perf/Documentation/jitdump-specification.txt

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17 …s the jitdump file format. The file is generated by Just-In-time compiler runtimes to save meta-da…
21 The format of the file is binary. It is self-describing in terms of endianness and is portable acro…
27 …uential accesses, i.e., append only mode. The file starts with a fixed size file header describing…
29 The header is followed by a series of records, each starting with a fixed size header describing th…
34 III/ Jitdump file header format
36 Each jitdump file starts with a fixed size header containing the following fields in order:
39 * uint32_t magic     : a magic number tagging the file type. The value is 4-byte long and represent…
40 * uint32_t version   : a 4-byte value representing the format version. It is currently set to 1
41 * uint32_t total_size: size in bytes of file header
49 …* bit 0: JITDUMP_FLAGS_ARCH_TIMESTAMP : set if the jitdump file is using an architecture-specific …
51 IV/ Record header
53 The file header is immediately followed by records. Each record starts with a fixed size header des…
55 The record header is specified in order as follows:
57 * uint32_t total_size: the size in bytes of the record including the header.
67  The payload of the record must immediately follow the record header without padding.
72   The record has the following fields following the fixed-size record header in order:
82   The record header total_size field is inclusive of all components:
83   * record header
84   * fixed-sized fields
89 …dentify each jitted function. The index can be a monotonically increasing 64-bit value. Each time …
98   The record has the following fields following the fixed-size record header in order:
121 The record has the following fields following the fixed-size record header in order:
146 The JIT_CODE_CLOSE record does not have any specific fields, the record header contains all the inf…
156 The record has the following fields following the fixed-size record header in order:
159 uint64_t eh_frame_hdr_size  : the size in bytes of the DWARF EH Frame Header at the start of the un…
161 const char unwinding_data[n]: an array of unwinding data, consisting of the EH Frame Header, follow…
164 The EH Frame header follows the Linux Standard Base (LSB) specification as described in the documen…
167 …escribed in the document at https://refspecs.linuxbase.org/LSB_3.0.0/LSB-PDA/LSB-PDA/ehframechpt.h…
170 …e process). If the unwinding data was not mapped, then only the EH Frame Header will be read, whic…