From a4a67e08ff1c72fefb23d2fd22f2afb5efab358f Mon Sep 17 00:00:00 2001 From: Andrey Rachitskiy Date: Wed, 29 Jul 2026 21:04:53 +0500 Subject: [PATCH] Fix SystemTap dtrace warning for smgr probe argument types Commits ca326e903d and 1f8c504e308 widened the byte-count arguments of smgr__md__read__done and smgr__md__write__done to "long long int". SystemTap's dtrace(1) fails on that specific spelling and falls back with a warning (misreported near the previous probe). Use ssize_t and size_t instead, matching the md.c call sites. Revise the probes.d note: prefer system-supplied type names (macOS dtrace rejects names like PostgreSQL's uint64), and call out "long long int" as a known SystemTap failure rather than a blanket multi-word ban. Author: Andrey Rachitskiy Reported-by: Laurenz Albe Discussion: https://postgr.es/m/697d3c88568442cd637d8453d129f1bb14bbd2a8.camel@cybertec.at --- doc/src/sgml/monitoring.sgml | 4 ++-- src/backend/utils/probes.d | 11 +++++++---- 2 files changed, 9 insertions(+), 6 deletions(-) diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml index 074a821a68e..0c7107d400b 100644 --- a/doc/src/sgml/monitoring.sgml +++ b/doc/src/sgml/monitoring.sgml @@ -8595,7 +8595,7 @@ FROM pg_stat_get_backend_idset() AS backendid; smgr-md-read-done - (ForkNumber, BlockNumber, Oid, Oid, Oid, int, int, int) + (ForkNumber, BlockNumber, Oid, Oid, Oid, int, ssize_t, size_t) Probe that fires when a block read is complete. arg0 and arg1 contain the fork and block numbers of the page. arg2, arg3, and arg4 contain the tablespace, database, and relation OIDs @@ -8617,7 +8617,7 @@ FROM pg_stat_get_backend_idset() AS backendid; smgr-md-write-done - (ForkNumber, BlockNumber, Oid, Oid, Oid, int, int, int) + (ForkNumber, BlockNumber, Oid, Oid, Oid, int, ssize_t, size_t) Probe that fires when a block write is complete. arg0 and arg1 contain the fork and block numbers of the page. arg2, arg3, and arg4 contain the tablespace, database, and relation OIDs diff --git a/src/backend/utils/probes.d b/src/backend/utils/probes.d index 2d8f12cbe30..b8a381d2f68 100644 --- a/src/backend/utils/probes.d +++ b/src/backend/utils/probes.d @@ -11,8 +11,11 @@ /* * Typedefs used in PostgreSQL probes. * - * NOTE: Do not use system-provided typedefs (e.g. uintptr_t, uint32_t, etc) - * in probe definitions, as they cause compilation errors on macOS. + * NOTE: Prefer system-supplied type names in probe definitions (e.g. + * uint64_t, not PostgreSQL's uint64); macOS' dtrace rejects the latter. + * Also avoid "long long int", as SystemTap's dtrace(1) fails on that + * specific spelling. PG type aliases below must be #define'd so that + * cpp expands them before dtrace sees the file. */ #define LocalTransactionId unsigned int #define LWLockMode int @@ -83,9 +86,9 @@ provider postgresql { probe twophase__checkpoint__done(); probe smgr__md__read__start(ForkNumber, BlockNumber, Oid, Oid, Oid, int); - probe smgr__md__read__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, long long int, long long int); + probe smgr__md__read__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, ssize_t, size_t); probe smgr__md__write__start(ForkNumber, BlockNumber, Oid, Oid, Oid, int); - probe smgr__md__write__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, long long int, long long int); + probe smgr__md__write__done(ForkNumber, BlockNumber, Oid, Oid, Oid, int, ssize_t, size_t); probe wal__insert(unsigned char, unsigned char); probe wal__switch(); -- 2.53.0