osdep: Introduce qemu_kill_thread()

Add a function for sending signals to individual threads. It does not make
sense on Windows, so do not provide an implementation, so that if someone
uses it by accident, they will get a linker error.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20250117001542.8290-6-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250207153112.3939799-15-alex.bennee@linaro.org>

diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h
index 112ebdff21d535693342198c4aa43f01025c8459..4397a9068078fba1db1f22501f62177fb0ec21c0 100644 (file)
--- a/include/qemu/osdep.h
+++ b/include/qemu/osdep.h
@@ -631,6 +631,15 @@ bool qemu_write_pidfile(const char *pidfile, Error **errp);
 
 int qemu_get_thread_id(void);
 
+/**
+ * qemu_kill_thread:
+ * @tid: thread id.
+ * @sig: host signal.
+ *
+ * Send @sig to one of QEMU's own threads with identifier @tid.
+ */
+int qemu_kill_thread(int tid, int sig);
+
 #ifndef CONFIG_IOVEC
 struct iovec {
     void *iov_base;

diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index 2bb34dade3b7eea5f6fb9b1da135cb1268ead3fc..a697c602c6028a6ae5704d024fc1a6cfc4b1ae81 100644 (file)
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -111,6 +111,21 @@ int qemu_get_thread_id(void)
 #endif
 }
 
+int qemu_kill_thread(int tid, int sig)
+{
+#if defined(__linux__)
+    return syscall(__NR_tgkill, getpid(), tid, sig);
+#elif defined(__FreeBSD__)
+    return thr_kill2(getpid(), tid, sig);
+#elif defined(__NetBSD__)
+    return _lwp_kill(tid, sig);
+#elif defined(__OpenBSD__)
+    return thrkill(tid, sig, NULL);
+#else
+    return kill(tid, sig);
+#endif
+}
+
 int qemu_daemon(int nochdir, int noclose)
 {
     return daemon(nochdir, noclose);