diff options
| -rw-r--r-- | gdb/ChangeLog | 27 | ||||
| -rw-r--r-- | gdb/NEWS | 6 | ||||
| -rw-r--r-- | gdb/amd64-linux-nat.c | 6 | ||||
| -rw-r--r-- | gdb/btrace.c | 156 | ||||
| -rw-r--r-- | gdb/common/btrace-common.h | 27 | ||||
| -rw-r--r-- | gdb/common/linux-btrace.c | 97 | ||||
| -rw-r--r-- | gdb/common/linux-btrace.h | 15 | ||||
| -rw-r--r-- | gdb/doc/gdb.texinfo | 8 | ||||
| -rw-r--r-- | gdb/gdbserver/ChangeLog | 10 | ||||
| -rw-r--r-- | gdb/gdbserver/linux-low.c | 36 | ||||
| -rw-r--r-- | gdb/gdbserver/server.c | 11 | ||||
| -rw-r--r-- | gdb/gdbserver/target.h | 9 | ||||
| -rw-r--r-- | gdb/i386-linux-nat.c | 6 | ||||
| -rw-r--r-- | gdb/remote.c | 23 | ||||
| -rw-r--r-- | gdb/target.c | 9 | ||||
| -rw-r--r-- | gdb/target.h | 15 |
16 files changed, 370 insertions, 91 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 5cdf569..fc1f23d 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,32 @@ 2014-01-16 Markus Metzger <markus.t.metzger@intel.com> + * common/linux-btrace.c (perf_event_read_bts, linux_read_btrace): + Support delta reads. + (linux_disable_btrace): Change return type. + * common/linux-btrace.h (linux_read_btrace): Change parameters + and return type to allow error reporting. Update users. + (linux_disable_btrace): Change return type. Update users. + * common/btrace-common.h (btrace_read_type) <BTRACE_READ_DELTA>: + New. + (btrace_error): New. + (btrace_block) <begin>: Comment on BEGIN == 0. + * btrace.c (btrace_compute_ftrace): Start from the end of + the current trace. + (btrace_stitch_trace, btrace_clear_history): New. + (btrace_fetch): Read delta trace, return if replaying. + (btrace_clear): Move clear history code to btrace_clear_history. + (parse_xml_btrace): Throw an error if parsing failed. + * target.h (struct target_ops) <to_read_btrace>: Change parameters + and return type to allow error reporting. + (target_read_btrace): Change parameters and return type to allow + error reporting. + * target.c (target_read_btrace): Update. + * remote.c (remote_read_btrace): Support delta reads. Pass + errors on. + * NEWS: Announce it. + +2014-01-16 Markus Metzger <markus.t.metzger@intel.com> + * record.h (record_btrace_frame_unwind) (record_btrace_tailcall_frame_unwind): New declarations. * dwarf2-frame: Include record.h @@ -22,6 +22,12 @@ For locations inside the execution trace, the back trace is computed based on the information stored in the execution trace. +* New remote packets + +qXfer:btrace:read's annex + The qXfer:btrace:read packet supports a new annex 'delta' to read + branch trace incrementally. + *** Changes in GDB 7.7 * Improved support for process record-replay and reverse debugging on diff --git a/gdb/amd64-linux-nat.c b/gdb/amd64-linux-nat.c index 7c967f8..55973a6 100644 --- a/gdb/amd64-linux-nat.c +++ b/gdb/amd64-linux-nat.c @@ -1173,10 +1173,10 @@ amd64_linux_enable_btrace (ptid_t ptid) static void amd64_linux_disable_btrace (struct btrace_target_info *tinfo) { - int errcode = linux_disable_btrace (tinfo); + enum btrace_error errcode = linux_disable_btrace (tinfo); - if (errcode != 0) - error (_("Could not disable branch tracing: %s."), safe_strerror (errcode)); + if (errcode != BTRACE_ERR_NONE) + error (_("Could not disable branch tracing.")); } /* Teardown branch tracing. */ diff --git a/gdb/btrace.c b/gdb/btrace.c index ba87e16..28970c3 100644 --- a/gdb/btrace.c +++ b/gdb/btrace.c @@ -599,9 +599,9 @@ btrace_compute_ftrace (struct btrace_thread_info *btinfo, DEBUG ("compute ftrace"); gdbarch = target_gdbarch (); - begin = NULL; - end = NULL; - level = INT_MAX; + begin = btinfo->begin; + end = btinfo->end; + level = begin != NULL ? -btinfo->level : INT_MAX; blk = VEC_length (btrace_block_s, btrace); while (blk != 0) @@ -728,27 +728,158 @@ btrace_teardown (struct thread_info *tp) btrace_clear (tp); } +/* Adjust the block trace in order to stitch old and new trace together. + BTRACE is the new delta trace between the last and the current stop. + BTINFO is the old branch trace until the last stop. + May modify BTRACE as well as the existing trace in BTINFO. + Return 0 on success, -1 otherwise. */ + +static int +btrace_stitch_trace (VEC (btrace_block_s) **btrace, + const struct btrace_thread_info *btinfo) +{ + struct btrace_function *last_bfun; + struct btrace_insn *last_insn; + btrace_block_s *first_new_block; + + /* If we don't have trace, there's nothing to do. */ + if (VEC_empty (btrace_block_s, *btrace)) + return 0; + + last_bfun = btinfo->end; + gdb_assert (last_bfun != NULL); + + /* Beware that block trace starts with the most recent block, so the + chronologically first block in the new trace is the last block in + the new trace's block vector. */ + first_new_block = VEC_last (btrace_block_s, *btrace); + last_insn = VEC_last (btrace_insn_s, last_bfun->insn); + + /* If the current PC at the end of the block is the same as in our current + trace, there are two explanations: + 1. we executed the instruction and some branch brought us back. + 2. we have not made any progress. + In the first case, the delta trace vector should contain at least two + entries. + In the second case, the delta trace vector should contain exactly one + entry for the partial block containing the current PC. Remove it. */ + if (first_new_block->end == last_insn->pc + && VEC_length (btrace_block_s, *btrace) == 1) + { + VEC_pop (btrace_block_s, *btrace); + return 0; + } + + DEBUG ("stitching %s to %s", ftrace_print_insn_addr (last_insn), + core_addr_to_string_nz (first_new_block->end)); + + /* Do a simple sanity check to make sure we don't accidentally end up + with a bad block. This should not occur in practice. */ + if (first_new_block->end < last_insn->pc) + { + warning (_("Error while trying to read delta trace. Falling back to " + "a full read.")); + return -1; + } + + /* We adjust the last block to start at the end of our current trace. */ + gdb_assert (first_new_block->begin == 0); + first_new_block->begin = last_insn->pc; + + /* We simply pop the last insn so we can insert it again as part of + the normal branch trace computation. + Since instruction iterators are based on indices in the instructions + vector, we don't leave any pointers dangling. */ + DEBUG ("pruning insn at %s for stitching", + ftrace_print_insn_addr (last_insn)); + + VEC_pop (btrace_insn_s, last_bfun->insn); + + /* The instructions vector may become empty temporarily if this has + been the only instruction in this function segment. + This violates the invariant but will be remedied shortly by + btrace_compute_ftrace when we add the new trace. */ + return 0; +} + +/* Clear the branch trace histories in BTINFO. */ + +static void +btrace_clear_history (struct btrace_thread_info *btinfo) +{ + xfree (btinfo->insn_history); + xfree (btinfo->call_history); + xfree (btinfo->replay); + + btinfo->insn_history = NULL; + btinfo->call_history = NULL; + btinfo->replay = NULL; +} + /* See btrace.h. */ void btrace_fetch (struct thread_info *tp) { struct btrace_thread_info *btinfo; + struct btrace_target_info *tinfo; VEC (btrace_block_s) *btrace; struct cleanup *cleanup; + int errcode; DEBUG ("fetch thread %d (%s)", tp->num, target_pid_to_str (tp->ptid)); + btrace = NULL; btinfo = &tp->btrace; - if (btinfo->target == NULL) + tinfo = btinfo->target; + if (tinfo == NULL) + return; + + /* There's no way we could get new trace while replaying. + On the other hand, delta trace would return a partial record with the + current PC, which is the replay PC, not the last PC, as expected. */ + if (btinfo->replay != NULL) return; - btrace = target_read_btrace (btinfo->target, BTRACE_READ_NEW); cleanup = make_cleanup (VEC_cleanup (btrace_block_s), &btrace); + /* Let's first try to extend the trace we already have. */ + if (btinfo->end != NULL) + { + errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_DELTA); + if (errcode == 0) + { + /* Success. Let's try to stitch the traces together. */ + errcode = btrace_stitch_trace (&btrace, btinfo); + } + else + { + /* We failed to read delta trace. Let's try to read new trace. */ + errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_NEW); + + /* If we got any new trace, discard what we have. */ + if (errcode == 0 && !VEC_empty (btrace_block_s, btrace)) + btrace_clear (tp); + } + + /* If we were not able to read the trace, we start over. */ + if (errcode != 0) + { + btrace_clear (tp); + errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_ALL); + } + } + else + errcode = target_read_btrace (&btrace, tinfo, BTRACE_READ_ALL); + + /* If we were not able to read the branch trace, signal an error. */ + if (errcode != 0) + error (_("Failed to read branch trace.")); + + /* Compute the trace, provided we have any. */ if (!VEC_empty (btrace_block_s, btrace)) { - btrace_clear (tp); + btrace_clear_history (btinfo); btrace_compute_ftrace (btinfo, btrace); } @@ -783,13 +914,7 @@ btrace_clear (struct thread_info *tp) btinfo->begin = NULL; btinfo->end = NULL; - xfree (btinfo->insn_history); - xfree (btinfo->call_history); - xfree (btinfo->replay); - - btinfo->insn_history = NULL; - btinfo->call_history = NULL; - btinfo->replay = NULL; + btrace_clear_history (btinfo); } /* See btrace.h. */ @@ -881,10 +1006,7 @@ parse_xml_btrace (const char *buffer) errcode = gdb_xml_parse_quick (_("btrace"), "btrace.dtd", btrace_elements, buffer, &btrace); if (errcode != 0) - { - do_cleanups (cleanup); - return NULL; - } + error (_("Error parsing branch trace.")); /* Keep parse results. */ discard_cleanups (cleanup); diff --git a/gdb/common/btrace-common.h b/gdb/common/btrace-common.h index 1d389af..25617bb 100644 --- a/gdb/common/btrace-common.h +++ b/gdb/common/btrace-common.h @@ -42,7 +42,9 @@ asynchronous, e.g. interrupts. */ struct btrace_block { - /* The address of the first byte of the first instruction in the block. */ + /* The address of the first byte of the first instruction in the block. + The address may be zero if we do not know the beginning of this block, + such as for the first block in a delta trace. */ CORE_ADDR begin; /* The address of the first byte of the last instruction in the block. */ @@ -67,7 +69,28 @@ enum btrace_read_type BTRACE_READ_ALL, /* Send all available trace, if it changed. */ - BTRACE_READ_NEW + BTRACE_READ_NEW, + + /* Send the trace since the last request. This will fail if the trace + buffer overflowed. */ + BTRACE_READ_DELTA +}; + +/* Enumeration of btrace errors. */ + +enum btrace_error +{ + /* No error. Everything is OK. */ + BTRACE_ERR_NONE, + + /* An unknown error. */ + BTRACE_ERR_UNKNOWN, + + /* Branch tracing is not supported on this system. */ + BTRACE_ERR_NOT_SUPPORTED, + + /* The branch trace buffer overflowed; no delta read possible. */ + BTRACE_ERR_OVERFLOW }; #endif /* BTRACE_COMMON_H */ diff --git a/gdb/common/linux-btrace.c b/gdb/common/linux-btrace.c index e469900..218e0ce 100644 --- a/gdb/common/linux-btrace.c +++ b/gdb/common/linux-btrace.c @@ -172,11 +172,11 @@ perf_event_sample_ok (const struct perf_event_sample *sample) static VEC (btrace_block_s) * perf_event_read_bts (struct btrace_target_info* tinfo, const uint8_t *begin, - const uint8_t *end, const uint8_t *start) + const uint8_t *end, const uint8_t *start, size_t size) { VEC (btrace_block_s) *btrace = NULL; struct perf_event_sample sample; - size_t read = 0, size = (end - begin); + size_t read = 0; struct btrace_block block = { 0, 0 }; struct regcache *regcache; @@ -252,6 +252,13 @@ perf_event_read_bts (struct btrace_target_info* tinfo, const uint8_t *begin, block.end = psample->bts.from; } + /* Push the last block (i.e. the first one of inferior execution), as well. + We don't know where it ends, but we know where it starts. If we're + reading delta trace, we can fill in the start address later on. + Otherwise we will prune it. */ + block.begin = 0; + VEC_safe_push (btrace_block_s, btrace, &block); + return btrace; } @@ -476,7 +483,7 @@ linux_enable_btrace (ptid_t ptid) /* See linux-btrace.h. */ -int +enum btrace_error linux_disable_btrace (struct btrace_target_info *tinfo) { int errcode; @@ -484,12 +491,12 @@ linux_disable_btrace (struct btrace_target_info *tinfo) errno = 0; errcode = munmap (tinfo->buffer, perf_event_mmap_size (tinfo)); if (errcode != 0) - return errno; + return BTRACE_ERR_UNKNOWN; close (tinfo->file); xfree (tinfo); - return 0; + return BTRACE_ERR_NONE; } /* Check whether the branch trace has changed. */ @@ -504,21 +511,24 @@ linux_btrace_has_changed (struct btrace_target_info *tinfo) /* See linux-btrace.h. */ -VEC (btrace_block_s) * -linux_read_btrace (struct btrace_target_info *tinfo, +enum btrace_error +linux_read_btrace (VEC (btrace_block_s) **btrace, + struct btrace_target_info *tinfo, enum btrace_read_type type) { - VEC (btrace_block_s) *btrace = NULL; volatile struct perf_event_mmap_page *header; const uint8_t *begin, *end, *start; - unsigned long data_head, retries = 5; - size_t buffer_size; + unsigned long data_head, data_tail, retries = 5; + size_t buffer_size, size; + /* For delta reads, we return at least the partial last block containing + the current PC. */ if (type == BTRACE_READ_NEW && !linux_btrace_has_changed (tinfo)) - return NULL; + return BTRACE_ERR_NONE; header = perf_event_header (tinfo); buffer_size = perf_event_buffer_size (tinfo); + data_tail = tinfo->data_head; /* We may need to retry reading the trace. See below. */ while (retries--) @@ -526,23 +536,45 @@ linux_read_btrace (struct btrace_target_info *tinfo, data_head = header->data_head; /* Delete any leftover trace from the previous iteration. */ - VEC_free (btrace_block_s, btrace); + VEC_free (btrace_block_s, *btrace); - /* If there's new trace, let's read it. */ - if (data_head != tinfo->data_head) + if (type == BTRACE_READ_DELTA) { - /* Data_head keeps growing; the buffer itself is circular. */ - begin = perf_event_buffer_begin (tinfo); - start = begin + data_head % buffer_size; - - if (data_head <= buffer_size) - end = start; - else - end = perf_event_buffer_end (tinfo); + /* Determine the number of bytes to read and check for buffer + overflows. */ + + /* Check for data head overflows. We might be able to recover from + those but they are very unlikely and it's not really worth the + effort, I think. */ + if (data_head < data_tail) + return BTRACE_ERR_OVERFLOW; + + /* If the buffer is smaller than the trace delta, we overflowed. */ + size = data_head - data_tail; + if (buffer_size < size) + return BTRACE_ERR_OVERFLOW; + } + else + { + /* Read the entire buffer. */ + size = buffer_size; - btrace = perf_event_read_bts (tinfo, begin, end, start); + /* Adjust the size if the buffer has not overflowed, yet. */ + if (data_head < size) + size = data_head; } + /* Data_head keeps growing; the buffer itself is circular. */ + begin = perf_event_buffer_begin (tinfo); + start = begin + data_head % buffer_size; + + if (data_head <= buffer_size) + end = start; + else + end = perf_event_buffer_end (tinfo); + + *btrace = perf_event_read_bts (tinfo, begin, end, start, size); + /* The stopping thread notifies its ptracer before it is scheduled out. On multi-core systems, the debugger might therefore run while the kernel might be writing the last branch trace records. @@ -554,7 +586,13 @@ linux_read_btrace (struct btrace_target_info *tinfo, tinfo->data_head = data_head; - return btrace; + /* Prune the incomplete last block (i.e. the first one of inferior execution) + if we're not doing a delta read. There is no way of filling in its zeroed + BEGIN element. */ + if (!VEC_empty (btrace_block_s, *btrace) && type != BTRACE_READ_DELTA) + VEC_pop (btrace_block_s, *btrace); + + return BTRACE_ERR_NONE; } #else /* !HAVE_LINUX_PERF_EVENT_H */ @@ -577,19 +615,20 @@ linux_enable_btrace (ptid_t ptid) /* See linux-btrace.h. */ -int +enum btrace_error linux_disable_btrace (struct btrace_target_info *tinfo) { - return ENOSYS; + return BTRACE_ERR_NOT_SUPPORTED; } /* See linux-btrace.h. */ -VEC (btrace_block_s) * -linux_read_btrace (struct btrace_target_info *tinfo, +enum btrace_error +linux_read_btrace (VEC (btrace_block_s) **btrace, + struct btrace_target_info *tinfo, enum btrace_read_type type) { - return NULL; + return BTRACE_ERR_NOT_SUPPORTED; } #endif /* !HAVE_LINUX_PERF_EVENT_H */ diff --git a/gdb/common/linux-btrace.h b/gdb/common/linux-btrace.h index 32a0403..a97b697 100644 --- a/gdb/common/linux-btrace.h +++ b/gdb/common/linux-btrace.h @@ -61,17 +61,18 @@ struct btrace_target_info int ptr_bits; }; -/* Check whether branch tracing is supported. */ +/* See to_supports_btrace in target.h. */ extern int linux_supports_btrace (void); -/* Enable branch tracing for @ptid. */ +/* See to_enable_btrace in target.h. */ extern struct btrace_target_info *linux_enable_btrace (ptid_t ptid); -/* Disable branch tracing and deallocate @tinfo. */ -extern int linux_disable_btrace (struct btrace_target_info *tinfo); +/* See to_disable_btrace in target.h. */ +extern enum btrace_error linux_disable_btrace (struct btrace_target_info *ti); -/* Read branch trace data. */ -extern VEC (btrace_block_s) *linux_read_btrace (struct btrace_target_info *, - enum btrace_read_type); +/* See to_read_btrace in target.h. */ +extern enum btrace_error linux_read_btrace (VEC (btrace_block_s) **btrace, + struct btrace_target_info *btinfo, + enum btrace_read_type type); #endif /* LINUX_BTRACE_H */ diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index d0f2f71..57071d1 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -39978,6 +39978,14 @@ Returns all available branch trace. @item new Returns all available branch trace if the branch trace changed since the last read request. + +@item delta +Returns the new branch trace since the last read request. Adds a new +block to the end of the trace that begins at zero and ends at the source +location of the first branch in the trace buffer. This extra block is +used to stitch traces together. + +If the trace buffer overflowed, returns an error indicating the overflow. @end table This packet is not probed by default; the remote stub must request it diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog index 7347f08..5884639 100644 --- a/gdb/gdbserver/ChangeLog +++ b/gdb/gdbserver/ChangeLog @@ -1,3 +1,13 @@ +2014-01-16 Markus Metzger <markus.t.metzger@intel.com> + + * target.h (target_ops) <read_btrace>: Change parameters and + return type to allow error reporting. + * server.c (handle_qxfer_btrace): Support delta reads. Pass + trace reading errors on. + * linux-low.c (linux_low_read_btrace): Pass trace reading + errors on. + (linux_low_disable_btrace): New. + 2014-01-15 Doug Evans <dje@google.com> * inferiors.c (thread_id_to_gdb_id): Delete. diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c index 2bc619a..01d0e84 100644 --- a/gdb/gdbserver/linux-low.c +++ b/gdb/gdbserver/linux-low.c @@ -5705,7 +5705,7 @@ linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf, #ifdef HAVE_LINUX_BTRACE -/* Enable branch tracing. */ +/* See to_enable_btrace target method. */ static struct btrace_target_info * linux_low_enable_btrace (ptid_t ptid) @@ -5725,17 +5725,39 @@ linux_low_enable_btrace (ptid_t ptid) return tinfo; } -/* Read branch trace data as btrace xml document. */ +/* See to_disable_btrace target method. */ -static void +static int +linux_low_disable_btrace (struct btrace_target_info *tinfo) +{ + enum btrace_error err; + + err = linux_disable_btrace (tinfo); + return (err == BTRACE_ERR_NONE ? 0 : -1); +} + +/* See to_read_btrace target method. */ + +static int linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer, int type) { VEC (btrace_block_s) *btrace; struct btrace_block *block; + enum btrace_error err; int i; - btrace = linux_read_btrace (tinfo, type); + btrace = NULL; + err = linux_read_btrace (&btrace, tinfo, type); + if (err != BTRACE_ERR_NONE) + { + if (err == BTRACE_ERR_OVERFLOW) + buffer_grow_str0 (buffer, "E.Overflow."); + else + buffer_grow_str0 (buffer, "E.Generic Error."); + + return -1; + } buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n"); buffer_grow_str (buffer, "<btrace version=\"1.0\">\n"); @@ -5744,9 +5766,11 @@ linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer, buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n", paddress (block->begin), paddress (block->end)); - buffer_grow_str (buffer, "</btrace>\n"); + buffer_grow_str0 (buffer, "</btrace>\n"); VEC_free (btrace_block_s, btrace); + + return 0; } #endif /* HAVE_LINUX_BTRACE */ @@ -5819,7 +5843,7 @@ static struct target_ops linux_target_ops = { #ifdef HAVE_LINUX_BTRACE linux_supports_btrace, linux_low_enable_btrace, - linux_disable_btrace, + linux_low_disable_btrace, linux_low_read_btrace, #else NULL, diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c index 9ae28f8..28ea048 100644 --- a/gdb/gdbserver/server.c +++ b/gdb/gdbserver/server.c @@ -1348,7 +1348,7 @@ handle_qxfer_btrace (const char *annex, { static struct buffer cache; struct thread_info *thread; - int type; + int type, result; if (the_target->read_btrace == NULL || writebuf != NULL) return -2; @@ -1380,6 +1380,8 @@ handle_qxfer_btrace (const char *annex, type = BTRACE_READ_ALL; else if (strcmp (annex, "new") == 0) type = BTRACE_READ_NEW; + else if (strcmp (annex, "delta") == 0) + type = BTRACE_READ_DELTA; else { strcpy (own_buf, "E.Bad annex."); @@ -1390,7 +1392,12 @@ handle_qxfer_btrace (const char *annex, { buffer_free (&cache); - target_read_btrace (thread->btrace, &cache, type); + result = target_read_btrace (thread->btrace, &cache, type); + if (result != 0) + { + memcpy (own_buf, cache.buffer, cache.used_size); + return -3; + } } else if (offset > cache.used_size) { diff --git a/gdb/gdbserver/target.h b/gdb/gdbserver/target.h index d090a30..ae48cd7 100644 --- a/gdb/gdbserver/target.h +++ b/gdb/gdbserver/target.h @@ -356,12 +356,15 @@ struct target_ops information struct for reading and for disabling branch trace. */ struct btrace_target_info *(*enable_btrace) (ptid_t ptid); - /* Disable branch tracing. */ + /* Disable branch tracing. + Returns zero on success, non-zero otherwise. */ int (*disable_btrace) (struct btrace_target_info *tinfo); /* Read branch trace data into buffer. We use an int to specify the type - to break a cyclic dependency. */ - void (*read_btrace) (struct btrace_target_info *, struct buffer *, int type); + to break a cyclic dependency. + Return 0 on success; print an error message into BUFFER and return -1, + otherwise. */ + int (*read_btrace) (struct btrace_target_info *, struct buffer *, int type); /* Return true if target supports range stepping. */ int (*supports_range_stepping) (void); diff --git a/gdb/i386-linux-nat.c b/gdb/i386-linux-nat.c index 75d3fa0..fdf5dee 100644 --- a/gdb/i386-linux-nat.c +++ b/gdb/i386-linux-nat.c @@ -1084,10 +1084,10 @@ i386_linux_enable_btrace (ptid_t ptid) static void i386_linux_disable_btrace (struct btrace_target_info *tinfo) { - int errcode = linux_disable_btrace (tinfo); + enum btrace_error errcode = linux_disable_btrace (tinfo); - if (errcode != 0) - error (_("Could not disable branch tracing: %s."), safe_strerror (errcode)); + if (errcode != BTRACE_ERR_NONE) + error (_("Could not disable branch tracing.")); } /* Teardown branch tracing. */ diff --git a/gdb/remote.c b/gdb/remote.c index 10aab66..d40485a 100644 --- a/gdb/remote.c +++ b/gdb/remote.c @@ -11489,13 +11489,14 @@ remote_teardown_btrace (struct btrace_target_info *tinfo) /* Read the branch trace. */ -static VEC (btrace_block_s) * -remote_read_btrace (struct btrace_target_info *tinfo, +static enum btrace_error +remote_read_btrace (VEC (btrace_block_s) **btrace, + struct btrace_target_info *tinfo, enum btrace_read_type type) { struct packet_config *packet = &remote_protocol_packets[PACKET_qXfer_btrace]; struct remote_state *rs = get_remote_state (); - VEC (btrace_block_s) *btrace = NULL; + struct cleanup *cleanup; const char *annex; char *xml; @@ -11514,6 +11515,9 @@ remote_read_btrace (struct btrace_target_info *tinfo, case BTRACE_READ_NEW: annex = "new"; break; + case BTRACE_READ_DELTA: + annex = "delta"; + break; default: internal_error (__FILE__, __LINE__, _("Bad branch tracing read type: %u."), @@ -11522,15 +11526,14 @@ remote_read_btrace (struct btrace_target_info *tinfo, xml = target_read_stralloc (¤t_target, TARGET_OBJECT_BTRACE, annex); - if (xml != NULL) - { - struct cleanup *cleanup = make_cleanup (xfree, xml); + if (xml == NULL) + return BTRACE_ERR_UNKNOWN; - btrace = parse_xml_btrace (xml); - do_cleanups (cleanup); - } + cleanup = make_cleanup (xfree, xml); + *btrace = parse_xml_btrace (xml); + do_cleanups (cleanup); - return btrace; + return BTRACE_ERR_NONE; } static int diff --git a/gdb/target.c b/gdb/target.c index d9c27b8..a771893 100644 --- a/gdb/target.c +++ b/gdb/target.c @@ -4232,18 +4232,19 @@ target_teardown_btrace (struct btrace_target_info *btinfo) /* See target.h. */ -VEC (btrace_block_s) * -target_read_btrace (struct btrace_target_info *btinfo, +enum btrace_error +target_read_btrace (VEC (btrace_block_s) **btrace, + struct btrace_target_info *btinfo, enum btrace_read_type type) { struct target_ops *t; for (t = current_target.beneath; t != NULL; t = t->beneath) if (t->to_read_btrace != NULL) - return t->to_read_btrace (btinfo, type); + return t->to_read_btrace (btrace, btinfo, type); tcomplain (); - return NULL; + return BTRACE_ERR_NOT_SUPPORTED; } /* See target.h. */ diff --git a/gdb/target.h b/gdb/target.h index 79b9886..d6de52a 100644 --- a/gdb/target.h +++ b/gdb/target.h @@ -839,9 +839,13 @@ struct target_ops be attempting to talk to a remote target. */ void (*to_teardown_btrace) (struct btrace_target_info *tinfo); - /* Read branch trace data. */ - VEC (btrace_block_s) *(*to_read_btrace) (struct btrace_target_info *, - enum btrace_read_type); + /* Read branch trace data for the thread indicated by BTINFO into DATA. + DATA is cleared before new trace is added. + The branch trace will start with the most recent block and continue + towards older blocks. */ + enum btrace_error (*to_read_btrace) (VEC (btrace_block_s) **data, + struct btrace_target_info *btinfo, + enum btrace_read_type type); /* Stop trace recording. */ void (*to_stop_recording) (void); @@ -1998,8 +2002,9 @@ extern void target_disable_btrace (struct btrace_target_info *btinfo); extern void target_teardown_btrace (struct btrace_target_info *btinfo); /* See to_read_btrace in struct target_ops. */ -extern VEC (btrace_block_s) *target_read_btrace (struct btrace_target_info *, - enum btrace_read_type); +extern enum btrace_error target_read_btrace (VEC (btrace_block_s) **, + struct btrace_target_info *, + enum btrace_read_type); /* See to_stop_recording in struct target_ops. */ extern void target_stop_recording (void); |