From 7579d48b61ca17f7114b517ab88aabf30c99b64d Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Thu, 4 Apr 2024 15:34:37 +0900 Subject: [PATCH v3 1/2] Add "Backpatch" regions in wait_event_names.txt When backpatching, adding an event will renumber others, which can make an extension report the wrong event until recompiled. This is due to the fact that generate-wait_event_types.pl sorts events to position them. The "Backpatch" region added here ensures no ordering is done for the wait events found after this delimiter. --- .../activity/generate-wait_event_types.pl | 27 ++++++++++++++++++- .../utils/activity/wait_event_names.txt | 20 +++++++++++++- 2 files changed, 45 insertions(+), 2 deletions(-) diff --git a/src/backend/utils/activity/generate-wait_event_types.pl b/src/backend/utils/activity/generate-wait_event_types.pl index f1adf0e8e7..456a00b86a 100644 --- a/src/backend/utils/activity/generate-wait_event_types.pl +++ b/src/backend/utils/activity/generate-wait_event_types.pl @@ -38,7 +38,9 @@ die "Not possible to specify --docs and --code simultaneously" open my $wait_event_names, '<', $ARGV[0] or die; +my @backpatch_lines; my @lines; +my $backpatch = 0; my $section_name; my $note; my $note_name; @@ -59,10 +61,27 @@ while (<$wait_event_names>) { $section_name = $_; $section_name =~ s/^.*- //; + $backpatch = 0; next; } - push(@lines, $section_name . "\t" . $_); + # Backpatch region, preserving ABI compatibility of the code + # generated. Any wait events listed in this part of the file + # will not be sorted during the code generation. + if (/^Backpatch:$/) + { + $backpatch = 1; + next; + } + + if ($gen_code && $backpatch) + { + push(@backpatch_lines, $section_name . "\t" . $_); + } + else + { + push(@lines, $section_name . "\t" . $_); + } } # Sort the lines based on the second column. @@ -70,6 +89,12 @@ while (<$wait_event_names>) my @lines_sorted = sort { uc((split(/\t/, $a))[1]) cmp uc((split(/\t/, $b))[1]) } @lines; +# If we are generating code, concat @lines_sorted and then @backpatch_lines. +if ($gen_code) +{ + push(@lines_sorted, @backpatch_lines); +} + # Read the sorted lines and populate the hash table foreach my $line (@lines_sorted) { diff --git a/src/backend/utils/activity/wait_event_names.txt b/src/backend/utils/activity/wait_event_names.txt index 0d288d6b3d..5afa4d4839 100644 --- a/src/backend/utils/activity/wait_event_names.txt +++ b/src/backend/utils/activity/wait_event_names.txt @@ -26,6 +26,12 @@ # When adding a new wait event, make sure it is placed in the appropriate # ClassName section. # +# Wait events added in stable branches should be appended to the lists in +# the "Backpatch:" region of their related ClassName section to preserve +# ABI compatibility of the C code generated from this file's data, respecting +# the order of any wait event already listed there. The "Backpatch:" regions +# should remain empty on the master branch and on unreleased branches. +# # WaitEventLWLock and WaitEventLock have their own C code for their wait event # enums and function names. Hence, for these, only the SGML documentation is # generated. @@ -61,6 +67,7 @@ WAL_SENDER_MAIN "Waiting in main loop of WAL sender process." WAL_SUMMARIZER_WAL "Waiting in WAL summarizer for more WAL to be generated." WAL_WRITER_MAIN "Waiting in main loop of WAL writer process." +Backpatch: # # Wait Events - Client @@ -81,8 +88,10 @@ SSL_OPEN_SERVER "Waiting for SSL while attempting connection." WAIT_FOR_STANDBY_CONFIRMATION "Waiting for WAL to be received and flushed by the physical standby." WAIT_FOR_WAL_REPLAY "Waiting for a replay of the particular WAL position on the physical standby." WAL_SENDER_WAIT_FOR_WAL "Waiting for WAL to be flushed in WAL sender process." -WAL_SENDER_WRITE_DATA "Waiting for any activity when processing replies from WAL receiver in WAL sender process." +WAL_SENDER_WRITE_ZZZ "Waiting for wal sender write ZZ." +WAL_SENDER_WRITE_DATA "Waiting for wal sender write data." +Backpatch: # # Wait Events - IPC @@ -150,6 +159,7 @@ WAL_RECEIVER_WAIT_START "Waiting for startup process to send initial data for st WAL_SUMMARY_READY "Waiting for a new WAL summary to be generated." XACT_GROUP_UPDATE "Waiting for the group leader to update transaction status at end of a parallel operation." +Backpatch: # # Wait Events - Timeout @@ -170,6 +180,7 @@ VACUUM_DELAY "Waiting in a cost-based vacuum delay point." VACUUM_TRUNCATE "Waiting to acquire an exclusive lock to truncate off any empty pages at the end of a table vacuumed." WAL_SUMMARIZER_ERROR "Waiting after a WAL summarizer error." +Backpatch: # # Wait Events - IO @@ -257,6 +268,7 @@ WAL_SYNC "Waiting for a WAL file to reach durable storage." WAL_SYNC_METHOD_ASSIGN "Waiting for data to reach durable storage while assigning a new WAL sync method." WAL_WRITE "Waiting for a write to a WAL file." +Backpatch: # # Wait Events - Buffer Pin @@ -266,6 +278,7 @@ Section: ClassName - WaitEventBufferPin BUFFER_PIN "Waiting to acquire an exclusive pin on a buffer." +Backpatch: # # Wait Events - Extension @@ -275,6 +288,8 @@ Section: ClassName - WaitEventExtension Extension "Waiting in an extension." +Backpatch: + # # Wait Events - LWLock # @@ -379,6 +394,7 @@ SubtransSLRU "Waiting to access the sub-transaction SLRU cache." XactSLRU "Waiting to access the transaction status SLRU cache." ParallelVacuumDSA "Waiting for parallel vacuum dynamic shared memory allocation." +# No "Backpatch" region here as code is generated automatically. # # Wait Events - Lock @@ -401,3 +417,5 @@ object "Waiting to acquire a lock on a non-relation database object." userlock "Waiting to acquire a user lock." advisory "Waiting to acquire an advisory user lock." applytransaction "Waiting to acquire a lock on a remote transaction being applied by a logical replication subscriber." + +# No "Backpatch" region here as code is generated automatically. -- 2.43.0