Message ID | 20200812115816.4454-1-matthias@weckbecker.name (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | plugins: new syscalls plugin | expand |
Matthias Weckbecker <matthias@weckbecker.name> writes: > This commit adds a new syscalls plugin that displays the syscalls > as they are executed and returned. This plugin outputs the number > of the syscall as well as the syscall return value. > > Works in *-user only. > > Essentially, this commit restores: > > https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg00846.html > > by using the new QEMU plugin API. Sorry I missed this last year, I've queued to plugins/next. That said in it's current form you basically replicate what you already have with -strace: ./qemu-aarch64 -strace -d plugin -plugin ./tests/plugin/libsyscall.so ./tests/tcg/aarch64-linux-user/testthread syscall #214 13165 brk(NULL) = 0x000000000049a000 syscall #214 returned -> 4825088 syscall #214 13165 brk(0x000000000049af90) = 0x000000000049af90 syscall #214 returned -> 4829072 syscall #160 13165 uname(0x5500800498) = 0 syscall #160 returned -> 0 syscall #96 13165 set_tid_address(4825296,0,4294967293,4826880,4825088,253) = 13165 syscall #96 returned -> 13165 So it would be nice to make the default maybe do something more useful (like emulate strace -C output). You could certainly keep the verbose output controlled by a flag. Still as it is it at least ensures we exercise the code ;-)
diff --git a/tests/plugin/Makefile b/tests/plugin/Makefile index e9348fde4a..fc176909e9 100644 --- a/tests/plugin/Makefile +++ b/tests/plugin/Makefile @@ -21,6 +21,7 @@ NAMES += hotblocks NAMES += howvec NAMES += hotpages NAMES += lockstep +NAMES += syscall SONAMES := $(addsuffix .so,$(addprefix lib,$(NAMES))) diff --git a/tests/plugin/syscall.c b/tests/plugin/syscall.c new file mode 100644 index 0000000000..53ee2ab6c4 --- /dev/null +++ b/tests/plugin/syscall.c @@ -0,0 +1,49 @@ +/* + * Copyright (C) 2020, Matthias Weckbecker <matthias@weckbecker.name> + * + * License: GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ +#include <inttypes.h> +#include <assert.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <stdio.h> +#include <glib.h> + +#include <qemu-plugin.h> + +QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION; + +static void vcpu_syscall(qemu_plugin_id_t id, unsigned int vcpu_index, + int64_t num, uint64_t a1, uint64_t a2, + uint64_t a3, uint64_t a4, uint64_t a5, + uint64_t a6, uint64_t a7, uint64_t a8) +{ + g_autofree gchar *out = g_strdup_printf("syscall #%" PRIi64 "\n", num); + qemu_plugin_outs(out); +} + +static void vcpu_syscall_ret(qemu_plugin_id_t id, unsigned int vcpu_idx, + int64_t num, int64_t ret) +{ + g_autofree gchar *out; + out = g_strdup_printf("syscall #%" PRIi64 " returned -> %" PRIi64 "\n", + num, ret); + qemu_plugin_outs(out); +} + +/* ************************************************************************* */ + +static void plugin_exit(qemu_plugin_id_t id, void *p) {} + +QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, + const qemu_info_t *info, + int argc, char **argv) +{ + qemu_plugin_register_vcpu_syscall_cb(id, vcpu_syscall); + qemu_plugin_register_vcpu_syscall_ret_cb(id, vcpu_syscall_ret); + qemu_plugin_register_atexit_cb(id, plugin_exit, NULL); + return 0; +}
This commit adds a new syscalls plugin that displays the syscalls as they are executed and returned. This plugin outputs the number of the syscall as well as the syscall return value. Works in *-user only. Essentially, this commit restores: https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg00846.html by using the new QEMU plugin API. Signed-off-by: Matthias Weckbecker <matthias@weckbecker.name> --- tests/plugin/Makefile | 1 + tests/plugin/syscall.c | 49 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+) create mode 100644 tests/plugin/syscall.c