aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLuc Michel <luc.michel@greensocs.com>2019-01-07 15:23:45 +0000
committerPeter Maydell <peter.maydell@linaro.org>2019-01-07 15:23:45 +0000
commit1a2273369725111a2bbdb602ca7c679d466618b0 (patch)
tree333f59d8f614d91168902f369f5f76a395cd9ec0
parent8f468636189303358da3b365c53cb03ae5497eca (diff)
downloadqemu-arm-1a2273369725111a2bbdb602ca7c679d466618b0.tar.gz
gdbstub: add multiprocess support to '?' packets
The gdb_get_cpu_pid() function does the PID lookup for the given CPU. It checks if the CPU is a direct child of a CPU cluster. If it is, the returned PID is the cluster ID plus one (cluster IDs start at 0, GDB PIDs at 1). When the CPU is not a child of such a container, the PID of the default process is returned. The gdb_fmt_thread_id() function generates the string to be used to identify a given thread, in a response packet for the peer. This function supports generating thread IDs when multiprocess mode is enabled (in the form `p<pid>.<tid>'). Use them in the reply to a '?' request. Signed-off-by: Luc Michel <luc.michel@greensocs.com> Acked-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> Message-id: 20181207090135.7651-4-luc.michel@greensocs.com [PMM: fixed checkpatch blockquote style nit] Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
-rw-r--r--gdbstub.c66
1 files changed, 64 insertions, 2 deletions
diff --git a/gdbstub.c b/gdbstub.c
index 9ac6f19a18..02beb44d97 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -640,6 +640,54 @@ static int memtox(char *buf, const char *mem, int len)
return p - buf;
}
+static uint32_t gdb_get_cpu_pid(const GDBState *s, CPUState *cpu)
+{
+#ifndef CONFIG_USER_ONLY
+ gchar *path, *name = NULL;
+ Object *obj;
+ CPUClusterState *cluster;
+ uint32_t ret;
+
+ path = object_get_canonical_path(OBJECT(cpu));
+
+ if (path == NULL) {
+ /* Return the default process' PID */
+ ret = s->processes[s->process_num - 1].pid;
+ goto out;
+ }
+
+ name = object_get_canonical_path_component(OBJECT(cpu));
+ assert(name != NULL);
+
+ /*
+ * Retrieve the CPU parent path by removing the last '/' and the CPU name
+ * from the CPU canonical path.
+ */
+ path[strlen(path) - strlen(name) - 1] = '\0';
+
+ obj = object_resolve_path_type(path, TYPE_CPU_CLUSTER, NULL);
+
+ if (obj == NULL) {
+ /* Return the default process' PID */
+ ret = s->processes[s->process_num - 1].pid;
+ goto out;
+ }
+
+ cluster = CPU_CLUSTER(obj);
+ ret = cluster->cluster_id + 1;
+
+out:
+ g_free(name);
+ g_free(path);
+
+ return ret;
+
+#else
+ /* TODO: In user mode, we should use the task state PID */
+ return s->processes[s->process_num - 1].pid;
+#endif
+}
+
static const char *get_feature_xml(const char *p, const char **newp,
CPUClass *cc)
{
@@ -909,6 +957,19 @@ static CPUState *find_cpu(uint32_t thread_id)
return NULL;
}
+static char *gdb_fmt_thread_id(const GDBState *s, CPUState *cpu,
+ char *buf, size_t buf_size)
+{
+ if (s->multiprocess) {
+ snprintf(buf, buf_size, "p%02x.%02x",
+ gdb_get_cpu_pid(s, cpu), cpu_gdb_index(cpu));
+ } else {
+ snprintf(buf, buf_size, "%02x", cpu_gdb_index(cpu));
+ }
+
+ return buf;
+}
+
static int is_query_packet(const char *p, const char *query, char separator)
{
unsigned int query_len = strlen(query);
@@ -1020,6 +1081,7 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf)
int ch, reg_size, type, res;
uint8_t mem_buf[MAX_PACKET_LENGTH];
char buf[sizeof(mem_buf) + 1 /* trailing NUL */];
+ char thread_id[16];
uint8_t *registers;
target_ulong addr, len;
@@ -1030,8 +1092,8 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf)
switch(ch) {
case '?':
/* TODO: Make this return the correct value for user-mode. */
- snprintf(buf, sizeof(buf), "T%02xthread:%02x;", GDB_SIGNAL_TRAP,
- cpu_gdb_index(s->c_cpu));
+ snprintf(buf, sizeof(buf), "T%02xthread:%s;", GDB_SIGNAL_TRAP,
+ gdb_fmt_thread_id(s, s->c_cpu, thread_id, sizeof(thread_id)));
put_packet(s, buf);
/* Remove all the breakpoints when this query is issued,
* because gdb is doing and initial connect and the state