From bec903c96bc5119e357b4ad2cab99bbee7de628e Mon Sep 17 00:00:00 2001 From: Yao Qi Date: Thu, 21 Jul 2016 12:12:18 +0100 Subject: [PATCH] Make reinsert_breakpoint thread specific This patch makes reinsert_breakpoint thread specific, which means we insert and remove reinsert_breakpoint breakpoints for a specific thread. This motivation of this change is that I'll use reinsert_breakpoint for vCont;s on software single step target, so that GDBserver may insert one reinsert_breakpoint for one thread doing step-over, and insert one reinsert_breakpoint for another thread doing vCont;s. After the operation of one thread is finished, GDBserver must remove reinsert_breakpoint for that thread only. On the other hand, reinsert_breakpoint is used for step-over nowadays. GDBserver inserts reinsert_breakpoint, and wait only from the thread doing step-over. After the step-over is done, GDBserver removes the reinsert_breakpoint. If there is still any threads need step-over, do the same again until all threads are finished step-over. In other words, reinsert_breakpoint is globally thread specific, but in an implicit way. It is natural to make it explicitly thread specific. gdb/gdbserver: 2016-07-21 Yao Qi * mem-break.c (struct reinsert_breakpoint) : New field. (set_reinsert_breakpoint): New parameter ptid. Callers updated. (clone_one_breakpoint): Likewise. (delete_reinsert_breakpoints): Change parameter to thread. Callers updated. (has_reinsert_breakpoints): Likewise. (uninsert_reinsert_breakpoints): Likewise. (reinsert_reinsert_breakpoints): Likewise. * mem-break.h (set_reinsert_breakpoint): Update declaration. (delete_reinsert_breakpoints): Likewise. (reinsert_reinsert_breakpoints): Likewise. (uninsert_reinsert_breakpoints): Likewise. (has_reinsert_breakpoints): Likewise. --- gdb/gdbserver/ChangeLog | 16 +++++++++ gdb/gdbserver/linux-low.c | 37 ++++++-------------- gdb/gdbserver/mem-break.c | 71 +++++++++++++++++++++++++++++---------- gdb/gdbserver/mem-break.h | 23 +++++++------ 4 files changed, 92 insertions(+), 55 deletions(-) diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index c440d6686f7..b5e9c9630ae 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,19 @@ +2016-07-21 Yao Qi + + * mem-break.c (struct reinsert_breakpoint) : New field. + (set_reinsert_breakpoint): New parameter ptid. Callers updated. + (clone_one_breakpoint): Likewise. + (delete_reinsert_breakpoints): Change parameter to thread. + Callers updated. + (has_reinsert_breakpoints): Likewise. + (uninsert_reinsert_breakpoints): Likewise. + (reinsert_reinsert_breakpoints): Likewise. + * mem-break.h (set_reinsert_breakpoint): Update declaration. + (delete_reinsert_breakpoints): Likewise. + (reinsert_reinsert_breakpoints): Likewise. + (uninsert_reinsert_breakpoints): Likewise. + (has_reinsert_breakpoints): Likewise. + 2016-07-21 Yao Qi * inferiors.c (get_thread_process): Make parameter const. diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c index 39718c65502..c0b2ac09cdb 100644 --- a/gdb/gdbserver/linux-low.c +++ b/gdb/gdbserver/linux-low.c @@ -549,15 +549,11 @@ handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat) && can_software_single_step () && event == PTRACE_EVENT_VFORK) { - struct thread_info *saved_thread = current_thread; - - current_thread = event_thr; /* If we leave reinsert breakpoints there, child will hit it, so uninsert reinsert breakpoints from parent (and child). Once vfork child is done, reinsert them back to parent. */ - uninsert_reinsert_breakpoints (); - current_thread = saved_thread; + uninsert_reinsert_breakpoints (event_thr); } clone_all_breakpoints (child_thr, event_thr); @@ -592,17 +588,13 @@ handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat) if (event_lwp->bp_reinsert != 0 && can_software_single_step ()) { - struct thread_info *saved_thread = current_thread; - /* The child process is forked and stopped, so it is safe to access its memory without stopping all other threads from other processes. */ - current_thread = child_thr; - delete_reinsert_breakpoints (); - current_thread = saved_thread; + delete_reinsert_breakpoints (child_thr); - gdb_assert (has_reinsert_breakpoints (parent_proc)); - gdb_assert (!has_reinsert_breakpoints (child_proc)); + gdb_assert (has_reinsert_breakpoints (event_thr)); + gdb_assert (!has_reinsert_breakpoints (child_thr)); } /* Report the event. */ @@ -656,14 +648,9 @@ handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat) if (event_lwp->bp_reinsert != 0 && can_software_single_step ()) { - struct thread_info *saved_thread = current_thread; - struct process_info *proc = get_thread_process (event_thr); + reinsert_reinsert_breakpoints (event_thr); - current_thread = event_thr; - reinsert_reinsert_breakpoints (); - current_thread = saved_thread; - - gdb_assert (has_reinsert_breakpoints (proc)); + gdb_assert (has_reinsert_breakpoints (event_thr)); } /* Report the event. */ @@ -2632,11 +2619,9 @@ maybe_hw_step (struct thread_info *thread) return 1; else { - struct process_info *proc = get_thread_process (thread); - /* GDBserver must insert reinsert breakpoint for software single step. */ - gdb_assert (has_reinsert_breakpoints (proc)); + gdb_assert (has_reinsert_breakpoints (thread)); return 0; } } @@ -4224,7 +4209,7 @@ install_software_single_step_breakpoints (struct lwp_info *lwp) next_pcs = (*the_low_target.get_next_pcs) (regcache); for (i = 0; VEC_iterate (CORE_ADDR, next_pcs, i, pc); ++i) - set_reinsert_breakpoint (pc); + set_reinsert_breakpoint (pc, current_ptid); do_cleanups (old_chain); } @@ -4367,7 +4352,7 @@ linux_resume_one_lwp_throw (struct lwp_info *lwp, { /* If the thread isn't doing step-over, there shouldn't be any reinsert breakpoints. */ - gdb_assert (!has_reinsert_breakpoints (proc)); + gdb_assert (!has_reinsert_breakpoints (thread)); } if (fast_tp_collecting == 1) @@ -4860,8 +4845,8 @@ finish_step_over (struct lwp_info *lwp) threads but LWP stopped while doing that. */ if (!can_hardware_single_step ()) { - gdb_assert (has_reinsert_breakpoints (current_process ())); - delete_reinsert_breakpoints (); + gdb_assert (has_reinsert_breakpoints (current_thread)); + delete_reinsert_breakpoints (current_thread); } step_over_bkpt = null_ptid; diff --git a/gdb/gdbserver/mem-break.c b/gdb/gdbserver/mem-break.c index c14219e0795..65ca3f9d3e3 100644 --- a/gdb/gdbserver/mem-break.c +++ b/gdb/gdbserver/mem-break.c @@ -211,6 +211,9 @@ struct other_breakpoint struct reinsert_breakpoint { struct breakpoint base; + + /* Thread the reinsert breakpoint belongs to. */ + ptid_t ptid; }; /* Return the breakpoint size from its kind. */ @@ -1476,17 +1479,21 @@ gdb_breakpoint_here (CORE_ADDR where) } void -set_reinsert_breakpoint (CORE_ADDR stop_at) +set_reinsert_breakpoint (CORE_ADDR stop_at, ptid_t ptid) { - struct breakpoint *bp; + struct reinsert_breakpoint *bp; + + gdb_assert (ptid_get_pid (current_ptid) == ptid_get_pid (ptid)); - bp = set_breakpoint_type_at (reinsert_breakpoint, stop_at, NULL); + bp = (struct reinsert_breakpoint *) set_breakpoint_type_at (reinsert_breakpoint, + stop_at, NULL); + bp->ptid = ptid; } void -delete_reinsert_breakpoints (void) +delete_reinsert_breakpoints (struct thread_info *thread) { - struct process_info *proc = current_process (); + struct process_info *proc = get_thread_process (thread); struct breakpoint *bp, **bp_link; bp = proc->breakpoints; @@ -1494,11 +1501,17 @@ delete_reinsert_breakpoints (void) while (bp) { - if (bp->type == reinsert_breakpoint) + if (bp->type == reinsert_breakpoint + && ptid_equal (((struct reinsert_breakpoint *) bp)->ptid, + ptid_of (thread))) { + struct thread_info *saved_thread = current_thread; + + current_thread = thread; *bp_link = bp->next; release_breakpoint (proc, bp); bp = *bp_link; + current_thread = saved_thread; } else { @@ -1578,21 +1591,29 @@ uninsert_all_breakpoints (void) } void -uninsert_reinsert_breakpoints (void) +uninsert_reinsert_breakpoints (struct thread_info *thread) { - struct process_info *proc = current_process (); + struct process_info *proc = get_thread_process (thread); struct breakpoint *bp; for (bp = proc->breakpoints; bp != NULL; bp = bp->next) { - if (bp->type == reinsert_breakpoint) + if (bp->type == reinsert_breakpoint + && ptid_equal (((struct reinsert_breakpoint *) bp)->ptid, + ptid_of (thread))) { gdb_assert (bp->raw->inserted > 0); /* Only uninsert the raw breakpoint if it only belongs to a reinsert breakpoint. */ if (bp->raw->refcount == 1) - uninsert_raw_breakpoint (bp->raw); + { + struct thread_info *saved_thread = current_thread; + + current_thread = thread; + uninsert_raw_breakpoint (bp->raw); + current_thread = saved_thread; + } } } } @@ -1642,8 +1663,9 @@ reinsert_breakpoints_at (CORE_ADDR pc) } int -has_reinsert_breakpoints (struct process_info *proc) +has_reinsert_breakpoints (struct thread_info *thread) { + struct process_info *proc = get_thread_process (thread); struct breakpoint *bp, **bp_link; bp = proc->breakpoints; @@ -1651,7 +1673,9 @@ has_reinsert_breakpoints (struct process_info *proc) while (bp) { - if (bp->type == reinsert_breakpoint) + if (bp->type == reinsert_breakpoint + && ptid_equal (((struct reinsert_breakpoint *) bp)->ptid, + ptid_of (thread))) return 1; else { @@ -1677,19 +1701,27 @@ reinsert_all_breakpoints (void) } void -reinsert_reinsert_breakpoints (void) +reinsert_reinsert_breakpoints (struct thread_info *thread) { - struct process_info *proc = current_process (); + struct process_info *proc = get_thread_process (thread); struct breakpoint *bp; for (bp = proc->breakpoints; bp != NULL; bp = bp->next) { - if (bp->type == reinsert_breakpoint) + if (bp->type == reinsert_breakpoint + && ptid_equal (((struct reinsert_breakpoint *) bp)->ptid, + ptid_of (thread))) { gdb_assert (bp->raw->inserted > 0); if (bp->raw->refcount == 1) - reinsert_raw_breakpoint (bp->raw); + { + struct thread_info *saved_thread = current_thread; + + current_thread = thread; + reinsert_raw_breakpoint (bp->raw); + current_thread = saved_thread; + } } } } @@ -2113,7 +2145,7 @@ clone_agent_expr (const struct agent_expr *src_ax) /* Deep-copy the contents of one breakpoint to another. */ static struct breakpoint * -clone_one_breakpoint (const struct breakpoint *src) +clone_one_breakpoint (const struct breakpoint *src, ptid_t ptid) { struct breakpoint *dest; struct raw_breakpoint *dest_raw; @@ -2174,6 +2206,9 @@ clone_one_breakpoint (const struct breakpoint *src) = XCNEW (struct reinsert_breakpoint); dest = (struct breakpoint *) reinsert_dest; + /* Since reinsert breakpoint is thread specific, don't copy + thread id from SRC, use ID instead. */ + reinsert_dest->ptid = ptid; } else gdb_assert_not_reached ("unhandled breakpoint type"); @@ -2201,7 +2236,7 @@ clone_all_breakpoints (struct thread_info *child_thread, for (bp = parent_proc->breakpoints; bp != NULL; bp = bp->next) { - new_bkpt = clone_one_breakpoint (bp); + new_bkpt = clone_one_breakpoint (bp, ptid_of (child_thread)); APPEND_TO_LIST (new_list, new_bkpt, bkpt_tail); APPEND_TO_LIST (new_raw_list, new_bkpt->raw, raw_bkpt_tail); } diff --git a/gdb/gdbserver/mem-break.h b/gdb/gdbserver/mem-break.h index d6330035e7a..3322ec569e4 100644 --- a/gdb/gdbserver/mem-break.h +++ b/gdb/gdbserver/mem-break.h @@ -152,31 +152,32 @@ struct breakpoint *set_breakpoint_at (CORE_ADDR where, int delete_breakpoint (struct breakpoint *bkpt); -/* Set a reinsert breakpoint at STOP_AT. */ +/* Set a reinsert breakpoint at STOP_AT for thread represented by + PTID. */ -void set_reinsert_breakpoint (CORE_ADDR stop_at); +void set_reinsert_breakpoint (CORE_ADDR stop_at, ptid_t ptid); -/* Delete all reinsert breakpoints. */ +/* Delete all reinsert breakpoints of THREAD. */ -void delete_reinsert_breakpoints (void); +void delete_reinsert_breakpoints (struct thread_info *thread); -/* Reinsert all reinsert breakpoints of the current process. */ +/* Reinsert all reinsert breakpoints of THREAD. */ -void reinsert_reinsert_breakpoints (void); +void reinsert_reinsert_breakpoints (struct thread_info *thread); -/* Uninsert all reinsert breakpoints of the current process. This - still leaves the reinsert breakpoints in the table. */ +/* Uninsert all reinsert breakpoints of THREAD. This still leaves + the reinsert breakpoints in the table. */ -void uninsert_reinsert_breakpoints (void); +void uninsert_reinsert_breakpoints (struct thread_info *thread); /* Reinsert breakpoints at WHERE (and change their status to inserted). */ void reinsert_breakpoints_at (CORE_ADDR where); -/* Process PROC has reinsert breakpoints or not. */ +/* The THREAD has reinsert breakpoints or not. */ -int has_reinsert_breakpoints (struct process_info *proc); +int has_reinsert_breakpoints (struct thread_info *thread); /* Uninsert breakpoints at WHERE (and change their status to uninserted). This still leaves the breakpoints in the table. */ -- 2.30.2