 05:08, Daniel P. Berrangé wrote: > On Tue, Sep 24, 2024 at 01:02:26PM +0100, Alex Bennée wrote: >> Manos Pitsidianakis <manos.pitsidianakis@linaro.org> writes: >> >>> Hello Daniel, >>> >>> On Tue, 24 Sept 2024 at 11:45, Daniel P. Berrangé <berrange@redhat.com> wrote: >>>> >>>> On Mon, Sep 23, 2024 at 10:09:32PM +0300, Manos Pitsidianakis wrote: >>>>> Hello Daniel, >>>>> >>>>> On Mon, 23 Sep 2024 19:45, "Daniel P. Berrangé" <berrange@redhat.com> wrote: >>>>>> On Mon, Sep 23, 2024 at 09:05:24AM +0300, Manos Pitsidianakis wrote: >> <snip> >>>>>> ie, look a query-audiodevs to discover what audio baxckends are >>>>>> built-in, don't look for CONFIG_XXX settings related to audio. >>>>>> If there are gaps in information we can query from QMP, we should >>>>>> aim to close those gaps. >>>>>> >>>>>> IOW, I don't think we should expose this build info info in either >>>>>> human readable or machine readable format. >>>>> >>>>> QAPI/QMP is not the perspective of this patch, this is for people who use >>>>> custom-built (i.e. not from a distro) binaries and want to be able to >>>>> identify how it was built. Launching a binary to query stuff is >>>>> unnecessarily complex for this task, and the info is not generally >>>>> interesting to the API consumers as you said. >>>> >>>> Launching QEMU to talk QMP is our defined public API for querying >>>> anything about the capabilities of QEMU. We're worked hard to get >>>> away from providing ad-hoc ways to query QEMU from the command >>>> line and going back to that is not desirable. It may be slightly >>>> more complicated, but not by very much. >>> >>> Again, this is not a "capabilities discovery" API. It lists the >>> build-time configuration of the binary. Perhaps we can expose it in a >>> different way so that people don't end up confused? >> >> I think the problem is however much we might say it's not a capabilities >> discovery API it's very existence encourages users to use it as one. >> >> What about a script: >> >> qemu-get-build-info </path/to/qemu> >> >> which would launch the binary and query it over QMP? Would that work? > > If this is purely a debugging aid, we could make use of ELF notes to > just stick the config-host.h content into the binary. This has precedent > in systemd package notes (https://github.com/systemd/package-notes) and > is more clearly *NOT* an end user CLI option, nor a public API in QMP. > > Querying is then > > objdump -j .note.qemu-config-h -s /usrbin/qemu-system-x86_64 > > > With regards, > Daniel This is neat! @Manos: it would be convenient to still have a script as Alex mentioned, as remembering in which notes the information is hidden might be annoying.
diff --git a/meson.build b/meson.build index 10464466ff..eff2ee323a 100644 --- a/meson.build +++ b/meson.build @@ -3292,7 +3292,20 @@ endif # Generated sources # ##################### -genh += configure_file(output: 'config-host.h', configuration: config_host_data) +config_host_h = configure_file(output: 'config-host.h', configuration: config_host_data) +genh += config_host_h + +build_info_h = custom_target('build-info.h', + output: 'build-info.h', + command: [ + find_program('scripts/build_info_gen.py'), + '--config-headers', + config_host_h + ], + capture: true, + build_by_default: true, + build_always_stale: true) +genh += build_info_h hxtool = find_program('scripts/hxtool') shaderinclude = find_program('scripts/shaderinclude.py') diff --git a/qemu-options.hx b/qemu-options.hx index d94e2cbbae..6a32e0624f 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -24,6 +24,21 @@ SRST Display version information and exit ERST +DEF("build-info", 0, QEMU_OPTION_build_info, + "-build-info display build information of executable and exit\n", QEMU_ARCH_ALL) +SRST +``-build-info`` + Display build information of executable and exit +ERST + +DEF("build-info-json", 0, QEMU_OPTION_build_info_json, + "-build-info-json\n" + " dump build information of executable in JSON format and exit\n", QEMU_ARCH_ALL) +SRST +``-build-info-json`` + Dump build information of executable in JSON format and exit +ERST + DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ "-machine [type=]name[,prop[=value][,...]]\n" " selects emulated machine ('-machine help' for list)\n" diff --git a/scripts/build_info_gen.py b/scripts/build_info_gen.py new file mode 100755 index 0000000000..37a9421651 --- /dev/null +++ b/scripts/build_info_gen.py @@ -0,0 +1,91 @@ +#!/usr/bin/env python3 + +""" +Generate build information header, build-info.h, +for output of -build-info* command line arguments. + +SPDX-FileContributor: Manos Pitsidianakis <manos.pitsidianakis@linaro.org> +SPDX-FileCopyrightText: 2024 Linaro Ltd. +SPDX-License-Identifier: GPL-2.0-or-later +""" + +# Formatted with black --line-length 80 scripts/build-info-gen.py + +import argparse +import logging + + +def generate_key_val(header: str) -> str: + # pylint: disable=missing-function-docstring + + with open(header, encoding="utf-8") as cfg: + config = [l.split()[1:] for l in cfg if l.startswith("#define")] + + for cfg in config: + if cfg[0].startswith("HAVE_"): + yield (cfg[0].removeprefix("HAVE_").lower(), None) + continue + yield ( + cfg[0].removeprefix("CONFIG_").lower(), + ( + cfg[1] + if len(cfg) == 2 + else "".join(cfg[1:]).replace('"', "") if len(cfg) > 2 else None + ), + ) + + +def main() -> None: + # pylint: disable=missing-function-docstring + parser = argparse.ArgumentParser() + parser.add_argument("-v", "--verbose", action="store_true") + parser.add_argument( + "--config-headers", + metavar="CONFIG_HEADER", + action="append", + dest="config_headers", + help="paths to configuration host C headers (*.h files)", + required=False, + default=[], + ) + args = parser.parse_args() + if args.verbose: + logging.basicConfig(level=logging.ERROR) + logging.debug("args: %s", args) + print( + """// @generated by scripts/build-info-gen.py + +#include <stddef.h>""" + ) + print( + """static struct build_info_t { + const char *key; + const char *value; +} BUILD_INFO[] = {""" + ) + total = 0 + header_width = 0 + for header in args.config_headers: + for key, val in generate_key_val(header): + total += 1 + header_width = max(header_width, len(key)) + print( + '{"', + key, + '", "', + val.strip('"').strip(",").strip('"') if val else "", + '"},', + sep="", + ) + print("};") + print("\nstatic size_t BUILD_INFO_SIZE = ", total, ";", sep="") + print( + "static unsigned int BUILD_INFO_HEADER_WIDTH = ", + header_width, + ";", + sep="", + ) + + +if __name__ == "__main__": + main() diff --git a/system/vl.c b/system/vl.c index fe547ca47c..5266b85d22 100644 --- a/system/vl.c +++ b/system/vl.c @@ -908,6 +908,41 @@ static void help(int exitcode) exit(exitcode); } +static void build_info(const char *execname, bool as_json) +{ +#include "build-info.h" + if (as_json) { + printf("{\n"); + for (size_t i = 0; i + 1 < BUILD_INFO_SIZE ; i++) { + printf("\"%s\":\"%s\",\n", + BUILD_INFO[i].key, + BUILD_INFO[i].value); + } + if (BUILD_INFO_SIZE > 0) { + printf("\"%s\":\"%s\"\n", + BUILD_INFO[BUILD_INFO_SIZE - 1].key, + BUILD_INFO[BUILD_INFO_SIZE - 1].value); + } + printf("}\n"); + } else { + printf("%s version " + QEMU_FULL_VERSION + " build information\n\n", execname ?:"QEMU"); + printf(" %-*s key value\n", + BUILD_INFO_HEADER_WIDTH, + "configuration key"); + printf(" %-*s ---------\n", + BUILD_INFO_HEADER_WIDTH, + "-----------------"); + for (size_t i = 0; i < BUILD_INFO_SIZE ; i++) { + printf(" %-*s %s\n", + BUILD_INFO_HEADER_WIDTH, + BUILD_INFO[i].key, + BUILD_INFO[i].value); + } + } +} + enum { #define DEF(option, opt_arg, opt_enum, opt_help, arch_mask) \ @@ -3019,6 +3054,12 @@ void qemu_init(int argc, char **argv) version(); exit(0); break; + case QEMU_OPTION_build_info: + /* fallthrough */ + case QEMU_OPTION_build_info_json: + build_info(argv[0], popt->index != QEMU_OPTION_build_info); + exit(0); + break; case QEMU_OPTION_m: opts = qemu_opts_parse_noisily(qemu_find_opts("memory"), optarg, true); if (opts == NULL) {