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From: Norbert Lange via lttng-dev <lttng-dev@lists.lttng.org>
To: lttng-dev <lttng-dev@lists.lttng.org>
Subject: Method to get LTTNG-UST version during runtime?
Date: Wed, 18 Jun 2025 17:22:16 +0200	[thread overview]
Message-ID: <CADYdroMBu0gocZXpeaMWqr3TG4p5FW71eeN1+y-XM_8bDxijzw@mail.gmail.com> (raw)

Hi,

there are some substantial changes in 2.14.0 that afffect how/if
tracing is possible.
For ex. c246521ddcba1d1d28cfa0482aa500b9122e7264 allows doing more work upfront
by calling lttng_ust_init_thread().
With 2.13.x the same code will instead do various syscalls or
allocations during the first tracepoints, violating realtime
constraints and possible abort the process.

I miss an easy method to inspect the Lttng UST Version for checks or
workarounds.

There is the lttng_ust_loaded variable that could be abused to carry
an packed version instead of 1. (Of course that could always cause
fallout)

Regards, Norbert

             reply	other threads:[~2025-06-18 15:22 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-18 15:22 Norbert Lange via lttng-dev [this message]
2025-06-23 14:21 ` Kienan Stewart via lttng-dev
2025-06-23 19:04   ` Norbert Lange via lttng-dev
2025-06-25 21:15     ` Kienan Stewart via lttng-dev

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