aboutsummaryrefslogtreecommitdiff
path: root/src/backend
Commit message (Collapse)AuthorAge
* Fix comment in injection_point.cMichael Paquier2024-11-13
| | | | | | | | | | InjectionPointEntry->name was described as a hash key, which was fine when introduced in d86d20f0ba79, but it is not now. Oversight in 86db52a5062a, that has changed the way injection points are stored in shared memory from a hash table to an array. Backpatch-through: 17
* Fix obsolete nbtree page reuse FSM comment.Peter Geoghegan2024-11-12
| | | | Oversight in commit d088ba5a.
* Silence compilers about extractNotNullColumn()Álvaro Herrera2024-11-12
| | | | | | | | | | | | | | | Multiple buildfarm animals warn that a newly added Assert() is impossible to fail; remove it to avoid the noise. While at it, use direct assignment to obtain the value we need, avoiding an unnecessary memcpy(). (I decided to remove the "pfree" call for the detoasted short-datum; because this is only used for DDL, it's not problematic to leak such a small allocation.) Noted by Tom Lane about 14e87ffa5c54. Discussion: https://postgr.es/m/3649828.1731083171@sss.pgh.pa.us
* Fix arrays comparison in CompareOpclassOptions()Alexander Korotkov2024-11-12
| | | | | | | | | | | | | The current code calls array_eq() and does not provide FmgrInfo. This commit provides initialization of FmgrInfo and uses C collation as the safe option for text comparison because we don't know anything about the semantics of opclass options. Backpatch to 13, where opclass options were introduced. Reported-by: Nicolas Maus Discussion: https://postgr.es/m/18692-72ea398df3ec6712%40postgresql.org Backpatch-through: 13
* Parallel workers use AuthenticatedUserId for connection privilege checks.Tom Lane2024-11-11
| | | | | | | | | | | | | | | | | | | | | Commit 5a2fed911 had an unexpected side-effect: the parallel worker launched for the new test case would fail if it couldn't use a superuser-reserved connection slot. The reason that test failed while all our pre-existing ones worked is that the connection privilege tests in InitPostgres had been based on the superuserness of the leader's AuthenticatedUserId, but after the rearrangements of 5a2fed911 we were testing the superuserness of CurrentUserId, which the new test case deliberately made to be a non-superuser. This all seems very accidental and probably not the behavior we really want, but a security patch is no time to be redesigning things. Pending some discussion about desirable semantics, hack it so that InitPostgres continues to pay attention to the superuserness of AuthenticatedUserId when starting a parallel worker. Nathan Bossart and Tom Lane, per buildfarm member sawshark. Security: CVE-2024-10978
* Fix improper interactions between session_authorization and role.Tom Lane2024-11-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The SQL spec mandates that SET SESSION AUTHORIZATION implies SET ROLE NONE. We tried to implement that within the lowest-level functions that manipulate these settings, but that was a bad idea. In particular, guc.c assumes that it doesn't matter in what order it applies GUC variable updates, but that was not the case for these two variables. This problem, compounded by some hackish attempts to work around it, led to some security-grade issues: * Rolling back a transaction that had done SET SESSION AUTHORIZATION would revert to SET ROLE NONE, even if that had not been the previous state, so that the effective user ID might now be different from what it had been. * The same for SET SESSION AUTHORIZATION in a function SET clause. * If a parallel worker inspected current_setting('role'), it saw "none" even when it should see something else. Also, although the parallel worker startup code intended to cope with the current role's pg_authid row having disappeared, its implementation of that was incomplete so it would still fail. Fix by fully separating the miscinit.c functions that assign session_authorization from those that assign role. To implement the spec's requirement, teach set_config_option itself to perform "SET ROLE NONE" when it sets session_authorization. (This is undoubtedly ugly, but the alternatives seem worse. In particular, there's no way to do it within assign_session_authorization without incompatible changes in the API for GUC assign hooks.) Also, improve ParallelWorkerMain to directly set all the relevant user-ID variables instead of relying on some of them to get set indirectly. That allows us to survive not finding the pg_authid row during worker startup. In v16 and earlier, this includes back-patching 9987a7bf3 which fixed a violation of GUC coding rules: SetSessionAuthorization is not an appropriate place to be throwing errors from. Security: CVE-2024-10978
* Ensure cached plans are correctly marked as dependent on role.Nathan Bossart2024-11-11
| | | | | | | | | | | | | | If a CTE, subquery, sublink, security invoker view, or coercion projection references a table with row-level security policies, we neglected to mark the plan as potentially dependent on which role is executing it. This could lead to later executions in the same session returning or hiding rows that should have been hidden or returned instead. Reported-by: Wolfgang Walther Reviewed-by: Noah Misch Security: CVE-2024-10976 Backpatch-through: 12
* Add two attributes to pg_stat_database for parallel workers activityMichael Paquier2024-11-11
| | | | | | | | | | | | | | | | | | | | | | Two attributes are added to pg_stat_database: * parallel_workers_to_launch, counting the total number of parallel workers that were planned to be launched. * parallel_workers_launched, counting the total number of parallel workers actually launched. The ratio of both fields can provide hints that there are not enough slots available when launching parallel workers, also useful when pg_stat_statements is not deployed on an instance (i.e. cf54a2c00254). This commit relies on de3a2ea3b264, that has added two fields to EState, that get incremented when executing Gather or GatherMerge nodes. A test is added in select_parallel, where parallel workers are spawned. Bump catalog version. Author: Benoit Lobréau Discussion: https://postgr.es/m/783bc7f7-659a-42fa-99dd-ee0565644e25@dalibo.com
* Assert consistency of currPage that ended scan.Peter Geoghegan2024-11-08
| | | | | | | | | | | | | | | | | When _bt_readnextpage is called with our nbtree parallel scan already seized (i.e. when it is directly called by _bt_first), we never expect a prior call to _bt_readpage for lastcurrblkno to already indicate that the scan should end -- the _bt_first caller's blkno must always be read. After all, the "prior" _bt_readpage call (the call for lastcurrblkno) probably took place in some other backend (and it might not even have finished by the time our backend reaches _bt_first/_bt_readnextpage). Add a documenting assertion to the path where _bt_readnextpage ends the parallel scan based on information about lastcurrblkno from so->currPos. Assert that the most recent _bt_readpage call that set so->currPos is in fact lastcurrblkno's _bt_readpage call. Follow-up to bugfix commit b5ee4e52.
* Improve fix for not entering parallel mode when holding interrupts.Tom Lane2024-11-08
| | | | | | | | | | | | | | | | | | | | | | | Commit ac04aa84a put the shutoff for this into the planner, which is not ideal because it doesn't prevent us from re-using a previously made parallel plan. Revert the planner change and instead put the shutoff into InitializeParallelDSM, modeling it on the existing code there for recovering from failure to allocate a DSM segment. However, that code path is mostly untested, and testing a bit harder showed there's at least one bug: ExecHashJoinReInitializeDSM is not prepared for us to have skipped doing parallel DSM setup. I also thought the Assert in ReinitializeParallelWorkers is pretty ill-advised, and replaced it with a silent Min() operation. The existing test case added by ac04aa84a serves fine to test this version of the fix, so no change needed there. Patch by me, but thanks to Noah Misch for the core idea that we could shut off worker creation when !INTERRUPTS_CAN_BE_PROCESSED. Back-patch to v12, as ac04aa84a was. Discussion: https://postgr.es/m/CAC-SaSzHUKT=vZJ8MPxYdC_URPfax+yoA1hKTcF4ROz_Q6z0_Q@mail.gmail.com
* Avoid nbtree parallel scan currPos confusion.Peter Geoghegan2024-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 1bd4bc85, which refactored nbtree sibling link traversal, made _bt_parallel_seize reset the scan's currPos so that things were consistent with the state of a serial backend moving between pages. This overlooked the fact that _bt_readnextpage relied on the existing currPos state to decide when to end the scan -- even though it came from before the scan was seized. As a result of all this, parallel nbtree scans could needlessly behave like full index scans. To fix, teach _bt_readnextpage to explicitly allow the use of an already read page's so->currPos when deciding whether to end the scan -- even during parallel index scans (allow it consistently now). This requires moving _bt_readnextpage's seizure of the scan to earlier in its loop. That way _bt_readnextpage either deals with the true so->currPos state, or an initialized-by-_bt_parallel_seize currPos state set from when the scan was seized. Now _bt_steppage (the most important _bt_readnextpage caller) takes the same uniform approach to setting up its call using details taken from so->currPos -- regardless of whether the scan happens to be parallel or serial. The new loop structure in _bt_readnextpage is prone to getting confused by P_NONE blknos set when the rightmost or leftmost page was reached. We could avoid that by adding an explicit check, but that would be ugly. Avoid this problem by teaching _bt_parallel_seize to end the parallel scan instead of returning a P_NONE next block/blkno. Doing things this way was arguably a missed opportunity for commit 1bd4bc85. It allows us to remove a similar "blkno == P_NONE" check from _bt_first. Oversight in commit 1bd4bc85, which refactored sibling link traversal (as part of optimizing nbtree backward scan locking). Author: Peter Geoghegan <pg@bowt.ie> Reported-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com> Diagnosed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com> Reviewed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com> Discussion: https://postgr.es/m/f8efb9c0f8d1a71b44fd7f8e42e49c25@oss.nttdata.com
* Add pg_constraint rows for not-null constraintsÁlvaro Herrera2024-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We now create contype='n' pg_constraint rows for not-null constraints on user tables. Only one such constraint is allowed for a column. We propagate these constraints to other tables during operations such as adding inheritance relationships, creating and attaching partitions and creating tables LIKE other tables. These related constraints mostly follow the well-known rules of conislocal and coninhcount that we have for CHECK constraints, with some adaptations: for example, as opposed to CHECK constraints, we don't match not-null ones by name when descending a hierarchy to alter or remove it, instead matching by the name of the column that they apply to. This means we don't require the constraint names to be identical across a hierarchy. The inheritance status of these constraints can be controlled: now we can be sure that if a parent table has one, then all children will have it as well. They can optionally be marked NO INHERIT, and then children are free not to have one. (There's currently no support for altering a NO INHERIT constraint into inheriting down the hierarchy, but that's a desirable future feature.) This also opens the door for having these constraints be marked NOT VALID, as well as allowing UNIQUE+NOT NULL to be used for functional dependency determination, as envisioned by commit e49ae8d3bc58. It's likely possible to allow DEFERRABLE constraints as followup work, as well. psql shows these constraints in \d+, though we may want to reconsider if this turns out to be too noisy. Earlier versions of this patch hid constraints that were on the same columns of the primary key, but I'm not sure that that's very useful. If clutter is a problem, we might be better off inventing a new \d++ command and not showing the constraints in \d+. For now, we omit these constraints on system catalog columns, because they're unlikely to achieve anything. The main difference to the previous attempt at this (b0e96f311985) is that we now require that such a constraint always exists when a primary key is in the column; we didn't require this previously which had a number of unpalatable consequences. With this requirement, the code is easier to reason about. For example: - We no longer have "throwaway constraints" during pg_dump. We needed those for the case where a table had a PK without a not-null underneath, to prevent a slow scan of the data during restore of the PK creation, which was particularly problematic for pg_upgrade. - We no longer have to cope with attnotnull being set spuriously in case a primary key is dropped indirectly (e.g., via DROP COLUMN). Some bits of code in this patch were authored by Jian He. Author: Álvaro Herrera <alvherre@alvh.no-ip.org> Author: Bernd Helmle <mailings@oopsware.de> Reviewed-by: 何建 (jian he) <jian.universality@gmail.com> Reviewed-by: 王刚 (Tender Wang) <tndrwang@gmail.com> Reviewed-by: Justin Pryzby <pryzby@telsasoft.com> Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com> Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com> Discussion: https://postgr.es/m/202408310358.sdhumtyuy2ht@alvherre.pgsql
* Disallow partitionwise join when collations don't matchAmit Langote2024-11-08
| | | | | | | | | | | | | | | | If the collation of any join key column doesn’t match the collation of the corresponding partition key, partitionwise joins can yield incorrect results. For example, rows that would match under the join key collation might be located in different partitions due to the partitioning collation. In such cases, a partitionwise join would yield different results from a non-partitionwise join, so disallow it in such cases. Reported-by: Tender Wang <tndrwang@gmail.com> Author: Jian He <jian.universality@gmail.com> Reviewed-by: Tender Wang <tndrwang@gmail.com> Reviewed-by: Junwang Zhao <zhjwpku@gmail.com> Discussion: https://postgr.es/m/CAHewXNno_HKiQ6PqyLYfuqDtwp7KKHZiH1J7Pqyz0nr+PS2Dwg@mail.gmail.com Backpatch-through: 12
* Disallow partitionwise grouping when collations don't matchAmit Langote2024-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the collation of any grouping column doesn’t match the collation of the corresponding partition key, partitionwise grouping can yield incorrect results. For example, rows that would be grouped under the grouping collation may end up in different partitions under the partitioning collation. In such cases, full partitionwise grouping would produce results that differ from those without partitionwise grouping, so disallowed that. Partial partitionwise aggregation is still allowed, as the Finalize step reconciles partition-level aggregates with grouping requirements across all partitions, ensuring that the final output remains consistent. This commit also fixes group_by_has_partkey() by ensuring the RelabelType node is stripped from grouping expressions when matching them to partition key expressions to avoid false mismatches. Bug: #18568 Reported-by: Webbo Han <1105066510@qq.com> Author: Webbo Han <1105066510@qq.com> Reviewed-by: Tender Wang <tndrwang@gmail.com> Reviewed-by: Aleksander Alekseev <aleksander@timescale.com> Reviewed-by: Jian He <jian.universality@gmail.com> Discussion: https://postgr.es/m/18568-2a9afb6b9f7e6ed3@postgresql.org Discussion: https://postgr.es/m/tencent_9D9103CDA420C07768349CC1DFF88465F90A@qq.com Discussion: https://postgr.es/m/CAHewXNno_HKiQ6PqyLYfuqDtwp7KKHZiH1J7Pqyz0nr+PS2Dwg@mail.gmail.com Backpatch-through: 12
* Fix inconsistent RestrictInfo serial numbersRichard Guo2024-11-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we generate multiple clones of the same qual condition to cope with outer join identity 3, we need to ensure that all the clones get the same serial number. To achieve this, we reset the root->last_rinfo_serial counter each time we produce RestrictInfo(s) from the qual list (see deconstruct_distribute_oj_quals). This approach works only if we ensure that we are not changing the qual list in any way that'd affect the number of RestrictInfos built from it. However, with b262ad440, an IS NULL qual on a NOT NULL column might result in an additional constant-FALSE RestrictInfo. And different versions of the same qual clause can lead to different conclusions about whether it can be reduced to constant-FALSE. This would affect the number of RestrictInfos built from the qual list for different versions, causing inconsistent RestrictInfo serial numbers across multiple clones of the same qual. This inconsistency can confuse users of these serial numbers, such as rebuild_joinclause_attr_needed, and lead to planner errors such as "ERROR: variable not found in subplan target lists". To fix, reset the root->last_rinfo_serial counter after generating the additional constant-FALSE RestrictInfo. Back-patch to v17 where the issue crept in. In v17, I failed to make a test case that would expose this bug, so no test case for v17. Author: Richard Guo Discussion: https://postgr.es/m/CAMbWs4-B6kafn+LmPuh-TYFwFyEm-vVj3Qqv7Yo-69CEv14rRg@mail.gmail.com
* Clarify a foreign key error messagePeter Eisentraut2024-11-07
| | | | | | | | Clarify the message about type mismatch in foreign key definition to indicate which column the referencing and which is the referenced one. Reported-by: Jian He <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/CACJufxEL82ao-aXOa=d_-Xip0bix-qdSyNc9fcWxOdkEZFko8w@mail.gmail.com
* Remove an obsolete comment in gistinsert()Michael Paquier2024-11-07
| | | | | | | | | This is inconsistent since 1f7ef548ec2e where the definition of gistFormTuple() has changed. Author: Tender Wang Reviewed-by: Aleksander Alekseev Discussion: https://postgr.es/m/CAHewXNkjU95_HdioDVU=5yBq_Xt=GfBv=Od-0oKtiA006pWW7Q@mail.gmail.com
* Replicate generated columns when 'publish_generated_columns' is set.Amit Kapila2024-11-07
| | | | | | | | | | | | | | | | | | | | This patch builds on the work done in commit 745217a051 by enabling the replication of generated columns alongside regular column changes through a new publication parameter: publish_generated_columns. Example usage: CREATE PUBLICATION pub1 FOR TABLE tab_gencol WITH (publish_generated_columns = true); The column list takes precedence. If the generated columns are specified in the column list, they will be replicated even if 'publish_generated_columns' is set to false. Conversely, if generated columns are not included in the column list (assuming the user specifies a column list), they will not be replicated even if 'publish_generated_columns' is true. Author: Vignesh C, Shubham Khanna Reviewed-by: Peter Smith, Amit Kapila, Hayato Kuroda, Shlok Kyal, Ajin Cherian, Hou Zhijie, Masahiko Sawada Discussion: https://postgr.es/m/B80D17B2-2C8E-4C7D-87F2-E5B4BE3C069E@gmail.com
* Remove unused variableDaniel Gustafsson2024-11-06
| | | | | | | | | | | The low variable has not been used since it was added in d168b666823 and can be safely removed. The variable is present in the Sedgewick paper "Analysis of Shellsort and Related Algorithms" as a parameter to the shellsort function, but our implementation does not use it. Remove to improve readability of the code. Author: Koki Nakamura <btnakamurakoukil@oss.nttdata.com> Discussion: https://postgr.es/m/8aeb7b3eda53ca4c65fbacf8f43628fb@oss.nttdata.com
* doc: Remove event trigger firing matrixPeter Eisentraut2024-11-06
| | | | | | | | | | | | | | | | This is difficult to maintain accurately, and it was probably already somewhat incorrect, especially in the sql_drop and table_rewrite categories. The prior section already documented which DDL commands are *not* supported (which was also slightly outdated), so let's expand that a bit and just rely on that instead of listing out each command in full detail. Reviewed-by: Daniel Gustafsson <daniel@yesql.se> Reviewed-by: Michael Paquier <michael@paquier.xyz> Reviewed-by: Jian He <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/CACJufxE_UAuxcM08BW5oVsg34v0cFWoEt8yBa5xSAoKLmL6LTQ%40mail.gmail.com
* Monkey-patch LLVM code to fix ARM relocation bug.Thomas Munro2024-11-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Supply a new memory manager for RuntimeDyld, to avoid crashes in generated code caused by memory placement that can overflow a 32 bit data type. This is a drop-in replacement for the llvm::SectionMemoryManager class in the LLVM library, with Michael Smith's proposed fix from https://www.github.com/llvm/llvm-project/pull/71968. We hereby slurp it into our own source tree, after moving into a new namespace llvm::backport and making some minor adjustments so that it can be compiled with older LLVM versions as far back as 12. It's harder to make it work on even older LLVM versions, but it doesn't seem likely that people are really using them so that is not investigated for now. The problem could also be addressed by switching to JITLink instead of RuntimeDyld, and that is the LLVM project's recommended solution as the latter is about to be deprecated. We'll have to do that soon enough anyway, and then when the LLVM version support window advances far enough in a few years we'll be able to delete this code. Unfortunately that wouldn't be enough for PostgreSQL today: in most relevant versions of LLVM, JITLink is missing or incomplete. Several other projects have already back-ported this fix into their fork of LLVM, which is a vote of confidence despite the lack of commit into LLVM as of today. We don't have our own copy of LLVM so we can't do exactly what they've done; instead we have a copy of the whole patched class so we can pass an instance of it to RuntimeDyld. The LLVM project hasn't chosen to commit the fix yet, and even if it did, it wouldn't be back-ported into the releases of LLVM that most of our users care about, so there is not much point in waiting any longer for that. If they make further changes and commit it to LLVM 19 or 20, we'll still need this for older versions, but we may want to resynchronize our copy and update some comments. The changes that we've had to make to our copy can be seen by diffing our SectionMemoryManager.{h,cpp} files against the ones in the tree of the pull request. Per the LLVM project's license requirements, a copy is in SectionMemoryManager.LICENSE. This should fix the spate of crash reports we've been receiving lately from users on large memory ARM systems. Back-patch to all supported releases. Co-authored-by: Thomas Munro <thomas.munro@gmail.com> Co-authored-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> Reviewed-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> Reviewed-by: Daniel Gustafsson <daniel@yesql.se> (license aspects) Reported-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com> Discussion: https://postgr.es/m/CAO6_Xqr63qj%3DSx7HY6ZiiQ6R_JbX%2B-p6sTPwDYwTWZjUmjsYBg%40mail.gmail.com
* Fix hypothetical bug in ExprState building for hashingDavid Rowley2024-11-06
| | | | | | | | | | | | | | | | | | | adf97c156 gave ExprStates the ability to hash expressions and return a single hash value. That commit supports seeding the hash value with an initial value to have that blended into the final hash value. Here we fix a hypothetical bug where if there are zero expressions to hash, the initial value is stored in the wrong location. The existing code stored the initial value in an intermediate location expecting that when the expressions were hashed that those steps would store the final hash value in the ExprState.resvalue field. However, that wouldn't happen when there are zero expressions to hash. The correct thing to do instead is to have a special case for zero expressions and when we hit that case, store the initial value directly in the ExprState.resvalue. The reason that this is a hypothetical bug is that no code currently calls ExecBuildHash32Expr passing a non-zero initial value. Discussion: https://postgr.es/m/CAApHDvpMAL_zxbMRr1LOex3O7Y7R7ZN2i8iUFLQhqQiJMAg3qw@mail.gmail.com
* Clear padding of PgStat_HashKey when handling pgstats entriesMichael Paquier2024-11-05
| | | | | | | | | | | | | | | | | | PgStat_HashKey is currently initialized in a way that could result in random data if the structure has any padding bytes. The structure has no padding bytes currently, fortunately, but it could become a problem should the structure change at some point in the future. The code is changed to use some memset(0) so as any padding would be handled properly, as it would be surprising to see random failures in the pgstats entry lookups. PgStat_HashKey is a structure internal to pgstats, and an ABI change could be possible in the scope of a bug fix, so backpatch down to 15 where this has been introduced. Author: Bertrand Drouvot Reviewed-by: Jelte Fennema-Nio, Michael Paquier Discussion: https://postgr.es/m/Zyb7RW1y9dVfO0UH@ip-10-97-1-34.eu-west-3.compute.internal Backpatch-through: 15
* Revert pg_wal_replay_wait() stored procedureAlexander Korotkov2024-11-04
| | | | | | | | | | | | | | | | This commit reverts 3c5db1d6b0, and subsequent improvements and fixes including 8036d73ae3, 867d396ccd, 3ac3ec580c, 0868d7ae70, 85b98b8d5a, 2520226c95, 014f9f34d2, e658038772, e1555645d7, 5035172e4a, 6cfebfe88b, 73da6b8d1b, and e546989a26. The reason for reverting is a set of remaining issues. Most notably, the stored procedure appears to need more effort than the utility statement to turn the backend into a "snapshot-less" state. This makes an approach to use stored procedures questionable. Catversion is bumped. Discussion: https://postgr.es/m/Zyhj2anOPRKtb0xW%40paquier.xyz
* Fix typo in comment of gistdoinsert().Masahiko Sawada2024-11-04
| | | | | | Author: Tender Wang Reviewed-by: Masahiko Sawada Discussion: https://postgr.es/m/CAHewXN%3D3sH2sNw4nC3QGCEVw1Lftmw9m5y1Xje0bXK6ApDrsPQ%40mail.gmail.com
* Fix obsolete _bt_first comments.Peter Geoghegan2024-11-04
| | | | | | | _bt_first doesn't necessarily hold onto a buffer pin on success exit. Fix header comments that claimed that we'll always hold onto a pin. Oversight in commit 2ed5b87f96.
* nbtree: Remove useless 'strat' local variable.Peter Geoghegan2024-11-04
| | | | | | | | | | | | | | | | | | | | | Remove a local variable that was used to avoid overwriting strat_total with the = operator strategy when a >= operator strategy key was already included in the initial positioning/insertion scan keys by _bt_first (for backwards scans it would have to be a <= key that was included). _bt_first's strat_total local variable now simply tracks the operator strategy of the final scan key that was included in the scan's insertion scan key (barring the case where the !used_all_subkeys row compare path adjusts strat_total in its own way). _bt_first already treated >= keys (or <= keys) as = keys for initial positioning purposes. There is no good reason to remember that that was what happened; no later _bt_first step cares about the distinction. Note, in particular, that the insertion scan key's 'nextkey' and 'backward' fields will be initialized the same way regardless. Author: Peter Geoghegan <pg@bowt.ie> Reviewed-By: Tomas Vondra <tomas@vondra.me> Discussion: https://postgr.es/m/CAH2-Wz=PKR6rB7qbx+Vnd7eqeB5VTcrW=iJvAsTsKbdG+kW_UA@mail.gmail.com
* Split ProcSleep function into JoinWaitQueue and ProcSleepHeikki Linnakangas2024-11-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Split ProcSleep into two functions: JoinWaitQueue and ProcSleep. JoinWaitQueue is called while holding the partition lock, and inserts the current process to the wait queue, while ProcSleep() does the actual sleeping. ProcSleep() is now called without holding the partition lock, and it no longer re-acquires the partition lock before returning. That makes the wakeup a little cheaper. Once upon a time, re-acquiring the partition lock was needed to prevent a signal handler from longjmping out at a bad time, but these days our signal handlers just set flags, and longjmping can only happen at points where we explicitly run CHECK_FOR_INTERRUPTS(). If JoinWaitQueue detects an "early deadlock" before even joining the wait queue, it returns without changing the shared lock entry, leaving the cleanup of the shared lock entry to the caller. This makes the handling of an early deadlock the same as the dontWait=true case. One small user-visible side-effect of this refactoring is that we now only set the 'ps' title to say "waiting" when we actually enter the sleep, not when the lock is skipped because dontWait=true, or when a deadlock is detected early before entering the sleep. This eliminates the 'lockAwaited' global variable in proc.c, which was largely redundant with 'awaitedLock' in lock.c Note: Updating the local lock table is now the caller's responsibility. JoinWaitQueue and ProcSleep are now only responsible for modifying the shared state. Seems a little nicer that way. Based on Thomas Munro's earlier patch and observation that ProcSleep doesn't really need to re-acquire the partition lock. Reviewed-by: Maxim Orlov Discussion: https://www.postgresql.org/message-id/7c2090cd-a72a-4e34-afaa-6dd2ef31440e@iki.fi
* Move TRACE calls into WaitOnLock()Heikki Linnakangas2024-11-04
| | | | | | | | LockAcquire is a long and complex function. Pushing more stuff to its subroutines makes it a little more manageable. Reviewed-by: Maxim Orlov Discussion: https://www.postgresql.org/message-id/7c2090cd-a72a-4e34-afaa-6dd2ef31440e@iki.fi
* Set MyProc->heldLocks in ProcSleepHeikki Linnakangas2024-11-04
| | | | | | | | | | | | Previously, ProcSleep()'s caller was responsible for setting MyProc->heldLocks, and we had comments to remind about that. But it seems simpler to make ProcSleep() itself responsible for it. ProcSleep() already set the other info about the lock its waiting for (waitLock, waitProcLock and waitLockMode), so it is natural for it to set heldLocks too. Reviewed-by: Maxim Orlov Discussion: https://www.postgresql.org/message-id/7c2090cd-a72a-4e34-afaa-6dd2ef31440e@iki.fi
* Clarify nbtree parallel scan _bt_endpoint contract.Peter Geoghegan2024-11-04
| | | | | | | | | | | | | | | _bt_endpoint is a helper function for _bt_first that's called whenever no useful insertion scan key can be used, and we need to lock and read either the leftmost or rightmost leaf page in the index. Simplify and document its preconditions, relieving its _bt_first caller from having to end the parallel scan when it returns false. Also stop unnecessarily invalidating the current scan position in nearby code in both _bt_first and _bt_endpoint. This seems to have been copy-pasted from _bt_readnextpage, where invalidating the scan's current position really is necessary. Follow-up to the refactoring work in commit 1bd4bc85.
* Fix comment in LockReleaseAll() on when locallock->nLock can be zeroHeikki Linnakangas2024-11-04
| | | | | | | | We reach this case also e.g. when a deadlock is detected, not only when we run out of memory. Reviewed-by: Maxim Orlov Discussion: https://www.postgresql.org/message-id/7c2090cd-a72a-4e34-afaa-6dd2ef31440e@iki.fi
* Suppress new "may be used uninitialized" warning.Noah Misch2024-11-02
| | | | | | Buildfarm member mamba fails to deduce that the function never uses this variable without initializing it. Back-patch to v12, like commit b412f402d1e020c5dac94f3bf4a005db69519b99.
* Fix inplace update buffer self-deadlock.Noah Misch2024-11-02
| | | | | | | | | | | | | | | A CacheInvalidateHeapTuple* callee might call CatalogCacheInitializeCache(), which needs a relcache entry. Acquiring a valid relcache entry might scan pg_class. Hence, to prevent undetected LWLock self-deadlock, CacheInvalidateHeapTuple* callers must not hold BUFFER_LOCK_EXCLUSIVE on buffers of pg_class. Move the CacheInvalidateHeapTupleInplace() before the BUFFER_LOCK_EXCLUSIVE. No back-patch, since I've reverted commit 243e9b40f1b2dd09d6e5bf91ebf6e822a2cd3704 from non-master branches. Reported by Alexander Lakhin. Reviewed by Alexander Lakhin. Discussion: https://postgr.es/m/10ec0bc3-5933-1189-6bb8-5dec4114558e@gmail.com
* Move I/O before the index_update_stats() buffer lock region.Noah Misch2024-11-02
| | | | | | | | | | | Commit a07e03fd8fa7daf4d1356f7cb501ffe784ea6257 enlarged the work done here under the pg_class heap buffer lock. Two preexisting actions are best done before holding that lock. Both RelationGetNumberOfBlocks() and visibilitymap_count() do I/O, and the latter might exclusive-lock a visibility map buffer. Moving these reduces contention and risk of undetected LWLock deadlock. Back-patch to v12, like that commit. Discussion: https://postgr.es/m/20241031200139.b4@rfd.leadboat.com
* Clarify nbtree array preprocessing comment.Peter Geoghegan2024-11-01
| | | | Oversight in commit 5bf748b8.
* Rename two functions that wake up other processesHeikki Linnakangas2024-11-01
| | | | | | | | | | | Instead of talking about setting latches, which is a pretty low-level mechanism, emphasize that they wake up other processes. This is in preparation for replacing Latches with a new abstraction. That's still work in progress, but this seems a little tidier anyway, so let's get this refactoring out of the way already. Discussion: https://www.postgresql.org/message-id/391abe21-413e-4d91-a650-b663af49500c%40iki.fi
* Use ProcNumbers instead of direct Latch pointers to address other procsHeikki Linnakangas2024-11-01
| | | | | | | | This is in preparation for replacing Latches with a new abstraction. That's still work in progress, but this seems a little tidier anyway, so let's get this refactoring out of the way already. Discussion: https://www.postgresql.org/message-id/391abe21-413e-4d91-a650-b663af49500c%40iki.fi
* Remove use of pg_memory_is_all_zeros() in bufpage.cMichael Paquier2024-11-01
| | | | | | | | | | | | | After a closer lookup, this makes the all-zero check of the page more expensive, so let's remove the new function call in bufpage.c. The maths of the check were also incorrect, checking that the page was full of zeros only for the first 1kB. This brings back the code to the state it was at 49d6c7d8daba. Per discussion with David Rowley and Bertrand Drouvot. Discussion: https://postgr.es/m/CAApHDvrXzPAr3FxoBuB7b3D-okNoNA2jxLun1rW8Yw5wkbqusw@mail.gmail.com
* Add pg_memory_is_all_zeros() in memutils.hMichael Paquier2024-11-01
| | | | | | | | | | | | | | | | | This new function tests if a memory region starting at a given location for a defined length is made only of zeroes. This unifies in a single path the all-zero checks that were happening in a couple of places of the backend code: - For pgstats entries of relation, checkpointer and bgwriter, where some "all_zeroes" variables were previously used with memcpy(). - For all-zero buffer pages in PageIsVerifiedExtended(). This new function uses the same forward scan as the check for all-zero buffer pages, applying it to the three pgstats paths mentioned above. Author: Bertrand Drouvot Reviewed-by: Peter Eisentraut, Heikki Linnakangas, Peter Smith Discussion: https://postgr.es/m/ZupUDDyf1hHI4ibn@ip-10-97-1-34.eu-west-3.compute.internal
* Add SQL function array_reverse()Michael Paquier2024-11-01
| | | | | | | | | | | | | | | | | This function takes in input an array, and reverses the position of all its elements. This operation only affects the first dimension of the array, like array_shuffle(). The implementation structure is inspired by array_shuffle(), with a subroutine called array_reverse_n() that may come in handy in the future, should more functions able to reverse portions of arrays be introduced. Bump catalog version. Author: Aleksander Alekseev Reviewed-by: Ashutosh Bapat, Tom Lane, Vladlen Popolitov Discussion: https://postgr.es/m/CAJ7c6TMpeO_ke+QGOaAx9xdJuxa7r=49-anMh3G5476e3CX1CA@mail.gmail.com
* Make all ereport() calls within gram.y provide error locations.Tom Lane2024-10-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch responds to a comment that I (tgl) made in the discussion leading up to 774171c4f, that really all errors occurring during raw parsing should provide error cursors. Syntax errors reported by Bison will have one, and most of the handwritten ereport's in gram.y already provide one, but there were a few stragglers. (It is not claimed that this handles every failure reachable during raw parsing --- out-of-memory is an obvious exception. But this makes a good start on cases that are likely to occur.) While we're at it, clean up the reported positions for errors associated with LIMIT/OFFSET clauses. Previously we were relying on applying exprLocation() to the contained expressions, but that leads to slightly odd cursor placement, e.g. regression=# (select * from foo limit 10) limit 10; ERROR: multiple LIMIT clauses not allowed LINE 1: (select * from foo limit 10) limit 10; ^ We can afford to keep a little more state in the transient SelectLimit structs in order to make that better. Jian He and Tom Lane (extracted from a larger patch by Jian, with some additional work by me) Discussion: https://postgr.es/m/CACJufxEmONE3P2En=jopZy1m=cCCUs65M4+1o52MW5og9oaUPA@mail.gmail.com
* Add a parse location field to struct FunctionParameter.Tom Lane2024-10-31
| | | | | | | | | | | | | | | | This allows an error cursor to be supplied for a bunch of bad-function-definition errors that previously lacked one, or that cheated a bit by pointing at the contained type name when the error isn't really about that. Bump catversion from an abundance of caution --- I don't think this node type can actually appear in stored views/rules, but better safe than sorry. Jian He and Tom Lane (extracted from a larger patch by Jian, with some additional work by me) Discussion: https://postgr.es/m/CACJufxEmONE3P2En=jopZy1m=cCCUs65M4+1o52MW5og9oaUPA@mail.gmail.com
* Fix refreshing physical relfilenumber on shared indexHeikki Linnakangas2024-10-31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Buildfarm member 'prion', which is configured with -DRELCACHE_FORCE_RELEASE -DCATCACHE_FORCE_RELEASE, failed with errors like this: ERROR: could not read blocks 0..0 in file "global/2672": read only 0 of 8192 bytes while running a parallel test group that includes VACUUM FULL on some catalog tables among other things. I was not able to reproduce that just by running the tests with -DRELCACHE_FORCE_RELEASE -DCATCACHE_FORCE_RELEASE, even though 'prion' hit it on first run after commit 2b9b8ebbf8, so there might be something else that makes it more susceptible to the race. However, I was able to reproduce it by adding another test to the same test group that runs "vacuum full pg_database" repeatedly. The problem is that RelationReloadIndexInfo() no longer calls RelationInitPhysicalAddr() on a nailed, shared index, when an invalidation happens early during backend startup, before the critical relcaches have been built. Before commit 2b9b8ebbf8, that was done by RelationReloadNailed(), but it went missing from that path. Add it back as an explicit step. Broken by commit 2b9b8ebbf8, which refactored these functions. Discussion: https://www.postgresql.org/message-id/db876575-8f5b-4193-a538-df7e1f92d47a%40iki.fi
* Remove duplicate words in commentsDaniel Gustafsson2024-10-31
| | | | | | | | A few comments contained duplicate "the" in sentences, fix by removing one occurrence. Author: Vignesh C <vignesh21@gmail.com> Discussion: https://postgr.es/m/CALDaNm2aEEiPwGJmPdzBxROVvs8n75yCjKz4K1f1B2TdWpzxTA@mail.gmail.com
* Split RelationClearRelation into three different functionsHeikki Linnakangas2024-10-31
| | | | | | | | | | | | | | | | | | | The old RelationClearRelation function did different things depending on the arguments and circumstances. It could: a) remove the relation completely from relcache (rebuild == false), b) mark the entry as invalid (rebuild == true, but not in xact), or c) rebuild the entry (rebuild == true). Different callers used it for different purposes, and often assumed a particular behavior, which was confusing. Split it into three different functions, one for each of the above actions (one of them, RelationInvalidateRelation, was already added in commit e6cd857726). Move the responsibility of choosing the action and calling the right function to the callers. Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/9c9e8908-7b3e-4ce7-85a8-00c0e165a3d6%40iki.fi
* Simplify call to rebuild relcache entry for indexesHeikki Linnakangas2024-10-31
| | | | | | | | | | | | | | | | | | RelationClearRelation(rebuild == true) calls RelationReloadIndexInfo() for indexes. We can rely on that in RelationIdGetRelation(), instead of calling RelationReloadIndexInfo() directly. That simplifies the code a little. In the passing, add a comment in RelationBuildLocalRelation() explaining why it doesn't call RelationInitIndexAccessInfo(). It's because at index creation, it's called before the pg_index row has been created. That's also the reason that RelationClearRelation() still needs a special case to go through the full-blown rebuild if the index support information in the relcache entry hasn't been populated yet. Reviewed-by: jian he <jian.universality@gmail.com> Discussion: https://www.postgresql.org/message-id/9c9e8908-7b3e-4ce7-85a8-00c0e165a3d6%40iki.fi
* Remove unused field from SubPlanState structDavid Rowley2024-10-31
| | | | | | | | | | | | | | | | bf6c614a2 did some conversion work to use ExprState instead of manually calling equality functions to check if one set of values is not distinct from another set. That patch removed many of the fields that became redundant as a result of that change, but it forgot to remove SubPlanState.tab_eq_funcs. Fix that. In passing, fix the header comment for TupleHashEntryData to correctly spell the field name it's talking about. Author: Rafia Sabih <rafia.pghackers@gmail.com> Reviewed-by: Andrei Lepikhov <lepihov@gmail.com> Discussion: https://postgr.es/m/CA+FpmFeycdombFzrjZw7Rmc29CVm4OOzCWwu=dVBQ6q=PX8SvQ@mail.gmail.com Discussion: https://postgr.es/m/CAApHDvrWR2jYVhec=COyF2g2BE_ns91NDsCHAMFiXbyhEujKdQ@mail.gmail.com
* nbtree: assert no scheduled primscan between pages.Peter Geoghegan2024-10-30
| | | | | | | | | | Follow-up to bugfix commit 763d65ae. Technically this new assertion is redundant with the assertion recently added to _bt_readpage by that same commit, but it seems like a good idea to have both. The new assertion makes it clear that we expect to call _bt_readnextpage when there's another primitive index scan scheduled, though only when needed as the final step of ending the current primitive scan.
* Clarify nbtree array exhaustion comments.Peter Geoghegan2024-10-30
| | | | | | | | | | | | | | | | Strictly speaking, we only need to make sure to leave the scan's array keys in their final positions (final for the current scan direction) to handle SAOP array exhaustion because btgettuple might only return a subset of the items for the final page (final for the current scan direction), before the scan changes direction. While it's typical for so->currPos to be invalidated shortly after the scan's arrays are first exhausted, and while so->currPos invalidation does obviate the need to leave the scan's arrays in any particular state, we can't rely on any of that actually happening when handling array exhaustion. Adjust comments to make all of that a lot clearer. Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp execution.