From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40114) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gNEAi-0007Ic-5T for qemu-devel@nongnu.org; Thu, 15 Nov 2018 04:42:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gNEAb-0004cQ-Qc for qemu-devel@nongnu.org; Thu, 15 Nov 2018 04:42:44 -0500 From: Luc Michel Date: Thu, 15 Nov 2018 10:41:53 +0100 Message-Id: <20181115094207.22846-3-luc.michel@greensocs.com> In-Reply-To: <20181115094207.22846-1-luc.michel@greensocs.com> References: <20181115094207.22846-1-luc.michel@greensocs.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PATCH v6 02/16] gdbstub: introduce GDB processes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Luc Michel , qemu-arm@nongnu.org, Peter Maydell , saipava@xilinx.com, edgari@xilinx.com, alistair@alistair23.me, =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , mark.burton@greensocs.com, Eduardo Habkost Add a structure GDBProcess that represent processes from the GDB semantic point of view. CPUs can be split into different processes, by grouping them under different cpu-cluster objects. Each occurrence of a cpu-cluster object implies the existence of the corresponding process in the GDB stub. The GDB process ID is derived from the corresponding cluster ID as follows: GDB PID =3D cluster ID + 1 This is because PIDs -1 and 0 are reserved in GDB and cannot be used by processes. When no such container are found, all the CPUs are put in a unique GDB process (create_unique_process()). This is also the case when compiled in user mode, where multi-processes do not make much sense for now. Signed-off-by: Luc Michel Acked-by: Alistair Francis Reviewed-by: Edgar E. Iglesias --- gdbstub.c | 87 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) diff --git a/gdbstub.c b/gdbstub.c index c4e4f9f082..26f5a7449a 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -27,10 +27,11 @@ #include "monitor/monitor.h" #include "chardev/char.h" #include "chardev/char-fe.h" #include "sysemu/sysemu.h" #include "exec/gdbstub.h" +#include "hw/cpu/cluster.h" #endif =20 #define MAX_PACKET_LENGTH 4096 =20 #include "qemu/sockets.h" @@ -294,10 +295,15 @@ typedef struct GDBRegisterState { gdb_reg_cb set_reg; const char *xml; struct GDBRegisterState *next; } GDBRegisterState; =20 +typedef struct GDBProcess { + uint32_t pid; + bool attached; +} GDBProcess; + enum RSState { RS_INACTIVE, RS_IDLE, RS_GETLINE, RS_GETLINE_ESC, @@ -322,10 +328,13 @@ typedef struct GDBState { int running_state; #else CharBackend chr; Chardev *mon_chr; #endif + bool multiprocess; + GDBProcess *processes; + int process_num; char syscall_buf[256]; gdb_syscall_complete_cb current_syscall_cb; } GDBState; =20 /* By default use no IRQs and no timers while single stepping so as to @@ -1749,10 +1758,24 @@ void gdb_exit(CPUArchState *env, int code) #ifndef CONFIG_USER_ONLY qemu_chr_fe_deinit(&s->chr, true); #endif } =20 +/* + * Create a unique process containing all the CPUs. + */ +static void create_unique_process(GDBState *s) +{ + GDBProcess *process; + + s->processes =3D g_malloc0(sizeof(GDBProcess)); + s->process_num =3D 1; + process =3D &s->processes[0]; + + process->pid =3D 1; +} + #ifdef CONFIG_USER_ONLY int gdb_handlesig(CPUState *cpu, int sig) { GDBState *s; @@ -1846,10 +1869,11 @@ static bool gdb_accept(void) } =20 s =3D g_malloc0(sizeof(GDBState)); s->c_cpu =3D first_cpu; s->g_cpu =3D first_cpu; + create_unique_process(s); s->fd =3D fd; gdb_has_xml =3D false; =20 gdbserver_state =3D s; return true; @@ -2002,10 +2026,69 @@ static const TypeInfo char_gdb_type_info =3D { .name =3D TYPE_CHARDEV_GDB, .parent =3D TYPE_CHARDEV, .class_init =3D char_gdb_class_init, }; =20 +static int find_cpu_clusters(Object *child, void *opaque) +{ + if (object_dynamic_cast(child, TYPE_CPU_CLUSTER)) { + GDBState *s =3D (GDBState *) opaque; + CPUClusterState *cluster =3D CPU_CLUSTER(child); + GDBProcess *process; + + s->processes =3D g_renew(GDBProcess, s->processes, ++s->process_= num); + + process =3D &s->processes[s->process_num - 1]; + + /* + * GDB process IDs -1 and 0 are reserved. To avoid subtle errors= at + * runtime, we enforce here that the machine does not use a clus= ter ID + * that would lead to PID 0. */ + assert(process->pid !=3D UINT32_MAX); + process->pid =3D cluster->cluster_id + 1; + process->attached =3D false; + + return 0; + } + + return object_child_foreach(child, find_cpu_clusters, opaque); +} + +static int pid_order(const void *a, const void *b) +{ + GDBProcess *pa =3D (GDBProcess *) a; + GDBProcess *pb =3D (GDBProcess *) b; + + if (pa->pid < pb->pid) { + return -1; + } else if (pa->pid > pb->pid) { + return 1; + } else { + return 0; + } +} + +static void create_processes(GDBState *s) +{ + object_child_foreach(object_get_root(), find_cpu_clusters, s); + + if (!s->processes) { + /* No CPU cluster specified by the machine */ + create_unique_process(s); + } else { + /* Sort by PID */ + qsort(s->processes, s->process_num, sizeof(s->processes[0]), pid= _order); + } +} + +static void cleanup_processes(GDBState *s) +{ + g_free(s->processes); + s->process_num =3D 0; + s->processes =3D NULL; +} + int gdbserver_start(const char *device) { trace_gdbstub_op_start(device); =20 GDBState *s; @@ -2058,15 +2141,19 @@ int gdbserver_start(const char *device) NULL, &error_abort); monitor_init(mon_chr, 0); } else { qemu_chr_fe_deinit(&s->chr, true); mon_chr =3D s->mon_chr; + cleanup_processes(s); memset(s, 0, sizeof(GDBState)); s->mon_chr =3D mon_chr; } s->c_cpu =3D first_cpu; s->g_cpu =3D first_cpu; + + create_processes(s); + if (chr) { qemu_chr_fe_init(&s->chr, chr, &error_abort); qemu_chr_fe_set_handlers(&s->chr, gdb_chr_can_receive, gdb_chr_r= eceive, gdb_chr_event, NULL, NULL, NULL, true); } --=20 2.19.1