[RFA] i386/amd64 h/w watchpoints in gdbserver
Doug Evans
dje@google.com
Mon May 18 23:11:00 GMT 2009
Ping.
[for completeness sake, Pierre, I haven't forgotten about win32-i386-low.c. :-)]
What can I do so that we can make some progress here?
On Thu, Apr 30, 2009 at 12:18 AM, Doug Evans <dje@google.com> wrote:
> Hi.
>
> I took Pierre's patch here
> http://sourceware.org/ml/gdb-patches/2009-02/msg00206.html
>
> and added support for {i386,amd64}-linux.
> Pierre, I _think_ I didn't break win32 support, but it is different
> than what you originally wrote. Can you test it?
>
> This patch assumes the gdbserver memory leak fix has been applied:
> http://sourceware.org/ml/gdb-patches/2009-04/msg00803.html
>
>
> 2009-04-29 Pierre Muller <muller@ics.u-strasbg.fr>
> Doug Evans <dje@google.com>
>
> * Makefile.in (SFILES): Add i386-low.c
> (i386_low_h): Define.
> (i386-low.o): Add dependencies.
> (linux-i386-low.o): Add i386-low.h dependency.
> (linux-x86-64-low.o): Ditto.
> (win32-i386-low.o): Ditto.
> * i386-low.c: New file.
> * i386-low.h: New file.
> * configure.srv (i[34567]86-*-cygwin*): Add i386-low.o to srv_tgtobj.
> (i[34567]86-*-linux*, i[34567]86-*-mingw*, x86_64-*-linux*): Ditto.
> * linux-i386-low.c: Include stddef.h, i386-low.h.
> (arch_process_info): New struct.
> (i386_linux_dr_get, i386_linux_dr_set): New functions.
> (i386_dr_low_set_addr, i386_dr_low_set_control): New functions.
> (i386_dr_low_get_status): New function.
> (i386_insert_watchpoint, i386_remove_watchpoint): New functions.
> (i386_stopped_by_watchpoint, i386_stopped_data_address): New functions.
> (i386_linux_new_process, i386_linux_new_thread): New functions.
> (the_low_target): Add entries for insert_watchpoint, remove_watchpoint,
> stopped_by_watchpoint, stopped_data_address, new_process, new_thread.
> * linux-low.c (linux_add_process): Initialize arch_private.
> (linux_remove_process): Free arch_private.
> (notify_low_target_new_thread): New function.
> (handle_extended_wait): Call it.
> (linux_attach_lwp_1, linux_wait_1): Ditto.
> (linux_insert_watchpoint): Update call to
> the_low_target.insert_watchpoint.
> (linux_remove_watchpoint): Update call to
> the_low_target.remove_watchpoint.
> (linux_stopped_by_watchpoint): Update call to
> the_low_target.stopped_by_watchpoint.
> (linux_stopped_data_address): Update call to
> the_low_target.stopped_data_address.
> * linux-low.h (process_info_private): New member arch_private.
> (linux_target_ops): Add arch_private parameter to insert_watchpoint,
> remove_watchpoint, stopped_by_watchpoint, stopped_data_address.
> New members new_process, new_thread.
> (ptid_of, PIDGET, TIDGET): New macros.
> * linux-x86-64-low.c: Include stddef.h, i386-low.h.
> (arch_process_info): New struct.
> (x86_64_linux_dr_get, x86_64_linux_dr_set): New functions.
> (i386_dr_low_set_addr, i386_dr_low_set_control): New functions.
> (i386_dr_low_get_status): New function.
> (x86_64_insert_watchpoint, x86_64_remove_watchpoint): New functions.
> (x86_64_stopped_by_watchpoint): New function.
> (x86_64_stopped_data_address): New function.
> (x86_64_linux_new_process, x86_64_linux_new_thread): New functions.
> (the_low_target): Add entries for insert_watchpoint, remove_watchpoint,
> stopped_by_watchpoint, stopped_data_address, new_process, new_thread.
> * server.h (paddr): Declare.
> * utils.c (NUMCELLS, CELLSIZE): New macros.
> (get_sell, xsnprintf, paddr): New functions.
> * win32-arm-low.c (the_low_target): Add entries for insert_watchpoint,
> remove_watchpoint, stopped_by_watchpoint, stopped_data_address.
> * win32-i386-low.c: Include i386-low.h.
> (i386_dr_low_set_addr, i386_dr_low_set_control): New functions.
> (i386_dr_low_get_status): New function.
> (the_low_target): Add entries for insert_watchpoint,
> remove_watchpoint, stopped_by_watchpoint, stopped_data_address.
> * win32-low.c (win32_insert_watchpoint): New function.
> (win32_remove_watchpoint): New function.
> (win32_stopped_by_watchpoint): New function.
> (win32_stopped_data_address): New function.
> (win32_target_ops): Add entries for insert_watchpoint,
> remove_watchpoint, stopped_by_watchpoint, stopped_data_address.
> * win32-low.h (win32_target_ops): New members insert_watchpoint,
> remove_watchpoint, stopped_by_watchpoint, stopped_data_address.
>
> Index: Makefile.in
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/Makefile.in,v
> retrieving revision 1.73
> diff -u -p -r1.73 Makefile.in
> --- Makefile.in 1 Apr 2009 22:48:05 -0000 1.73
> +++ Makefile.in 30 Apr 2009 01:23:29 -0000
> @@ -104,7 +104,7 @@ SFILES= $(srcdir)/gdbreplay.c $(srcdir)/
> $(srcdir)/thread-db.c $(srcdir)/utils.c \
> $(srcdir)/linux-arm-low.c $(srcdir)/linux-cris-low.c \
> $(srcdir)/linux-crisv32-low.c $(srcdir)/linux-i386-low.c \
> - $(srcdir)/i387-fp.c \
> + ${srcdir}/i386-low.c $(srcdir)/i387-fp.c \
> $(srcdir)/linux-ia64-low.c $(srcdir)/linux-low.c \
> $(srcdir)/linux-m32r-low.c \
> $(srcdir)/linux-m68k-low.c $(srcdir)/linux-mips-low.c \
> @@ -287,6 +287,10 @@ signals.o: ../common/signals.c $(server_
> memmem.o: ../gnulib/memmem.c
> $(CC) -o memmem.o -c $(CPPFLAGS) $(INTERNAL_CFLAGS) $<
>
> +i386_low_h = $(srcdir)/i386-low.h
> +
> +i386-low.o: i386-low.c $(i386_low_h) $(server_h) $(target_h)
> +
> i387-fp.o: i387-fp.c $(server_h)
>
> linux-low.o: linux-low.c $(linux_low_h) $(server_h)
> @@ -297,7 +301,7 @@ linux-arm-low.o: linux-arm-low.c $(linux
> linux-cris-low.o: linux-cris-low.c $(linux_low_h) $(server_h)
> linux-crisv32-low.o: linux-crisv32-low.c $(linux_low_h) $(server_h)
> linux-i386-low.o: linux-i386-low.c $(linux_low_h) $(server_h) \
> - $(gdb_proc_service_h)
> + $(gdb_proc_service_h) $(i386_low_h)
> linux-ia64-low.o: linux-ia64-low.c $(linux_low_h) $(server_h)
> linux-m32r-low.o: linux-m32r-low.c $(linux_low_h) $(server_h)
> linux-mips-low.o: linux-mips-low.c $(linux_low_h) $(server_h) \
> @@ -306,7 +310,7 @@ linux-ppc-low.o: linux-ppc-low.c $(linux
> linux-s390-low.o: linux-s390-low.c $(linux_low_h) $(server_h)
> linux-sh-low.o: linux-sh-low.c $(linux_low_h) $(server_h)
> linux-x86-64-low.o: linux-x86-64-low.c $(linux_low_h) $(server_h) \
> - $(gdb_proc_service_h)
> + $(gdb_proc_service_h) $(i386_low_h)
> linux-xtensa-low.o: linux-xtensa-low.c xtensa-xtregs.c $(linux_low_h) $(server_h)
>
> win32_low_h = $(srcdir)/win32-low.h
> @@ -314,7 +318,7 @@ win32_low_h = $(srcdir)/win32-low.h
> win32-low.o: win32-low.c $(win32_low_h) $(server_h) $(regdef_h) $(regcache_h)
>
> win32-arm-low.o: win32-arm-low.c $(win32_low_h) $(server_h)
> -win32-i386-low.o: win32-i386-low.c $(win32_low_h) $(server_h)
> +win32-i386-low.o: win32-i386-low.c $(win32_low_h) $(server_h) $(i386_low_h)
>
> spu-low.o: spu-low.c $(server_h)
>
> Index: configure.srv
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/configure.srv,v
> retrieving revision 1.40
> diff -u -p -r1.40 configure.srv
> --- configure.srv 19 Apr 2009 17:54:52 -0000 1.40
> +++ configure.srv 30 Apr 2009 01:23:29 -0000
> @@ -53,10 +53,10 @@ case "${target}" in
> srv_linux_thread_db=yes
> ;;
> i[34567]86-*-cygwin*) srv_regobj=reg-i386.o
> - srv_tgtobj="win32-low.o win32-i386-low.o"
> + srv_tgtobj="i386-low.o win32-low.o win32-i386-low.o"
> ;;
> i[34567]86-*-linux*) srv_regobj=reg-i386-linux.o
> - srv_tgtobj="linux-low.o linux-i386-low.o i387-fp.o"
> + srv_tgtobj="linux-low.o linux-i386-low.o i386-low.o i387-fp.o"
> srv_linux_usrregs=yes
> srv_linux_regsets=yes
> srv_linux_thread_db=yes
> @@ -71,7 +71,7 @@ case "${target}" in
> srv_mingwce=yes
> ;;
> i[34567]86-*-mingw*) srv_regobj=reg-i386.o
> - srv_tgtobj="win32-low.o win32-i386-low.o"
> + srv_tgtobj="i386-low.o win32-low.o win32-i386-low.o"
> srv_mingw=yes
> ;;
> ia64-*-linux*) srv_regobj=reg-ia64.o
> @@ -170,7 +170,7 @@ case "${target}" in
> srv_tgtobj="spu-low.o"
> ;;
> x86_64-*-linux*) srv_regobj=reg-x86-64-linux.o
> - srv_tgtobj="linux-low.o linux-x86-64-low.o i387-fp.o"
> + srv_tgtobj="linux-low.o linux-x86-64-low.o i386-low.o i387-fp.o"
> srv_linux_regsets=yes
> srv_linux_thread_db=yes
> ;;
> Index: i386-low.c
> ===================================================================
> RCS file: i386-low.c
> diff -N i386-low.c
> --- /dev/null 1 Jan 1970 00:00:00 -0000
> +++ i386-low.c 30 Apr 2009 01:23:29 -0000
> @@ -0,0 +1,667 @@
> +/* Debug register code for the i386.
> +
> + Copyright (C) 2009
> + Free Software Foundation, Inc.
> +
> + This file is part of GDB.
> +
> + This program is free software; you can redistribute it and/or modify
> + it under the terms of the GNU General Public License as published by
> + the Free Software Foundation; either version 3 of the License, or
> + (at your option) any later version.
> +
> + This program is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + GNU General Public License for more details.
> +
> + You should have received a copy of the GNU General Public License
> + along with this program. If not, see <http://www.gnu.org/licenses/>. */
> +
> +#include "server.h"
> +#include "target.h"
> +#include "i386-low.h"
> +
> +/* Support for 8-byte wide hw watchpoints. */
> +#ifndef TARGET_HAS_DR_LEN_8
> +#define TARGET_HAS_DR_LEN_8 (sizeof (long) == 8)
> +#endif
> +
> +enum target_hw_bp_type
> + {
> + hw_write = 0, /* Common HW watchpoint */
> + hw_read = 1, /* Read HW watchpoint */
> + hw_access = 2, /* Access HW watchpoint */
> + hw_execute = 3 /* Execute HW breakpoint */
> + };
> +
> +/* DR7 Debug Control register fields. */
> +
> +/* How many bits to skip in DR7 to get to R/W and LEN fields. */
> +#define DR_CONTROL_SHIFT 16
> +/* How many bits in DR7 per R/W and LEN field for each watchpoint. */
> +#define DR_CONTROL_SIZE 4
> +
> +/* Watchpoint/breakpoint read/write fields in DR7. */
> +#define DR_RW_EXECUTE (0x0) /* Break on instruction execution. */
> +#define DR_RW_WRITE (0x1) /* Break on data writes. */
> +#define DR_RW_READ (0x3) /* Break on data reads or writes. */
> +
> +/* This is here for completeness. No platform supports this
> + functionality yet (as of March 2001). Note that the DE flag in the
> + CR4 register needs to be set to support this. */
> +#ifndef DR_RW_IORW
> +#define DR_RW_IORW (0x2) /* Break on I/O reads or writes. */
> +#endif
> +
> +/* Watchpoint/breakpoint length fields in DR7. The 2-bit left shift
> + is so we could OR this with the read/write field defined above. */
> +#define DR_LEN_1 (0x0 << 2) /* 1-byte region watch or breakpoint. */
> +#define DR_LEN_2 (0x1 << 2) /* 2-byte region watch. */
> +#define DR_LEN_4 (0x3 << 2) /* 4-byte region watch. */
> +#define DR_LEN_8 (0x2 << 2) /* 8-byte region watch (AMD64). */
> +
> +/* Local and Global Enable flags in DR7.
> +
> + When the Local Enable flag is set, the breakpoint/watchpoint is
> + enabled only for the current task; the processor automatically
> + clears this flag on every task switch. When the Global Enable flag
> + is set, the breakpoint/watchpoint is enabled for all tasks; the
> + processor never clears this flag.
> +
> + Currently, all watchpoint are locally enabled. If you need to
> + enable them globally, read the comment which pertains to this in
> + i386_insert_aligned_watchpoint below. */
> +#define DR_LOCAL_ENABLE_SHIFT 0 /* Extra shift to the local enable bit. */
> +#define DR_GLOBAL_ENABLE_SHIFT 1 /* Extra shift to the global enable bit. */
> +#define DR_ENABLE_SIZE 2 /* Two enable bits per debug register. */
> +
> +/* Local and global exact breakpoint enable flags (a.k.a. slowdown
> + flags). These are only required on i386, to allow detection of the
> + exact instruction which caused a watchpoint to break; i486 and
> + later processors do that automatically. We set these flags for
> + backwards compatibility. */
> +#define DR_LOCAL_SLOWDOWN (0x100)
> +#define DR_GLOBAL_SLOWDOWN (0x200)
> +
> +/* Fields reserved by Intel. This includes the GD (General Detect
> + Enable) flag, which causes a debug exception to be generated when a
> + MOV instruction accesses one of the debug registers.
> +
> + FIXME: My Intel manual says we should use 0xF800, not 0xFC00. */
> +#define DR_CONTROL_RESERVED (0xFC00)
> +
> +/* Auxiliary helper macros. */
> +
> +/* A value that masks all fields in DR7 that are reserved by Intel. */
> +#define I386_DR_CONTROL_MASK (~DR_CONTROL_RESERVED)
> +
> +/* The I'th debug register is vacant if its Local and Global Enable
> + bits are reset in the Debug Control register. */
> +#define I386_DR_VACANT(state, i) \
> + (((state)->dr_control_mirror & (3 << (DR_ENABLE_SIZE * (i)))) == 0)
> +
> +/* Locally enable the break/watchpoint in the I'th debug register. */
> +#define I386_DR_LOCAL_ENABLE(state, i) \
> + do { \
> + (state)->dr_control_mirror |= \
> + (1 << (DR_LOCAL_ENABLE_SHIFT + DR_ENABLE_SIZE * (i))); \
> + } while (0)
> +
> +/* Globally enable the break/watchpoint in the I'th debug register. */
> +#define I386_DR_GLOBAL_ENABLE(state, i) \
> + do { \
> + (state)->dr_control_mirror |= \
> + (1 << (DR_GLOBAL_ENABLE_SHIFT + DR_ENABLE_SIZE * (i))); \
> + } while (0)
> +
> +/* Disable the break/watchpoint in the I'th debug register. */
> +#define I386_DR_DISABLE(state, i) \
> + do { \
> + (state)->dr_control_mirror &= \
> + ~(3 << (DR_ENABLE_SIZE * (i))); \
> + } while (0)
> +
> +/* Set in DR7 the RW and LEN fields for the I'th debug register. */
> +#define I386_DR_SET_RW_LEN(state, i,rwlen) \
> + do { \
> + (state)->dr_control_mirror &= \
> + ~(0x0f << (DR_CONTROL_SHIFT+DR_CONTROL_SIZE*(i))); \
> + (state)->dr_control_mirror |= \
> + ((rwlen) << (DR_CONTROL_SHIFT+DR_CONTROL_SIZE*(i))); \
> + } while (0)
> +
> +/* Get from DR7 the RW and LEN fields for the I'th debug register. */
> +#define I386_DR_GET_RW_LEN(state, i) \
> + (((state)->dr_control_mirror >> (DR_CONTROL_SHIFT + DR_CONTROL_SIZE * (i))) & 0x0f)
> +
> +/* Did the watchpoint whose address is in the I'th register break? */
> +#define I386_DR_WATCH_HIT(state,i) ((state)->dr_status_mirror & (1 << (i)))
> +
> +/* A macro to loop over all debug registers. */
> +#define ALL_DEBUG_REGISTERS(i) for (i = 0; i < DR_NADDR; i++)
> +
> +/* Whether or not to print the mirrored debug registers. */
> +static int maint_show_dr = 0;
> +
> +/* Types of operations supported by i386_handle_nonaligned_watchpoint. */
> +typedef enum { WP_INSERT, WP_REMOVE, WP_COUNT } i386_wp_op_t;
> +
> +/* Internal functions. */
> +
> +/* Return the value of a 4-bit field for DR7 suitable for watching a
> + region of LEN bytes for accesses of type TYPE. LEN is assumed to
> + have the value of 1, 2, or 4. */
> +static unsigned i386_length_and_rw_bits (int len, enum target_hw_bp_type type);
> +
> +/* Insert a watchpoint at address ADDR, which is assumed to be aligned
> + according to the length of the region to watch. LEN_RW_BITS is the
> + value of the bit-field from DR7 which describes the length and
> + access type of the region to be watched by this watchpoint. Return
> + 0 on success, -1 on failure. */
> +static int i386_insert_aligned_watchpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr,
> + unsigned len_rw_bits);
> +
> +/* Remove a watchpoint at address ADDR, which is assumed to be aligned
> + according to the length of the region to watch. LEN_RW_BITS is the
> + value of the bits from DR7 which describes the length and access
> + type of the region watched by this watchpoint. Return 0 on
> + success, -1 on failure. */
> +static int i386_remove_aligned_watchpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr,
> + unsigned len_rw_bits);
> +
> +/* Insert or remove a (possibly non-aligned) watchpoint, or count the
> + number of debug registers required to watch a region at address
> + ADDR whose length is LEN for accesses of type TYPE. Return 0 on
> + successful insertion or removal, a positive number when queried
> + about the number of registers, or -1 on failure. If WHAT is not a
> + valid value, bombs through internal_error. */
> +static int i386_handle_nonaligned_watchpoint (struct i386_debug_reg_state *state,
> + i386_wp_op_t what,
> + CORE_ADDR addr, int len,
> + enum target_hw_bp_type type);
> +
> +/* Implementation. */
> +
> +/* Clear the reference counts and forget everything we knew about the
> + debug registers. */
> +
> +void
> +i386_low_cleanup_dregs (struct i386_debug_reg_state *state)
> +{
> + int i;
> +
> + ALL_DEBUG_REGISTERS(i)
> + {
> + state->dr_mirror[i] = 0;
> + state->dr_ref_count[i] = 0;
> + }
> + state->dr_control_mirror = 0;
> + state->dr_status_mirror = 0;
> +}
> +
> +/* Print the values of the mirrored debug registers. This is called
> + when maint_show_dr is non-zero. To set that up, type "maint
> + show-debug-regs" at GDB's prompt. */
> +
> +static void
> +i386_show_dr (struct i386_debug_reg_state *state,
> + const char *func, CORE_ADDR addr,
> + int len, enum target_hw_bp_type type)
> +{
> + int i;
> +
> + printf (func);
> + if (addr || len)
> + printf (" (addr=%lx, len=%d, type=%s)",
> + (unsigned long) addr, len,
> + type == hw_write ? "data-write"
> + : (type == hw_read ? "data-read"
> + : (type == hw_access ? "data-read/write"
> + : (type == hw_execute ? "instruction-execute"
> + /* FIXME: if/when I/O read/write
> + watchpoints are supported, add them
> + here. */
> + : "??unknown??"))));
> + printf (":\n");
> + printf ("\tCONTROL (DR7): %08x STATUS (DR6): %08x\n",
> + state->dr_control_mirror, state->dr_status_mirror);
> + ALL_DEBUG_REGISTERS (i)
> + {
> + printf ("\
> +\tDR%d: addr=0x%s, ref.count=%d DR%d: addr=0x%s, ref.count=%d\n",
> + i, paddr (state->dr_mirror[i]), state->dr_ref_count[i],
> + i+1, paddr (state->dr_mirror[i+1]), state->dr_ref_count[i+1]);
> + i++;
> + }
> +}
> +
> +/* Return the value of a 4-bit field for DR7 suitable for watching a
> + region of LEN bytes for accesses of type TYPE. LEN is assumed to
> + have the value of 1, 2, or 4. */
> +
> +static unsigned
> +i386_length_and_rw_bits (int len, enum target_hw_bp_type type)
> +{
> + unsigned rw;
> +
> + switch (type)
> + {
> + case hw_execute:
> + rw = DR_RW_EXECUTE;
> + break;
> + case hw_write:
> + rw = DR_RW_WRITE;
> + break;
> + case hw_read:
> + /* The i386 doesn't support data-read watchpoints. */
> + case hw_access:
> + rw = DR_RW_READ;
> + break;
> +#if 0
> + /* Not yet supported. */
> + case hw_io_access:
> + rw = DR_RW_IORW;
> + break;
> +#endif
> + default:
> + error ("\
> +Invalid hardware breakpoint type %d in i386_length_and_rw_bits.\n",
> + (int) type);
> + }
> +
> + switch (len)
> + {
> + case 1:
> + return (DR_LEN_1 | rw);
> + case 2:
> + return (DR_LEN_2 | rw);
> + case 4:
> + return (DR_LEN_4 | rw);
> + case 8:
> + if (TARGET_HAS_DR_LEN_8)
> + return (DR_LEN_8 | rw);
> + default:
> + error ("\
> +Invalid hardware breakpoint length %d in i386_length_and_rw_bits.\n", len);
> + }
> +}
> +
> +/* Insert a watchpoint at address ADDR, which is assumed to be aligned
> + according to the length of the region to watch. LEN_RW_BITS is the
> + value of the bits from DR7 which describes the length and access
> + type of the region to be watched by this watchpoint. Return 0 on
> + success, -1 on failure. */
> +
> +static int
> +i386_insert_aligned_watchpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr, unsigned len_rw_bits)
> +{
> + int i;
> +
> + /* First, look for an occupied debug register with the same address
> + and the same RW and LEN definitions. If we find one, we can
> + reuse it for this watchpoint as well (and save a register). */
> + ALL_DEBUG_REGISTERS(i)
> + {
> + if (!I386_DR_VACANT (state, i)
> + && state->dr_mirror[i] == addr
> + && I386_DR_GET_RW_LEN (state, i) == len_rw_bits)
> + {
> + state->dr_ref_count[i]++;
> + return 0;
> + }
> + }
> +
> + /* Next, look for a vacant debug register. */
> + ALL_DEBUG_REGISTERS(i)
> + {
> + if (I386_DR_VACANT (state, i))
> + break;
> + }
> +
> + /* No more debug registers! */
> + if (i >= DR_NADDR)
> + return -1;
> +
> + /* Now set up the register I to watch our region. */
> +
> + /* Record the info in our local mirrored array. */
> + state->dr_mirror[i] = addr;
> + state->dr_ref_count[i] = 1;
> + I386_DR_SET_RW_LEN (state, i, len_rw_bits);
> + /* Note: we only enable the watchpoint locally, i.e. in the current
> + task. Currently, no i386 target allows or supports global
> + watchpoints; however, if any target would want that in the
> + future, GDB should probably provide a command to control whether
> + to enable watchpoints globally or locally, and the code below
> + should use global or local enable and slow-down flags as
> + appropriate. */
> + I386_DR_LOCAL_ENABLE (state, i);
> + state->dr_control_mirror |= DR_LOCAL_SLOWDOWN;
> + state->dr_control_mirror &= I386_DR_CONTROL_MASK;
> +
> + /* Finally, actually pass the info to the inferior. */
> + i386_dr_low_set_addr (i, addr);
> + i386_dr_low_set_control (state->dr_control_mirror);
> +
> + return 0;
> +}
> +
> +/* Reset a watched address for debug reg DR.
> + All implementations just do foo_set_addr (addr, 0), so this is a wrapper
> + around foo_set_addr to maintain the concept that this is a reset. */
> +
> +static void
> +i386_dr_low_reset_addr (int dr)
> +{
> + i386_dr_low_set_addr (dr, 0);
> +}
> +
> +/* Remove a watchpoint at address ADDR, which is assumed to be aligned
> + according to the length of the region to watch. LEN_RW_BITS is the
> + value of the bits from DR7 which describes the length and access
> + type of the region watched by this watchpoint. Return 0 on
> + success, -1 on failure. */
> +
> +static int
> +i386_remove_aligned_watchpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr, unsigned len_rw_bits)
> +{
> + int i, retval = -1;
> +
> + ALL_DEBUG_REGISTERS(i)
> + {
> + if (!I386_DR_VACANT (state, i)
> + && state->dr_mirror[i] == addr
> + && I386_DR_GET_RW_LEN (state, i) == len_rw_bits)
> + {
> + if (--state->dr_ref_count[i] == 0) /* no longer in use? */
> + {
> + /* Reset our mirror. */
> + state->dr_mirror[i] = 0;
> + I386_DR_DISABLE (state, i);
> + /* Reset it in the inferior. */
> + i386_dr_low_set_control (state->dr_control_mirror);
> + i386_dr_low_reset_addr (i);
> + }
> + retval = 0;
> + }
> + }
> +
> + return retval;
> +}
> +
> +/* Insert or remove a (possibly non-aligned) watchpoint, or count the
> + number of debug registers required to watch a region at address
> + ADDR whose length is LEN for accesses of type TYPE. Return 0 on
> + successful insertion or removal, a positive number when queried
> + about the number of registers, or -1 on failure. If WHAT is not a
> + valid value, bombs through internal_error. */
> +
> +static int
> +i386_handle_nonaligned_watchpoint (struct i386_debug_reg_state *state,
> + i386_wp_op_t what, CORE_ADDR addr, int len,
> + enum target_hw_bp_type type)
> +{
> + int retval = 0, status = 0;
> + int max_wp_len = TARGET_HAS_DR_LEN_8 ? 8 : 4;
> +
> + static int size_try_array[8][8] =
> + {
> + {1, 1, 1, 1, 1, 1, 1, 1}, /* Trying size one. */
> + {2, 1, 2, 1, 2, 1, 2, 1}, /* Trying size two. */
> + {2, 1, 2, 1, 2, 1, 2, 1}, /* Trying size three. */
> + {4, 1, 2, 1, 4, 1, 2, 1}, /* Trying size four. */
> + {4, 1, 2, 1, 4, 1, 2, 1}, /* Trying size five. */
> + {4, 1, 2, 1, 4, 1, 2, 1}, /* Trying size six. */
> + {4, 1, 2, 1, 4, 1, 2, 1}, /* Trying size seven. */
> + {8, 1, 2, 1, 4, 1, 2, 1}, /* Trying size eight. */
> + };
> +
> + while (len > 0)
> + {
> + int align = addr % max_wp_len;
> + /* Four (eight on AMD64) is the maximum length a debug register
> + can watch. */
> + int try = (len > max_wp_len ? (max_wp_len - 1) : len - 1);
> + int size = size_try_array[try][align];
> +
> + if (what == WP_COUNT)
> + {
> + /* size_try_array[] is defined such that each iteration
> + through the loop is guaranteed to produce an address and a
> + size that can be watched with a single debug register.
> + Thus, for counting the registers required to watch a
> + region, we simply need to increment the count on each
> + iteration. */
> + retval++;
> + }
> + else
> + {
> + unsigned len_rw = i386_length_and_rw_bits (size, type);
> +
> + if (what == WP_INSERT)
> + status = i386_insert_aligned_watchpoint (state, addr, len_rw);
> + else if (what == WP_REMOVE)
> + status = i386_remove_aligned_watchpoint (state, addr, len_rw);
> +#if 0
> + else
> + internal_error (__FILE__, __LINE__, _("\
> +Invalid value %d of operation in i386_handle_nonaligned_watchpoint.\n"),
> + (int)what);
> +#endif
> + /* We keep the loop going even after a failure, because some
> + of the other aligned watchpoints might still succeed
> + (e.g. if they watch addresses that are already watched,
> + in which case we just increment the reference counts of
> + occupied debug registers). If we break out of the loop
> + too early, we could cause those addresses watched by
> + other watchpoints to be disabled when breakpoint.c reacts
> + to our failure to insert this watchpoint and tries to
> + remove it. */
> + if (status)
> + retval = status;
> + }
> +
> + addr += size;
> + len -= size;
> + }
> +
> + return retval;
> +}
> +
> +#define Z_PACKET_WRITE_WP '2'
> +#define Z_PACKET_READ_WP '3'
> +#define Z_PACKET_ACCESS_WP '4'
> +
> +static int
> +Z_packet_to_hw_type (char type)
> +{
> + switch (type)
> + {
> + case Z_PACKET_WRITE_WP: return hw_write;
> + case Z_PACKET_READ_WP: return hw_read;
> + case Z_PACKET_ACCESS_WP: return hw_access;
> + default:
> + error ("Z_packet_to_hw_type: bad watchpoint type %c", type);
> + }
> +}
> +
> +/* Insert a watchpoint to watch a memory region which starts at
> + address ADDR and whose length is LEN bytes. Watch memory accesses
> + of the type TYPE_FROM_PACKET. Return 0 on success, -1 on failure. */
> +
> +int
> +i386_low_insert_watchpoint (struct i386_debug_reg_state *state,
> + char type_from_packet, CORE_ADDR addr, int len)
> +{
> + int retval;
> + int type = Z_packet_to_hw_type (type_from_packet);
> +
> + if (((len != 1 && len !=2 && len !=4) && !(TARGET_HAS_DR_LEN_8 && len == 8))
> + || addr % len != 0)
> + {
> + retval = i386_handle_nonaligned_watchpoint (state, WP_INSERT,
> + addr, len, type);
> + }
> + else
> + {
> + unsigned len_rw = i386_length_and_rw_bits (len, type);
> +
> + retval = i386_insert_aligned_watchpoint (state, addr, len_rw);
> + }
> +
> + if (maint_show_dr)
> + i386_show_dr (state, "insert_watchpoint", addr, len, type);
> +
> + return retval;
> +}
> +
> +/* Remove a watchpoint that watched the memory region which starts at
> + address ADDR, whose length is LEN bytes, and for accesses of the
> + type TYPE_FROM_PACKET. Return 0 on success, -1 on failure. */
> +
> +int
> +i386_low_remove_watchpoint (struct i386_debug_reg_state *state,
> + char type_from_packet, CORE_ADDR addr, int len)
> +{
> + int retval;
> + int type = Z_packet_to_hw_type (type_from_packet);
> +
> + if (((len != 1 && len !=2 && len !=4) && !(TARGET_HAS_DR_LEN_8 && len == 8))
> + || addr % len != 0)
> + {
> + retval = i386_handle_nonaligned_watchpoint (state, WP_REMOVE,
> + addr, len, type);
> + }
> + else
> + {
> + unsigned len_rw = i386_length_and_rw_bits (len, type);
> +
> + retval = i386_remove_aligned_watchpoint (state, addr, len_rw);
> + }
> + if (maint_show_dr)
> + i386_show_dr (state, "remove_watchpoint", addr, len, type);
> + return retval;
> +}
> +
> +/* Return non-zero if we can watch a memory region that starts at
> + address ADDR and whose length is LEN bytes. */
> +
> +int
> +i386_low_region_ok_for_watchpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr, int len)
> +{
> + int nregs;
> +
> + /* Compute how many aligned watchpoints we would need to cover this
> + region. */
> + nregs = i386_handle_nonaligned_watchpoint (state, WP_COUNT,
> + addr, len, hw_write);
> + return nregs <= DR_NADDR ? 1 : 0;
> +}
> +
> +/* If the inferior has some watchpoint that triggered, set the
> + address associated with that watchpoint and return non-zero.
> + Otherwise, return zero. */
> +
> +CORE_ADDR
> +i386_low_stopped_data_address (struct i386_debug_reg_state *state)
> +{
> + CORE_ADDR addr = 0;
> + int i;
> + int rc = 0;
> +
> + state->dr_status_mirror = i386_dr_low_get_status ();
> +
> + ALL_DEBUG_REGISTERS(i)
> + {
> + if (I386_DR_WATCH_HIT (state, i)
> + /* This second condition makes sure DRi is set up for a data
> + watchpoint, not a hardware breakpoint. The reason is
> + that GDB doesn't call the target_stopped_data_address
> + method except for data watchpoints. In other words, I'm
> + being paranoiac. */
> + && I386_DR_GET_RW_LEN (state, i) != 0)
> + {
> + addr = state->dr_mirror[i];
> + rc = 1;
> + if (maint_show_dr)
> + i386_show_dr (state, "watchpoint_hit", addr, -1, hw_write);
> + }
> + }
> + if (maint_show_dr && addr == 0)
> + i386_show_dr (state, "stopped_data_addr", 0, 0, hw_write);
> +
> + /* NOTE: gdb version checks rc != 0 here. */
> + return addr;
> +}
> +
> +int
> +i386_low_stopped_by_watchpoint (struct i386_debug_reg_state *state)
> +{
> + CORE_ADDR addr = 0;
> + /* NOTE: gdb version passes boolean found/not-found result from
> + i386_stopped_data_address. */
> + addr = i386_low_stopped_data_address (state);
> + return (addr != 0);
> +}
> +
> +/* Support for h/w breakpoints.
> + This support is not currently used, kept for reference. */
> +
> +/* Return non-zero if the inferior has some break/watchpoint that
> + triggered. */
> +
> +int
> +i386_low_stopped_by_hwbp (struct i386_debug_reg_state *state)
> +{
> + int i;
> +
> + state->dr_status_mirror = i386_dr_low_get_status ();
> + if (maint_show_dr)
> + i386_show_dr (state, "stopped_by_hwbp", 0, 0, hw_execute);
> +
> + ALL_DEBUG_REGISTERS(i)
> + {
> + if (I386_DR_WATCH_HIT (state, i))
> + return 1;
> + }
> +
> + return 0;
> +}
> +
> +/* Insert a hardware-assisted breakpoint at ADDR.
> + Return 0 on success, -1 on failure. */
> +
> +int
> +i386_low_insert_hw_breakpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr)
> +{
> + unsigned len_rw = i386_length_and_rw_bits (1, hw_execute);
> + int retval = i386_insert_aligned_watchpoint (state, addr, len_rw);
> +
> + if (maint_show_dr)
> + i386_show_dr (state, "insert_hwbp", addr, 1, hw_execute);
> +
> + return retval;
> +}
> +
> +/* Remove a hardware-assisted breakpoint at ADDR.
> + Return 0 on success, -1 on failure. */
> +
> +int
> +i386_low_remove_hw_breakpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr)
> +{
> + unsigned len_rw = i386_length_and_rw_bits (1, hw_execute);
> + int retval = i386_remove_aligned_watchpoint (state, addr, len_rw);
> +
> + if (maint_show_dr)
> + i386_show_dr (state, "remove_hwbp", addr, 1, hw_execute);
> +
> + return retval;
> +}
> Index: i386-low.h
> ===================================================================
> RCS file: i386-low.h
> diff -N i386-low.h
> --- /dev/null 1 Jan 1970 00:00:00 -0000
> +++ i386-low.h 30 Apr 2009 01:23:29 -0000
> @@ -0,0 +1,118 @@
> +/* Misc. low level support for i386.
> +
> + Copyright (C) 2009
> + Free Software Foundation, Inc.
> +
> + This file is part of GDB.
> +
> + This program is free software; you can redistribute it and/or modify
> + it under the terms of the GNU General Public License as published by
> + the Free Software Foundation; either version 3 of the License, or
> + (at your option) any later version.
> +
> + This program is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + GNU General Public License for more details.
> +
> + You should have received a copy of the GNU General Public License
> + along with this program. If not, see <http://www.gnu.org/licenses/>. */
> +
> +/* Support for hardware watchpoints and breakpoints using the i386
> + debug registers.
> +
> + This provides several functions for inserting and removing
> + hardware-assisted breakpoints and watchpoints, testing if one or
> + more of the watchpoints triggered and at what address, checking
> + whether a given region can be watched, etc.
> +
> + The functions below implement debug registers sharing by reference
> + counts, and allow to watch regions up to 16 bytes long
> + (32 bytes on 64 bit hosts). */
> +
> +
> +/* Debug registers' indices. */
> +#define DR_FIRSTADDR 0
> +#define DR_LASTADDR 3
> +#define DR_NADDR 4 /* The number of debug address registers. */
> +#define DR_STATUS 6
> +#define DR_CONTROL 7
> +
> +/* Global state needed to track h/w watchpoints. */
> +
> +struct i386_debug_reg_state
> +{
> + /* Mirror the inferior's DRi registers. We keep the status and
> + control registers separated because they don't hold addresses. */
> + CORE_ADDR dr_mirror[DR_NADDR];
> + unsigned dr_status_mirror, dr_control_mirror;
> +
> + /* Reference counts for each debug register. */
> + int dr_ref_count[DR_NADDR];
> +};
> +
> +/* Clear the reference counts and forget everything we knew about DRi. */
> +extern void i386_low_cleanup_dregs (struct i386_debug_reg_state *state);
> +
> +/* Insert a watchpoint to watch a memory region which starts at
> + address ADDR and whose length is LEN bytes. Watch memory accesses
> + of the type TYPE_FROM_PACKET. Return 0 on success, -1 on failure. */
> +extern int i386_low_insert_watchpoint (struct i386_debug_reg_state *state,
> + char type_from_packet, CORE_ADDR addr,
> + int len);
> +
> +/* Remove a watchpoint that watched the memory region which starts at
> + address ADDR, whose length is LEN bytes, and for accesses of the
> + type TYPE_FROM_PACKET. Return 0 on success, -1 on failure. */
> +extern int i386_low_remove_watchpoint (struct i386_debug_reg_state *state,
> + char type_from_packet, CORE_ADDR addr,
> + int len);
> +
> +/* Return non-zero if we can watch a memory region that starts at
> + address ADDR and whose length is LEN bytes. */
> +extern int i386_low_region_ok_for_watchpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr, int len);
> +
> +/* If the inferior has some break/watchpoint that triggered, set
> + the address associated with that break/watchpoint and return
> + true. Otherwise, return false. */
> +extern CORE_ADDR i386_low_stopped_data_address (struct i386_debug_reg_state *state);
> +
> +extern int i386_low_stopped_by_watchpoint (struct i386_debug_reg_state *state);
> +
> +/* Return non-zero if the inferior has some break/watchpoint that
> + triggered. */
> +extern int i386_low_stopped_by_hwbp (struct i386_debug_reg_state *state);
> +
> +/* Insert a hardware-assisted breakpoint at ADDR.
> + Return 0 on success, -1 on failure. */
> +extern int i386_low_insert_hw_breakpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr);
> +
> +/* Remove a hardware-assisted breakpoint at ADDR.
> + Return 0 on success, -1 on failure. */
> +extern int i386_low_remove_hw_breakpoint (struct i386_debug_reg_state *state,
> + CORE_ADDR addr);
> +
> +/* Each target needs to provide several low-level functions
> + that will be called to insert watchpoints and hardware breakpoints
> + into the inferior, remove them, and check their status. These
> + functions are:
> +
> + i386_dr_low_set_control -- set the debug control (DR7)
> + register to a given value
> +
> + i386_dr_low_set_addr -- put an address into one debug register
> +
> + i386_dr_low_get_status -- return the value of the debug
> + status (DR6) register.
> +*/
> +
> +/* Pass the address ADDR to the inferior in the I'th debug register. */
> +extern void i386_dr_low_set_addr (int i, CORE_ADDR addr);
> +
> +/* Pass the value VAL to the inferior in the DR7 debug control register. */
> +extern void i386_dr_low_set_control (unsigned val);
> +
> +/* Get the value of the DR6 debug status register from the inferior. */
> +extern unsigned i386_dr_low_get_status (void);
> Index: linux-i386-low.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/linux-i386-low.c,v
> retrieving revision 1.19
> diff -u -p -r1.19 linux-i386-low.c
> --- linux-i386-low.c 22 Mar 2009 23:57:10 -0000 1.19
> +++ linux-i386-low.c 30 Apr 2009 01:23:29 -0000
> @@ -17,9 +17,11 @@
> You should have received a copy of the GNU General Public License
> along with this program. If not, see <http://www.gnu.org/licenses/>. */
>
> +#include <stddef.h>
> #include "server.h"
> #include "linux-low.h"
> #include "i387-fp.h"
> +#include "i386-low.h"
>
> #include "gdb_proc_service.h"
>
> @@ -33,10 +35,14 @@
> #define PTRACE_GET_THREAD_AREA 25
> #endif
>
> +struct arch_process_info
> +{
> + struct i386_debug_reg_state debug_reg_state;
> +};
> +
> /* Defined in auto-generated file reg-i386-linux.c. */
> void init_registers_i386_linux (void);
>
> -
> /* This module only supports access to the general purpose registers. */
>
> #define i386_num_regs 16
> @@ -187,6 +193,148 @@ i386_breakpoint_at (CORE_ADDR pc)
>
> return 0;
> }
> +
> +/* Support for debug registers. */
> +
> +static unsigned long
> +i386_linux_dr_get (ptid_t ptid, int regnum)
> +{
> + int tid;
> + unsigned long value;
> +
> + tid = TIDGET (ptid);
> + if (tid == 0)
> + tid = PIDGET (ptid);
> +
> + errno = 0;
> + value = ptrace (PTRACE_PEEKUSER, tid,
> + offsetof (struct user, u_debugreg[regnum]), 0);
> + if (errno != 0)
> + error ("Couldn't read debug register");
> +
> + return value;
> +}
> +
> +static void
> +i386_linux_dr_set (ptid_t ptid, int regnum, unsigned long value)
> +{
> + int tid;
> +
> + tid = TIDGET (ptid);
> + if (tid == 0)
> + tid = PIDGET (ptid);
> +
> + errno = 0;
> + ptrace (PTRACE_POKEUSER, tid,
> + offsetof (struct user, u_debugreg[regnum]), value);
> + if (errno != 0)
> + error ("Couldn't write debug register");
> +}
> +
> +/* Pass the address ADDR to the inferior in debug register REGNUM. */
> +
> +void
> +i386_dr_low_set_addr (int regnum, CORE_ADDR addr)
> +{
> + struct inferior_list_entry *lp;
> +
> + if (! (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR))
> + error ("Invalid debug register");
> +
> + for (lp = all_lwps.head; lp; lp = lp->next)
> + {
> + struct lwp_info *lwp = (struct lwp_info *) lp;
> + i386_linux_dr_set (ptid_of (lwp), DR_FIRSTADDR + regnum, addr);
> + }
> +}
> +
> +/* Pass the value VAL to the inferior in the DR7 debug control register. */
> +
> +void
> +i386_dr_low_set_control (unsigned control)
> +{
> + struct inferior_list_entry *lp;
> +
> + for (lp = all_lwps.head; lp; lp = lp->next)
> + {
> + struct lwp_info *lwp = (struct lwp_info *) lp;
> + i386_linux_dr_set (ptid_of (lwp), DR_CONTROL, control);
> + }
> +}
> +
> +/* Get the value of the DR6 debug status register from the inferior. */
> +
> +unsigned
> +i386_dr_low_get_status (void)
> +{
> + ptid_t inferior_ptid = ptid_of (get_thread_lwp (current_inferior));
> + return i386_linux_dr_get (inferior_ptid, DR_STATUS);
> +}
> +
> +/* Watchpoint support. */
> +
> +static int
> +i386_insert_watchpoint (struct arch_process_info *arch_private,
> + char type, CORE_ADDR addr, int len)
> +{
> + return i386_low_insert_watchpoint (&arch_private->debug_reg_state,
> + type, addr, len);
> +}
> +
> +static int
> +i386_remove_watchpoint (struct arch_process_info *arch_private,
> + char type, CORE_ADDR addr, int len)
> +{
> + return i386_low_remove_watchpoint (&arch_private->debug_reg_state,
> + type, addr, len);
> +}
> +
> +static int
> +i386_stopped_by_watchpoint (struct arch_process_info *arch_private)
> +{
> + return i386_low_stopped_by_watchpoint (&arch_private->debug_reg_state);
> +}
> +
> +static CORE_ADDR
> +i386_stopped_data_address (struct arch_process_info *arch_private)
> +{
> + return i386_low_stopped_data_address (&arch_private->debug_reg_state);
> +}
> +
> +/* Called when a new process is created. */
> +
> +struct arch_process_info *
> +i386_linux_new_process (int pid, int attached)
> +{
> + struct arch_process_info *info = xcalloc (1, sizeof (*info));
> +
> + return info;
> +}
> +
> +/* Called when a new thread is detected.
> + INITIAL is non-zero for the main thread, zero otherwise. */
> +
> +static void
> +i386_linux_new_thread (struct lwp_info *lwp, int initial)
> +{
> + /* The initial thread has debug regs set later during process
> + creation/attaching handling. */
> +
> + if (! initial)
> + {
> + int i;
> + ptid_t ptid = ptid_of (lwp);
> + int pid = PIDGET (ptid);
> + struct process_info *proc = find_process_pid (pid);
> + struct arch_process_info *arch_private = proc->private->arch_private;
> + struct i386_debug_reg_state *state = &arch_private->debug_reg_state;
> +
> + for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
> + i386_linux_dr_set (ptid, i, state->dr_mirror[i]);
> +
> + i386_linux_dr_set (ptid, DR_CONTROL, state->dr_control_mirror);
> + }
> +}
>
> struct linux_target_ops the_low_target = {
> init_registers_i386_linux,
> @@ -201,10 +349,12 @@ struct linux_target_ops the_low_target =
> NULL,
> 1,
> i386_breakpoint_at,
> + i386_insert_watchpoint,
> + i386_remove_watchpoint,
> + i386_stopped_by_watchpoint,
> + i386_stopped_data_address,
> NULL,
> NULL,
> - NULL,
> - NULL,
> - NULL,
> - NULL,
> + i386_linux_new_process,
> + i386_linux_new_thread
> };
> Index: linux-low.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/linux-low.c,v
> retrieving revision 1.97
> diff -u -p -r1.97 linux-low.c
> --- linux-low.c 3 Apr 2009 11:40:02 -0000 1.97
> +++ linux-low.c 30 Apr 2009 06:26:54 -0000
> @@ -120,6 +120,7 @@ static int must_set_ptrace_flags;
> control of gdbserver have the same architecture. */
> static int new_inferior;
>
> +static void notify_low_target_new_thread (struct lwp_info *lwp, int initial);
> static void linux_resume_one_lwp (struct inferior_list_entry *entry,
> int step, int signal, siginfo_t *info);
> static void linux_resume (struct thread_resume *resume_info, size_t n);
> @@ -179,6 +180,9 @@ linux_add_process (int pid, int attached
> proc = add_process (pid, attached);
> proc->private = xcalloc (1, sizeof (*proc->private));
>
> + if (the_low_target.new_process != NULL)
> + proc->private->arch_private = the_low_target.new_process (pid, attached);
> +
> return proc;
> }
>
> @@ -188,6 +192,7 @@ linux_add_process (int pid, int attached
> static void
> linux_remove_process (struct process_info *process)
> {
> + free (process->private->arch_private);
> free (process->private);
> remove_process (process);
> }
> @@ -231,6 +236,7 @@ handle_extended_wait (struct lwp_info *e
> ptid = ptid_build (pid_of (event_child), new_pid, 0);
> new_lwp = (struct lwp_info *) add_lwp (ptid);
> add_thread (ptid, new_lwp);
> + notify_low_target_new_thread (new_lwp, 0);
>
> /* Normally we will get the pending SIGSTOP. But in some cases
> we might get another signal delivered to the group first.
> @@ -313,6 +319,18 @@ add_lwp (ptid_t ptid)
> return lwp;
> }
>
> +/* Notify the backend that we have a new thread, be it the main thread
> + or a later one.
> + INITIAL is non-zero for the main thread, zero otherwise.
> + NOTE: This must be called when the thread is stopped. */
> +
> +static void
> +notify_low_target_new_thread (struct lwp_info *lwp, int initial)
> +{
> + if (the_low_target.new_thread != NULL)
> + the_low_target.new_thread (lwp, initial);
> +}
> +
> /* Start an inferior process and returns its pid.
> ALLARGS is a vector of program-name and args. */
>
> @@ -354,6 +372,8 @@ linux_create_inferior (char *program, ch
> ptid = ptid_build (pid, pid, 0);
> new_lwp = add_lwp (ptid);
> add_thread (ptid, new_lwp);
> + /* We can't call notify_low_target_new_thread there, the thread isn't
> + stopped. Piggyback on must_set_ptrace_flags and call it then. */
> must_set_ptrace_flags = 1;
>
> return pid;
> @@ -401,6 +421,7 @@ linux_attach_lwp_1 (unsigned long lwpid,
>
> new_lwp = (struct lwp_info *) add_lwp (ptid);
> add_thread (ptid, new_lwp);
> + notify_low_target_new_thread (new_lwp, initial);
>
> /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
> brings it to a halt.
> @@ -1261,6 +1282,7 @@ retry:
> if (must_set_ptrace_flags)
> {
> ptrace (PTRACE_SETOPTIONS, lwpid_of (lwp), 0, PTRACE_O_TRACECLONE);
> + notify_low_target_new_thread (lwp, 1);
> must_set_ptrace_flags = 0;
> }
> /* If we are waiting for a particular child, and it exited,
> @@ -2599,7 +2623,11 @@ static int
> linux_insert_watchpoint (char type, CORE_ADDR addr, int len)
> {
> if (the_low_target.insert_watchpoint != NULL)
> - return the_low_target.insert_watchpoint (type, addr, len);
> + {
> + struct process_info *proc = current_process ();
> + return the_low_target.insert_watchpoint (proc->private->arch_private,
> + type, addr, len);
> + }
> else
> /* Unsupported (see target.h). */
> return 1;
> @@ -2609,7 +2637,11 @@ static int
> linux_remove_watchpoint (char type, CORE_ADDR addr, int len)
> {
> if (the_low_target.remove_watchpoint != NULL)
> - return the_low_target.remove_watchpoint (type, addr, len);
> + {
> + struct process_info *proc = current_process ();
> + return the_low_target.remove_watchpoint (proc->private->arch_private,
> + type, addr, len);
> + }
> else
> /* Unsupported (see target.h). */
> return 1;
> @@ -2619,7 +2651,10 @@ static int
> linux_stopped_by_watchpoint (void)
> {
> if (the_low_target.stopped_by_watchpoint != NULL)
> - return the_low_target.stopped_by_watchpoint ();
> + {
> + struct process_info *proc = current_process ();
> + return the_low_target.stopped_by_watchpoint (proc->private->arch_private);
> + }
> else
> return 0;
> }
> @@ -2628,7 +2663,10 @@ static CORE_ADDR
> linux_stopped_data_address (void)
> {
> if (the_low_target.stopped_data_address != NULL)
> - return the_low_target.stopped_data_address ();
> + {
> + struct process_info *proc = current_process ();
> + return the_low_target.stopped_data_address (proc->private->arch_private);
> + }
> else
> return 0;
> }
> Index: linux-low.h
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/linux-low.h,v
> retrieving revision 1.28
> diff -u -p -r1.28 linux-low.h
> --- linux-low.h 1 Apr 2009 22:50:24 -0000 1.28
> +++ linux-low.h 30 Apr 2009 01:23:29 -0000
> @@ -54,8 +54,13 @@ struct process_info_private
>
> /* Connection to the libthread_db library. */
> td_thragent_t *thread_agent;
> +
> + /* Target-specific additions. */
> + struct arch_process_info *arch_private;
> };
>
> +struct lwp_info;
> +
> struct linux_target_ops
> {
> /* Architecture-specific setup. */
> @@ -75,26 +80,37 @@ struct linux_target_ops
> int breakpoint_len;
> CORE_ADDR (*breakpoint_reinsert_addr) (void);
>
> -
> int decr_pc_after_break;
> int (*breakpoint_at) (CORE_ADDR pc);
>
> /* Watchpoint related functions. See target.h for comments. */
> - int (*insert_watchpoint) (char type, CORE_ADDR addr, int len);
> - int (*remove_watchpoint) (char type, CORE_ADDR addr, int len);
> - int (*stopped_by_watchpoint) (void);
> - CORE_ADDR (*stopped_data_address) (void);
> + int (*insert_watchpoint) (struct arch_process_info *arch_private,
> + char type, CORE_ADDR addr, int len);
> + int (*remove_watchpoint) (struct arch_process_info *arch_private,
> + char type, CORE_ADDR addr, int len);
> + int (*stopped_by_watchpoint) (struct arch_process_info *arch_private);
> + CORE_ADDR (*stopped_data_address) (struct arch_process_info *arch_private);
>
> /* Hooks to reformat register data for PEEKUSR/POKEUSR (in particular
> for registers smaller than an xfer unit). */
> void (*collect_ptrace_register) (int regno, char *buf);
> void (*supply_ptrace_register) (int regno, const char *buf);
> +
> + /* Hook to call when a new process is created or attached to. */
> + struct arch_process_info * (*new_process) (int pid, int attached);
> +
> + /* Hook to call when a new thread is detected.
> + INITIAL is non-zero for the main thread, zero otherwise. */
> + void (*new_thread) (struct lwp_info *, int initial);
> };
>
> extern struct linux_target_ops the_low_target;
>
> +#define ptid_of(proc) ((proc)->head.id)
> #define pid_of(proc) ptid_get_pid ((proc)->head.id)
> #define lwpid_of(proc) ptid_get_lwp ((proc)->head.id)
> +#define PIDGET(ptid) ptid_get_pid (ptid)
> +#define TIDGET(ptid) ptid_get_lwp (ptid)
>
> #define get_lwp(inf) ((struct lwp_info *)(inf))
> #define get_thread_lwp(thr) (get_lwp (inferior_target_data (thr)))
> Index: linux-x86-64-low.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/linux-x86-64-low.c,v
> retrieving revision 1.22
> diff -u -p -r1.22 linux-x86-64-low.c
> --- linux-x86-64-low.c 22 Mar 2009 23:57:10 -0000 1.22
> +++ linux-x86-64-low.c 30 Apr 2009 01:23:29 -0000
> @@ -18,9 +18,11 @@
> You should have received a copy of the GNU General Public License
> along with this program. If not, see <http://www.gnu.org/licenses/>. */
>
> +#include <stddef.h>
> #include "server.h"
> #include "linux-low.h"
> #include "i387-fp.h"
> +#include "i386-low.h"
>
> #include "gdb_proc_service.h"
>
> @@ -45,6 +47,11 @@ void init_registers_x86_64_linux (void);
> #define ARCH_GET_GS 0x1004
> #endif
>
> +struct arch_process_info
> +{
> + struct i386_debug_reg_state debug_reg_state;
> +};
> +
> static int x86_64_regmap[] = {
> RAX * 8, RBX * 8, RCX * 8, RDX * 8,
> RSI * 8, RDI * 8, RBP * 8, RSP * 8,
> @@ -161,6 +168,148 @@ x86_64_breakpoint_at (CORE_ADDR pc)
>
> return 0;
> }
> +
> +/* Support for debug registers. */
> +
> +static unsigned long
> +x86_64_linux_dr_get (ptid_t ptid, int regnum)
> +{
> + int tid;
> + unsigned long value;
> +
> + tid = TIDGET (ptid);
> + if (tid == 0)
> + tid = PIDGET (ptid);
> +
> + errno = 0;
> + value = ptrace (PTRACE_PEEKUSER, tid,
> + offsetof (struct user, u_debugreg[regnum]), 0);
> + if (errno != 0)
> + error ("Couldn't read debug register");
> +
> + return value;
> +}
> +
> +static void
> +x86_64_linux_dr_set (ptid_t ptid, int regnum, unsigned long value)
> +{
> + int tid;
> +
> + tid = TIDGET (ptid);
> + if (tid == 0)
> + tid = PIDGET (ptid);
> +
> + errno = 0;
> + ptrace (PTRACE_POKEUSER, tid,
> + offsetof (struct user, u_debugreg[regnum]), value);
> + if (errno != 0)
> + error ("Couldn't write debug register");
> +}
> +
> +/* Pass the address ADDR to the inferior in debug register REGNUM. */
> +
> +void
> +i386_dr_low_set_addr (int regnum, CORE_ADDR addr)
> +{
> + struct inferior_list_entry *lp;
> +
> + if (! (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR))
> + error ("Invalid debug register");
> +
> + for (lp = all_lwps.head; lp; lp = lp->next)
> + {
> + struct lwp_info *lwp = (struct lwp_info *) lp;
> + x86_64_linux_dr_set (ptid_of (lwp), DR_FIRSTADDR + regnum, addr);
> + }
> +}
> +
> +/* Pass the value VAL to the inferior in the DR7 debug control register. */
> +
> +void
> +i386_dr_low_set_control (unsigned control)
> +{
> + struct inferior_list_entry *lp;
> +
> + for (lp = all_lwps.head; lp; lp = lp->next)
> + {
> + struct lwp_info *lwp = (struct lwp_info *) lp;
> + x86_64_linux_dr_set (ptid_of (lwp), DR_CONTROL, control);
> + }
> +}
> +
> +/* Get the value of the DR6 debug status register from the inferior. */
> +
> +unsigned
> +i386_dr_low_get_status (void)
> +{
> + ptid_t inferior_ptid = ptid_of (get_thread_lwp (current_inferior));
> + return x86_64_linux_dr_get (inferior_ptid, DR_STATUS);
> +}
> +
> +/* Watchpoint support. */
> +
> +static int
> +x86_64_insert_watchpoint (struct arch_process_info *arch_private,
> + char type, CORE_ADDR addr, int len)
> +{
> + return i386_low_insert_watchpoint (&arch_private->debug_reg_state,
> + type, addr, len);
> +}
> +
> +static int
> +x86_64_remove_watchpoint (struct arch_process_info *arch_private,
> + char type, CORE_ADDR addr, int len)
> +{
> + return i386_low_remove_watchpoint (&arch_private->debug_reg_state,
> + type, addr, len);
> +}
> +
> +static int
> +x86_64_stopped_by_watchpoint (struct arch_process_info *arch_private)
> +{
> + return i386_low_stopped_by_watchpoint (&arch_private->debug_reg_state);
> +}
> +
> +static CORE_ADDR
> +x86_64_stopped_data_address (struct arch_process_info *arch_private)
> +{
> + return i386_low_stopped_data_address (&arch_private->debug_reg_state);
> +}
> +
> +/* Called when a new process is created. */
> +
> +struct arch_process_info *
> +x86_64_linux_new_process (int pid, int attached)
> +{
> + struct arch_process_info *info = xcalloc (1, sizeof (*info));
> +
> + return info;
> +}
> +
> +/* Called when a new thread is detected.
> + INITIAL is non-zero for the main thread, zero otherwise. */
> +
> +static void
> +x86_64_linux_new_thread (struct lwp_info *lwp, int initial)
> +{
> + /* The initial thread has debug regs set later during process
> + creation/attaching handling. */
> +
> + if (! initial)
> + {
> + int i;
> + ptid_t ptid = ptid_of (lwp);
> + int pid = PIDGET (ptid);
> + struct process_info *proc = find_process_pid (pid);
> + struct arch_process_info *arch_private = proc->private->arch_private;
> + struct i386_debug_reg_state *state = &arch_private->debug_reg_state;
> +
> + for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
> + x86_64_linux_dr_set (ptid, i, state->dr_mirror[i]);
> +
> + x86_64_linux_dr_set (ptid, DR_CONTROL, state->dr_control_mirror);
> + }
> +}
>
> struct linux_target_ops the_low_target = {
> init_registers_x86_64_linux,
> @@ -175,10 +324,12 @@ struct linux_target_ops the_low_target =
> NULL,
> 1,
> x86_64_breakpoint_at,
> + x86_64_insert_watchpoint,
> + x86_64_remove_watchpoint,
> + x86_64_stopped_by_watchpoint,
> + x86_64_stopped_data_address,
> NULL,
> NULL,
> - NULL,
> - NULL,
> - NULL,
> - NULL,
> + x86_64_linux_new_process,
> + x86_64_linux_new_thread
> };
> Index: server.h
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/server.h,v
> retrieving revision 1.56
> diff -u -p -r1.56 server.h
> --- server.h 3 Apr 2009 20:15:51 -0000 1.56
> +++ server.h 30 Apr 2009 01:23:29 -0000
> @@ -405,6 +405,7 @@ void perror_with_name (const char *strin
> void error (const char *string,...) ATTR_NORETURN ATTR_FORMAT (printf, 1, 2);
> void fatal (const char *string,...) ATTR_NORETURN ATTR_FORMAT (printf, 1, 2);
> void warning (const char *string,...) ATTR_FORMAT (printf, 1, 2);
> +char *paddr (CORE_ADDR addr);
>
> /* Maximum number of bytes to read/write at once. The value here
> is chosen to fill up a packet (the headers account for the 32). */
> Index: utils.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/utils.c,v
> retrieving revision 1.18
> diff -u -p -r1.18 utils.c
> --- utils.c 19 Jan 2009 00:16:46 -0000 1.18
> +++ utils.c 30 Apr 2009 01:23:29 -0000
> @@ -170,3 +170,37 @@ warning (const char *string,...)
> fprintf (stderr, "\n");
> va_end (args);
> }
> +
> +/* temporary storage using circular buffer */
> +#define NUMCELLS 4
> +#define CELLSIZE 50
> +static char *
> +get_cell (void)
> +{
> + static char buf[NUMCELLS][CELLSIZE];
> + static int cell = 0;
> + if (++cell >= NUMCELLS)
> + cell = 0;
> + return buf[cell];
> +}
> +
> +static int
> +xsnprintf (char *str, size_t size, const char *format, ...)
> +{
> + va_list args;
> + int ret;
> +
> + va_start (args, format);
> + ret = vsnprintf (str, size, format, args);
> + va_end (args);
> +
> + return ret;
> +}
> +
> +char *
> +paddr (CORE_ADDR addr)
> +{
> + char *str = get_cell ();
> + xsnprintf (str, CELLSIZE, "%lx", (long) addr);
> + return str;
> +}
> Index: win32-arm-low.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/win32-arm-low.c,v
> retrieving revision 1.8
> diff -u -p -r1.8 win32-arm-low.c
> --- win32-arm-low.c 3 Jan 2009 05:57:57 -0000 1.8
> +++ win32-arm-low.c 30 Apr 2009 01:23:29 -0000
> @@ -122,4 +122,9 @@ struct win32_target_ops the_low_target =
> NULL, /* single_step */
> (const unsigned char *) &arm_wince_breakpoint,
> arm_wince_breakpoint_len,
> + /* Watchpoint related functions. See target.h for comments. */
> + NULL, /* insert_watchpoint */
> + NULL, /* remove_watchpoint */
> + NULL, /* stopped_by_watchpoint */
> + NULL /* stopped_data_address */
> };
> Index: win32-i386-low.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/win32-i386-low.c,v
> retrieving revision 1.14
> diff -u -p -r1.14 win32-i386-low.c
> --- win32-i386-low.c 3 Jan 2009 05:57:57 -0000 1.14
> +++ win32-i386-low.c 30 Apr 2009 01:23:29 -0000
> @@ -17,6 +17,7 @@
>
> #include "server.h"
> #include "win32-low.h"
> +#include "i386-low.h"
>
> #define FCS_REGNUM 27
> #define FOP_REGNUM 31
> @@ -31,6 +32,42 @@ static unsigned dr[8];
> static int debug_registers_changed = 0;
> static int debug_registers_used = 0;
>
> +/* Pass the address ADDR to the inferior in the I'th debug register.
> + Here we just store the address in dr array, the registers will be
> + actually set up when windows_continue is called. */
> +
> +void
> +i386_dr_low_set_addr (int i, CORE_ADDR addr)
> +{
> + if (i < 0 || i > 3)
> + return;
> + dr[i] = (unsigned) addr;
> + debug_registers_changed = 1;
> + debug_registers_used = 1;
> +}
> +
> +/* Pass the value VAL to the inferior in the DR7 debug control register.
> + Here we just store the address in D_REGS, the watchpoint
> + will be actually set up in windows_wait. */
> +
> +void
> +i386_dr_low_set_control (unsigned val)
> +{
> + dr[7] = val;
> + debug_registers_changed = 1;
> + debug_registers_used = 1;
> +}
> +
> +/* Get the value of the DR6 debug status register from the inferior.
> + Here we just return the value stored in dr[6]
> + by the last call to thread_rec for current_event.dwThreadId id. */
> +
> +unsigned
> +i386_dr_low_get_status (void)
> +{
> + return dr[6];
> +}
> +
> static void
> i386_initial_stuff (void)
> {
> @@ -205,4 +242,8 @@ struct win32_target_ops the_low_target =
> i386_single_step,
> NULL, /* breakpoint */
> 0, /* breakpoint_len */
> + i386_insert_watchpoint,
> + i386_remove_watchpoint,
> + i386_stopped_by_watchpoint,
> + i386_stopped_data_address
> };
> Index: win32-low.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/win32-low.c,v
> retrieving revision 1.35
> diff -u -p -r1.35 win32-low.c
> --- win32-low.c 1 Apr 2009 22:50:24 -0000 1.35
> +++ win32-low.c 30 Apr 2009 01:23:29 -0000
> @@ -228,6 +228,48 @@ child_delete_thread (DWORD pid, DWORD ti
> delete_thread_info (thread);
> }
>
> +/* These watchpoint related wrapper functions simply pass on the function call
> + if the target has registered a corresponding function. */
> +
> +static int
> +win32_insert_watchpoint (char type, CORE_ADDR addr, int len)
> +{
> + if (the_low_target.insert_watchpoint != NULL)
> + return the_low_target.insert_watchpoint (type, addr, len);
> + else
> + /* Unsupported (see target.h). */
> + return 1;
> +}
> +
> +static int
> +win32_remove_watchpoint (char type, CORE_ADDR addr, int len)
> +{
> + if (the_low_target.remove_watchpoint != NULL)
> + return the_low_target.remove_watchpoint (type, addr, len);
> + else
> + /* Unsupported (see target.h). */
> + return 1;
> +}
> +
> +static int
> +win32_stopped_by_watchpoint (void)
> +{
> + if (the_low_target.stopped_by_watchpoint != NULL)
> + return the_low_target.stopped_by_watchpoint ();
> + else
> + return 0;
> +}
> +
> +static CORE_ADDR
> +win32_stopped_data_address (void)
> +{
> + if (the_low_target.stopped_data_address != NULL)
> + return the_low_target.stopped_data_address ();
> + else
> + return 0;
> +}
> +
> +
> /* Transfer memory from/to the debugged process. */
> static int
> child_xfer_memory (CORE_ADDR memaddr, char *our, int len,
> @@ -1697,10 +1739,10 @@ static struct target_ops win32_target_op
> NULL,
> win32_request_interrupt,
> NULL,
> - NULL,
> - NULL,
> - NULL,
> - NULL,
> + win32_insert_watchpoint,
> + win32_remove_watchpoint,
> + win32_stopped_by_watchpoint,
> + win32_stopped_data_address,
> NULL,
> NULL,
> NULL,
> Index: win32-low.h
> ===================================================================
> RCS file: /cvs/src/src/gdb/gdbserver/win32-low.h,v
> retrieving revision 1.9
> diff -u -p -r1.9 win32-low.h
> --- win32-low.h 3 Jan 2009 05:57:57 -0000 1.9
> +++ win32-low.h 30 Apr 2009 01:23:29 -0000
> @@ -70,6 +70,13 @@ struct win32_target_ops
>
> const unsigned char *breakpoint;
> int breakpoint_len;
> +
> + /* Watchpoint related functions. See target.h for comments. */
> + int (*insert_watchpoint) (char type, CORE_ADDR addr, int len);
> + int (*remove_watchpoint) (char type, CORE_ADDR addr, int len);
> + int (*stopped_by_watchpoint) (void);
> + CORE_ADDR (*stopped_data_address) (void);
> +
> };
>
> extern struct win32_target_ops the_low_target;
>
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