From 6e4879f0eb5ff1985d1040669a69675fadad53f8 Mon Sep 17 00:00:00 2001 From: Markus Metzger Date: Wed, 19 Aug 2015 13:35:52 +0200 Subject: [PATCH] btrace: support to_stop Add support for the to_stop target method to the btrace record target. gdb/ * btrace.h (enum btrace_thread_flag) : New. * record-btrace (record_btrace_resume_thread): Clear BTHR_STOP. (record_btrace_find_thread_to_move): Also accept threads that have BTHR_STOP set. (btrace_step_stopped_on_request, record_btrace_stop): New. (record_btrace_step_thread): Support BTHR_STOP. (record_btrace_wait): Also clear BTHR_STOP when stopping other threads. (init_record_btrace_ops): Initialize to_stop. --- gdb/ChangeLog | 11 ++++++++ gdb/btrace.h | 5 +++- gdb/record-btrace.c | 63 +++++++++++++++++++++++++++++++++++++++------ 3 files changed, 70 insertions(+), 9 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index d01455f10c..f7259ea2a9 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2015-09-18 Markus Metzger + + * btrace.h (enum btrace_thread_flag) : New. + * record-btrace (record_btrace_resume_thread): Clear BTHR_STOP. + (record_btrace_find_thread_to_move): Also accept threads that have + BTHR_STOP set. + (btrace_step_stopped_on_request, record_btrace_stop): New. + (record_btrace_step_thread): Support BTHR_STOP. + (record_btrace_wait): Also clear BTHR_STOP when stopping other threads. + (init_record_btrace_ops): Initialize to_stop. + 2015-09-18 Markus Metzger * record-btrace.c (record_btrace_wait): Replace non_stop check with diff --git a/gdb/btrace.h b/gdb/btrace.h index 756a778fe1..f844df8df9 100644 --- a/gdb/btrace.h +++ b/gdb/btrace.h @@ -240,7 +240,10 @@ enum btrace_thread_flag BTHR_RCONT = (1 << 3), /* The thread is to be moved. */ - BTHR_MOVE = (BTHR_STEP | BTHR_RSTEP | BTHR_CONT | BTHR_RCONT) + BTHR_MOVE = (BTHR_STEP | BTHR_RSTEP | BTHR_CONT | BTHR_RCONT), + + /* The thread is to be stopped. */ + BTHR_STOP = (1 << 4) }; #if defined (HAVE_LIBIPT) diff --git a/gdb/record-btrace.c b/gdb/record-btrace.c index 2d8b20bf96..a9ed4b7e6f 100644 --- a/gdb/record-btrace.c +++ b/gdb/record-btrace.c @@ -1677,6 +1677,8 @@ record_btrace_resume_thread (struct thread_info *tp, /* Fetch the latest branch trace. */ btrace_fetch (tp); + /* A resume request overwrites a preceding stop request. */ + btinfo->flags &= ~BTHR_STOP; btinfo->flags |= flag; } @@ -1872,12 +1874,12 @@ record_btrace_find_thread_to_move (ptid_t ptid) /* First check the parameter thread. */ tp = find_thread_ptid (ptid); - if (tp != NULL && (tp->btrace.flags & BTHR_MOVE) != 0) + if (tp != NULL && (tp->btrace.flags & (BTHR_MOVE | BTHR_STOP)) != 0) return tp; /* Otherwise, find one other thread that has been resumed. */ ALL_NON_EXITED_THREADS (tp) - if ((tp->btrace.flags & BTHR_MOVE) != 0) + if ((tp->btrace.flags & (BTHR_MOVE | BTHR_STOP)) != 0) return tp; return NULL; @@ -1908,6 +1910,20 @@ btrace_step_stopped (void) return status; } +/* Return a target_waitstatus indicating that a thread was stopped as + requested. */ + +static struct target_waitstatus +btrace_step_stopped_on_request (void) +{ + struct target_waitstatus status; + + status.kind = TARGET_WAITKIND_STOPPED; + status.value.sig = GDB_SIGNAL_0; + + return status; +} + /* Clear the record histories. */ static void @@ -1932,23 +1948,27 @@ record_btrace_step_thread (struct thread_info *tp) enum btrace_thread_flag flags; unsigned int steps; - /* We can't step without an execution history. */ - if (btrace_is_empty (tp)) - return btrace_step_no_history (); btinfo = &tp->btrace; replay = btinfo->replay; - flags = btinfo->flags & BTHR_MOVE; - btinfo->flags &= ~BTHR_MOVE; + flags = btinfo->flags & (BTHR_MOVE | BTHR_STOP); + btinfo->flags &= ~(BTHR_MOVE | BTHR_STOP); DEBUG ("stepping %d (%s): %u", tp->num, target_pid_to_str (tp->ptid), flags); + /* We can't step without an execution history. */ + if ((flags & BTHR_MOVE) != 0 && btrace_is_empty (tp)) + return btrace_step_no_history (); + switch (flags) { default: internal_error (__FILE__, __LINE__, _("invalid stepping type.")); + case BTHR_STOP: + return btrace_step_stopped_on_request (); + case BTHR_STEP: /* We're done if we're not replaying. */ if (replay == NULL) @@ -2106,7 +2126,7 @@ record_btrace_wait (struct target_ops *ops, ptid_t ptid, /* Stop all other threads. */ if (!target_is_non_stop_p ()) ALL_NON_EXITED_THREADS (other) - other->btrace.flags &= ~BTHR_MOVE; + other->btrace.flags &= ~(BTHR_MOVE | BTHR_STOP); /* Start record histories anew from the current position. */ record_btrace_clear_histories (&tp->btrace); @@ -2117,6 +2137,32 @@ record_btrace_wait (struct target_ops *ops, ptid_t ptid, return tp->ptid; } +/* The to_stop method of target record-btrace. */ + +static void +record_btrace_stop (struct target_ops *ops, ptid_t ptid) +{ + DEBUG ("stop %s", target_pid_to_str (ptid)); + + /* As long as we're not replaying, just forward the request. */ + if (!record_btrace_is_replaying (ops) && execution_direction != EXEC_REVERSE) + { + ops = ops->beneath; + ops->to_stop (ops, ptid); + } + else + { + struct thread_info *tp; + + ALL_NON_EXITED_THREADS (tp) + if (ptid_match (tp->ptid, ptid)) + { + tp->btrace.flags &= ~BTHR_MOVE; + tp->btrace.flags |= BTHR_STOP; + } + } + } + /* The to_can_execute_reverse method of target record-btrace. */ static int @@ -2350,6 +2396,7 @@ init_record_btrace_ops (void) ops->to_get_tailcall_unwinder = &record_btrace_to_get_tailcall_unwinder; ops->to_resume = record_btrace_resume; ops->to_wait = record_btrace_wait; + ops->to_stop = record_btrace_stop; ops->to_update_thread_list = record_btrace_update_thread_list; ops->to_thread_alive = record_btrace_thread_alive; ops->to_goto_record_begin = record_btrace_goto_begin;