From: Yao Qi <yao@codesourcery.com>
To: <gdb-patches@sourceware.org>
Subject: [PATCH 2/3] Trust readonly sections if target has memory protection
Date: Fri, 06 Sep 2013 02:03:00 -0000 [thread overview]
Message-ID: <1378432920-7731-3-git-send-email-yao@codesourcery.com> (raw)
In-Reply-To: <1378432920-7731-1-git-send-email-yao@codesourcery.com>
This patch first changes command "trust-readonly-sections" to an
auto_boolean command, so "auto" means that GDB trusts read-only
sections if the target has memory protection. Then, this patch adds a
gdbarch hook method "has_memory_protection". Patch 2/2 is to
implement the hook method for linux target.
gdb:
2013-09-06 Yao Qi <yao@codesourcery.com>
* arch-utils.c (default_has_memory_protection): New function.
* arch-utils.h (default_has_memory_protection): Declaration.
* gdbarch.sh (has_memory_protection): New hook method.
* gdbarch.c: Re-generated.
* gdbarch.h: Re-generated.
* target.c (trust_readonly): Change type to 'enum auto_boolean'
and initialize it to 'AUTO_BOOLEAN_AUTO'.
(trust_readonly_p): New function.
(memory_xfer_partial_1): Call trust_readonly_p.
(initialize_targets): Register command
"trust-readonly-sections" as add_setshow_auto_boolean_cmd.
* NEWS: Describe the default option of
"trust-readonly-sections" becomes "auto" and the related
changes.
gdb/doc:
2013-09-06 Yao Qi <yao@codesourcery.com>
* gdb.texinfo (Files): Explain the default option of
"trust-readonly-sections" is "auto".
---
gdb/NEWS | 4 ++++
gdb/arch-utils.c | 7 +++++++
gdb/arch-utils.h | 2 ++
gdb/doc/gdb.texinfo | 6 +++++-
gdb/gdbarch.c | 24 ++++++++++++++++++++++++
gdb/gdbarch.h | 6 ++++++
gdb/gdbarch.sh | 3 +++
gdb/target.c | 32 +++++++++++++++++++++++---------
8 files changed, 74 insertions(+), 10 deletions(-)
diff --git a/gdb/NEWS b/gdb/NEWS
index ad97f6f..a3bdf84 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,10 @@
*** Changes since GDB 7.6
+* The default value of option "trust-readonly-sections" is "auto". GDB
+ trusts the contents of read-only sections from the object file on the
+ GNU/Linux targets.
+
* The "maintenance print objfiles" command now takes an optional regexp.
* The "catch syscall" command now works on arm*-linux* targets.
diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c
index 459fd88..8418bbc 100644
--- a/gdb/arch-utils.c
+++ b/gdb/arch-utils.c
@@ -769,6 +769,13 @@ default_has_shared_address_space (struct gdbarch *gdbarch)
}
int
+default_has_memory_protection (struct gdbarch *gdbarch)
+{
+ /* Simply say no. */
+ return 0;
+}
+
+int
default_fast_tracepoint_valid_at (struct gdbarch *gdbarch,
CORE_ADDR addr, int *isize, char **msg)
{
diff --git a/gdb/arch-utils.h b/gdb/arch-utils.h
index 3f0e64f..61973c0 100644
--- a/gdb/arch-utils.h
+++ b/gdb/arch-utils.h
@@ -153,6 +153,8 @@ extern struct gdbarch *get_current_arch (void);
extern int default_has_shared_address_space (struct gdbarch *);
+extern int default_has_memory_protection (struct gdbarch *gdbarch);
+
extern int default_fast_tracepoint_valid_at (struct gdbarch *gdbarch,
CORE_ADDR addr,
int *isize, char **msg);
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index d8e4adf..5efa966 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -16673,7 +16673,11 @@ out of the object file, rather than from the target program.
For some targets (notably embedded ones), this can be a significant
enhancement to debugging performance.
-The default is off.
+@item set trust-readonly-sections auto
+This is the default mode. Tell @value{GDBN} to trust read-only
+sections on some targets which have memory protection, such as
+GNU/Linux, because the contents of the section in the target program
+can't change.
@item set trust-readonly-sections off
Tell @value{GDBN} not to trust readonly sections. This means that
diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c
index 1f3380e..13e5e82 100644
--- a/gdb/gdbarch.c
+++ b/gdb/gdbarch.c
@@ -278,6 +278,7 @@ struct gdbarch
int has_global_solist;
int has_global_breakpoints;
gdbarch_has_shared_address_space_ftype *has_shared_address_space;
+ gdbarch_has_memory_protection_ftype *has_memory_protection;
gdbarch_fast_tracepoint_valid_at_ftype *fast_tracepoint_valid_at;
gdbarch_auto_charset_ftype *auto_charset;
gdbarch_auto_wide_charset_ftype *auto_wide_charset;
@@ -451,6 +452,7 @@ struct gdbarch startup_gdbarch =
0, /* has_global_solist */
0, /* has_global_breakpoints */
default_has_shared_address_space, /* has_shared_address_space */
+ default_has_memory_protection, /* has_memory_protection */
default_fast_tracepoint_valid_at, /* fast_tracepoint_valid_at */
default_auto_charset, /* auto_charset */
default_auto_wide_charset, /* auto_wide_charset */
@@ -546,6 +548,7 @@ gdbarch_alloc (const struct gdbarch_info *info,
gdbarch->displaced_step_location = NULL;
gdbarch->relocate_instruction = NULL;
gdbarch->has_shared_address_space = default_has_shared_address_space;
+ gdbarch->has_memory_protection = default_has_memory_protection;
gdbarch->fast_tracepoint_valid_at = default_fast_tracepoint_valid_at;
gdbarch->auto_charset = default_auto_charset;
gdbarch->auto_wide_charset = default_auto_wide_charset;
@@ -757,6 +760,7 @@ verify_gdbarch (struct gdbarch *gdbarch)
/* Skip verify of has_global_solist, invalid_p == 0 */
/* Skip verify of has_global_breakpoints, invalid_p == 0 */
/* Skip verify of has_shared_address_space, invalid_p == 0 */
+ /* Skip verify of has_memory_protection, invalid_p == 0 */
/* Skip verify of fast_tracepoint_valid_at, invalid_p == 0 */
/* Skip verify of auto_charset, invalid_p == 0 */
/* Skip verify of auto_wide_charset, invalid_p == 0 */
@@ -1078,6 +1082,9 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file)
"gdbarch_dump: has_global_solist = %s\n",
plongest (gdbarch->has_global_solist));
fprintf_unfiltered (file,
+ "gdbarch_dump: has_memory_protection = <%s>\n",
+ host_address_to_string (gdbarch->has_memory_protection));
+ fprintf_unfiltered (file,
"gdbarch_dump: has_shared_address_space = <%s>\n",
host_address_to_string (gdbarch->has_shared_address_space));
fprintf_unfiltered (file,
@@ -4240,6 +4247,23 @@ set_gdbarch_has_shared_address_space (struct gdbarch *gdbarch,
}
int
+gdbarch_has_memory_protection (struct gdbarch *gdbarch)
+{
+ gdb_assert (gdbarch != NULL);
+ gdb_assert (gdbarch->has_memory_protection != NULL);
+ if (gdbarch_debug >= 2)
+ fprintf_unfiltered (gdb_stdlog, "gdbarch_has_memory_protection called\n");
+ return gdbarch->has_memory_protection (gdbarch);
+}
+
+void
+set_gdbarch_has_memory_protection (struct gdbarch *gdbarch,
+ gdbarch_has_memory_protection_ftype has_memory_protection)
+{
+ gdbarch->has_memory_protection = has_memory_protection;
+}
+
+int
gdbarch_fast_tracepoint_valid_at (struct gdbarch *gdbarch, CORE_ADDR addr, int *isize, char **msg)
{
gdb_assert (gdbarch != NULL);
diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h
index 013f071..ade07d7 100644
--- a/gdb/gdbarch.h
+++ b/gdb/gdbarch.h
@@ -1176,6 +1176,12 @@ typedef int (gdbarch_has_shared_address_space_ftype) (struct gdbarch *gdbarch);
extern int gdbarch_has_shared_address_space (struct gdbarch *gdbarch);
extern void set_gdbarch_has_shared_address_space (struct gdbarch *gdbarch, gdbarch_has_shared_address_space_ftype *has_shared_address_space);
+/* True if the target has memory protection. */
+
+typedef int (gdbarch_has_memory_protection_ftype) (struct gdbarch *gdbarch);
+extern int gdbarch_has_memory_protection (struct gdbarch *gdbarch);
+extern void set_gdbarch_has_memory_protection (struct gdbarch *gdbarch, gdbarch_has_memory_protection_ftype *has_memory_protection);
+
/* True if a fast tracepoint can be set at an address. */
typedef int (gdbarch_fast_tracepoint_valid_at_ftype) (struct gdbarch *gdbarch, CORE_ADDR addr, int *isize, char **msg);
diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh
index 04ca38c..080a5ec 100755
--- a/gdb/gdbarch.sh
+++ b/gdb/gdbarch.sh
@@ -932,6 +932,9 @@ v:int:has_global_breakpoints:::0:0::0
# True if inferiors share an address space (e.g., uClinux).
m:int:has_shared_address_space:void:::default_has_shared_address_space::0
+# True if the target has memory protection.
+m:int:has_memory_protection:void:::default_has_memory_protection::0
+
# True if a fast tracepoint can be set at an address.
m:int:fast_tracepoint_valid_at:CORE_ADDR addr, int *isize, char **msg:addr, isize, msg::default_fast_tracepoint_valid_at::0
diff --git a/gdb/target.c b/gdb/target.c
index d55712d..80f1f87 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -168,10 +168,10 @@ struct target_ops current_target;
static struct cmd_list_element *targetlist = NULL;
-/* Nonzero if we should trust readonly sections from the
+/* If AUTO_BOOLEAN_TRUE, we should trust readonly sections from the
executable when reading memory. */
-static int trust_readonly = 0;
+static enum auto_boolean trust_readonly = AUTO_BOOLEAN_AUTO;
/* Nonzero if we should show true memory content including
memory breakpoint inserted by gdb. */
@@ -1437,6 +1437,18 @@ memory_xfer_live_readonly_partial (struct target_ops *ops,
return 0;
}
+/* Return true if GDB trusts readonly sections. Return false
+ otherwise. */
+
+static int
+trust_readonly_p (void)
+{
+ if (trust_readonly != AUTO_BOOLEAN_AUTO)
+ return trust_readonly == AUTO_BOOLEAN_TRUE;
+
+ return gdbarch_has_memory_protection (target_gdbarch ());
+}
+
/* Perform a partial memory transfer.
For docs see target.h, to_xfer_partial. */
@@ -1472,7 +1484,7 @@ memory_xfer_partial_1 (struct target_ops *ops, enum target_object object,
}
/* Try the executable files, if "trust-readonly-sections" is set. */
- if (readbuf != NULL && trust_readonly)
+ if (readbuf != NULL && trust_readonly_p ())
{
struct target_section *secp;
struct target_section_table *table;
@@ -5086,16 +5098,18 @@ command."),
show_targetdebug,
&setdebuglist, &showdebuglist);
- add_setshow_boolean_cmd ("trust-readonly-sections", class_support,
- &trust_readonly, _("\
+ add_setshow_auto_boolean_cmd ("trust-readonly-sections", class_support,
+ &trust_readonly, _("\
Set mode for reading from readonly sections."), _("\
Show mode for reading from readonly sections."), _("\
When this mode is on, memory reads from readonly sections (such as .text)\n\
will be read from the object file instead of from the target. This will\n\
-result in significant performance improvement for remote targets."),
- NULL,
- show_trust_readonly,
- &setlist, &showlist);
+result in significant performance improvement for remote targets.\n\
+When this mode is auto, memory reads from readonly sections will be\n\
+read from the object file if the target has memory protection.\n"),
+ NULL,
+ show_trust_readonly,
+ &setlist, &showlist);
add_com ("monitor", class_obscure, do_monitor_command,
_("Send a command to the remote monitor (remote targets only)."));
--
1.7.7.6
next prev parent reply other threads:[~2013-09-06 2:03 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-06 2:03 [PATCH 0/3] " Yao Qi
2013-09-06 2:03 ` Yao Qi [this message]
2013-09-06 6:05 ` [PATCH 2/3] " Eli Zaretskii
2013-09-06 9:07 ` Yao Qi
2013-09-06 9:24 ` Eli Zaretskii
2013-09-06 2:03 ` [PATCH 1/3] set trust-readonly-sections off in test cases Yao Qi
2013-09-06 5:56 ` Eli Zaretskii
2013-09-06 17:23 ` Pedro Alves
2013-09-06 2:03 ` [PATCH 3/3] Linux has memory protection Yao Qi
2013-09-06 5:57 ` [PATCH 0/3] Trust readonly sections if target " Eli Zaretskii
2013-09-06 8:24 ` Yao Qi
2013-09-06 8:45 ` Eli Zaretskii
2013-09-06 13:03 ` Joel Brobecker
2013-09-06 13:27 ` Yao Qi
2013-09-06 13:32 ` Eli Zaretskii
2013-09-06 14:17 ` Pierre Muller
[not found] ` <"000d01ceab0b$d53ae600$7fb0b200$@muller"@ics-cnrs.unistra.fr>
2013-09-06 14:38 ` Eli Zaretskii
2013-09-06 14:52 ` Joel Brobecker
2013-09-06 15:56 ` Eli Zaretskii
2013-09-06 18:10 ` Joel Brobecker
2013-09-06 18:36 ` Eli Zaretskii
2013-09-06 13:00 ` Joel Brobecker
2013-09-08 12:04 ` [PATCH 0/7 V2] " Yao Qi
2013-09-08 12:04 ` [PATCH 1/7] Emit a warning when writing to a readonly section and trust_readonly is true Yao Qi
2013-09-08 15:10 ` Eli Zaretskii
2013-09-08 12:05 ` [PATCH 5/7] DOC and NEWS Yao Qi
2013-09-08 12:05 ` [PATCH 6/7] Linux has memory protection Yao Qi
2013-09-08 12:05 ` [PATCH 3/7] New function windows_init_abi Yao Qi
2013-09-08 12:05 ` [PATCH 4/7] Trust readonly sections if target has memory protection Yao Qi
2013-09-08 15:13 ` Eli Zaretskii
2013-09-09 7:49 ` Yao Qi
2013-09-09 16:25 ` Eli Zaretskii
2013-09-08 12:05 ` [PATCH 7/7] Windows " Yao Qi
2013-09-08 12:05 ` [PATCH 2/7] set trust-readonly-sections off in test cases Yao Qi
2013-09-09 19:16 ` [PATCH 0/7 V2] Trust readonly sections if target has memory protection Mark Kettenis
2013-09-10 4:06 ` Yao Qi
2013-09-12 8:30 ` Yao Qi
2013-09-12 9:49 ` Mark Kettenis
2013-09-13 8:17 ` Yao Qi
2013-09-30 17:50 ` Pedro Alves
2013-09-30 18:08 ` Pedro Alves
2013-10-07 22:29 ` Stan Shebs
2013-10-08 12:18 ` Pedro Alves
2013-10-08 12:47 ` Abid, Hafiz
2013-10-08 13:36 ` tmirza
2013-10-09 2:24 ` Doug Evans
2013-10-23 10:16 ` Yao Qi
2013-10-15 0:44 ` Yao Qi
2013-09-20 2:47 ` [PATCH 0/7 V3] " Yao Qi
2013-09-20 2:47 ` [PATCH 7/7] Windows " Yao Qi
2013-09-20 2:47 ` [PATCH 1/7] Emit a query when writing to a readonly section and trust_readonly is true Yao Qi
2013-09-20 2:47 ` [PATCH 4/7] Trust readonly sections if target has memory protection and in remote debugging Yao Qi
2013-09-20 2:47 ` [PATCH 5/7] DOC and NEWS Yao Qi
2013-09-20 8:21 ` Eli Zaretskii
2013-09-20 2:47 ` [PATCH 2/7] set trust-readonly-sections off in test cases Yao Qi
2013-09-20 2:47 ` [PATCH 6/7] Linux has memory protection Yao Qi
2013-09-20 2:47 ` [PATCH 3/7] New function windows_init_abi Yao Qi
2013-09-30 18:23 ` Pedro Alves
2013-10-01 6:47 ` Yao Qi
2013-10-01 9:35 ` Pedro Alves
2013-10-01 13:23 ` Yao Qi
2013-09-29 13:51 ` [PATCH 0/7 V3] Trust readonly sections if target has memory protection Yao Qi
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