From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 15551 invoked by alias); 30 Aug 2002 23:34:43 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 15521 invoked from network); 30 Aug 2002 23:34:42 -0000 Received: from unknown (HELO cygnus.com) (205.180.83.203) by sources.redhat.com with SMTP; 30 Aug 2002 23:34:42 -0000 Received: from redhat.com (reddwarf.sfbay.redhat.com [172.16.24.50]) by runyon.cygnus.com (8.8.7-cygnus/8.8.7) with ESMTP id QAA18099; Fri, 30 Aug 2002 16:26:47 -0700 (PDT) Message-ID: <3D70010F.EAE68958@redhat.com> Date: Fri, 30 Aug 2002 16:41:00 -0000 From: Michael Snyder Organization: Red Hat, Inc. X-Accept-Language: en MIME-Version: 1.0 To: Daniel Jacobowitz CC: gdb-patches@sources.redhat.com, "Van Assche, Bart" Subject: Re: gdbserver References: <6703765BD7FDD411AB0900508BFCACD3017D106E@bnbeluimex01.barconet.com> <20020830222342.GA32278@nevyn.them.org> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-SW-Source: 2002-08/txt/msg01058.txt.bz2 Daniel Jacobowitz wrote: > > [Bart, please try this patch.] > > List folks, > > I think the time has come for generic_prepare_to_proceed to actually be > used. The problem addressed by this patch is that PREPARE_TO_PROCEED > is not a native-only macro (and not part of the target stack). So > lin_lwp_prepare_to_proceed would be called when using gdbserver, and of > course trap_ptid would be null_ptid or stale. > generic_prepare_to_proceed works correctly for lin-lwp native > debugging, and for remote debugging. This patch fixes an incorrect > breakpoint hit after manually switching threads; i.e. the same > breakpoint would be hit a second time. I'll try to write an > independent test case. > > Patch look OK? Of course, a simpler and less intrusive fix would be to simply define PREPARE_TO_PROCEED as generic_prepare_to_proceed, and remove lin_lwp_prepare_to_proceed. I'm not necessarily objecting to this patch -- just pointing out an alternative. If people think we're ready for this step, it's fine with me. > On Fri, Aug 23, 2002 at 08:35:17AM +0200, Van Assche, Bart wrote: > > Hello Dan, > > > > Thanks for your response. I tried with the latest snapshot, and debugging > > threads has indeed improved. However, I still get a SIGSEGV reported when I > > use remote debugging (that I do not get with native debugging -- see also > > below). > > -- > Daniel Jacobowitz > MontaVista Software Debian GNU/Linux Developer > > 2002-08-30 Daniel Jacobowitz > > * arch-utils.c (default_prepare_to_proceed): Remove. > * arch-utils.h (default_prepare_to_proceed): Remove prototype. > * gdbarch.sh (PREPARE_TO_PROCEED): Change default to > generic_prepare_to_proceed. > * gdbarch.c: Regenerated. > * gdbarch.h: Regenerated. > * lin-lwp.c (lin_lwp_prepare_to_proceed): Remove. > * config/nm-linux.h (PREPARE_TO_PROCEED): Don't define. > (lin_lwp_prepare_to_proceed): Remove prototype. > > Index: arch-utils.c > =================================================================== > RCS file: /cvs/src/src/gdb/arch-utils.c,v > retrieving revision 1.67 > diff -u -p -r1.67 arch-utils.c > --- arch-utils.c 24 Aug 2002 00:21:34 -0000 1.67 > +++ arch-utils.c 30 Aug 2002 22:13:11 -0000 > @@ -320,13 +320,6 @@ default_frame_address (struct frame_info > return fi->frame; > } > > -/* Default prepare_to_procced(). */ > -int > -default_prepare_to_proceed (int select_it) > -{ > - return 0; > -} > - > /* Generic prepare_to_proceed(). This one should be suitable for most > targets that support threads. */ > int > Index: gdbarch.c > =================================================================== > RCS file: /cvs/src/src/gdb/gdbarch.c,v > retrieving revision 1.146 > diff -u -p -r1.146 gdbarch.c > --- gdbarch.c 24 Aug 2002 00:21:34 -0000 1.146 > +++ gdbarch.c 30 Aug 2002 22:13:12 -0000 > @@ -530,7 +530,7 @@ gdbarch_alloc (const struct gdbarch_info > current_gdbarch->memory_insert_breakpoint = default_memory_insert_breakpoint; > current_gdbarch->memory_remove_breakpoint = default_memory_remove_breakpoint; > current_gdbarch->decr_pc_after_break = -1; > - current_gdbarch->prepare_to_proceed = default_prepare_to_proceed; > + current_gdbarch->prepare_to_proceed = generic_prepare_to_proceed; > current_gdbarch->function_start_offset = -1; > current_gdbarch->remote_translate_xfer_address = generic_remote_translate_xfer_address; > current_gdbarch->frame_args_skip = -1; > Index: gdbarch.h > =================================================================== > RCS file: /cvs/src/src/gdb/gdbarch.h,v > retrieving revision 1.114 > diff -u -p -r1.114 gdbarch.h > --- gdbarch.h 24 Aug 2002 00:21:34 -0000 1.114 > +++ gdbarch.h 30 Aug 2002 22:13:13 -0000 > @@ -1809,7 +1809,7 @@ extern void set_gdbarch_decr_pc_after_br > > /* Default (function) for non- multi-arch platforms. */ > #if (!GDB_MULTI_ARCH) && !defined (PREPARE_TO_PROCEED) > -#define PREPARE_TO_PROCEED(select_it) (default_prepare_to_proceed (select_it)) > +#define PREPARE_TO_PROCEED(select_it) (generic_prepare_to_proceed (select_it)) > #endif > > typedef int (gdbarch_prepare_to_proceed_ftype) (int select_it); > Index: gdbarch.sh > =================================================================== > RCS file: /cvs/src/src/gdb/gdbarch.sh,v > retrieving revision 1.158 > diff -u -p -r1.158 gdbarch.sh > --- gdbarch.sh 24 Aug 2002 00:21:34 -0000 1.158 > +++ gdbarch.sh 30 Aug 2002 22:13:14 -0000 > @@ -549,7 +549,7 @@ f:2:BREAKPOINT_FROM_PC:const unsigned ch > f:2:MEMORY_INSERT_BREAKPOINT:int:memory_insert_breakpoint:CORE_ADDR addr, char *contents_cache:addr, contents_cache::0:default_memory_insert_breakpoint::0 > f:2:MEMORY_REMOVE_BREAKPOINT:int:memory_remove_breakpoint:CORE_ADDR addr, char *contents_cache:addr, contents_cache::0:default_memory_remove_breakpoint::0 > v:2:DECR_PC_AFTER_BREAK:CORE_ADDR:decr_pc_after_break::::0:-1 > -f::PREPARE_TO_PROCEED:int:prepare_to_proceed:int select_it:select_it::0:default_prepare_to_proceed::0 > +f::PREPARE_TO_PROCEED:int:prepare_to_proceed:int select_it:select_it::0:generic_prepare_to_proceed::0 > v:2:FUNCTION_START_OFFSET:CORE_ADDR:function_start_offset::::0:-1 > # > f:2:REMOTE_TRANSLATE_XFER_ADDRESS:void:remote_translate_xfer_address:CORE_ADDR gdb_addr, int gdb_len, CORE_ADDR *rem_addr, int *rem_len:gdb_addr, gdb_len, rem_addr, rem_len:::generic_remote_translate_xfer_address::0 > Index: lin-lwp.c > =================================================================== > RCS file: /cvs/src/src/gdb/lin-lwp.c,v > retrieving revision 1.35 > diff -u -p -r1.35 lin-lwp.c > --- lin-lwp.c 27 Aug 2002 22:37:06 -0000 1.35 > +++ lin-lwp.c 30 Aug 2002 22:13:14 -0000 > @@ -294,46 +294,6 @@ iterate_over_lwps (int (*callback) (stru > } > > > -/* Implementation of the PREPARE_TO_PROCEED hook for the GNU/Linux LWP > - layer. > - > - Note that this implementation is potentially redundant now that > - default_prepare_to_proceed() has been added. > - > - FIXME This may not support switching threads after Ctrl-C > - correctly. The default implementation does support this. */ > - > -int > -lin_lwp_prepare_to_proceed (void) > -{ > - if (! ptid_equal (trap_ptid, null_ptid) > - && ! ptid_equal (inferior_ptid, trap_ptid)) > - { > - /* Switched over from TRAP_PID. */ > - CORE_ADDR stop_pc = read_pc (); > - CORE_ADDR trap_pc; > - > - /* Avoid switching where it wouldn't do any good, i.e. if both > - threads are at the same breakpoint. */ > - trap_pc = read_pc_pid (trap_ptid); > - if (trap_pc != stop_pc && breakpoint_here_p (trap_pc)) > - { > - /* User hasn't deleted the breakpoint. Return non-zero, and > - switch back to TRAP_PID. */ > - inferior_ptid = trap_ptid; > - > - /* FIXME: Is this stuff really necessary? */ > - flush_cached_frames (); > - registers_changed (); > - > - return 1; > - } > - } > - > - return 0; > -} > - > - > #if 0 > static void > lin_lwp_open (char *args, int from_tty) > Index: config/nm-linux.h > =================================================================== > RCS file: /cvs/src/src/gdb/config/nm-linux.h,v > retrieving revision 1.12 > diff -u -p -r1.12 nm-linux.h > --- config/nm-linux.h 24 Feb 2002 22:56:04 -0000 1.12 > +++ config/nm-linux.h 30 Aug 2002 22:13:14 -0000 > @@ -49,9 +49,6 @@ struct target_waitstatus; > extern ptid_t child_wait (ptid_t ptid, struct target_waitstatus *ourstatus); > #define CHILD_WAIT > > -extern int lin_lwp_prepare_to_proceed (void); > -#define PREPARE_TO_PROCEED(select_it) lin_lwp_prepare_to_proceed () > - > extern void lin_lwp_attach_lwp (ptid_t ptid, int verbose); > #define ATTACH_LWP(ptid, verbose) lin_lwp_attach_lwp ((ptid), (verbose)) > > Index: arch-utils.h > =================================================================== > RCS file: /cvs/src/src/gdb/arch-utils.h,v > retrieving revision 1.41 > diff -u -p -r1.41 arch-utils.h > --- arch-utils.h 24 Aug 2002 00:21:34 -0000 1.41 > +++ arch-utils.h 30 Aug 2002 22:15:25 -0000 > @@ -115,8 +115,6 @@ extern CORE_ADDR default_frame_address ( > > /* Default prepare_to_procced. */ > > -extern int default_prepare_to_proceed (int select_it); > - > extern int generic_prepare_to_proceed (int select_it); > > /* Versions of init_frame_pc(). Do nothing; do the default. */