diff options
| -rw-r--r-- | Documentation/admin-guide/kdump/gdbmacros.txt | 153 | ||||
| -rw-r--r-- | scripts/gdb/linux/dmesg.py | 139 |
2 files changed, 209 insertions, 83 deletions
diff --git a/Documentation/admin-guide/kdump/gdbmacros.txt b/Documentation/admin-guide/kdump/gdbmacros.txt index 220d0a80ca2c..7adece30237e 100644 --- a/Documentation/admin-guide/kdump/gdbmacros.txt +++ b/Documentation/admin-guide/kdump/gdbmacros.txt @@ -170,57 +170,111 @@ document trapinfo address the kernel panicked. end -define dump_log_idx - set $idx = $arg0 +define dump_record + set var $desc = $arg0 if ($argc > 1) - set $prev_flags = $arg1 + set var $prev_flags = $arg1 else - set $prev_flags = 0 + set var $prev_flags = 0 end - set $msg = ((struct printk_log *) (log_buf + $idx)) - set $prefix = 1 - set $newline = 1 - set $log = log_buf + $idx + sizeof(*$msg) - - # prev & LOG_CONT && !(msg->flags & LOG_PREIX) - if (($prev_flags & 8) && !($msg->flags & 4)) - set $prefix = 0 + + set var $info = &$desc->info + set var $prefix = 1 + set var $newline = 1 + + set var $begin = $desc->text_blk_lpos.begin % (1U << prb->text_data_ring.size_bits) + set var $next = $desc->text_blk_lpos.next % (1U << prb->text_data_ring.size_bits) + + # handle data-less record + if ($begin & 1) + set var $text_len = 0 + set var $log = "" + else + # handle wrapping data block + if ($begin > $next) + set var $begin = 0 + end + + # skip over descriptor id + set var $begin = $begin + sizeof(long) + + # handle truncated message + if ($next - $begin < $info->text_len) + set var $text_len = $next - $begin + else + set var $text_len = $info->text_len + end + + set var $log = &prb->text_data_ring.data[$begin] + end + + # prev & LOG_CONT && !(info->flags & LOG_PREIX) + if (($prev_flags & 8) && !($info->flags & 4)) + set var $prefix = 0 end - # msg->flags & LOG_CONT - if ($msg->flags & 8) + # info->flags & LOG_CONT + if ($info->flags & 8) # (prev & LOG_CONT && !(prev & LOG_NEWLINE)) if (($prev_flags & 8) && !($prev_flags & 2)) - set $prefix = 0 + set var $prefix = 0 end - # (!(msg->flags & LOG_NEWLINE)) - if (!($msg->flags & 2)) - set $newline = 0 + # (!(info->flags & LOG_NEWLINE)) + if (!($info->flags & 2)) + set var $newline = 0 end end if ($prefix) - printf "[%5lu.%06lu] ", $msg->ts_nsec / 1000000000, $msg->ts_nsec % 1000000000 + printf "[%5lu.%06lu] ", $info->ts_nsec / 1000000000, $info->ts_nsec % 1000000000 end - if ($msg->text_len != 0) - eval "printf \"%%%d.%ds\", $log", $msg->text_len, $msg->text_len + if ($text_len) + eval "printf \"%%%d.%ds\", $log", $text_len, $text_len end if ($newline) printf "\n" end - if ($msg->dict_len > 0) - set $dict = $log + $msg->text_len - set $idx = 0 - set $line = 1 - while ($idx < $msg->dict_len) + + # handle dictionary data + + set var $begin = $desc->dict_blk_lpos.begin % (1U << prb->dict_data_ring.size_bits) + set var $next = $desc->dict_blk_lpos.next % (1U << prb->dict_data_ring.size_bits) + + # handle data-less record + if ($begin & 1) + set var $dict_len = 0 + set var $dict = "" + else + # handle wrapping data block + if ($begin > $next) + set var $begin = 0 + end + + # skip over descriptor id + set var $begin = $begin + sizeof(long) + + # handle truncated message + if ($next - $begin < $info->dict_len) + set var $dict_len = $next - $begin + else + set var $dict_len = $info->dict_len + end + + set var $dict = &prb->dict_data_ring.data[$begin] + end + + if ($dict_len > 0) + set var $idx = 0 + set var $line = 1 + while ($idx < $dict_len) if ($line) printf " " - set $line = 0 + set var $line = 0 end - set $c = $dict[$idx] + set var $c = $dict[$idx] if ($c == '\0') printf "\n" - set $line = 1 + set var $line = 1 else if ($c < ' ' || $c >= 127 || $c == '\\') printf "\\x%02x", $c @@ -228,33 +282,40 @@ define dump_log_idx printf "%c", $c end end - set $idx = $idx + 1 + set var $idx = $idx + 1 end printf "\n" end end -document dump_log_idx - Dump a single log given its index in the log buffer. The first - parameter is the index into log_buf, the second is optional and - specified the previous log buffer's flags, used for properly - formatting continued lines. +document dump_record + Dump a single record. The first parameter is the descriptor + sequence number, the second is optional and specifies the + previous record's flags, used for properly formatting + continued lines. end define dmesg - set $i = log_first_idx - set $end_idx = log_first_idx - set $prev_flags = 0 + set var $desc_committed = 1UL << ((sizeof(long) * 8) - 1) + set var $flags_mask = 3UL << ((sizeof(long) * 8) - 2) + set var $id_mask = ~$flags_mask + + set var $desc_count = 1U << prb->desc_ring.count_bits + set var $prev_flags = 0 + + set var $id = prb->desc_ring.tail_id.counter + set var $end_id = prb->desc_ring.head_id.counter while (1) - set $msg = ((struct printk_log *) (log_buf + $i)) - if ($msg->len == 0) - set $i = 0 - else - dump_log_idx $i $prev_flags - set $i = $i + $msg->len - set $prev_flags = $msg->flags + set var $desc = &prb->desc_ring.descs[$id % $desc_count] + + # skip non-committed record + if (($desc->state_var.counter & $flags_mask) == $desc_committed) + dump_record $desc $prev_flags + set var $prev_flags = $desc->info.flags end - if ($i == $end_idx) + + set var $id = ($id + 1) & $id_mask + if ($id == $end_id) loop_break end end diff --git a/scripts/gdb/linux/dmesg.py b/scripts/gdb/linux/dmesg.py index 2fa7bb83885f..6c6022012ea8 100644 --- a/scripts/gdb/linux/dmesg.py +++ b/scripts/gdb/linux/dmesg.py @@ -16,8 +16,13 @@ import sys from linux import utils -printk_log_type = utils.CachedType("struct printk_log") - +printk_info_type = utils.CachedType("struct printk_info") +prb_data_blk_lpos_type = utils.CachedType("struct prb_data_blk_lpos") +prb_desc_type = utils.CachedType("struct prb_desc") +prb_desc_ring_type = utils.CachedType("struct prb_desc_ring") +prb_data_ring_type = utils.CachedType("struct prb_data_ring") +printk_ringbuffer_type = utils.CachedType("struct printk_ringbuffer") +atomic_long_type = utils.CachedType("atomic_long_t") class LxDmesg(gdb.Command): """Print Linux kernel log buffer.""" @@ -26,44 +31,102 @@ class LxDmesg(gdb.Command): super(LxDmesg, self).__init__("lx-dmesg", gdb.COMMAND_DATA) def invoke(self, arg, from_tty): - log_buf_addr = int(str(gdb.parse_and_eval( - "(void *)'printk.c'::log_buf")).split()[0], 16) - log_first_idx = int(gdb.parse_and_eval("'printk.c'::log_first_idx")) - log_next_idx = int(gdb.parse_and_eval("'printk.c'::log_next_idx")) - log_buf_len = int(gdb.parse_and_eval("'printk.c'::log_buf_len")) - inf = gdb.inferiors()[0] - start = log_buf_addr + log_first_idx - if log_first_idx < log_next_idx: - log_buf_2nd_half = -1 - length = log_next_idx - log_first_idx - log_buf = utils.read_memoryview(inf, start, length).tobytes() - else: - log_buf_2nd_half = log_buf_len - log_first_idx - a = utils.read_memoryview(inf, start, log_buf_2nd_half) - b = utils.read_memoryview(inf, log_buf_addr, log_next_idx) - log_buf = a.tobytes() + b.tobytes() - - length_offset = printk_log_type.get_type()['len'].bitpos // 8 - text_len_offset = printk_log_type.get_type()['text_len'].bitpos // 8 - time_stamp_offset = printk_log_type.get_type()['ts_nsec'].bitpos // 8 - text_offset = printk_log_type.get_type().sizeof - - pos = 0 - while pos < log_buf.__len__(): - length = utils.read_u16(log_buf, pos + length_offset) - if length == 0: - if log_buf_2nd_half == -1: - gdb.write("Corrupted log buffer!\n") + + # read in prb structure + prb_addr = int(str(gdb.parse_and_eval("(void *)'printk.c'::prb")).split()[0], 16) + sz = printk_ringbuffer_type.get_type().sizeof + prb = utils.read_memoryview(inf, prb_addr, sz).tobytes() + + # read in descriptor ring structure + off = printk_ringbuffer_type.get_type()['desc_ring'].bitpos // 8 + addr = prb_addr + off + sz = prb_desc_ring_type.get_type().sizeof + desc_ring = utils.read_memoryview(inf, addr, sz).tobytes() + + # read in descriptor array + off = prb_desc_ring_type.get_type()['count_bits'].bitpos // 8 + desc_ring_count = 1 << utils.read_u32(desc_ring, off) + desc_sz = prb_desc_type.get_type().sizeof + off = prb_desc_ring_type.get_type()['descs'].bitpos // 8 + addr = utils.read_ulong(desc_ring, off) + descs = utils.read_memoryview(inf, addr, desc_sz * desc_ring_count).tobytes() + + # read in text data ring structure + off = printk_ringbuffer_type.get_type()['text_data_ring'].bitpos // 8 + addr = prb_addr + off + sz = prb_data_ring_type.get_type().sizeof + text_data_ring = utils.read_memoryview(inf, addr, sz).tobytes() + + # read in text data + off = prb_data_ring_type.get_type()['size_bits'].bitpos // 8 + text_data_sz = 1 << utils.read_u32(text_data_ring, off) + off = prb_data_ring_type.get_type()['data'].bitpos // 8 + addr = utils.read_ulong(text_data_ring, off) + text_data = utils.read_memoryview(inf, addr, text_data_sz).tobytes() + + counter_off = atomic_long_type.get_type()['counter'].bitpos // 8 + + sv_off = prb_desc_type.get_type()['state_var'].bitpos // 8 + + off = prb_desc_type.get_type()['text_blk_lpos'].bitpos // 8 + begin_off = off + (prb_data_blk_lpos_type.get_type()['begin'].bitpos // 8) + next_off = off + (prb_data_blk_lpos_type.get_type()['next'].bitpos // 8) + + off = prb_desc_type.get_type()['info'].bitpos // 8 + ts_off = off + printk_info_type.get_type()['ts_nsec'].bitpos // 8 + len_off = off + printk_info_type.get_type()['text_len'].bitpos // 8 + + # definitions from kernel/printk/printk_ringbuffer.h + desc_sv_bits = utils.get_long_type().sizeof * 8 + desc_committed_mask = 1 << (desc_sv_bits - 1) + desc_reuse_mask = 1 << (desc_sv_bits - 2) + desc_flags_mask = desc_committed_mask | desc_reuse_mask + desc_id_mask = ~desc_flags_mask + + # read in tail and head descriptor ids + off = prb_desc_ring_type.get_type()['tail_id'].bitpos // 8 + tail_id = utils.read_u64(desc_ring, off + counter_off) + off = prb_desc_ring_type.get_type()['head_id'].bitpos // 8 + head_id = utils.read_u64(desc_ring, off + counter_off) + + did = tail_id + while True: + ind = did % desc_ring_count + desc_off = desc_sz * ind + + # skip non-committed record + state = utils.read_u64(descs, desc_off + sv_off + counter_off) & desc_flags_mask + if state != desc_committed_mask: + if did == head_id: break - pos = log_buf_2nd_half + did = (did + 1) & desc_id_mask continue - text_len = utils.read_u16(log_buf, pos + text_len_offset) - text_start = pos + text_offset - text = log_buf[text_start:text_start + text_len].decode( - encoding='utf8', errors='replace') - time_stamp = utils.read_u64(log_buf, pos + time_stamp_offset) + begin = utils.read_ulong(descs, desc_off + begin_off) % text_data_sz + end = utils.read_ulong(descs, desc_off + next_off) % text_data_sz + + # handle data-less record + if begin & 1 == 1: + text = "" + else: + # handle wrapping data block + if begin > end: + begin = 0 + + # skip over descriptor id + text_start = begin + utils.get_long_type().sizeof + + text_len = utils.read_u16(descs, desc_off + len_off) + + # handle truncated message + if end - text_start < text_len: + text_len = end - text_start + + text = text_data[text_start:text_start + text_len].decode( + encoding='utf8', errors='replace') + + time_stamp = utils.read_u64(descs, desc_off + ts_off) for line in text.splitlines(): msg = u"[{time:12.6f}] {line}\n".format( @@ -75,7 +138,9 @@ class LxDmesg(gdb.Command): msg = msg.encode(encoding='utf8', errors='replace') gdb.write(msg) - pos += length + if did == head_id: + break + did = (did + 1) & desc_id_mask LxDmesg() |