Add an xtask for listing all USDT probes in Omicron

[bnaecker]

No description provided.

[leftwo]

Why do you want this?
(Because, maybe I'll do it for Crucible too)

[ahl]

Looks good; can you post an example of its output and/or use?

[bnaecker]

@ahl Yep, here's an example, using a simple filter:

bnaecker@shale : ~/omicron $ cargo xtask probes om
   Compiling xtask v0.1.0 (/home/bnaecker/omicron/dev-tools/xtask)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.50s
     Running `target/debug/xtask probes om`
 BINARY       PROVIDER           PROBE                       ARGUMENTS
 omicron-dev  clickhouse_client  oxql-query-done             [uint64_t,char*]
 omicron-dev  clickhouse_client  oxql-query-start            [uint64_t,char*,char*]
 omicron-dev  clickhouse_client  oxql-table-op-done          [uint64_t,char*]
 omicron-dev  clickhouse_client  oxql-table-op-start         [uint64_t,char*,char*]
 omicron-dev  clickhouse_client  sql-query-done              [uint64_t]
 omicron-dev  clickhouse_client  sql-query-start             [uint64_t,char*]
 omicron-dev  diesel_db          connection-establish-done   [uint64_t,char*,uint8_t]
 omicron-dev  diesel_db          connection-establish-start  [uint64_t,char*,char*]
 omicron-dev  diesel_db          query-done                  [uint64_t,char*]
 omicron-dev  diesel_db          query-start                 [uint64_t,char*,char*]
 omicron-dev  dropshot           request-done                [char*]
 omicron-dev  dropshot           request-start               [char*]
 omicron-dev  nexus_db_queries   vni-search-range-empty      [uint64_t]
 omicron-dev  nexus_db_queries   vni-search-range-found      [uint64_t,uint32_t]
 omicron-dev  nexus_db_queries   vni-search-range-start      [uint64_t,uint32_t,uint32_t]
 omicron-dev  slog               critical                    [char*]
 omicron-dev  slog               debug                       [char*]
 omicron-dev  slog               error                       [char*]
 omicron-dev  slog               info                        [char*]
 omicron-dev  slog               trace                       [char*]
 omicron-dev  slog               warn                        [char*]
 omdb         diesel_db          connection-establish-done   [uint64_t,char*,uint8_t]
 omdb         diesel_db          connection-establish-start  [uint64_t,char*,char*]
 omdb         diesel_db          query-done                  [uint64_t,char*]
 omdb         diesel_db          query-start                 [uint64_t,char*,char*]

@leftwo Justin and I talked about this a while ago. It's mostly for visibility, to know what probes are available during debugging. I had the PR laying around, so getting into mergeable status was mostly bringing it up to date with main.

[ahl]

Really cool!