diff options
| -rw-r--r-- | gdb/breakpoint.c | 2 | ||||
| -rw-r--r-- | gdb/gdbthread.h | 3 | ||||
| -rw-r--r-- | gdb/infcall.c | 6 | ||||
| -rw-r--r-- | gdb/infrun.c | 64 | ||||
| -rw-r--r-- | gdb/infrun.h | 3 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.c | 135 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.exp | 174 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.c | 89 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.exp | 235 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.c | 139 | ||||
| -rw-r--r-- | gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.exp | 117 |
11 files changed, 952 insertions, 15 deletions
diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c index 102bd7f..39c1310 100644 --- a/gdb/breakpoint.c +++ b/gdb/breakpoint.c @@ -5665,6 +5665,8 @@ bpstat_check_breakpoint_conditions (bpstat *bs, thread_info *thread) { try { + scoped_restore reset_in_cond_eval + = make_scoped_restore (&thread->control.in_cond_eval, true); condition_result = breakpoint_cond_eval (cond); } catch (const gdb_exception_error &ex) diff --git a/gdb/gdbthread.h b/gdb/gdbthread.h index 11c553a..73f6895 100644 --- a/gdb/gdbthread.h +++ b/gdb/gdbthread.h @@ -173,6 +173,9 @@ struct thread_control_state command. This is used to decide whether "set scheduler-locking step" behaves like "on" or "off". */ int stepping_command = 0; + + /* True if the thread is evaluating a BP condition. */ + bool in_cond_eval = false; }; /* Inferior thread specific part of `struct infcall_suspend_state'. */ diff --git a/gdb/infcall.c b/gdb/infcall.c index 145ce25..bfcac20 100644 --- a/gdb/infcall.c +++ b/gdb/infcall.c @@ -672,6 +672,12 @@ run_inferior_call (std::unique_ptr<call_thread_fsm> sm, proceed (real_pc, GDB_SIGNAL_0); + /* Enable commit resume, but pass true for the force flag. This + ensures any thread we set running in proceed will actually be + committed to the target, even if some other thread in the current + target has a pending event. */ + scoped_enable_commit_resumed enable ("infcall", true); + infrun_debug_show_threads ("non-exited threads after proceed for inferior-call", all_non_exited_threads ()); diff --git a/gdb/infrun.c b/gdb/infrun.c index e0e0ba3..b06972b 100644 --- a/gdb/infrun.c +++ b/gdb/infrun.c @@ -2406,6 +2406,14 @@ user_visible_resume_ptid (int step) mode. */ resume_ptid = inferior_ptid; } + else if (inferior_ptid != null_ptid + && inferior_thread ()->control.in_cond_eval) + { + /* The inferior thread is evaluating a BP condition. Other threads + might be stopped or running and we do not want to change their + state, thus, resume only the current thread. */ + resume_ptid = inferior_ptid; + } else if (!sched_multi && target_supports_multi_process ()) { /* Resume all threads of the current process (and none of other @@ -3201,12 +3209,24 @@ schedlock_applies (struct thread_info *tp) execution_direction))); } -/* Set process_stratum_target::COMMIT_RESUMED_STATE in all target - stacks that have threads executing and don't have threads with - pending events. */ +/* When FORCE_P is false, set process_stratum_target::COMMIT_RESUMED_STATE + in all target stacks that have threads executing and don't have threads + with pending events. + + When FORCE_P is true, set process_stratum_target::COMMIT_RESUMED_STATE + in all target stacks that have threads executing regardless of whether + there are pending events or not. + + Passing FORCE_P as false makes sense when GDB is going to wait for + events from all threads and will therefore spot the pending events. + However, if GDB is only going to wait for events from select threads + (i.e. when performing an inferior call) then a pending event on some + other thread will not be spotted, and if we fail to commit the resume + state for the thread performing the inferior call, then the inferior + call will never complete (or even start). */ static void -maybe_set_commit_resumed_all_targets () +maybe_set_commit_resumed_all_targets (bool force_p) { scoped_restore_current_thread restore_thread; @@ -3235,7 +3255,7 @@ maybe_set_commit_resumed_all_targets () status to report, handle it before requiring the target to commit its resumed threads: handling the status might lead to resuming more threads. */ - if (proc_target->has_resumed_with_pending_wait_status ()) + if (!force_p && proc_target->has_resumed_with_pending_wait_status ()) { infrun_debug_printf ("not requesting commit-resumed for target %s, a" " thread has a pending waitstatus", @@ -3245,7 +3265,7 @@ maybe_set_commit_resumed_all_targets () switch_to_inferior_no_thread (inf); - if (target_has_pending_events ()) + if (!force_p && target_has_pending_events ()) { infrun_debug_printf ("not requesting commit-resumed for target %s, " "target has pending events", @@ -3338,7 +3358,7 @@ scoped_disable_commit_resumed::reset () { /* This is the outermost instance, re-enable COMMIT_RESUMED_STATE on the targets where it's possible. */ - maybe_set_commit_resumed_all_targets (); + maybe_set_commit_resumed_all_targets (false); } else { @@ -3371,7 +3391,7 @@ scoped_disable_commit_resumed::reset_and_commit () /* See infrun.h. */ scoped_enable_commit_resumed::scoped_enable_commit_resumed - (const char *reason) + (const char *reason, bool force_p) : m_reason (reason), m_prev_enable_commit_resumed (enable_commit_resumed) { @@ -3383,7 +3403,7 @@ scoped_enable_commit_resumed::scoped_enable_commit_resumed /* Re-enable COMMIT_RESUMED_STATE on the targets where it's possible. */ - maybe_set_commit_resumed_all_targets (); + maybe_set_commit_resumed_all_targets (force_p); maybe_call_commit_resumed_all_targets (); } @@ -4136,10 +4156,11 @@ do_target_wait (ptid_t wait_ptid, execution_control_state *ecs, polling the rest of the inferior list starting from that one in a circular fashion until the whole list is polled once. */ - auto inferior_matches = [&wait_ptid] (inferior *inf) + ptid_t wait_ptid_pid {wait_ptid.pid ()}; + auto inferior_matches = [&wait_ptid_pid] (inferior *inf) { return (inf->process_target () != nullptr - && ptid_t (inf->pid).matches (wait_ptid)); + && ptid_t (inf->pid).matches (wait_ptid_pid)); }; /* First see how many matching inferiors we have. */ @@ -4628,7 +4649,17 @@ fetch_inferior_event () the event. */ scoped_disable_commit_resumed disable_commit_resumed ("handling event"); - if (!do_target_wait (minus_one_ptid, &ecs, TARGET_WNOHANG)) + /* Is the current thread performing an inferior function call as part + of a breakpoint condition evaluation? */ + bool in_cond_eval = (inferior_ptid != null_ptid + && inferior_thread ()->control.in_cond_eval); + + /* If the thread is in the middle of the condition evaluation, wait for + an event from the current thread. Otherwise, wait for an event from + any thread. */ + ptid_t waiton_ptid = in_cond_eval ? inferior_ptid : minus_one_ptid; + + if (!do_target_wait (waiton_ptid, &ecs, TARGET_WNOHANG)) { infrun_debug_printf ("do_target_wait returned no event"); disable_commit_resumed.reset_and_commit (); @@ -4686,7 +4717,12 @@ fetch_inferior_event () bool should_notify_stop = true; bool proceeded = false; - stop_all_threads_if_all_stop_mode (); + /* If the thread that stopped just completed an inferior + function call as part of a condition evaluation, then we + don't want to stop all the other threads. */ + if (ecs.event_thread == nullptr + || !ecs.event_thread->control.in_cond_eval) + stop_all_threads_if_all_stop_mode (); clean_up_just_stopped_threads_fsms (&ecs); @@ -4713,7 +4749,7 @@ fetch_inferior_event () proceeded = normal_stop (); } - if (!proceeded) + if (!proceeded && !in_cond_eval) { inferior_event_handler (INF_EXEC_COMPLETE); cmd_done = 1; diff --git a/gdb/infrun.h b/gdb/infrun.h index 6339fd9..5f83ca2 100644 --- a/gdb/infrun.h +++ b/gdb/infrun.h @@ -406,7 +406,8 @@ extern void maybe_call_commit_resumed_all_targets (); struct scoped_enable_commit_resumed { - explicit scoped_enable_commit_resumed (const char *reason); + explicit scoped_enable_commit_resumed (const char *reason, + bool force_p = false); ~scoped_enable_commit_resumed (); DISABLE_COPY_AND_ASSIGN (scoped_enable_commit_resumed); diff --git a/gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.c b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.c new file mode 100644 index 0000000..38a5bc2 --- /dev/null +++ b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.c @@ -0,0 +1,135 @@ +/* Copyright 2022-2024 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include <pthread.h> +#include <unistd.h> +#include <stdlib.h> +#include <sched.h> + +#define NUM_THREADS 2 + +pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; + +/* Some global variables to poke, just for something to do. */ +volatile int global_var_0 = 0; +volatile int global_var_1 = 0; + +/* This flag is updated from GDB. */ +volatile int raise_signal = 0; + +/* Implement the breakpoint condition function. Release the other thread + and try to give the other thread a chance to run. Then return ANSWER. */ +int +condition_core_func (int answer) +{ + /* This unlock should release the other thread. */ + if (pthread_mutex_unlock (&mutex) != 0) + abort (); + + /* And this yield and sleep should (hopefully) give the other thread a + chance to run. This isn't guaranteed of course, but once the other + thread does run it should hit a breakpoint, which GDB should + (temporarily) ignore, so there's no easy way for us to know the other + thread has done what it needs to, thus, yielding and sleeping is the + best we can do. */ + sched_yield (); + sleep (2); + + return answer; +} + +void +stop_marker () +{ + int a = 100; /* Final breakpoint here. */ +} + +/* A breakpoint condition function that always returns true. */ +int +condition_true_func () +{ + return condition_core_func (1); +} + +/* A breakpoint condition function that always returns false. */ +int +condition_false_func () +{ + return condition_core_func (0); +} + +void * +worker_func (void *arg) +{ + volatile int *ptr = 0; + int tid = *((int *) arg); + + switch (tid) + { + case 0: + global_var_0 = 11; /* First thread breakpoint. */ + break; + + case 1: + if (pthread_mutex_lock (&mutex) != 0) + abort (); + if (raise_signal) + global_var_1 = *ptr; /* Signal here. */ + else + global_var_1 = 99; /* Other thread breakpoint. */ + break; + + default: + abort (); + } + + return NULL; +} + +int +main () +{ + pthread_t threads[NUM_THREADS]; + int args[NUM_THREADS]; + + /* Set an alarm, just in case the test deadlocks. */ + alarm (300); + + /* We want the mutex to start locked. */ + if (pthread_mutex_lock (&mutex) != 0) + abort (); + + for (int i = 0; i < NUM_THREADS; i++) + { + args[i] = i; + pthread_create (&threads[i], NULL, worker_func, &args[i]); + } + + for (int i = 0; i < NUM_THREADS; i++) + { + void *retval; + pthread_join (threads[i], &retval); + } + + /* Unlock once we're done, just for cleanliness. */ + if (pthread_mutex_unlock (&mutex) != 0) + abort (); + + stop_marker (); + + return 0; +} diff --git a/gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.exp b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.exp new file mode 100644 index 0000000..b5c0d84 --- /dev/null +++ b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-other-thread-event.exp @@ -0,0 +1,174 @@ +# Copyright 2022-2024 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# Test for conditional breakpoints where the breakpoint condition includes +# an inferior function call. +# +# The tests in this script are testing what happens when an event arrives in +# another thread while GDB is waiting for the inferior function call (in the +# breakpoint condition) to finish. +# +# The expectation is that GDB will queue events for other threads and wait +# for the inferior function call to complete, if the condition is true, then +# the conditional breakpoint should be reported first. The other thread +# event should of course, not get lost, and should be reported as soon as +# the user tries to continue the inferior. +# +# If the conditional breakpoint ends up not being taken (the condition is +# false), then the other thread event should be reported immediately. +# +# This script tests what happens when the other thread event is (a) the +# other thread hitting a breakpoint, and (b) the other thread taking a +# signal (SIGSEGV in this case). + +standard_testfile + +if { [build_executable "failed to prepare" ${binfile} "${srcfile}" \ + {debug pthreads}] == -1 } { + return +} + +set cond_bp_line [gdb_get_line_number "First thread breakpoint"] +set other_bp_line [gdb_get_line_number "Other thread breakpoint"] +set final_bp_line [gdb_get_line_number "Final breakpoint here"] +set signal_line [gdb_get_line_number "Signal here"] + +# Start GDB based on TARGET_ASYNC and TARGET_NON_STOP, and then runto main. +proc start_gdb_and_runto_main { target_async target_non_stop } { + save_vars { ::GDBFLAGS } { + append ::GDBFLAGS \ + " -ex \"maint set target-non-stop $target_non_stop\"" + append ::GDBFLAGS \ + " -ex \"maintenance set target-async ${target_async}\"" + + clean_restart ${::binfile} + } + + if { ![runto_main] } { + return -1 + } + + return 0 +} + +# Run a test of GDB's conditional breakpoints, where the conditions include +# inferior function calls. While the inferior function call is executing +# another thread will hit a breakpoint (when OTHER_THREAD_SIGNAL is false), +# or receive a signal (when OTHER_THREAD_SIGNAL is true). GDB should report +# the conditional breakpoint first (if the condition is true), and then +# report the second thread event once the inferior is continued again. +# +# When STOP_AT_COND is true then the conditional breakpoint will have a +# condition that evaluates to true (and GDB will stop at the breakpoint), +# otherwise, the condition will evaluate to false (and GDB will not stop at +# the breakpoint). +proc run_condition_test { stop_at_cond other_thread_signal \ + target_async target_non_stop } { + if { [start_gdb_and_runto_main $target_async \ + $target_non_stop] == -1 } { + return + } + + # Setup the conditional breakpoint. + if { $stop_at_cond } { + set cond_func "condition_true_func" + } else { + set cond_func "condition_false_func" + } + gdb_breakpoint \ + "${::srcfile}:${::cond_bp_line} if (${cond_func} ())" + set cond_bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number for conditional breakpoint"] + + if { $other_thread_signal } { + # Arrange for the other thread to raise a signal while GDB is + # evaluating the breakpoint condition. + gdb_test_no_output "set raise_signal = 1" + } else { + # And a breakpoint that will be hit by another thread only once the + # breakpoint condition starts to be evaluated. + gdb_breakpoint "${::srcfile}:${::other_bp_line}" + set other_bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number for other breakpoint"] + } + + # A final breakpoint once the test has completed. + gdb_breakpoint "${::srcfile}:${::final_bp_line}" + set final_bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number for final breakpoint"] + + if { $stop_at_cond } { + # Continue. The first breakpoint we hit should be the conditional + # breakpoint. The other thread will have hit its breakpoint, but + # that will have been deferred until the conditional breakpoint is + # reported. + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "" \ + "Thread ${::decimal} \"\[^\"\r\n\]+\" hit Breakpoint ${cond_bp_num}, worker_func \[^\r\n\]+:${::cond_bp_line}" \ + "${::decimal}\\s+\[^\r\n\]+First thread breakpoint\[^\r\n\]+"] \ + "hit the conditional breakpoint" + } + + if { $other_thread_signal } { + # Now continue again, the other thread will now report that it + # received a signal. + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "Thread ${::decimal} \"\[^\"\r\n\]+\" received signal SIGSEGV, Segmentation fault\\." \ + "\\\[Switching to Thread \[^\r\n\]+\\\]" \ + "${::hex} in worker_func \[^\r\n\]+:${::signal_line}" \ + "${::decimal}\\s+\[^\r\n\]+Signal here\[^\r\n\]+"] \ + "received signal in other thread" + } else { + # Now continue again, the other thread will now report its + # breakpoint. + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "" \ + "Thread ${::decimal} \"\[^\"\r\n\]+\" hit Breakpoint ${other_bp_num}, worker_func \[^\r\n\]+:${::other_bp_line}" \ + "${::decimal}\\s+\[^\r\n\]+Other thread breakpoint\[^\r\n\]+"] \ + "hit the breakpoint in other thread" + + # Run to the stop marker. + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "" \ + "Thread ${::decimal} \"\[^\"\r\n\]+\" hit Breakpoint ${final_bp_num}, stop_marker \[^\r\n\]+:${::final_bp_line}" \ + "${::decimal}\\s+\[^\r\n\]+Final breakpoint here\[^\r\n\]+"] \ + "hit the final breakpoint" + } + + gdb_exit +} + +foreach_with_prefix target_async { "on" "off" } { + foreach_with_prefix target_non_stop { "on" "off" } { + foreach_with_prefix other_thread_signal { true false } { + foreach_with_prefix stop_at_cond { true false } { + run_condition_test $stop_at_cond $other_thread_signal \ + $target_async $target_non_stop + } + } + } +} diff --git a/gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.c b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.c new file mode 100644 index 0000000..2e23f12 --- /dev/null +++ b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.c @@ -0,0 +1,89 @@ +/* Copyright 2022-2024 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include <pthread.h> +#include <unistd.h> + +#define NUM_THREADS 3 + +int +is_matching_tid (int *tid_ptr, int tid_value) +{ + return *tid_ptr == tid_value; +} + +int +return_true () +{ + return 1; +} + +int +return_false () +{ + return 0; +} + +int +function_that_segfaults () +{ + int *p = 0; + *p = 1; /* Segfault happens here. */ +} + +int +function_with_breakpoint () +{ + return 1; /* Nested breakpoint. */ +} + +void * +worker_func (void *arg) +{ + int a = 42; /* Breakpoint here. */ +} + +void +stop_marker () +{ + int b = 99; /* Stop marker. */ +} + +int +main () +{ + pthread_t threads[NUM_THREADS]; + int args[NUM_THREADS]; + + alarm (300); + + for (int i = 0; i < NUM_THREADS; i++) + { + args[i] = i; + pthread_create (&threads[i], NULL, worker_func, &args[i]); + } + + for (int i = 0; i < NUM_THREADS; i++) + { + void *retval; + pthread_join (threads[i], &retval); + } + + stop_marker (); + + return 0; +} diff --git a/gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.exp b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.exp new file mode 100644 index 0000000..d6069eba --- /dev/null +++ b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-simple.exp @@ -0,0 +1,235 @@ +# Copyright 2022-2024 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# Some simple tests of inferior function calls from breakpoint +# conditions, in multi-threaded inferiors. +# +# This test sets up a multi-threaded inferior, and places a breakpoint +# at a location that many of the threads will reach. We repeat the +# test with different conditions, sometimes a single thread should +# stop at the breakpoint, sometimes multiple threads should stop, and +# sometimes no threads should stop. + +standard_testfile + +if { [build_executable "failed to prepare" ${binfile} "${srcfile}" \ + {debug pthreads}] == -1 } { + return +} + +set cond_bp_line [gdb_get_line_number "Breakpoint here"] +set stop_bp_line [gdb_get_line_number "Stop marker"] +set nested_bp_line [gdb_get_line_number "Nested breakpoint"] +set segv_line [gdb_get_line_number "Segfault happens here"] + +# Start GDB based on TARGET_ASYNC and TARGET_NON_STOP, and then runto main. +proc start_gdb_and_runto_main { target_async target_non_stop } { + save_vars { ::GDBFLAGS } { + append ::GDBFLAGS \ + " -ex \"maint set target-non-stop $target_non_stop\"" + append ::GDBFLAGS \ + " -ex \"maintenance set target-async ${target_async}\"" + + clean_restart ${::binfile} + } + + if { ![runto_main] } { + return -1 + } + + return 0 +} + +# Run a test of GDB's conditional breakpoints, where the conditions include +# inferior function calls. +# +# CONDITION is the expression to be used as the breakpoint condition. +# +# N_EXPECTED_HITS is the number of threads that we expect to stop due to +# CONDITON. +# +# MESSAGE is used as a test name prefix. +proc run_condition_test { message n_expected_hits condition \ + target_async target_non_stop } { + with_test_prefix $message { + + if { [start_gdb_and_runto_main $target_async \ + $target_non_stop] == -1 } { + return + } + + # Use this convenience variable to track how often the + # breakpoint condition has been evaluated. This should be + # once per thread. + gdb_test "set \$n_cond_eval = 0" + + # Setup the conditional breakpoint. + gdb_breakpoint \ + "${::srcfile}:${::cond_bp_line} if ((++\$n_cond_eval) && (${condition}))" + + # And a breakpoint that we hit when the test is over, this one is + # not conditional. Only the main thread gets here once all the + # other threads have finished. + gdb_breakpoint "${::srcfile}:${::stop_bp_line}" + + # The number of times we stop at the conditional breakpoint. + set n_hit_condition 0 + + # Now keep 'continue'-ing GDB until all the threads have finished + # and we reach the stop_marker breakpoint. + gdb_test_multiple "continue" "spot all breakpoint hits" { + -re " worker_func \[^\r\n\]+${::srcfile}:${::cond_bp_line}\r\n${::decimal}\\s+\[^\r\n\]+Breakpoint here\[^\r\n\]+\r\n${::gdb_prompt} $" { + incr n_hit_condition + send_gdb "continue\n" + exp_continue + } + + -re " stop_marker \[^\r\n\]+${::srcfile}:${::stop_bp_line}\r\n${::decimal}\\s+\[^\r\n\]+Stop marker\[^\r\n\]+\r\n${::gdb_prompt} $" { + pass $gdb_test_name + } + } + + gdb_assert { $n_hit_condition == $n_expected_hits } \ + "stopped at breakpoint the expected number of times" + + # Ensure the breakpoint condition was evaluated once per thread. + gdb_test "print \$n_cond_eval" "= 3" \ + "condition was evaluated in each thread" + } +} + +# Check that after handling a conditional breakpoint (where the condition +# includes an inferior call), it is still possible to kill the running +# inferior, and then restart the inferior. +# +# At once point doing this would result in GDB giving an assertion error. +proc_with_prefix run_kill_and_restart_test { target_async target_non_stop } { + # This test relies on the 'start' command, which is not possible with + # the plain 'remote' target. + if { [target_info gdb_protocol] == "remote" } { + return + } + + if { [start_gdb_and_runto_main $target_async \ + $target_non_stop] == -1 } { + return + } + + # Setup the conditional breakpoint. + gdb_breakpoint \ + "${::srcfile}:${::cond_bp_line} if (is_matching_tid (arg, 1))" + gdb_continue_to_breakpoint "worker_func" + + # Now kill the program being debugged. + gdb_test "kill" "" "kill process" \ + "Kill the program being debugged.*y or n. $" "y" + + # Check we can restart the inferior. At one point this would trigger an + # assertion. + gdb_start_cmd +} + +# Create a conditional breakpoint which includes a call to a function that +# segfaults. Run GDB and check what happens when the inferior segfaults +# during the inferior call. +proc_with_prefix run_bp_cond_segfaults { target_async target_non_stop } { + if { [start_gdb_and_runto_main $target_async \ + $target_non_stop] == -1 } { + return + } + + # This test relies on the inferior segfaulting when trying to + # access address zero. + if { [is_address_zero_readable] } { + return + } + + # Setup the conditional breakpoint, include a call to + # 'function_that_segfaults', which triggers the segfault. + gdb_breakpoint \ + "${::srcfile}:${::cond_bp_line} if (is_matching_tid (arg, 0) && function_that_segfaults ())" + set bp_1_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number of conditional breakpoint"] + + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "Thread ${::decimal} \"infcall-from-bp\" received signal SIGSEGV, Segmentation fault\\." \ + "${::hex} in function_that_segfaults \\(\\) at \[^\r\n\]+:${::segv_line}" \ + "${::decimal}\\s+\[^\r\n\]+Segfault happens here\[^\r\n\]+" \ + "Error in testing condition for breakpoint ${bp_1_num}:" \ + "The program being debugged was signaled while in a function called from GDB\\." \ + "GDB remains in the frame where the signal was received\\." \ + "To change this behavior use \"set unwindonsignal on\"\\." \ + "Evaluation of the expression containing the function" \ + "\\(function_that_segfaults\\) will be abandoned\\." \ + "When the function is done executing, GDB will silently stop\\."] +} + +# Create a conditional breakpoint which includes a call to a function that +# itself has a breakpoint set within it. Run GDB and check what happens +# when GDB hits the nested breakpoint. +proc_with_prefix run_bp_cond_hits_breakpoint { target_async target_non_stop } { + if { [start_gdb_and_runto_main $target_async \ + $target_non_stop] == -1 } { + return + } + + # Setup the conditional breakpoint, include a call to + # 'function_with_breakpoint' in which we will shortly place a + # breakpoint. + gdb_breakpoint \ + "${::srcfile}:${::cond_bp_line} if (is_matching_tid (arg, 0) && function_with_breakpoint ())" + set bp_1_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number of conditional breakpoint"] + + gdb_breakpoint "${::srcfile}:${::nested_bp_line}" + set bp_2_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number of nested breakpoint"] + + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "Thread ${::decimal} \"infcall-from-bp\" hit Breakpoint ${bp_2_num}, function_with_breakpoint \\(\\) at \[^\r\n\]+:${::nested_bp_line}" \ + "${::decimal}\\s+\[^\r\n\]+Nested breakpoint\[^\r\n\]+" \ + "Error in testing condition for breakpoint ${bp_1_num}:" \ + "The program being debugged stopped while in a function called from GDB\\." \ + "Evaluation of the expression containing the function" \ + "\\(function_with_breakpoint\\) will be abandoned\\." \ + "When the function is done executing, GDB will silently stop\\."] +} + +foreach_with_prefix target_async { "on" "off" } { + foreach_with_prefix target_non_stop { "on" "off" } { + run_condition_test "exactly one thread is hit" \ + 1 "is_matching_tid (arg, 1)" \ + $target_async $target_non_stop + run_condition_test "exactly two threads are hit" \ + 2 "(is_matching_tid (arg, 0) || is_matching_tid (arg, 2))" \ + $target_async $target_non_stop + run_condition_test "all three threads are hit" \ + 3 "return_true ()" \ + $target_async $target_non_stop + run_condition_test "no thread is hit" \ + 0 "return_false ()" \ + $target_async $target_non_stop + + run_kill_and_restart_test $target_async $target_non_stop + run_bp_cond_segfaults $target_async $target_non_stop + run_bp_cond_hits_breakpoint $target_async $target_non_stop + } +} diff --git a/gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.c b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.c new file mode 100644 index 0000000..0b045f8 --- /dev/null +++ b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.c @@ -0,0 +1,139 @@ +/* Copyright 2022-2024 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include <pthread.h> +#include <unistd.h> +#include <semaphore.h> +#include <stdlib.h> + +#define NUM_THREADS 5 + +/* Semaphores, used to track when threads have started, and to control + when the threads finish. */ +sem_t startup_semaphore; +sem_t finish_semaphore; + +/* Mutex to control when the first worker thread hit a breakpoint + location. */ +pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; + +/* Global variable to poke, just so threads have something to do. */ +volatile int global_var = 0; + +int +return_true () +{ + return 1; +} + +int +return_false () +{ + return 0; +} + +void * +worker_func (void *arg) +{ + int tid = *((int *) arg); + + switch (tid) + { + case 0: + /* Wait for MUTEX to become available, then pass through the + conditional breakpoint location. */ + if (pthread_mutex_lock (&mutex) != 0) + abort (); + global_var = 99; /* Conditional breakpoint here. */ + if (pthread_mutex_unlock (&mutex) != 0) + abort (); + break; + + default: + /* Notify the main thread that the thread has started, then wait for + the main thread to tell us to finish. */ + sem_post (&startup_semaphore); + if (sem_wait (&finish_semaphore) != 0) + abort (); + break; + } +} + +void +stop_marker () +{ + global_var = 99; /* Stop marker. */ +} + +int +main () +{ + pthread_t threads[NUM_THREADS]; + int args[NUM_THREADS]; + void *retval; + + /* An alarm, just in case the thread deadlocks. */ + alarm (300); + + /* Semaphore initialization. */ + if (sem_init (&startup_semaphore, 0, 0) != 0) + abort (); + if (sem_init (&finish_semaphore, 0, 0) != 0) + abort (); + + /* Lock MUTEX, this prevents the first worker thread from rushing ahead. */ + if (pthread_mutex_lock (&mutex) != 0) + abort (); + + /* Worker thread creation. */ + for (int i = 0; i < NUM_THREADS; i++) + { + args[i] = i; + pthread_create (&threads[i], NULL, worker_func, &args[i]); + } + + /* Wait for every thread (other than the first) to tell us it has started + up. */ + for (int i = 1; i < NUM_THREADS; i++) + { + if (sem_wait (&startup_semaphore) != 0) + abort (); + } + + /* Unlock the first thread so it can proceed. */ + if (pthread_mutex_unlock (&mutex) != 0) + abort (); + + /* Wait for the first thread only. */ + pthread_join (threads[0], &retval); + + /* Now post FINISH_SEMAPHORE to allow all the other threads to finish. */ + for (int i = 1; i < NUM_THREADS; i++) + sem_post (&finish_semaphore); + + /* Now wait for the remaining threads to complete. */ + for (int i = 1; i < NUM_THREADS; i++) + pthread_join (threads[i], &retval); + + /* Semaphore cleanup. */ + sem_destroy (&finish_semaphore); + sem_destroy (&startup_semaphore); + + stop_marker (); + + return 0; +} diff --git a/gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.exp b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.exp new file mode 100644 index 0000000..2c3623e --- /dev/null +++ b/gdb/testsuite/gdb.threads/infcall-from-bp-cond-single.exp @@ -0,0 +1,117 @@ +# Copyright 2022-2024 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# This test reprocuces bug gdb/28942, performing an inferior function +# call from a breakpoint condition in a multi-threaded inferior. +# +# The important part of this test is that, when the conditional +# breakpoint is hit, and the condition (which includes an inferior +# function call) is evaluated, the other threads are running. + +standard_testfile + +if { [build_executable "failed to prepare" ${binfile} "${srcfile}" \ + {debug pthreads}] == -1 } { + return +} + +set cond_bp_line [gdb_get_line_number "Conditional breakpoint here"] +set final_bp_line [gdb_get_line_number "Stop marker"] + +# Start GDB based on TARGET_ASYNC and TARGET_NON_STOP, and then runto main. +proc start_gdb_and_runto_main { target_async target_non_stop } { + save_vars { ::GDBFLAGS } { + append ::GDBFLAGS \ + " -ex \"maint set target-non-stop $target_non_stop\"" + append ::GDBFLAGS \ + " -ex \"maintenance set target-async ${target_async}\"" + + clean_restart ${::binfile} + } + + if { ![runto_main] } { + return -1 + } + + return 0 +} + +# Run a test of GDB's conditional breakpoints, where the conditions include +# inferior function calls. +# +# TARGET_ASYNC and TARGET_NON_STOP are used when starting up GDB. +# +# When STOP_AT_COND is true the breakpoint condtion will evaluate to +# true, and GDB will stop at the breakpoint. Otherwise, the +# breakpoint condition will evaluate to false and GDB will not stop at +# the breakpoint. +proc run_condition_test { stop_at_cond \ + target_async target_non_stop } { + if { [start_gdb_and_runto_main $target_async \ + $target_non_stop] == -1 } { + return + } + + # Setup the conditional breakpoint. + if { $stop_at_cond } { + set cond_func "return_true" + } else { + set cond_func "return_false" + } + gdb_breakpoint \ + "${::srcfile}:${::cond_bp_line} if (${cond_func} ())" + set cond_bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number for conditional breakpoint"] + + # And a breakpoint that we hit when the test is over, this one is + # not conditional. + gdb_breakpoint "${::srcfile}:${::final_bp_line}" + set final_bp_num [get_integer_valueof "\$bpnum" "*UNKNOWN*" \ + "get number for final breakpoint"] + + if { $stop_at_cond } { + # Continue. The first breakpoint we hit should be the conditional + # breakpoint. The other thread will have hit its breakpoint, but + # that will have been deferred until the conditional breakpoint is + # reported. + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "" \ + "Thread ${::decimal} \"\[^\"\r\n\]+\" hit Breakpoint ${cond_bp_num}, worker_func \[^\r\n\]+:${::cond_bp_line}" \ + "${::decimal}\\s+\[^\r\n\]+Conditional breakpoint here\[^\r\n\]+"] \ + "hit the conditional breakpoint" + } + + # Run to the stop marker. + gdb_test "continue" \ + [multi_line \ + "Continuing\\." \ + ".*" \ + "" \ + "Thread ${::decimal} \"\[^\"\r\n\]+\" hit Breakpoint ${final_bp_num}, stop_marker \[^\r\n\]+:${::final_bp_line}" \ + "${::decimal}\\s+\[^\r\n\]+Stop marker\[^\r\n\]+"] \ + "hit the final breakpoint" +} + +foreach_with_prefix target_async { "on" "off" } { + foreach_with_prefix target_non_stop { "on" "off" } { + foreach_with_prefix stop_at_cond { true false } { + run_condition_test $stop_at_cond \ + $target_async $target_non_stop + } + } +} |