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2025-01-01Update copyright for 2025Bruce Momjian
Backpatch-through: 13
2024-07-30Remove --disable-spinlocks.Thomas Munro
A later change will require atomic support, so it wouldn't make sense for a hypothetical new system not to be able to implement spinlocks. Reviewed-by: Heikki Linnakangas <[email protected]> Reviewed-by: Tom Lane <[email protected]> (concept, not the patch) Reviewed-by: Andres Freund <[email protected]> (concept, not the patch) Discussion: https://postgr.es/m/3351991.1697728588%40sss.pgh.pa.us
2024-01-04Update copyright for 2024Bruce Momjian
Reported-by: Michael Paquier Discussion: https://postgr.es/m/[email protected] Backpatch-through: 12
2023-01-02Update copyright for 2023Bruce Momjian
Backpatch-through: 11
2022-04-08Apply PGDLLIMPORT markings broadly.Robert Haas
Up until now, we've had a policy of only marking certain variables in the PostgreSQL header files with PGDLLIMPORT, but now we've decided to mark them all. This means that extensions running on Windows should no longer operate at a disadvantage as compared to extensions running on Linux: if the variable is present in a header file, it should be accessible. Discussion: http://postgr.es/m/CA+TgmoYanc1_FSfimhgiWSqVyP5KKmh5NP2BWNwDhO8Pg2vGYQ@mail.gmail.com
2022-01-08Update copyright for 2022Bruce Momjian
Backpatch-through: 10
2021-01-02Update copyright for 2021Bruce Momjian
Backpatch-through: 9.5
2020-01-01Update copyrights for 2020Bruce Momjian
Backpatch-through: update all files in master, backpatch legal files through 9.4
2019-01-02Update copyright for 2019Bruce Momjian
Backpatch-through: certain files through 9.4
2018-01-03Update copyright for 2018Bruce Momjian
Backpatch-through: certain files through 9.3
2017-11-08Change TRUE/FALSE to true/falsePeter Eisentraut
The lower case spellings are C and C++ standard and are used in most parts of the PostgreSQL sources. The upper case spellings are only used in some files/modules. So standardize on the standard spellings. The APIs for ICU, Perl, and Windows define their own TRUE and FALSE, so those are left as is when using those APIs. In code comments, we use the lower-case spelling for the C concepts and keep the upper-case spelling for the SQL concepts. Reviewed-by: Michael Paquier <[email protected]>
2017-06-21Phase 2 of pgindent updates.Tom Lane
Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/[email protected] Discussion: https://postgr.es/m/[email protected]
2017-01-03Update copyright via script for 2017Bruce Momjian
2016-12-12Make the different Unix-y semaphore implementations ABI-compatible.Tom Lane
Previously, the "sem" field of PGPROC varied in size depending on which kernel semaphore API we were using. That was okay as long as there was only one likely choice per platform, but in the wake of commit ecb0d20a9, that assumption seems rather shaky. It doesn't seem out of the question anymore that an extension compiled against one API choice might be loaded into a postmaster built with another choice. Moreover, this prevents any possibility of selecting the semaphore API at postmaster startup, which might be something we want to do in future. Hence, change PGPROC.sem to be PGSemaphore (i.e. a pointer) for all Unix semaphore APIs, and turn the pointed-to data into an opaque struct whose contents are only known within the responsible modules. For the SysV and unnamed-POSIX APIs, the pointed-to data has to be allocated elsewhere in shared memory, which takes a little bit of rejiggering of the InitShmemAllocation code sequence. (I invented a ShmemAllocUnlocked() function to make that a little cleaner than it used to be. That function is not meant for any uses other than the ones it has now, but it beats having InitShmemAllocation() know explicitly about allocation of space for semaphores and spinlocks.) This change means an extra indirection to access the semaphore data, but since we only touch that when blocking or awakening a process, there shouldn't be any meaningful performance penalty. Moreover, at least for the unnamed-POSIX case on Linux, the sem_t type is quite a bit wider than a pointer, so this reduces sizeof(PGPROC) which seems like a good thing. For the named-POSIX API, there's effectively no change: the PGPROC.sem field was and still is a pointer to something returned by sem_open() in the postmaster's memory space. Document and check the pre-existing limitation that this case can't work in EXEC_BACKEND mode. It did not seem worth unifying the Windows semaphore ABI with the Unix cases, since there's no likelihood of needing ABI compatibility much less runtime switching across those cases. However, we can simplify the Windows code a bit if we define PGSemaphore as being directly a HANDLE, rather than pointer to HANDLE, so let's do that while we're here. (This also ends up being no change in what's physically stored in PGPROC.sem. We're just moving the HANDLE fetch from callees to callers.) It would take a bunch of additional code shuffling to get to the point of actually choosing a semaphore API at postmaster start, but the effects of that would now be localized in the port/XXX_sema.c files, so it seems like fit material for a separate patch. The need for it is unproven as yet, anyhow, whereas the ABI risk to extensions seems real enough. Discussion: https://postgr.es/m/[email protected]
2016-01-02Update copyright for 2016Bruce Momjian
Backpatch certain files through 9.1
2015-10-16Remove cautions about using volatile from spin.h.Robert Haas
Commit 0709b7ee72e4bc71ad07b7120acd117265ab51d0 obsoleted this comment but neglected to update it. Thomas Munro
2015-01-06Update copyright for 2015Bruce Momjian
Backpatch certain files through 9.0
2014-05-06pgindent run for 9.4Bruce Momjian
This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
2014-01-09We don't need to include pg_sema.h in s_lock.h anymore.Tom Lane
Minor improvement to commit daa7527afc2274432094ebe7ceb03aa41f916607: s_lock.h no longer has any need to mention PGSemaphoreData, so we can rip out the #include that supplies that. In a non-HAVE_SPINLOCKS build, this doesn't really buy much since we still need the #include in spin.h --- but everywhere else, this reduces #include footprint by some trifle, and helps keep the different locking facilities separate.
2014-01-08Reduce the number of semaphores used under --disable-spinlocks.Robert Haas
Instead of allocating a semaphore from the operating system for every spinlock, allocate a fixed number of semaphores (by default, 1024) from the operating system and multiplex all the spinlocks that get created onto them. This could self-deadlock if a process attempted to acquire more than one spinlock at a time, but since processes aren't supposed to execute anything other than short stretches of straight-line code while holding a spinlock, that shouldn't happen. One motivation for this change is that, with the introduction of dynamic shared memory, it may be desirable to create spinlocks that last for less than the lifetime of the server. Without this change, attempting to use such facilities under --disable-spinlocks would quickly exhaust any supply of available semaphores. Quite apart from that, it's desirable to contain the quantity of semaphores needed to run the server simply on convenience grounds, since using too many may make it harder to get PostgreSQL running on a new platform, which is mostly the point of --disable-spinlocks in the first place. Patch by me; review by Tom Lane.
2014-01-07Update copyright for 2014Bruce Momjian
Update all files in head, and files COPYRIGHT and legal.sgml in all back branches.
2013-01-01Update copyrights for 2013Bruce Momjian
Fully update git head, and update back branches in ./COPYRIGHT and legal.sgml files.
2012-01-01Update copyright notices for year 2012.Bruce Momjian
2011-01-01Stamp copyrights for year 2011.Bruce Momjian
2010-09-20Remove cvs keywords from all files.Magnus Hagander
2010-01-02Update copyright for the year 2010.Bruce Momjian
2009-01-01Update copyright for 2009.Bruce Momjian
2008-01-01Update copyrights in source tree to 2008.Bruce Momjian
2007-01-05Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian
back-stamped for this.
2006-03-05Update copyright for 2006. Update scripts.Bruce Momjian
2005-12-29Get rid of the SpinLockAcquire/SpinLockAcquire_NoHoldoff distinctionTom Lane
in favor of having just one set of macros that don't do HOLD/RESUME_INTERRUPTS (hence, these correspond to the old SpinLockAcquire_NoHoldoff case). Given our coding rules for spinlock use, there is no reason to allow CHECK_FOR_INTERRUPTS to be done while holding a spinlock, and also there is no situation where ImmediateInterruptOK will be true while holding a spinlock. Therefore doing HOLD/RESUME_INTERRUPTS while taking/releasing a spinlock is just a waste of cycles. Qingqing Zhou and Tom Lane.
2005-10-13Add a comment describing the requirement that pointers into shared memoryNeil Conway
that is protected by a spinlock must be volatile, per recent discussion.
2004-12-31Tag appropriate files for rc3PostgreSQL Daemon
Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
2004-08-29Update copyright to 2004.Bruce Momjian
2003-11-29make sure the $Id tags are converted to $PostgreSQL as well ...PostgreSQL Daemon
2003-08-04Update copyrights to 2003.Bruce Momjian
2002-06-20Update copyright to 2002.Bruce Momjian
2002-05-05Create an internal semaphore API that is not tied to SysV semaphores.Tom Lane
As proof of concept, provide an alternate implementation based on POSIX semaphores. Also push the SysV shared-memory implementation into a separate file so that it can be replaced conveniently.
2001-11-05New pgindent run with fixes suggested by Tom. Patch manually reviewed,Bruce Momjian
initdb/regression tests pass.
2001-10-28Another pgindent run. Fixes enum indenting, and improves #endifBruce Momjian
spacing. Also adds space for one-line comments.
2001-10-25pgindent run on all C files. Java run to follow. initdb/regressionBruce Momjian
tests pass.
2001-09-29Implement new 'lightweight lock manager' that's intermediate betweenTom Lane
existing lock manager and spinlocks: it understands exclusive vs shared lock but has few other fancy features. Replace most uses of spinlocks with lightweight locks. All remaining uses of spinlocks have very short lock hold times (a few dozen instructions), so tweak spinlock backoff code to work efficiently given this assumption. All per my proposal on pghackers 26-Sep-01.
2001-03-22pgindent run. Make it all clean.Bruce Momjian
2001-01-24Change Copyright from PostgreSQL, Inc to PostgreSQL Global Development Group.Bruce Momjian
2000-11-28Significant cleanups in SysV IPC handling (shared mem and semaphores).Tom Lane
IPC key assignment will now work correctly even when multiple postmasters are using same logical port number (which is possible given -k switch). There is only one shared-mem segment per postmaster now, not 3. Rip out broken code for non-TAS case in bufmgr and xlog, substitute a complete S_LOCK emulation using semaphores in spin.c. TAS and non-TAS logic is now exactly the same. When deadlock is detected, "Deadlock detected" is now the elog(ERROR) message, rather than a NOTICE that comes out before an unhelpful ERROR.
2000-05-31The heralded `Grand Unified Configuration scheme' (GUC)Peter Eisentraut
That means you can now set your options in either or all of $PGDATA/configuration, some postmaster option (--enable-fsync=off), or set a SET command. The list of options is in backend/utils/misc/guc.c, documentation will be written post haste. pg_options is gone, so is that pq_geqo config file. Also removed were backend -K, -Q, and -T options (no longer applicable, although -d0 does the same as -Q). Added to configure an --enable-syslog option. changed all callers from TPRINTF to elog(DEBUG)
2000-01-26Add:Bruce Momjian
* Portions Copyright (c) 1996-2000, PostgreSQL, Inc to all files copyright Regents of Berkeley. Man, that's a lot of files.
1999-10-06XLOG (also known as WAL -:)) Bootstrap/Startup/Shutdown.Vadim B. Mikheev
First step in cleaning up backend initialization code. Fix for FATAL: now FATAL is ERROR + exit.
1999-07-15Change #include's to use <> and "" as appropriate.Bruce Momjian
1999-02-13Change my-function-name-- to my_function_name, and optimizer renames.Bruce Momjian