trace_s390_cio_tsch(9)

💅 trace_s390_cio_tsch(9) — Kernel API Manual, but make it make sense 🎀

okay bestie, so this is a page out of the Kernel API Manual, and it's about trace_s390_cio_tsch — the tracepoint you hit when a Test Subchannel instruction (TSCH) was performed. s390 vibes only, iykyk. 🦋

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✨ NAME ✨

trace_s390_cio_tsch — legit just: Test Subchannel instruction (TSCH) was performed. That's the whole gig. Iconic, lowkey, no notes. 💅

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🌸 SYNOPSIS 🌸

void trace_s390_cio_tsch (struct subchannel_id schid , struct irb *irb ,
int cc );

like yes, that's the exact signature, do not come for me about the spacing, it's verbatim bestie 🫶

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🎀 ARGUMENTS 🎀

• schid — the Subchannel ID. it's giving "which subchannel are we even talking about" energy 👑
• irb — pointer to the Interruption-Response Block. yes, the whole IRB. she's main character fr fr 🔥
• cc — the Condition code. short name, big responsibility 😭

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💜 SEE ALSO 💜

Kernel file ./drivers/s390/cio/trace.h, plus the whole cio tracepoint friend group — they all show up together, no cap:

• trace_s390_cio_stsch(9)
• trace_s390_cio_msch(9)
• trace_s390_cio_tpi(9)
• trace_s390_cio_ssch(9)
• trace_s390_cio_csch(9)
• trace_s390_cio_hsch(9)
• trace_s390_cio_xsch(9)
• trace_s390_cio_rsch(9)
• trace_s390_cio_chsc(9)
• trace_s390_cio_interrupt(9)
• trace_s390_cio_adapter_int(9)
• trace_s390_cio_stcrw(9)

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ngl there's not a ton of lore on this page — it's a tracepoint doc, so it does exactly what it says and nothing else. no warnings, no bugs section, no exit statuses, just vibes and a function signature. 🧚

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and that's the whole page, bestie! ✨ this one came from ./drivers/s390/cio, dated October 2026 — so mark your calendar, she's from the future 💀🎀 stay slay, keep your condition codes checked, mwah 💖