From 122f36efc10da1ff5133220193fdbb83062db614 Mon Sep 17 00:00:00 2001 From: Pedro Alves Date: Mon, 19 Mar 2012 14:33:35 +0000 Subject: [PATCH] 2012-03-19 Pedro Alves Jan Kratochvil * server.c (cont_thread, general_thread): Add describing comments. (start_inferior): Clear `cont_thread'. (handle_v_cont): Don't set `cont_thread' if resuming all threads of a process. --- gdb/gdbserver/ChangeLog | 8 ++++++++ gdb/gdbserver/server.c | 24 ++++++++++++++++++++++-- 2 files changed, 30 insertions(+), 2 deletions(-) diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 61607a6..91b12e0 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,11 @@ +2012-03-19 Pedro Alves + Jan Kratochvil + + * server.c (cont_thread, general_thread): Add describing comments. + (start_inferior): Clear `cont_thread'. + (handle_v_cont): Don't set `cont_thread' if resuming all threads + of a process. + 2012-03-15 Yao Qi * tracepoint.c (install_tracepoint): Move duplicated tracepoint diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c index 3c97dbd..a4e9e57 100644 --- a/gdb/gdbserver/server.c +++ b/gdb/gdbserver/server.c @@ -30,7 +30,19 @@ #include #endif +/* The thread set with an `Hc' packet. `Hc' is deprecated in favor of + `vCont'. Note the multi-process extensions made `vCont' a + requirement, so `Hc pPID.TID' is pretty much undefined. So + CONT_THREAD can be null_ptid for no `Hc' thread, minus_one_ptid for + resuming all threads of the process (again, `Hc' isn't used for + multi-process), or a specific thread ptid_t. + + We also set this when handling a single-thread `vCont' resume, as + some places in the backends check it to know when (and for which + thread) single-thread scheduler-locking is in effect. */ ptid_t cont_thread; + +/* The thread set with an `Hg' packet. */ ptid_t general_thread; int server_waiting; @@ -262,6 +274,10 @@ start_inferior (char **argv) signal (SIGTTIN, SIG_DFL); #endif + /* Clear this so the backend doesn't get confused, thinking + CONT_THREAD died, and it needs to resume all threads. */ + cont_thread = null_ptid; + signal_pid = create_inferior (new_argv[0], new_argv); /* FIXME: we don't actually know at this point that the create @@ -1962,9 +1978,13 @@ handle_v_cont (char *own_buf) if (i < n) resume_info[i] = default_action; - /* Still used in occasional places in the backend. */ + /* `cont_thread' is still used in occasional places in the backend, + to implement single-thread scheduler-locking. Doesn't make sense + to set it if we see a stop request, or any form of wildcard + vCont. */ if (n == 1 - && !ptid_equal (resume_info[0].thread, minus_one_ptid) + && !(ptid_equal (resume_info[0].thread, minus_one_ptid) + || ptid_get_lwp (resume_info[0].thread) == -1) && resume_info[0].kind != resume_stop) cont_thread = resume_info[0].thread; else -- 2.7.4