Mirror of the gdb-patches mailing list
 help / color / mirror / Atom feed
From: "Philippe Waroquiers" <philippe.waroquiers@skynet.be>
To: "Eli Zaretskii" <eliz@gnu.org>
Cc: <gdb-patches@sourceware.org>
Subject: Re: PATCH : allow to set length of hw watchpoints (e.g. for Valgrind gdbserver)
Date: Sun, 15 May 2011 20:12:00 -0000	[thread overview]
Message-ID: <6CA956FB8BFB4CAB823CD8593BA606B0@soleil> (raw)
In-Reply-To: <83vcxbeu07.fsf@gnu.org>

[-- Attachment #1: Type: text/plain, Size: 5625 bytes --]

Thanks for the quick review.
Find below a new version of the patch (also in attachment).

> If this is accepted, I think this is NEWS worthy.
Added a paragraph to describe this. 

> I think we should tell explicitly that the limit is in bytes.  (Btw,
> why the corresponding data types are `int' and not `ssize_t'?)
Added 'in bytes' in the doc and in the on-line command description.
Note that I have kept 'int' as all other similar variables are int, and an int
will be large enough for any reasonable watchpoint.

> Also, I think we also document the "show" counterpart of each "set"
> command.
Done.

2011-05-14  Philippe Waroquiers <philippe.waroquiers@skynet.be>
 * remote.c (remote_region_ok_for_hw_watchpoint): New function.
 (remote_hw_watchpoint_length_limit): New variable.
 (_initialize_remote) add set,show cmds for this new variable.
 gdb.texinfo: document these new commands.
 NEWS: document the change.

Index: gdb/NEWS
===================================================================
RCS file: /cvs/src/src/gdb/NEWS,v
retrieving revision 1.441
diff -c -p -r1.441 NEWS
*** gdb/NEWS 13 May 2011 22:36:06 -0000 1.441
--- gdb/NEWS 15 May 2011 19:51:54 -0000
***************
*** 3,8 ****
--- 3,18 ----
  
  *** Changes since GDB 7.3
  
+ * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
+   and "show remote hardware-watchpoint-length-limit". These allows to
+   set or show the maximum length limit (in bytes) of a remote
+   target hardware watchpoint.
+ 
+   This allows e.g. to use "unlimited" hardware watchpoints with the
+   gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
+   watchpoints are slower than real hardware watchpoints but are
+   significantly faster than gdb software watchpoints.
+ 
  * libthread-db-search-path now supports two special values: $sdir and $pdir.
    $sdir specifies the default system locations of shared libraries.
    $pdir specifies the directory where the libpthread used by the application
Index: gdb/remote.c
===================================================================
RCS file: /cvs/src/src/gdb/remote.c,v
retrieving revision 1.446
diff -c -p -r1.446 remote.c
*** gdb/remote.c 12 May 2011 12:09:16 -0000 1.446
--- gdb/remote.c 15 May 2011 19:52:00 -0000
*************** remote_remove_watchpoint (CORE_ADDR addr
*** 7756,7764 ****
--- 7756,7778 ----
  
  
  int remote_hw_watchpoint_limit = -1;
+ int remote_hw_watchpoint_length_limit = -1;
  int remote_hw_breakpoint_limit = -1;
  
  static int
+ remote_region_ok_for_hw_watchpoint (CORE_ADDR addr, int len)
+ {
+   if (remote_hw_watchpoint_length_limit == 0)
+     return 0;
+   else if (remote_hw_watchpoint_length_limit < 0)
+     return 1;
+   else if (len <= remote_hw_watchpoint_length_limit)
+     return 1;
+   else
+     return 0;
+ }
+ 
+ static int
  remote_check_watch_resources (int type, int cnt, int ot)
  {
    if (type == bp_hardware_breakpoint)
*************** Specify the serial device it is connecte
*** 10326,10331 ****
--- 10340,10347 ----
    remote_ops.to_can_use_hw_breakpoint = remote_check_watch_resources;
    remote_ops.to_insert_hw_breakpoint = remote_insert_hw_breakpoint;
    remote_ops.to_remove_hw_breakpoint = remote_remove_hw_breakpoint;
+   remote_ops.to_region_ok_for_hw_watchpoint
+      = remote_region_ok_for_hw_watchpoint;
    remote_ops.to_insert_watchpoint = remote_insert_watchpoint;
    remote_ops.to_remove_watchpoint = remote_remove_watchpoint;
    remote_ops.to_kill = remote_kill;
*************** Specify a negative limit for unlimited."
*** 10735,10740 ****
--- 10751,10765 ----
          number of target hardware
          watchpoints is %s.  */
         &remote_set_cmdlist, &remote_show_cmdlist);
+   add_setshow_zinteger_cmd ("hardware-watchpoint-length-limit", no_class,
+        &remote_hw_watchpoint_length_limit, _("\
+ Set the maximum length (in bytes) of a target hardware watchpoint."), _("\
+ Show the maximum length (in bytes) of a target hardware watchpoint."), _("\
+ Specify a negative limit for unlimited."),
+        NULL, NULL, /* FIXME: i18n: The maximum
+                                            length (in bytes) of a target
+                                            hardware watchpoint is %s.  */
+        &remote_set_cmdlist, &remote_show_cmdlist);
    add_setshow_zinteger_cmd ("hardware-breakpoint-limit", no_class,
         &remote_hw_breakpoint_limit, _("\
  Set the maximum number of target hardware breakpoints."), _("\
Index: gdb/doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.838
diff -c -p -r1.838 gdb.texinfo
*** gdb/doc/gdb.texinfo 13 May 2011 22:36:07 -0000 1.838
--- gdb/doc/gdb.texinfo 15 May 2011 19:52:25 -0000
*************** responses.
*** 16578,16583 ****
--- 16578,16595 ----
  Restrict @value{GDBN} to using @var{limit} remote hardware breakpoint or
  watchpoints.  A limit of -1, the default, is treated as unlimited.
  
+ @cindex limit hardware watchpoints length
+ @cindex remote target, limit watchpoints length
+ @anchor{set remote hardware-watchpoint-length-limit}
+ @item set remote hardware-watchpoint-length-limit @var{limit}
+ Restrict @value{GDBN} to using @var{limit} bytes for the maximum length of
+ a remote hardware watchpoint.  A limit of -1, the default, is treated
+ as unlimited.
+ 
+ @item show remote hardware-watchpoint-length-limit
+ Show the current limit (in bytes) of the maximum length of
+ a remote hardware watchpoint.
+ 
  @item set remote exec-file @var{filename}
  @itemx show remote exec-file
  @anchor{set remote exec-file}

[-- Attachment #2: set-length-limit-3.desc.txt --]
[-- Type: text/plain, Size: 5144 bytes --]

2011-05-14  Philippe Waroquiers <philippe.waroquiers@skynet.be>
	* remote.c (remote_region_ok_for_hw_watchpoint): New function.
	(remote_hw_watchpoint_length_limit): New variable.
	(_initialize_remote) add set,show cmds for this new variable.
	gdb.texinfo: document these new commands.
	NEWS: document the change.

Index: gdb/NEWS
===================================================================
RCS file: /cvs/src/src/gdb/NEWS,v
retrieving revision 1.441
diff -c -p -r1.441 NEWS
*** gdb/NEWS	13 May 2011 22:36:06 -0000	1.441
--- gdb/NEWS	15 May 2011 19:51:54 -0000
***************
*** 3,8 ****
--- 3,18 ----
  
  *** Changes since GDB 7.3
  
+ * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
+   and "show remote hardware-watchpoint-length-limit". These allows to
+   set or show the maximum length limit (in bytes) of a remote
+   target hardware watchpoint.
+ 
+   This allows e.g. to use "unlimited" hardware watchpoints with the
+   gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
+   watchpoints are slower than real hardware watchpoints but are
+   significantly faster than gdb software watchpoints.
+ 
  * libthread-db-search-path now supports two special values: $sdir and $pdir.
    $sdir specifies the default system locations of shared libraries.
    $pdir specifies the directory where the libpthread used by the application
Index: gdb/remote.c
===================================================================
RCS file: /cvs/src/src/gdb/remote.c,v
retrieving revision 1.446
diff -c -p -r1.446 remote.c
*** gdb/remote.c	12 May 2011 12:09:16 -0000	1.446
--- gdb/remote.c	15 May 2011 19:52:00 -0000
*************** remote_remove_watchpoint (CORE_ADDR addr
*** 7756,7764 ****
--- 7756,7778 ----
  
  
  int remote_hw_watchpoint_limit = -1;
+ int remote_hw_watchpoint_length_limit = -1;
  int remote_hw_breakpoint_limit = -1;
  
  static int
+ remote_region_ok_for_hw_watchpoint (CORE_ADDR addr, int len)
+ {
+   if (remote_hw_watchpoint_length_limit == 0)
+     return 0;
+   else if (remote_hw_watchpoint_length_limit < 0)
+     return 1;
+   else if (len <= remote_hw_watchpoint_length_limit)
+     return 1;
+   else
+     return 0;
+ }
+ 
+ static int
  remote_check_watch_resources (int type, int cnt, int ot)
  {
    if (type == bp_hardware_breakpoint)
*************** Specify the serial device it is connecte
*** 10326,10331 ****
--- 10340,10347 ----
    remote_ops.to_can_use_hw_breakpoint = remote_check_watch_resources;
    remote_ops.to_insert_hw_breakpoint = remote_insert_hw_breakpoint;
    remote_ops.to_remove_hw_breakpoint = remote_remove_hw_breakpoint;
+   remote_ops.to_region_ok_for_hw_watchpoint
+      = remote_region_ok_for_hw_watchpoint;
    remote_ops.to_insert_watchpoint = remote_insert_watchpoint;
    remote_ops.to_remove_watchpoint = remote_remove_watchpoint;
    remote_ops.to_kill = remote_kill;
*************** Specify a negative limit for unlimited."
*** 10735,10740 ****
--- 10751,10765 ----
  					   number of target hardware
  					   watchpoints is %s.  */
  			    &remote_set_cmdlist, &remote_show_cmdlist);
+   add_setshow_zinteger_cmd ("hardware-watchpoint-length-limit", no_class,
+ 			    &remote_hw_watchpoint_length_limit, _("\
+ Set the maximum length (in bytes) of a target hardware watchpoint."), _("\
+ Show the maximum length (in bytes) of a target hardware watchpoint."), _("\
+ Specify a negative limit for unlimited."),
+ 			    NULL, NULL, /* FIXME: i18n: The maximum
+                                            length (in bytes) of a target
+                                            hardware watchpoint is %s.  */
+ 			    &remote_set_cmdlist, &remote_show_cmdlist);
    add_setshow_zinteger_cmd ("hardware-breakpoint-limit", no_class,
  			    &remote_hw_breakpoint_limit, _("\
  Set the maximum number of target hardware breakpoints."), _("\
Index: gdb/doc/gdb.texinfo
===================================================================
RCS file: /cvs/src/src/gdb/doc/gdb.texinfo,v
retrieving revision 1.838
diff -c -p -r1.838 gdb.texinfo
*** gdb/doc/gdb.texinfo	13 May 2011 22:36:07 -0000	1.838
--- gdb/doc/gdb.texinfo	15 May 2011 19:52:25 -0000
*************** responses.
*** 16578,16583 ****
--- 16578,16595 ----
  Restrict @value{GDBN} to using @var{limit} remote hardware breakpoint or
  watchpoints.  A limit of -1, the default, is treated as unlimited.
  
+ @cindex limit hardware watchpoints length
+ @cindex remote target, limit watchpoints length
+ @anchor{set remote hardware-watchpoint-length-limit}
+ @item set remote hardware-watchpoint-length-limit @var{limit}
+ Restrict @value{GDBN} to using @var{limit} bytes for the maximum length of
+ a remote hardware watchpoint.  A limit of -1, the default, is treated
+ as unlimited.
+ 
+ @item show remote hardware-watchpoint-length-limit
+ Show the current limit (in bytes) of the maximum length of
+ a remote hardware watchpoint.
+ 
  @item set remote exec-file @var{filename}
  @itemx show remote exec-file
  @anchor{set remote exec-file}

  reply	other threads:[~2011-05-15 20:12 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-15 17:39 Philippe Waroquiers
2011-05-15 17:47 ` Eli Zaretskii
2011-05-15 20:12   ` Philippe Waroquiers [this message]
2011-05-15 20:30     ` Eli Zaretskii
2011-05-15 20:43       ` Philippe Waroquiers

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6CA956FB8BFB4CAB823CD8593BA606B0@soleil \
    --to=philippe.waroquiers@skynet.be \
    --cc=eliz@gnu.org \
    --cc=gdb-patches@sourceware.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox