From f6327dcbf0bc91bb9d99e12232d2b1a2f959fce6 Mon Sep 17 00:00:00 2001 From: Kevin Buettner Date: Tue, 4 Apr 2017 16:17:05 -0700 Subject: [PATCH] Add thread_handle_to_thread_info support for remote targets This patch adds support to remote targets for converting a thread handle to a thread_info struct pointer. A thread handle is fetched via a "handle" attribute which has been added to the qXfer:threads:read query packet. An implementation is provided in gdbserver for targets using the Linux kernel. gdb/gdbserver/ChangeLog: * linux-low.h (struct lwp_info): Add new field, thread_handle. (thread_db_thread_handle): Declare. * linux-low.c (linux_target_ops): Initialize thread_handle. * server.c (handle_qxfer_threads_worker): Add support for "handle" attribute. * target.h (struct target_ops): Add new function pointer, thread_handle. (target_thread_handle): Define. * thread-db.c (find_one_thread, attach_thread): Set thread_handle field in lwp. (thread_db_thread_handle): New function. gdb/ChangeLog: * remote.c (vector): Include. (struct private_thread_info): Add field, thread_handle. (free_private_thread_info): Deallocate storage associated with thread handle. (get_private_info_thread): Initialize `thread_handle' field. (struct thread_item): Add field, thread_handle. (clear_threads_listing_context): Deallocate storage associated with thread handle. (start_thread): Add support for "handle" attribute. (thread_attributes): Add "handle". (remote_get_threads_with_qthreadinfo): Initialize thread_handle field. (remote_update_thread_list): Update thread_handle. (remote_thread_handle_to_thread_info): New function. (init_remote_ops): Initialize to_thread_handle_to_thread_info. --- gdb/ChangeLog | 18 ++++++++++++ gdb/gdbserver/ChangeLog | 14 ++++++++++ gdb/gdbserver/linux-low.c | 5 ++++ gdb/gdbserver/linux-low.h | 5 ++++ gdb/gdbserver/server.c | 10 +++++++ gdb/gdbserver/target.h | 10 +++++++ gdb/gdbserver/thread-db.c | 32 +++++++++++++++++++++ gdb/remote.c | 59 +++++++++++++++++++++++++++++++++++++++ 8 files changed, 153 insertions(+) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index bf9d0871e90..1b1a2b6f896 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,21 @@ +2017-09-21 Kevin Buettner + + * remote.c (vector): Include. + (struct private_thread_info): Add field, thread_handle. + (free_private_thread_info): Deallocate storage associated with + thread handle. + (get_private_info_thread): Initialize `thread_handle' field. + (struct thread_item): Add field, thread_handle. + (clear_threads_listing_context): Deallocate storage associated + with thread handle. + (start_thread): Add support for "handle" attribute. + (thread_attributes): Add "handle". + (remote_get_threads_with_qthreadinfo): Initialize thread_handle + field. + (remote_update_thread_list): Update thread_handle. + (remote_thread_handle_to_thread_info): New function. + (init_remote_ops): Initialize to_thread_handle_to_thread_info. + 2017-09-21 Kevin Buettner * python/py-inferior.c (gdbpy_thread_from_thread_handle): New diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index b075eb3b30f..75d97f05b4c 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,17 @@ +2017-09-21 Kevin Buettner + + * linux-low.h (struct lwp_info): Add new field, thread_handle. + (thread_db_thread_handle): Declare. + * linux-low.c (linux_target_ops): Initialize thread_handle. + * server.c (handle_qxfer_threads_worker): Add support for + "handle" attribute. + * target.h (struct target_ops): Add new function pointer, + thread_handle. + (target_thread_handle): Define. + * thread-db.c (find_one_thread, attach_thread): Set thread_handle + field in lwp. + (thread_db_thread_handle): New function. + 2017-09-21 Kevin Buettner * linux-low.c (handle_extended_wait): Call thread_db_notice_clone(). diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c index a3f9ab9bbcc..c62dc195565 100644 --- a/gdb/gdbserver/linux-low.c +++ b/gdb/gdbserver/linux-low.c @@ -7705,6 +7705,11 @@ static struct target_ops linux_target_ops = { linux_supports_software_single_step, linux_supports_catch_syscall, linux_get_ipa_tdesc_idx, +#if USE_THREAD_DB + thread_db_thread_handle, +#else + NULL, +#endif }; #ifdef HAVE_LINUX_REGSETS diff --git a/gdb/gdbserver/linux-low.h b/gdb/gdbserver/linux-low.h index be27c9229c8..85bb8ca7b28 100644 --- a/gdb/gdbserver/linux-low.h +++ b/gdb/gdbserver/linux-low.h @@ -374,6 +374,9 @@ struct lwp_info /* The thread handle, used for e.g. TLS access. Only valid if THREAD_KNOWN is set. */ td_thrhandle_t th; + + /* The pthread_t handle. */ + thread_t thread_handle; #endif /* Arch-specific additions. */ @@ -416,4 +419,6 @@ int thread_db_look_up_one_symbol (const char *name, CORE_ADDR *addrp); void thread_db_notice_clone (struct process_info *proc, ptid_t lwp); +bool thread_db_thread_handle (ptid_t ptid, gdb_byte **handle, int *handle_len); + extern int have_ptrace_getregset; diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c index a5743b54818..f3eee31052b 100644 --- a/gdb/gdbserver/server.c +++ b/gdb/gdbserver/server.c @@ -1648,6 +1648,9 @@ handle_qxfer_threads_worker (struct inferior_list_entry *inf, void *arg) int core = target_core_of_thread (ptid); char core_s[21]; const char *name = target_thread_name (ptid); + int handle_len; + gdb_byte *handle; + bool handle_status = target_thread_handle (ptid, &handle, &handle_len); write_ptid (ptid_s, ptid); @@ -1662,6 +1665,13 @@ handle_qxfer_threads_worker (struct inferior_list_entry *inf, void *arg) if (name != NULL) buffer_xml_printf (buffer, " name=\"%s\"", name); + if (handle_status) + { + char *handle_s = (char *) alloca (handle_len * 2 + 1); + bin2hex (handle, handle_s, handle_len); + buffer_xml_printf (buffer, " handle=\"%s\"", handle_s); + } + buffer_xml_printf (buffer, "/>\n"); } diff --git a/gdb/gdbserver/target.h b/gdb/gdbserver/target.h index 91cbde16e97..0a3d1db7eb1 100644 --- a/gdb/gdbserver/target.h +++ b/gdb/gdbserver/target.h @@ -475,6 +475,11 @@ struct target_ops /* Return tdesc index for IPA. */ int (*get_ipa_tdesc_idx) (void); + + /* Thread ID to (numeric) thread handle: Return true on success and + false for failure. Return pointer to thread handle via HANDLE + and the handle's length via HANDLE_LEN. */ + bool (*thread_handle) (ptid_t ptid, gdb_byte **handle, int *handle_len); }; extern struct target_ops *the_target; @@ -693,6 +698,11 @@ void done_accessing_memory (void); (the_target->thread_name ? (*the_target->thread_name) (ptid) \ : NULL) +#define target_thread_handle(ptid, handle, handle_len) \ + (the_target->thread_handle ? (*the_target->thread_handle) \ + (ptid, handle, handle_len) \ + : false) + int read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len); int write_inferior_memory (CORE_ADDR memaddr, const unsigned char *myaddr, diff --git a/gdb/gdbserver/thread-db.c b/gdb/gdbserver/thread-db.c index 3d57f318b6e..9156d892fe4 100644 --- a/gdb/gdbserver/thread-db.c +++ b/gdb/gdbserver/thread-db.c @@ -200,6 +200,7 @@ find_one_thread (ptid_t ptid) lwp->thread_known = 1; lwp->th = th; + lwp->thread_handle = ti.ti_tid; return 1; } @@ -231,6 +232,7 @@ attach_thread (const td_thrhandle_t *th_p, td_thrinfo_t *ti_p) gdb_assert (lwp != NULL); lwp->thread_known = 1; lwp->th = *th_p; + lwp->thread_handle = ti_p->ti_tid; return 1; } @@ -439,6 +441,36 @@ thread_db_get_tls_address (struct thread_info *thread, CORE_ADDR offset, return err; } +/* See linux-low.h. */ + +bool +thread_db_thread_handle (ptid_t ptid, gdb_byte **handle, int *handle_len) +{ + struct thread_db *thread_db; + struct lwp_info *lwp; + struct thread_info *thread + = (struct thread_info *) find_inferior_id (&all_threads, ptid); + + if (thread == NULL) + return false; + + thread_db = get_thread_process (thread)->priv->thread_db; + + if (thread_db == NULL) + return false; + + lwp = get_thread_lwp (thread); + + if (!lwp->thread_known && !find_one_thread (thread->entry.id)) + return false; + + gdb_assert (lwp->thread_known); + + *handle = (gdb_byte *) &lwp->thread_handle; + *handle_len = sizeof (lwp->thread_handle); + return true; +} + #ifdef USE_LIBTHREAD_DB_DIRECTLY static int diff --git a/gdb/remote.c b/gdb/remote.c index 0988a250a28..33b0c2a09dc 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -74,6 +74,7 @@ #include #include "common/scoped_restore.h" #include "environ.h" +#include "common/byte-vector.h" /* Temp hacks for tracepoint encoding migration. */ static char *target_buf; @@ -451,6 +452,10 @@ struct private_thread_info char *name; int core; + /* Thread handle, perhaps a pthread_t or thread_t value, stored as a + sequence of bytes. */ + gdb::byte_vector *thread_handle; + /* Whether the target stopped for a breakpoint/watchpoint. */ enum target_stop_reason stop_reason; @@ -482,6 +487,7 @@ free_private_thread_info (struct private_thread_info *info) { xfree (info->extra); xfree (info->name); + delete info->thread_handle; xfree (info); } @@ -1971,6 +1977,7 @@ get_private_info_thread (struct thread_info *thread) priv->last_resume_step = 0; priv->last_resume_sig = GDB_SIGNAL_0; priv->vcont_resumed = 0; + priv->thread_handle = nullptr; } return thread->priv; @@ -2997,6 +3004,10 @@ typedef struct thread_item /* The core the thread was running on. -1 if not known. */ int core; + + /* The thread handle associated with the thread. */ + gdb::byte_vector *thread_handle; + } thread_item_t; DEF_VEC_O(thread_item_t); @@ -3024,6 +3035,7 @@ clear_threads_listing_context (void *p) { xfree (item->extra); xfree (item->name); + delete item->thread_handle; } VEC_free (thread_item_t, context->items); @@ -3062,6 +3074,7 @@ remote_newthread_step (threadref *ref, void *data) item.core = -1; item.name = NULL; item.extra = NULL; + item.thread_handle = nullptr; VEC_safe_push (thread_item_t, context->items, &item); @@ -3132,6 +3145,17 @@ start_thread (struct gdb_xml_parser *parser, attr = xml_find_attribute (attributes, "name"); item.name = attr != NULL ? xstrdup ((const char *) attr->value) : NULL; + attr = xml_find_attribute (attributes, "handle"); + if (attr != NULL) + { + item.thread_handle = new gdb::byte_vector + (strlen ((const char *) attr->value) / 2); + hex2bin ((const char *) attr->value, item.thread_handle->data (), + item.thread_handle->size ()); + } + else + item.thread_handle = nullptr; + item.extra = 0; VEC_safe_push (thread_item_t, data->items, &item); @@ -3153,6 +3177,7 @@ const struct gdb_xml_attribute thread_attributes[] = { { "id", GDB_XML_AF_NONE, NULL, NULL }, { "core", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL }, { "name", GDB_XML_AF_OPTIONAL, NULL, NULL }, + { "handle", GDB_XML_AF_OPTIONAL, NULL, NULL }, { NULL, GDB_XML_AF_NONE, NULL, NULL } }; @@ -3228,6 +3253,7 @@ remote_get_threads_with_qthreadinfo (struct target_ops *ops, item.core = -1; item.name = NULL; item.extra = NULL; + item.thread_handle = nullptr; VEC_safe_push (thread_item_t, context->items, &item); } @@ -3333,6 +3359,8 @@ remote_update_thread_list (struct target_ops *ops) item->extra = NULL; info->name = item->name; item->name = NULL; + info->thread_handle = item->thread_handle; + item->thread_handle = nullptr; } } } @@ -13526,6 +13554,35 @@ remote_execution_direction (struct target_ops *self) return rs->last_resume_exec_dir; } +/* Return pointer to the thread_info struct which corresponds to + THREAD_HANDLE (having length HANDLE_LEN). */ + +static struct thread_info * +remote_thread_handle_to_thread_info (struct target_ops *ops, + const gdb_byte *thread_handle, + int handle_len, + struct inferior *inf) +{ + struct thread_info *tp; + + ALL_NON_EXITED_THREADS (tp) + { + struct private_thread_info *priv = get_private_info_thread (tp); + + if (tp->inf == inf && priv != NULL) + { + if (handle_len != priv->thread_handle->size ()) + error (_("Thread handle size mismatch: %d vs %zu (from remote)"), + handle_len, priv->thread_handle->size ()); + if (memcmp (thread_handle, priv->thread_handle->data (), + handle_len) == 0) + return tp; + } + } + + return NULL; +} + static void init_remote_ops (void) { @@ -13674,6 +13731,8 @@ Specify the serial device it is connected to\n\ remote_ops.to_insert_exec_catchpoint = remote_insert_exec_catchpoint; remote_ops.to_remove_exec_catchpoint = remote_remove_exec_catchpoint; remote_ops.to_execution_direction = remote_execution_direction; + remote_ops.to_thread_handle_to_thread_info = + remote_thread_handle_to_thread_info; } /* Set up the extended remote vector by making a copy of the standard -- 2.30.2