feat(ktrace): added ktrace-decode to turn a .ktrace recording into a SQLite database

kernel/trace/ktrace.h

@@ -2,29 +2,7 @@
 #define STELLUX_TRACE_KTRACE_H
 
 #include "common/types.h"
-
-/*
- * A .ktrace file holds one session, streamed while it records. Fields are
- * little-endian and every section is a multiple of 64 bytes.
- *
- *   +-------------------------+
- *   | file_header             |  64 bytes
- *   +-------------------------+
- *   | chunk_header            |  64 bytes, CHUNK_RECORDS
- *   | trace_record            |  record_count records of one CPU,
- *   | ...                     |  oldest first
- *   +-------------------------+
- *   | ...                     |  more chunks, CPUs interleaved
- *   +-------------------------+
- *   | chunk_header            |  CHUNK_END, last in the file
- *   +-------------------------+
- *
- * A file without a CHUNK_END chunk was cut short. Readers sort records by
- * timestamp, since an interrupt can record between a writer's clock read and
- * its slot reservation, and they drop records older than session_start_ns.
- * Fields are only appended to the headers, and version changes only for
- * incompatible layouts.
- */
+#include "trace/ktrace_format.h"
 
 namespace ktrace {
 
@@ -35,60 +13,6 @@ constexpr int32_t ERR_NOT_RECORDING = -3;
 constexpr int32_t ERR_DEVFS         = -4;
 constexpr int32_t ERR_NO_READER     = -5;
 
-constexpr char     FILE_MAGIC[]  = "STLXKTRC";
-constexpr uint16_t FILE_VERSION  = 1;
-
-constexpr uint32_t CHUNK_RECORDS = 1;
-constexpr uint32_t CHUNK_END     = 2;
-
-// An event mask holds one bit per event id
-constexpr uint16_t EVENT_ID_COUNT = 64;
-constexpr uint64_t ALL_EVENTS     = ~0ull;
-
-struct trace_record_header {
-    uint64_t    timestamp;     // Nanoseconds since boot, set by record_event()
-    uint16_t    event_id;      // ID of the event in a given trace profile
-    uint16_t    context;       // Event context information
-    uint8_t     length;        // Length of the record in 8-byte words
-    uint8_t     flags;         // Record-specific flags
-    uint16_t    reserved;
-} __attribute__((packed));
-
-static_assert(sizeof(trace_record_header) == 16, "trace_record_header size must be 16 bytes");
-
-struct trace_record {
-    trace_record_header hdr; // Event header
-    uint64_t            payload[6]; // Event specific payload
-} __attribute__((aligned(64)));
-
-static_assert(sizeof(trace_record) == 64, "trace_record size must be 64 bytes");
-struct file_header {
-    char        magic[8];           // FILE_MAGIC without its terminator
-    uint16_t    version;            // FILE_VERSION
-    uint16_t    header_size;        // sizeof(file_header)
-    uint16_t    arch;               // ELF machine number of the kernel
-    uint16_t    reserved0;
-    uint32_t    cpu_count;
-    uint32_t    record_size;        // sizeof(trace_record)
-    uint64_t    boot_unix_ns;       // Wall-clock time at boot, 0 without an RTC
-    uint64_t    session_start_ns;   // Nanoseconds since boot
-    uint64_t    event_mask;         // Event ids the session recorded, one bit each
-    uint64_t    reserved1[2];
-} __attribute__((packed));
-
-static_assert(sizeof(file_header) == 64, "file_header size must be 64 bytes");
-
-struct chunk_header {
-    uint32_t    kind;               // CHUNK_RECORDS or CHUNK_END
-    uint32_t    cpu_id;
-    uint64_t    record_count;
-    uint64_t    lost_records;       // Records the CPU dropped since its previous chunk
-    uint64_t    stop_ns;            // Nanoseconds since boot, set in CHUNK_END
-    uint64_t    reserved[4];
-} __attribute__((packed));
-
-static_assert(sizeof(chunk_header) == 64, "chunk_header size must be 64 bytes");
-
 /**
  * @brief Initializes the kernel tracing and profiling subsystem for a given CPU.
  * @note Privilege: **required**

kernel/trace/ktrace_events.h

@@ -7,76 +7,6 @@ namespace sched { struct task; }
 
 namespace ktrace {
 
-constexpr uint16_t EVENT_SCHED_SWITCH = 1;
-constexpr uint16_t EVENT_SCHED_WAKEUP = 2;
-constexpr uint16_t EVENT_SYSCALL      = 3;
-constexpr uint16_t EVENT_PAGE_FAULT   = 4;
-
-constexpr uint8_t SWITCH_REASON_PREEMPTED = 0;
-constexpr uint8_t SWITCH_REASON_YIELDED   = 1;
-constexpr uint8_t SWITCH_REASON_BLOCKED   = 2;
-constexpr uint8_t SWITCH_REASON_EXITED    = 3;
-
-constexpr uint8_t TASK_KIND_NOT_RECORDED = 0;
-constexpr uint8_t TASK_KIND_USER         = 1;
-constexpr uint8_t TASK_KIND_KERNEL       = 2;
-constexpr uint8_t TASK_KIND_IDLE         = 3;
-
-constexpr size_t TASK_NAME_BYTES = 16;
-
-struct sched_switch_payload {
-    uint32_t    prev_tid;
-    uint32_t    next_tid;
-    uint8_t     reason;
-    uint8_t     prev_kind;
-    uint8_t     next_kind;
-    uint8_t     reserved;
-    uint32_t    next_pid;   // 0 when the task belongs to no process
-    char        prev_name[TASK_NAME_BYTES];
-    char        next_name[TASK_NAME_BYTES];
-} __attribute__((packed));
-
-static_assert(sizeof(sched_switch_payload) == sizeof(trace_record::payload),
-              "sched_switch_payload must fill a record payload");
-
-struct sched_wakeup_payload {
-    uint32_t    woken_tid;
-    uint32_t    target_cpu;
-    uint32_t    waker_tid;
-    uint8_t     woken_kind;
-    uint8_t     waker_kind;
-    uint8_t     reserved[2];
-    char        woken_name[TASK_NAME_BYTES];
-    char        waker_name[TASK_NAME_BYTES];
-} __attribute__((packed));
-
-static_assert(sizeof(sched_wakeup_payload) == sizeof(trace_record::payload),
-              "sched_wakeup_payload must fill a record payload");
-
-struct syscall_payload {
-    uint64_t    duration_ns;
-    int64_t     result;
-    uint32_t    number;
-    uint32_t    tid;
-    uint32_t    pid;
-    uint8_t     reserved[20];
-} __attribute__((packed));
-
-static_assert(sizeof(syscall_payload) == sizeof(trace_record::payload),
-              "syscall_payload must fill a record payload");
-
-struct page_fault_payload {
-    uint64_t    address;
-    uint64_t    flags;
-    uint64_t    duration_ns;
-    int32_t     result;
-    uint32_t    tid;
-    uint8_t     reserved[16];
-} __attribute__((packed));
-
-static_assert(sizeof(page_fault_payload) == sizeof(trace_record::payload),
-              "page_fault_payload must fill a record payload");
-
 #if defined(KTRACE_ENABLED) && KTRACE_ENABLED == 1
     /**
     * @brief Records this CPU switching from task `prev` to `next` when the session