diff options
| -rw-r--r-- | gdb/ChangeLog | 47 | ||||
| -rw-r--r-- | gdb/Makefile.in | 3 | ||||
| -rw-r--r-- | gdb/breakpoint.c | 3 | ||||
| -rwxr-xr-x | gdb/configure | 2 | ||||
| -rw-r--r-- | gdb/configure.ac | 2 | ||||
| -rw-r--r-- | gdb/dtrace-probe.c | 907 |
6 files changed, 960 insertions, 4 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index c14b708..4cc7b77 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,50 @@ +2015-01-17 Jose E. Marchesi <jose.marchesi@oracle.com> + + * breakpoint.c (BREAK_ARGS_HELP): Help string updated to mention + the -probe-dtrace new vpossible value for PROBE_MODIFIER. + * configure.ac (CONFIG_OBS): dtrace-probe.o added if BFD can + handle ELF files. + * Makefile.in (SFILES): dtrace-probe.c added. + * configure: Regenerate. + * dtrace-probe.c: New file. + (SHT_SUNW_dof): New constant. + (dtrace_probe_type): New enum. + (dtrace_probe_arg): New struct. + (dtrace_probe_arg_s): New typedef. + (struct dtrace_probe_enabler): New struct. + (dtrace_probe_enabler_s): New typedef. + (dtrace_probe): New struct. + (dtrace_probe_is_linespec): New function. + (dtrace_dof_sect_type): New enum. + (dtrace_dof_dofh_ident): Likewise. + (dtrace_dof_encoding): Likewise. + (DTRACE_DOF_ENCODE_LSB): Likewise. + (DTRACE_DOF_ENCODE_MSB): Likewise. + (dtrace_dof_hdr): New struct. + (dtrace_dof_sect): Likewise. + (dtrace_dof_provider): Likewise. + (dtrace_dof_probe): Likewise. + (DOF_UINT): New macro. + (DTRACE_DOF_PTR): Likewise. + (DTRACE_DOF_SECT): Likewise. + (dtrace_process_dof_probe): New function. + (dtrace_process_dof): Likewise. + (dtrace_build_arg_exprs): Likewise. + (dtrace_get_arg): Likewise. + (dtrace_get_probes): Likewise. + (dtrace_get_probe_argument_count): Likewise. + (dtrace_can_evaluate_probe_arguments): Likewise. + (dtrace_evaluate_probe_argument): Likewise. + (dtrace_compile_to_ax): Likewise. + (dtrace_probe_destroy): Likewise. + (dtrace_gen_info_probes_table_header): Likewise. + (dtrace_gen_info_probes_table_values): Likewise. + (dtrace_probe_is_enabled): Likewise. + (dtrace_probe_ops): New variable. + (info_probes_dtrace_command): New function. + (_initialize_dtrace_probe): Likewise. + (dtrace_type_name): Likewise. + 2015-02-17 Jose E. Marchesi <jose.marchesi@oracle.com> * gdbarch.sh (dtrace_parse_probe_argument): New. diff --git a/gdb/Makefile.in b/gdb/Makefile.in index 00fb2cd..c646ee5 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -820,7 +820,8 @@ SFILES = ada-exp.y ada-lang.c ada-typeprint.c ada-valprint.c ada-tasks.c \ cp-abi.c cp-support.c cp-namespace.c cp-valprint.c \ d-exp.y d-lang.c d-valprint.c \ cp-name-parser.y \ - dbxread.c demangle.c dictionary.c disasm.c doublest.c dummy-frame.c \ + dbxread.c demangle.c dictionary.c disasm.c doublest.c \ + dtrace-probe.c dummy-frame.c \ dwarf2expr.c dwarf2loc.c dwarf2read.c dwarf2-frame.c \ dwarf2-frame-tailcall.c \ elfread.c environ.c eval.c event-loop.c event-top.c \ diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c index a7cc6cb..db4b872 100644 --- a/gdb/breakpoint.c +++ b/gdb/breakpoint.c @@ -15976,7 +15976,8 @@ all_tracepoints (void) command" [PROBE_MODIFIER] [LOCATION] [thread THREADNUM] [if CONDITION]\n\ PROBE_MODIFIER shall be present if the command is to be placed in a\n\ probe point. Accepted values are `-probe' (for a generic, automatically\n\ -guessed probe type) or `-probe-stap' (for a SystemTap probe).\n\ +guessed probe type), `-probe-stap' (for a SystemTap probe) or \n\ +`-probe-dtrace' (for a DTrace probe).\n\ LOCATION may be a line number, function name, or \"*\" and an address.\n\ If a line number is specified, break at start of code for that line.\n\ If a function is specified, break at start of code for that function.\n\ diff --git a/gdb/configure b/gdb/configure index 9632f9a..30a54d2 100755 --- a/gdb/configure +++ b/gdb/configure @@ -13068,7 +13068,7 @@ $as_echo "$gdb_cv_var_elf" >&6; } LDFLAGS=$OLD_LDFLAGS LIBS=$OLD_LIBS if test $gdb_cv_var_elf = yes; then - CONFIG_OBS="$CONFIG_OBS elfread.o stap-probe.o" + CONFIG_OBS="$CONFIG_OBS elfread.o stap-probe.o dtrace-probe.o" $as_echo "#define HAVE_ELF 1" >>confdefs.h diff --git a/gdb/configure.ac b/gdb/configure.ac index dfc6947..39fcef2 100644 --- a/gdb/configure.ac +++ b/gdb/configure.ac @@ -2074,7 +2074,7 @@ AC_SUBST(WIN32LIBS) GDB_AC_CHECK_BFD([for ELF support in BFD], gdb_cv_var_elf, [bfd_get_elf_phdr_upper_bound (NULL)], elf-bfd.h) if test $gdb_cv_var_elf = yes; then - CONFIG_OBS="$CONFIG_OBS elfread.o stap-probe.o" + CONFIG_OBS="$CONFIG_OBS elfread.o stap-probe.o dtrace-probe.o" AC_DEFINE(HAVE_ELF, 1, [Define if ELF support should be included.]) # -ldl is provided by bfd/Makfile.am (LIBDL) <PLUGINS>. diff --git a/gdb/dtrace-probe.c b/gdb/dtrace-probe.c new file mode 100644 index 0000000..a6544ba --- /dev/null +++ b/gdb/dtrace-probe.c @@ -0,0 +1,907 @@ +/* DTrace probe support for GDB. + + Copyright (C) 2014-2015 Free Software Foundation, Inc. + + Contributed by Oracle, 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 "defs.h" +#include "probe.h" +#include "vec.h" +#include "elf-bfd.h" +#include "gdbtypes.h" +#include "obstack.h" +#include "objfiles.h" +#include "complaints.h" +#include "value.h" +#include "ax.h" +#include "ax-gdb.h" +#include "language.h" +#include "parser-defs.h" +#include "inferior.h" + +/* The type of the ELF sections where we will find the DOF programs + with information about probes. */ + +#ifndef SHT_SUNW_dof +# define SHT_SUNW_dof 0x6ffffff4 +#endif + +/* Forward declaration. */ + +static const struct probe_ops dtrace_probe_ops; + +/* The following structure represents a single argument for the + probe. */ + +struct dtrace_probe_arg +{ + /* The type of the probe argument. */ + struct type *type; + + /* A string describing the type. */ + char *type_str; + + /* The argument converted to an internal GDB expression. */ + struct expression *expr; +}; + +typedef struct dtrace_probe_arg dtrace_probe_arg_s; +DEF_VEC_O (dtrace_probe_arg_s); + +/* The following structure represents an enabler for a probe. */ + +struct dtrace_probe_enabler +{ + /* Program counter where the is-enabled probe is installed. The + contents (nops, whatever...) stored at this address are + architecture dependent. */ + CORE_ADDR address; +}; + +typedef struct dtrace_probe_enabler dtrace_probe_enabler_s; +DEF_VEC_O (dtrace_probe_enabler_s); + +/* The following structure represents a dtrace probe. */ + +struct dtrace_probe +{ + /* Generic information about the probe. This must be the first + element of this struct, in order to maintain binary compatibility + with the `struct probe' and be able to fully abstract it. */ + struct probe p; + + /* A probe can have zero or more arguments. */ + int probe_argc; + VEC (dtrace_probe_arg_s) *args; + + /* A probe can have zero or more "enablers" associated with it. */ + VEC (dtrace_probe_enabler_s) *enablers; + + /* Whether the expressions for the arguments have been built. */ + unsigned int args_expr_built : 1; +}; + +/* Implementation of the probe_is_linespec method. */ + +static int +dtrace_probe_is_linespec (const char **linespecp) +{ + static const char *const keywords[] = { "-pdtrace", "-probe-dtrace", NULL }; + + return probe_is_linespec_by_keyword (linespecp, keywords); +} + +/* DOF programs can contain an arbitrary number of sections of 26 + different types. In order to support DTrace USDT probes we only + need to handle a subset of these section types, fortunately. These + section types are defined in the following enumeration. + + See linux/dtrace/dof_defines.h for a complete list of section types + along with their values. */ + +enum dtrace_dof_sect_type +{ + /* Null section. */ + DTRACE_DOF_SECT_TYPE_NONE = 0, + /* A dof_ecbdesc_t. */ + DTRACE_DOF_SECT_TYPE_ECBDESC = 3, + /* A string table. */ + DTRACE_DOF_SECT_TYPE_STRTAB = 8, + /* A dof_provider_t */ + DTRACE_DOF_SECT_TYPE_PROVIDER = 15, + /* Array of dof_probe_t */ + DTRACE_DOF_SECT_TYPE_PROBES = 16, + /* An array of probe arg mappings. */ + DTRACE_DOF_SECT_TYPE_PRARGS = 17, + /* An array of probe arg offsets. */ + DTRACE_DOF_SECT_TYPE_PROFFS = 18, + /* An array of probe is-enabled offsets. */ + DTRACE_DOF_SECT_TYPE_PRENOFFS = 26 +}; + +/* The following collection of data structures map the structure of + DOF entities. Again, we only cover the subset of DOF used to + implement USDT probes. + + See linux/dtrace/dof.h header for a complete list of data + structures. */ + +/* Offsets to index the dofh_ident[] array defined below. */ + +enum dtrace_dof_ident +{ + /* First byte of the magic number. */ + DTRACE_DOF_ID_MAG0 = 0, + /* Second byte of the magic number. */ + DTRACE_DOF_ID_MAG1 = 1, + /* Third byte of the magic number. */ + DTRACE_DOF_ID_MAG2 = 2, + /* Fourth byte of the magic number. */ + DTRACE_DOF_ID_MAG3 = 3, + /* An enum_dof_encoding value. */ + DTRACE_DOF_ID_ENCODING = 5 +}; + +/* Possible values for dofh_ident[DOF_ID_ENCODING]. */ + +enum dtrace_dof_encoding +{ + /* The DOF program is little-endian. */ + DTRACE_DOF_ENCODE_LSB = 1, + /* The DOF program is big-endian. */ + DTRACE_DOF_ENCODE_MSB = 2 +}; + +/* A DOF header, which describes the contents of a DOF program: number + of sections, size, etc. */ + +struct dtrace_dof_hdr +{ + /* Identification bytes (see above). */ + uint8_t dofh_ident[16]; + /* File attribute flags (if any). */ + uint32_t dofh_flags; + /* Size of file header in bytes. */ + uint32_t dofh_hdrsize; + /* Size of section header in bytes. */ + uint32_t dofh_secsize; + /* Number of section headers. */ + uint32_t dofh_secnum; + /* File offset of section headers. */ + uint64_t dofh_secoff; + /* File size of loadable portion. */ + uint64_t dofh_loadsz; + /* File size of entire DOF file. */ + uint64_t dofh_filesz; + /* Reserved for future use. */ + uint64_t dofh_pad; +}; + +/* A DOF section, whose contents depend on its type. The several + supported section types are described in the enum + dtrace_dof_sect_type above. */ + +struct dtrace_dof_sect +{ + /* Section type (see the define above). */ + uint32_t dofs_type; + /* Section data memory alignment. */ + uint32_t dofs_align; + /* Section flags (if any). */ + uint32_t dofs_flags; + /* Size of section entry (if table). */ + uint32_t dofs_entsize; + /* DOF + offset points to the section data. */ + uint64_t dofs_offset; + /* Size of section data in bytes. */ + uint64_t dofs_size; +}; + +/* A DOF provider, which is the provider of a probe. */ + +struct dtrace_dof_provider +{ + /* Link to a DTRACE_DOF_SECT_TYPE_STRTAB section. */ + uint32_t dofpv_strtab; + /* Link to a DTRACE_DOF_SECT_TYPE_PROBES section. */ + uint32_t dofpv_probes; + /* Link to a DTRACE_DOF_SECT_TYPE_PRARGS section. */ + uint32_t dofpv_prargs; + /* Link to a DTRACE_DOF_SECT_TYPE_PROFFS section. */ + uint32_t dofpv_proffs; + /* Provider name string. */ + uint32_t dofpv_name; + /* Provider attributes. */ + uint32_t dofpv_provattr; + /* Module attributes. */ + uint32_t dofpv_modattr; + /* Function attributes. */ + uint32_t dofpv_funcattr; + /* Name attributes. */ + uint32_t dofpv_nameattr; + /* Args attributes. */ + uint32_t dofpv_argsattr; + /* Link to a DTRACE_DOF_SECT_PRENOFFS section. */ + uint32_t dofpv_prenoffs; +}; + +/* A set of DOF probes and is-enabled probes sharing a base address + and several attributes. The particular locations and attributes of + each probe are maintained in arrays in several other DOF sections. + See the comment in dtrace_process_dof_probe for details on how + these attributes are stored. */ + +struct dtrace_dof_probe +{ + /* Probe base address or offset. */ + uint64_t dofpr_addr; + /* Probe function string. */ + uint32_t dofpr_func; + /* Probe name string. */ + uint32_t dofpr_name; + /* Native argument type strings. */ + uint32_t dofpr_nargv; + /* Translated argument type strings. */ + uint32_t dofpr_xargv; + /* Index of first argument mapping. */ + uint32_t dofpr_argidx; + /* Index of first offset entry. */ + uint32_t dofpr_offidx; + /* Native argument count. */ + uint8_t dofpr_nargc; + /* Translated argument count. */ + uint8_t dofpr_xargc; + /* Number of offset entries for probe. */ + uint16_t dofpr_noffs; + /* Index of first is-enabled offset. */ + uint32_t dofpr_enoffidx; + /* Number of is-enabled offsets. */ + uint16_t dofpr_nenoffs; + /* Reserved for future use. */ + uint16_t dofpr_pad1; + /* Reserved for future use. */ + uint32_t dofpr_pad2; +}; + +/* DOF supports two different encodings: MSB (big-endian) and LSB + (little-endian). The encoding is itself encoded in the DOF header. + The following function returns an unsigned value in the host + endianness. */ + +#define DOF_UINT(dof, field) \ + extract_unsigned_integer ((gdb_byte *) &(field), \ + sizeof ((field)), \ + (((dof)->dofh_ident[DTRACE_DOF_ID_ENCODING] \ + == DTRACE_DOF_ENCODE_MSB) \ + ? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE)) + +/* The following macro applies a given byte offset to a DOF (a pointer + to a dtrace_dof_hdr structure) and returns the resulting + address. */ + +#define DTRACE_DOF_PTR(dof, offset) (&((char *) (dof))[(offset)]) + +/* The following macro returns a pointer to the beginning of a given + section in a DOF object. The section is referred to by its index + in the sections array. */ + +#define DTRACE_DOF_SECT(dof, idx) \ + ((struct dtrace_dof_sect *) \ + DTRACE_DOF_PTR ((dof), \ + DOF_UINT ((dof), (dof)->dofh_secoff) \ + + ((idx) * DOF_UINT ((dof), (dof)->dofh_secsize)))) + +/* Helper function to examine the probe described by the given PROBE + and PROVIDER data structures and add it to the PROBESP vector. + STRTAB, OFFTAB, EOFFTAB and ARGTAB are pointers to tables in the + DOF program containing the attributes for the probe. */ + +static void +dtrace_process_dof_probe (struct objfile *objfile, + struct gdbarch *gdbarch, VEC (probe_p) **probesp, + struct dtrace_dof_hdr *dof, + struct dtrace_dof_probe *probe, + struct dtrace_dof_provider *provider, + char *strtab, char *offtab, char *eofftab, + char *argtab, uint64_t strtab_size) +{ + int i, j, num_probes, num_enablers; + struct cleanup *cleanup; + VEC (dtrace_probe_enabler_s) *enablers; + char *p; + + /* Each probe section can define zero or more probes of two + different types: + + - probe->dofpr_noffs regular probes whose program counters are + stored in 32bit words starting at probe->dofpr_addr + + offtab[probe->dofpr_offidx]. + + - probe->dofpr_nenoffs is-enabled probes whose program counters + are stored in 32bit words starting at probe->dofpr_addr + + eofftab[probe->dofpr_enoffidx]. + + However is-enabled probes are not probes per-se, but an + optimization hack that is implemented in the kernel in a very + similar way than normal probes. This is how we support + is-enabled probes on GDB: + + - Our probes are always DTrace regular probes. + + - Our probes can be associated with zero or more "enablers". The + list of enablers is built from the is-enabled probes defined in + the Probe section. + + - Probes having a non-empty list of enablers can be enabled or + disabled using the `enable probe' and `disable probe' commands + respectively. The `Enabled' column in the output of `info + probes' will read `yes' if the enablers are activated, `no' + otherwise. + + - Probes having an empty list of enablers are always enabled. + The `Enabled' column in the output of `info probes' will + read `always'. + + It follows that if there are DTrace is-enabled probes defined for + some provider/name but no DTrace regular probes defined then the + GDB user wont be able to enable/disable these conditionals. */ + + num_probes = DOF_UINT (dof, probe->dofpr_noffs); + if (num_probes == 0) + return; + + /* Build the list of enablers for the probes defined in this Probe + DOF section. */ + enablers = NULL; + cleanup + = make_cleanup (VEC_cleanup (dtrace_probe_enabler_s), &enablers); + num_enablers = DOF_UINT (dof, probe->dofpr_nenoffs); + for (i = 0; i < num_enablers; i++) + { + struct dtrace_probe_enabler enabler; + uint32_t enabler_offset + = ((uint32_t *) eofftab)[DOF_UINT (dof, probe->dofpr_enoffidx) + i]; + + enabler.address = DOF_UINT (dof, probe->dofpr_addr) + + DOF_UINT (dof, enabler_offset); + VEC_safe_push (dtrace_probe_enabler_s, enablers, &enabler); + } + + for (i = 0; i < num_probes; i++) + { + uint32_t probe_offset + = ((uint32_t *) offtab)[DOF_UINT (dof, probe->dofpr_offidx) + i]; + struct dtrace_probe *ret + = obstack_alloc (&objfile->per_bfd->storage_obstack, sizeof (*ret)); + + ret->p.pops = &dtrace_probe_ops; + ret->p.arch = gdbarch; + ret->args_expr_built = 0; + + /* Set the provider and the name of the probe. */ + ret->p.provider + = xstrdup (strtab + DOF_UINT (dof, provider->dofpv_name)); + ret->p.name = xstrdup (strtab + DOF_UINT (dof, probe->dofpr_name)); + + /* The probe address. */ + ret->p.address + = DOF_UINT (dof, probe->dofpr_addr) + DOF_UINT (dof, probe_offset); + + /* Number of arguments in the probe. */ + ret->probe_argc = DOF_UINT (dof, probe->dofpr_nargc); + + /* Store argument type descriptions. A description of the type + of the argument is in the (J+1)th null-terminated string + starting at 'strtab' + 'probe->dofpr_nargv'. */ + ret->args = NULL; + p = strtab + DOF_UINT (dof, probe->dofpr_nargv); + for (j = 0; j < ret->probe_argc; j++) + { + struct dtrace_probe_arg arg; + struct expression *expr; + + arg.type_str = xstrdup (p); + + /* Use strtab_size as a sentinel. */ + while (*p++ != '\0' && p - strtab < strtab_size); + + /* Try to parse a type expression from the type string. If + this does not work then we set the type to `long + int'. */ + arg.type = builtin_type (gdbarch)->builtin_long; + expr = parse_expression (arg.type_str); + if (expr->elts[0].opcode == OP_TYPE) + arg.type = expr->elts[1].type; + + VEC_safe_push (dtrace_probe_arg_s, ret->args, &arg); + } + + /* Add the vector of enablers to this probe, if any. */ + ret->enablers = VEC_copy (dtrace_probe_enabler_s, enablers); + + /* Successfully created probe. */ + VEC_safe_push (probe_p, *probesp, (struct probe *) ret); + } + + do_cleanups (cleanup); +} + +/* Helper function to collect the probes described in the DOF program + whose header is pointed by DOF and add them to the PROBESP vector. + SECT is the ELF section containing the DOF program and OBJFILE is + its containing object file. */ + +static void +dtrace_process_dof (asection *sect, struct objfile *objfile, + VEC (probe_p) **probesp, struct dtrace_dof_hdr *dof) +{ + bfd *abfd = objfile->obfd; + int size = bfd_get_arch_size (abfd) / 8; + struct gdbarch *gdbarch = get_objfile_arch (objfile); + struct dtrace_dof_sect *section; + int i; + + /* The first step is to check for the DOF magic number. If no valid + DOF data is found in the section then a complaint is issued to + the user and the section skipped. */ + if (dof->dofh_ident[DTRACE_DOF_ID_MAG0] != 0x7F + || dof->dofh_ident[DTRACE_DOF_ID_MAG1] != 'D' + || dof->dofh_ident[DTRACE_DOF_ID_MAG2] != 'O' + || dof->dofh_ident[DTRACE_DOF_ID_MAG3] != 'F') + goto invalid_dof_data; + + /* Make sure the encoding mark is either DTRACE_DOF_ENCODE_LSB or + DTRACE_DOF_ENCODE_MSB. */ + if (dof->dofh_ident[DTRACE_DOF_ID_ENCODING] != DTRACE_DOF_ENCODE_LSB + && dof->dofh_ident[DTRACE_DOF_ID_ENCODING] != DTRACE_DOF_ENCODE_MSB) + goto invalid_dof_data; + + /* Make sure this DOF is not an enabling DOF, i.e. there are no ECB + Description sections. */ + section = (struct dtrace_dof_sect *) DTRACE_DOF_PTR (dof, + DOF_UINT (dof, dof->dofh_secoff)); + for (i = 0; i < DOF_UINT (dof, dof->dofh_secnum); i++, section++) + if (section->dofs_type == DTRACE_DOF_SECT_TYPE_ECBDESC) + return; + + /* Iterate over any section of type Provider and extract the probe + information from them. If there are no "provider" sections on + the DOF then we just return. */ + section = (struct dtrace_dof_sect *) DTRACE_DOF_PTR (dof, + DOF_UINT (dof, dof->dofh_secoff)); + for (i = 0; i < DOF_UINT (dof, dof->dofh_secnum); i++, section++) + if (DOF_UINT (dof, section->dofs_type) == DTRACE_DOF_SECT_TYPE_PROVIDER) + { + struct dtrace_dof_provider *provider = (struct dtrace_dof_provider *) + DTRACE_DOF_PTR (dof, DOF_UINT (dof, section->dofs_offset)); + struct dtrace_dof_sect *strtab_s + = DTRACE_DOF_SECT (dof, DOF_UINT (dof, provider->dofpv_strtab)); + struct dtrace_dof_sect *probes_s + = DTRACE_DOF_SECT (dof, DOF_UINT (dof, provider->dofpv_probes)); + struct dtrace_dof_sect *args_s + = DTRACE_DOF_SECT (dof, DOF_UINT (dof, provider->dofpv_prargs)); + struct dtrace_dof_sect *offsets_s + = DTRACE_DOF_SECT (dof, DOF_UINT (dof, provider->dofpv_proffs)); + struct dtrace_dof_sect *eoffsets_s + = DTRACE_DOF_SECT (dof, DOF_UINT (dof, provider->dofpv_prenoffs)); + char *strtab = DTRACE_DOF_PTR (dof, DOF_UINT (dof, strtab_s->dofs_offset)); + char *offtab = DTRACE_DOF_PTR (dof, DOF_UINT (dof, offsets_s->dofs_offset)); + char *eofftab = DTRACE_DOF_PTR (dof, DOF_UINT (dof, eoffsets_s->dofs_offset)); + char *argtab = DTRACE_DOF_PTR (dof, DOF_UINT (dof, args_s->dofs_offset)); + unsigned int entsize = DOF_UINT (dof, probes_s->dofs_entsize); + int num_probes; + + /* Very, unlikely, but could crash gdb if not handled + properly. */ + if (entsize == 0) + goto invalid_dof_data; + + num_probes = DOF_UINT (dof, probes_s->dofs_size) / entsize; + + for (i = 0; i < num_probes; i++) + { + struct dtrace_dof_probe *probe = (struct dtrace_dof_probe *) + DTRACE_DOF_PTR (dof, DOF_UINT (dof, probes_s->dofs_offset) + + (i * DOF_UINT (dof, probes_s->dofs_entsize))); + + dtrace_process_dof_probe (objfile, + gdbarch, probesp, + dof, probe, + provider, strtab, offtab, eofftab, argtab, + DOF_UINT (dof, strtab_s->dofs_size)); + } + } + + return; + + invalid_dof_data: + complaint (&symfile_complaints, + _("skipping section '%s' which does not contain valid DOF data."), + sect->name); +} + +/* Helper function to build the GDB internal expressiosn that, once + evaluated, will calculate the values of the arguments of a given + PROBE. */ + +static void +dtrace_build_arg_exprs (struct dtrace_probe *probe, + struct gdbarch *gdbarch) +{ + struct parser_state pstate; + struct dtrace_probe_arg *arg; + int i; + + probe->args_expr_built = 1; + + /* Iterate over the arguments in the probe and build the + corresponding GDB internal expression that will generate the + value of the argument when executed at the PC of the probe. */ + for (i = 0; i < probe->probe_argc; i++) + { + struct cleanup *back_to; + + arg = VEC_index (dtrace_probe_arg_s, probe->args, i); + + /* Initialize the expression buffer in the parser state. The + language does not matter, since we are using our own + parser. */ + initialize_expout (&pstate, 10, current_language, gdbarch); + back_to = make_cleanup (free_current_contents, &pstate.expout); + + /* The argument value, which is ABI dependent and casted to + `long int'. */ + gdbarch_dtrace_parse_probe_argument (gdbarch, &pstate, i); + + discard_cleanups (back_to); + + /* Casting to the expected type, but only if the type was + recognized at probe load time. Otherwise the argument will + be evaluated as the long integer passed to the probe. */ + if (arg->type != NULL) + { + write_exp_elt_opcode (&pstate, UNOP_CAST); + write_exp_elt_type (&pstate, arg->type); + write_exp_elt_opcode (&pstate, UNOP_CAST); + } + + reallocate_expout (&pstate); + arg->expr = pstate.expout; + prefixify_expression (arg->expr); + } +} + +/* Helper function to return the Nth argument of a given PROBE. */ + +static struct dtrace_probe_arg * +dtrace_get_arg (struct dtrace_probe *probe, unsigned n, + struct gdbarch *gdbarch) +{ + if (!probe->args_expr_built) + dtrace_build_arg_exprs (probe, gdbarch); + + return VEC_index (dtrace_probe_arg_s, probe->args, n); +} + +/* Implementation of the get_probes method. */ + +static void +dtrace_get_probes (VEC (probe_p) **probesp, struct objfile *objfile) +{ + bfd *abfd = objfile->obfd; + asection *sect = NULL; + + /* Do nothing in case this is a .debug file, instead of the objfile + itself. */ + if (objfile->separate_debug_objfile_backlink != NULL) + return; + + /* Iterate over the sections in OBJFILE looking for DTrace + information. */ + for (sect = abfd->sections; sect != NULL; sect = sect->next) + { + if (elf_section_data (sect)->this_hdr.sh_type == SHT_SUNW_dof) + { + struct dtrace_dof_hdr *dof; + + /* Read the contents of the DOF section and then process it to + extract the information of any probe defined into it. */ + if (!bfd_malloc_and_get_section (abfd, sect, (bfd_byte **) &dof)) + complaint (&symfile_complaints, + _("could not obtain the contents of" + "section '%s' in objfile `%s'."), + sect->name, abfd->filename); + + dtrace_process_dof (sect, objfile, probesp, dof); + xfree (dof); + } + } +} + +/* Helper function to determine whether a given probe is "enabled" or + "disabled". A disabled probe is a probe in which one or more + enablers are disabled. */ + +static int +dtrace_probe_is_enabled (struct dtrace_probe *probe) +{ + int i; + struct gdbarch *gdbarch = probe->p.arch; + struct dtrace_probe_enabler *enabler; + + for (i = 0; + VEC_iterate (dtrace_probe_enabler_s, probe->enablers, i, enabler); + i++) + if (!gdbarch_dtrace_probe_is_enabled (gdbarch, enabler->address)) + return 0; + + return 1; +} + +/* Implementation of the get_probe_address method. */ + +static CORE_ADDR +dtrace_get_probe_address (struct probe *probe, struct objfile *objfile) +{ + gdb_assert (probe->pops == &dtrace_probe_ops); + return probe->address + ANOFFSET (objfile->section_offsets, + SECT_OFF_DATA (objfile)); +} + +/* Implementation of the get_probe_argument_count method. */ + +static unsigned +dtrace_get_probe_argument_count (struct probe *probe_generic, + struct frame_info *frame) +{ + struct dtrace_probe *dtrace_probe = (struct dtrace_probe *) probe_generic; + + gdb_assert (probe_generic->pops == &dtrace_probe_ops); + + return dtrace_probe->probe_argc; +} + +/* Implementation of the can_evaluate_probe_arguments method. */ + +static int +dtrace_can_evaluate_probe_arguments (struct probe *probe_generic) +{ + struct gdbarch *gdbarch = probe_generic->arch; + + gdb_assert (probe_generic->pops == &dtrace_probe_ops); + return gdbarch_dtrace_parse_probe_argument_p (gdbarch); +} + +/* Implementation of the evaluate_probe_argument method. */ + +static struct value * +dtrace_evaluate_probe_argument (struct probe *probe_generic, unsigned n, + struct frame_info *frame) +{ + struct gdbarch *gdbarch = probe_generic->arch; + struct dtrace_probe *dtrace_probe = (struct dtrace_probe *) probe_generic; + struct dtrace_probe_arg *arg; + int pos = 0; + + gdb_assert (probe_generic->pops == &dtrace_probe_ops); + + arg = dtrace_get_arg (dtrace_probe, n, gdbarch); + return evaluate_subexp_standard (arg->type, arg->expr, &pos, EVAL_NORMAL); +} + +/* Implementation of the compile_to_ax method. */ + +static void +dtrace_compile_to_ax (struct probe *probe_generic, struct agent_expr *expr, + struct axs_value *value, unsigned n) +{ + struct dtrace_probe *dtrace_probe = (struct dtrace_probe *) probe_generic; + struct dtrace_probe_arg *arg; + union exp_element *pc; + + gdb_assert (probe_generic->pops == &dtrace_probe_ops); + + arg = dtrace_get_arg (dtrace_probe, n, expr->gdbarch); + + pc = arg->expr->elts; + gen_expr (arg->expr, &pc, expr, value); + + require_rvalue (expr, value); + value->type = arg->type; +} + +/* Implementation of the probe_destroy method. */ + +static void +dtrace_probe_destroy (struct probe *probe_generic) +{ + struct dtrace_probe *probe = (struct dtrace_probe *) probe_generic; + struct dtrace_probe_arg *arg; + int i; + + gdb_assert (probe_generic->pops == &dtrace_probe_ops); + + for (i = 0; VEC_iterate (dtrace_probe_arg_s, probe->args, i, arg); i++) + { + xfree (arg->type_str); + xfree (arg->expr); + } + + VEC_free (dtrace_probe_enabler_s, probe->enablers); + VEC_free (dtrace_probe_arg_s, probe->args); +} + +/* Implementation of the type_name method. */ + +static const char * +dtrace_type_name (struct probe *probe_generic) +{ + gdb_assert (probe_generic->pops == &dtrace_probe_ops); + return "dtrace"; +} + +/* Implementation of the gen_info_probes_table_header method. */ + +static void +dtrace_gen_info_probes_table_header (VEC (info_probe_column_s) **heads) +{ + info_probe_column_s dtrace_probe_column; + + dtrace_probe_column.field_name = "enabled"; + dtrace_probe_column.print_name = _("Enabled"); + + VEC_safe_push (info_probe_column_s, *heads, &dtrace_probe_column); +} + +/* Implementation of the gen_info_probes_table_values method. */ + +static void +dtrace_gen_info_probes_table_values (struct probe *probe_generic, + VEC (const_char_ptr) **ret) +{ + struct dtrace_probe *probe = (struct dtrace_probe *) probe_generic; + const char *val = NULL; + + gdb_assert (probe_generic->pops == &dtrace_probe_ops); + + if (VEC_empty (dtrace_probe_enabler_s, probe->enablers)) + val = "always"; + else if (!gdbarch_dtrace_probe_is_enabled_p (probe_generic->arch)) + val = "unknown"; + else if (dtrace_probe_is_enabled (probe)) + val = "yes"; + else + val = "no"; + + VEC_safe_push (const_char_ptr, *ret, val); +} + +/* Implementation of the enable_probe method. */ + +static void +dtrace_enable_probe (struct probe *probe) +{ + struct gdbarch *gdbarch = probe->arch; + struct dtrace_probe *dtrace_probe = (struct dtrace_probe *) probe; + struct dtrace_probe_enabler *enabler; + int i; + + gdb_assert (probe->pops == &dtrace_probe_ops); + + /* Enabling a dtrace probe implies patching the text section of the + running process, so make sure the inferior is indeed running. */ + if (ptid_equal (inferior_ptid, null_ptid)) + error (_("No inferior running")); + + /* Fast path. */ + if (dtrace_probe_is_enabled (dtrace_probe)) + return; + + /* Iterate over all defined enabler in the given probe and enable + them all using the corresponding gdbarch hook. */ + + for (i = 0; + VEC_iterate (dtrace_probe_enabler_s, dtrace_probe->enablers, i, enabler); + i++) + if (gdbarch_dtrace_enable_probe_p (gdbarch)) + gdbarch_dtrace_enable_probe (gdbarch, enabler->address); +} + + +/* Implementation of the disable_probe method. */ + +static void +dtrace_disable_probe (struct probe *probe) +{ + struct gdbarch *gdbarch = probe->arch; + struct dtrace_probe *dtrace_probe = (struct dtrace_probe *) probe; + struct dtrace_probe_enabler *enabler; + int i; + + gdb_assert (probe->pops == &dtrace_probe_ops); + + /* Disabling a dtrace probe implies patching the text section of the + running process, so make sure the inferior is indeed running. */ + if (ptid_equal (inferior_ptid, null_ptid)) + error (_("No inferior running")); + + /* Fast path. */ + if (!dtrace_probe_is_enabled (dtrace_probe)) + return; + + /* Are we trying to disable a probe that does not have any enabler + associated? */ + if (VEC_empty (dtrace_probe_enabler_s, dtrace_probe->enablers)) + error (_("Probe %s:%s cannot be disabled: no enablers."), probe->provider, probe->name); + + /* Iterate over all defined enabler in the given probe and disable + them all using the corresponding gdbarch hook. */ + + for (i = 0; + VEC_iterate (dtrace_probe_enabler_s, dtrace_probe->enablers, i, enabler); + i++) + if (gdbarch_dtrace_disable_probe_p (gdbarch)) + gdbarch_dtrace_disable_probe (gdbarch, enabler->address); +} + +/* DTrace probe_ops. */ + +static const struct probe_ops dtrace_probe_ops = +{ + dtrace_probe_is_linespec, + dtrace_get_probes, + dtrace_get_probe_address, + dtrace_get_probe_argument_count, + dtrace_can_evaluate_probe_arguments, + dtrace_evaluate_probe_argument, + dtrace_compile_to_ax, + NULL, /* set_semaphore */ + NULL, /* clear_semaphore */ + dtrace_probe_destroy, + dtrace_type_name, + dtrace_gen_info_probes_table_header, + dtrace_gen_info_probes_table_values, + dtrace_enable_probe, + dtrace_disable_probe +}; + +/* Implementation of the `info probes dtrace' command. */ + +static void +info_probes_dtrace_command (char *arg, int from_tty) +{ + info_probes_for_ops (arg, from_tty, &dtrace_probe_ops); +} + +void _initialize_dtrace_probe (void); + +void +_initialize_dtrace_probe (void) +{ + VEC_safe_push (probe_ops_cp, all_probe_ops, &dtrace_probe_ops); + + add_cmd ("dtrace", class_info, info_probes_dtrace_command, + _("\ +Show information about DTrace static probes.\n\ +Usage: info probes dtrace [PROVIDER [NAME [OBJECT]]]\n\ +Each argument is a regular expression, used to select probes.\n\ +PROVIDER matches probe provider names.\n\ +NAME matches the probe names.\n\ +OBJECT matches the executable or shared library name."), + info_probes_cmdlist_get ()); +} |