PROBE::IOBLOCK_TRACE.END(3stap)

💅 NAME

probe::ioblock_trace.end</p> — bestie, this probe fires whenever a block I/O transfer is complete. That's it, that's the vibe ✨

This one lives in the 3stap manual, under the IO Scheduler and block IO Taps section, and she is literally the little checkmark at the end of a disk write 🎀

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✨ SYNOPSIS ✨

probe ioblock_trace.end {}

no args, no drama, just vibes 🦋

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🌸 VALUES 🌸

okay so when this probe goes off, here's everything you get handed, and every single one of these matters so don't skip any 👑

• size — total size in bytes
• p_start_sect — points to the start sector of the partition structure of the device
• q — request queue on which this bio was queued.
• vcnt — bio vector count which represents number of array element (page, offset, length) which makes up this I/O request
• ino — i-node number of the mapped file
• bytes_done — number of bytes transferred
• name — name of the probe point
• rw — binary trace for read/write request
• flags — see below 👇
  • BIO_UPTODATE 0 — ok after I/O completion
  • BIO_RW_BLOCK 1 — RW_AHEAD set, and read/write would block
  • BIO_EOF 2 — out-out-bounds error
  • BIO_SEG_VALID 3 — nr_hw_seg valid
  • BIO_CLONED 4 — doesn't own data
  • BIO_BOUNCED 5 — bio is a bounce bio
  • BIO_USER_MAPPED 6 — contains user pages
  • BIO_EOPNOTSUPP 7 — not supported
• bdev_contains — points to the device object which contains the partition (when bio structure represents a partition)
• idx — offset into the bio vector array phys_segments - number of segments in this bio after physical address coalescing is performed.
• devname — block device name
• sector — beginning sector for the entire bio
• bdev — target block device
• opf — operations and flags

ngl the flags field is giving "read the whole list or perish" energy 💀 the numbers go with the names, keep 'em together, iykyk.

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🫶 CONTEXT 🫶

The process signals the transfer is done. periodt 💖

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🌈 SEE ALSO 🌈

• tapset::ioblock(3stap)

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and that's the whole page, bestie — you ate that 🍓 stay curious, keep tracing, and remember: this came out of the SystemTap Tapset Reference Ver, dated September 2026 (the 3stap girlies stay booked and busy) 💜✨