darkkirb/old-cross-binutils
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Move the traceframe_available_memory code from memory_xfer_partial_1 down to the targets

Browse source 
As a follow-up to

  [PATCH 7/8] Adjust read_value_memory to use to_xfer_partial
  https://sourceware.org/ml/gdb-patches/2014-02/msg00384.html

this patch moves traceframe_available_memory down to the target side.
After this patch, the gdb core code is cleaner, and code on handling
unavailable memory is moved to remote/tfile/ctf targets.

In details, this patch moves traceframe_available_memory code from
memory_xfer_partial_1 to remote target only, so remote target still
uses traceframe_info mechanism to check unavailable memory, and use
remote_ops to read them from read-only sections.  We don't use
traceframe_info mechanism for tfile and ctf target, because it is
fast to iterate all traceframes from trace file, so the summary
information got from traceframe_info is not necessary.

This patch also moves two functions to remote.c from target.c,
because they are only used in remote.c.  I'll clean them up in another
patch.

gdb:

2014-03-22  Yao Qi  <yao@codesourcery.com>

	* ctf.c (ctf_xfer_partial): Check the return value of
	exec_read_partial_read_only, if it is not TARGET_XFER_OK,
	return TARGET_XFER_UNAVAILABLE.
	* tracefile-tfile.c (tfile_xfer_partial): Likewise.
	* target.c (target_read_live_memory): Move it to remote.c.
	(memory_xfer_live_readonly_partial): Likewise.
	(memory_xfer_partial_1): Move some code to remote_read_bytes.
	* remote.c (target_read_live_memory): Moved from target.c.
	(memory_xfer_live_readonly_partial): Likewise.
	(remote_read_bytes): New, factored out from
	memory_xfer_partial_1.
This commit is contained in:
Yao Qi 2014-03-11 10:47:48 +08:00
parent 25d743f9e6
commit 8acf9577e5
5 changed files with 185 additions and 143 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
gdb/ChangeLog
View file

@ -1,3 +1,17 @@
2014-03-22 Yao Qi <yao@codesourcery.com>
* ctf.c (ctf_xfer_partial): Check the return value of
exec_read_partial_read_only, if it is not TARGET_XFER_OK,
return TARGET_XFER_UNAVAILABLE.
* tracefile-tfile.c (tfile_xfer_partial): Likewise.
* target.c (target_read_live_memory): Move it to remote.c.
(memory_xfer_live_readonly_partial): Likewise.
(memory_xfer_partial_1): Move some code to remote_read_bytes.
* remote.c (target_read_live_memory): Moved from target.c.
(memory_xfer_live_readonly_partial): Likewise.
(remote_read_bytes): Factored out from
memory_xfer_partial_1.
2014-03-21 Daniel Gutson <daniel.gutson@tallertechnologies.com>
* extension.c (eval_ext_lang_from_control_command): Avoid dereferencing

16
gdb/ctf.c
View file

@ -1377,6 +1377,7 @@ ctf_xfer_partial (struct target_ops *ops, enum target_object object,
{
struct bt_iter_pos *pos;
int i = 0;
enum target_xfer_status res;
gdb_assert (ctf_iter != NULL);
/* Save the current position. */
@ -1466,7 +1467,20 @@ ctf_xfer_partial (struct target_ops *ops, enum target_object object,
/* Restore the position. */
bt_iter_set_pos (bt_ctf_get_iter (ctf_iter), pos);
return exec_read_partial_read_only (readbuf, offset, len, xfered_len);
/* Requested memory is unavailable in the context of traceframes,
and this address falls within a read-only section, fallback
to reading from executable. */
res = exec_read_partial_read_only (readbuf, offset, len, xfered_len);
if (res == TARGET_XFER_OK)
return TARGET_XFER_OK;
else
{
/* No use trying further, we know some memory starting
at MEMADDR isn't available. */
*xfered_len = len;
return TARGET_XFER_UNAVAILABLE;
}
}
else
{

144
gdb/remote.c
View file

@ -6824,6 +6824,87 @@ remote_write_bytes (CORE_ADDR memaddr, const gdb_byte *myaddr, ULONGEST len,
packet_format[0], 1);
}
/* Read memory from the live target, even if currently inspecting a
traceframe. The return is the same as that of target_read. */
static enum target_xfer_status
target_read_live_memory (enum target_object object,
ULONGEST memaddr, gdb_byte *myaddr, ULONGEST len,
ULONGEST *xfered_len)
{
enum target_xfer_status ret;
struct cleanup *cleanup;
/* Switch momentarily out of tfind mode so to access live memory.
Note that this must not clear global state, such as the frame
cache, which must still remain valid for the previous traceframe.
We may be _building_ the frame cache at this point. */
cleanup = make_cleanup_restore_traceframe_number ();
set_traceframe_number (-1);
ret = target_xfer_partial (current_target.beneath, object, NULL,
myaddr, NULL, memaddr, len, xfered_len);
do_cleanups (cleanup);
return ret;
}
/* Using the set of read-only target sections of OPS, read live
read-only memory. Note that the actual reads start from the
top-most target again.
For interface/parameters/return description see target.h,
to_xfer_partial. */
static enum target_xfer_status
memory_xfer_live_readonly_partial (struct target_ops *ops,
enum target_object object,
gdb_byte *readbuf, ULONGEST memaddr,
ULONGEST len, ULONGEST *xfered_len)
{
struct target_section *secp;
struct target_section_table *table;
secp = target_section_by_addr (ops, memaddr);
if (secp != NULL
&& (bfd_get_section_flags (secp->the_bfd_section->owner,
secp->the_bfd_section)
& SEC_READONLY))
{
struct target_section *p;
ULONGEST memend = memaddr + len;
table = target_get_section_table (ops);
for (p = table->sections; p < table->sections_end; p++)
{
if (memaddr >= p->addr)
{
if (memend <= p->endaddr)
{
/* Entire transfer is within this section. */
return target_read_live_memory (object, memaddr,
readbuf, len, xfered_len);
}
else if (memaddr >= p->endaddr)
{
/* This section ends before the transfer starts. */
continue;
}
else
{
/* This section overlaps the transfer. Just do half. */
len = p->endaddr - memaddr;
return target_read_live_memory (object, memaddr,
readbuf, len, xfered_len);
}
}
}
}
return TARGET_XFER_EOF;
}
/* Read memory data directly from the remote machine.
This does not use the data cache; the data cache uses this.
MEMADDR is the address in the remote memory space.
@ -6835,8 +6916,8 @@ remote_write_bytes (CORE_ADDR memaddr, const gdb_byte *myaddr, ULONGEST len,
transferred in *XFERED_LEN. */
static enum target_xfer_status
remote_read_bytes (CORE_ADDR memaddr, gdb_byte *myaddr, ULONGEST len,
ULONGEST *xfered_len)
remote_read_bytes (struct target_ops *ops, CORE_ADDR memaddr,
gdb_byte *myaddr, ULONGEST len, ULONGEST *xfered_len)
{
struct remote_state *rs = get_remote_state ();
int max_buf_size; /* Max size of packet output buffer. */
@ -6847,6 +6928,63 @@ remote_read_bytes (CORE_ADDR memaddr, gdb_byte *myaddr, ULONGEST len,
if (len == 0)
return 0;
if (get_traceframe_number () != -1)
{
VEC(mem_range_s) *available;
/* If we fail to get the set of available memory, then the
target does not support querying traceframe info, and so we
attempt reading from the traceframe anyway (assuming the
target implements the old QTro packet then). */
if (traceframe_available_memory (&available, memaddr, len))
{
struct cleanup *old_chain;
old_chain = make_cleanup (VEC_cleanup(mem_range_s), &available);
if (VEC_empty (mem_range_s, available)
|| VEC_index (mem_range_s, available, 0)->start != memaddr)
{
enum target_xfer_status res;
/* Don't read into the traceframe's available
memory. */
if (!VEC_empty (mem_range_s, available))
{
LONGEST oldlen = len;
len = VEC_index (mem_range_s, available, 0)->start - memaddr;
gdb_assert (len <= oldlen);
}
do_cleanups (old_chain);
/* This goes through the topmost target again. */
res = memory_xfer_live_readonly_partial (ops,
TARGET_OBJECT_MEMORY,
myaddr, memaddr,
len, xfered_len);
if (res == TARGET_XFER_OK)
return TARGET_XFER_OK;
else
{
/* No use trying further, we know some memory starting
at MEMADDR isn't available. */
*xfered_len = len;
return TARGET_XFER_UNAVAILABLE;
}
}
/* Don't try to read more than how much is available, in
case the target implements the deprecated QTro packet to
cater for older GDBs (the target's knowledge of read-only
sections may be outdated by now). */
len = VEC_index (mem_range_s, available, 0)->length;
do_cleanups (old_chain);
}
}
max_buf_size = get_memory_read_packet_size ();
/* The packet buffer will be large enough for the payload;
get_memory_packet_size ensures this. */
@ -8698,7 +8836,7 @@ remote_xfer_partial (struct target_ops *ops, enum target_object object,
if (writebuf != NULL)
return remote_write_bytes (offset, writebuf, len, xfered_len);
else
return remote_read_bytes (offset, readbuf, len, xfered_len);
return remote_read_bytes (ops, offset, readbuf, len, xfered_len);
}
/* Handle SPU memory using qxfer packets. */

138
gdb/target.c
View file

@ -940,87 +940,6 @@ target_section_by_addr (struct target_ops *target, CORE_ADDR addr)
return NULL;
}
/* Read memory from the live target, even if currently inspecting a
traceframe. The return is the same as that of target_read. */
static enum target_xfer_status
target_read_live_memory (enum target_object object,
ULONGEST memaddr, gdb_byte *myaddr, ULONGEST len,
ULONGEST *xfered_len)
{
enum target_xfer_status ret;
struct cleanup *cleanup;
/* Switch momentarily out of tfind mode so to access live memory.
Note that this must not clear global state, such as the frame
cache, which must still remain valid for the previous traceframe.
We may be _building_ the frame cache at this point. */
cleanup = make_cleanup_restore_traceframe_number ();
set_traceframe_number (-1);
ret = target_xfer_partial (current_target.beneath, object, NULL,
myaddr, NULL, memaddr, len, xfered_len);
do_cleanups (cleanup);
return ret;
}
/* Using the set of read-only target sections of OPS, read live
read-only memory. Note that the actual reads start from the
top-most target again.
For interface/parameters/return description see target.h,
to_xfer_partial. */
static enum target_xfer_status
memory_xfer_live_readonly_partial (struct target_ops *ops,
enum target_object object,
gdb_byte *readbuf, ULONGEST memaddr,
ULONGEST len, ULONGEST *xfered_len)
{
struct target_section *secp;
struct target_section_table *table;
secp = target_section_by_addr (ops, memaddr);
if (secp != NULL
&& (bfd_get_section_flags (secp->the_bfd_section->owner,
secp->the_bfd_section)
& SEC_READONLY))
{
struct target_section *p;
ULONGEST memend = memaddr + len;
table = target_get_section_table (ops);
for (p = table->sections; p < table->sections_end; p++)
{
if (memaddr >= p->addr)
{
if (memend <= p->endaddr)
{
/* Entire transfer is within this section. */
return target_read_live_memory (object, memaddr,
readbuf, len, xfered_len);
}
else if (memaddr >= p->endaddr)
{
/* This section ends before the transfer starts. */
continue;
}
else
{
/* This section overlaps the transfer. Just do half. */
len = p->endaddr - memaddr;
return target_read_live_memory (object, memaddr,
readbuf, len, xfered_len);
}
}
}
}
return TARGET_XFER_EOF;
}
/* Read memory from more than one valid target. A core file, for
instance, could have some of memory but delegate other bits to
the target below it. So, we must manually try all targets. */
@ -1128,63 +1047,6 @@ memory_xfer_partial_1 (struct target_ops *ops, enum target_object object,
}
}
/* If reading unavailable memory in the context of traceframes, and
this address falls within a read-only section, fallback to
reading from live memory. */
if (readbuf != NULL && get_traceframe_number () != -1)
{
VEC(mem_range_s) *available;
/* If we fail to get the set of available memory, then the
target does not support querying traceframe info, and so we
attempt reading from the traceframe anyway (assuming the
target implements the old QTro packet then). */
if (traceframe_available_memory (&available, memaddr, len))
{
struct cleanup *old_chain;
old_chain = make_cleanup (VEC_cleanup(mem_range_s), &available);
if (VEC_empty (mem_range_s, available)
|| VEC_index (mem_range_s, available, 0)->start != memaddr)
{
/* Don't read into the traceframe's available
memory. */
if (!VEC_empty (mem_range_s, available))
{
LONGEST oldlen = len;
len = VEC_index (mem_range_s, available, 0)->start - memaddr;
gdb_assert (len <= oldlen);
}
do_cleanups (old_chain);
/* This goes through the topmost target again. */
res = memory_xfer_live_readonly_partial (ops, object,
readbuf, memaddr,
len, xfered_len);
if (res == TARGET_XFER_OK)
return TARGET_XFER_OK;
else
{
/* No use trying further, we know some memory starting
at MEMADDR isn't available. */
*xfered_len = len;
return TARGET_XFER_UNAVAILABLE;
}
}
/* Don't try to read more than how much is available, in
case the target implements the deprecated QTro packet to
cater for older GDBs (the target's knowledge of read-only
sections may be outdated by now). */
len = VEC_index (mem_range_s, available, 0)->length;
do_cleanups (old_chain);
}
}
/* Try GDB's internal data cache. */
region = lookup_mem_region (memaddr);
/* region->hi == 0 means there's no upper bound. */

16
gdb/tracefile-tfile.c
View file

@ -900,6 +900,7 @@ tfile_xfer_partial (struct target_ops *ops, enum target_object object,
if (get_traceframe_number () != -1)
{
int pos = 0;
enum target_xfer_status res;
/* Iterate through the traceframe's blocks, looking for
memory. */
@ -937,7 +938,20 @@ tfile_xfer_partial (struct target_ops *ops, enum target_object object,
pos += (8 + 2 + mlen);
}
return exec_read_partial_read_only (readbuf, offset, len, xfered_len);
/* Requested memory is unavailable in the context of traceframes,
and this address falls within a read-only section, fallback
to reading from executable. */
res = exec_read_partial_read_only (readbuf, offset, len, xfered_len);
if (res == TARGET_XFER_OK)
return TARGET_XFER_OK;
else
{
/* No use trying further, we know some memory starting
at MEMADDR isn't available. */
*xfered_len = len;
return TARGET_XFER_UNAVAILABLE;
}
}
else
{