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| author | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2024-03-04 17:37:47 +0100 |
|---|---|---|
| committer | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2024-03-04 17:37:47 +0100 |
| commit | f9baaf96d3395c3afc2c558fb74279c4923ddb24 (patch) | |
| tree | 00c4036a1f6c9a5d7fbf3efbbb4a74d15b4a99ba /src | |
| parent | c8a61e350db40f81e088f2333fd30cc7f96a8b35 (diff) | |
| download | postgresql-f9baaf96d3395c3afc2c558fb74279c4923ddb24.tar.gz postgresql-f9baaf96d3395c3afc2c558fb74279c4923ddb24.zip | |
Simplify coding in slru.c
New code in 53c2a97a9266 uses direct array access to
shared->bank_locks[bankno].lock which can be made a little bit more
legible by using the SimpleLruGetBankLock helper function.
Nothing terribly serious, but let's add some clarity.
Discussion: https://postgr.es/m/202403041517.3a35jw53os65@alvherre.pgsql
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/access/transam/slru.c | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c index f774d285b7f..6895266bf9d 100644 --- a/src/backend/access/transam/slru.c +++ b/src/backend/access/transam/slru.c @@ -489,14 +489,14 @@ SimpleLruReadPage(SlruCtl ctl, int64 pageno, bool write_ok, TransactionId xid) { SlruShared shared = ctl->shared; + LWLock *banklock = SimpleLruGetBankLock(ctl, pageno); - Assert(LWLockHeldByMeInMode(SimpleLruGetBankLock(ctl, pageno), LW_EXCLUSIVE)); + Assert(LWLockHeldByMeInMode(banklock, LW_EXCLUSIVE)); /* Outer loop handles restart if we must wait for someone else's I/O */ for (;;) { int slotno; - int bankno; bool ok; /* See if page already is in memory; if not, pick victim slot */ @@ -539,10 +539,9 @@ SimpleLruReadPage(SlruCtl ctl, int64 pageno, bool write_ok, /* Acquire per-buffer lock (cannot deadlock, see notes at top) */ LWLockAcquire(&shared->buffer_locks[slotno].lock, LW_EXCLUSIVE); - bankno = SlotGetBankNumber(slotno); /* Release bank lock while doing I/O */ - LWLockRelease(&shared->bank_locks[bankno].lock); + LWLockRelease(banklock); /* Do the read */ ok = SlruPhysicalReadPage(ctl, pageno, slotno); @@ -551,7 +550,7 @@ SimpleLruReadPage(SlruCtl ctl, int64 pageno, bool write_ok, SimpleLruZeroLSNs(ctl, slotno); /* Re-acquire bank control lock and update page state */ - LWLockAcquire(&shared->bank_locks[bankno].lock, LW_EXCLUSIVE); + LWLockAcquire(banklock, LW_EXCLUSIVE); Assert(shared->page_number[slotno] == pageno && shared->page_status[slotno] == SLRU_PAGE_READ_IN_PROGRESS && @@ -592,12 +591,13 @@ int SimpleLruReadPage_ReadOnly(SlruCtl ctl, int64 pageno, TransactionId xid) { SlruShared shared = ctl->shared; + LWLock *banklock = SimpleLruGetBankLock(ctl, pageno); int bankno = pageno & ctl->bank_mask; int bankstart = bankno * SLRU_BANK_SIZE; int bankend = bankstart + SLRU_BANK_SIZE; /* Try to find the page while holding only shared lock */ - LWLockAcquire(&shared->bank_locks[bankno].lock, LW_SHARED); + LWLockAcquire(banklock, LW_SHARED); /* See if page is already in a buffer */ for (int slotno = bankstart; slotno < bankend; slotno++) @@ -617,8 +617,8 @@ SimpleLruReadPage_ReadOnly(SlruCtl ctl, int64 pageno, TransactionId xid) } /* No luck, so switch to normal exclusive lock and do regular read */ - LWLockRelease(&shared->bank_locks[bankno].lock); - LWLockAcquire(&shared->bank_locks[bankno].lock, LW_EXCLUSIVE); + LWLockRelease(banklock); + LWLockAcquire(banklock, LW_EXCLUSIVE); return SimpleLruReadPage(ctl, pageno, true, xid); } @@ -1167,7 +1167,7 @@ SlruSelectLRUPage(SlruCtl ctl, int64 pageno) int bankstart = bankno * SLRU_BANK_SIZE; int bankend = bankstart + SLRU_BANK_SIZE; - Assert(LWLockHeldByMe(&shared->bank_locks[bankno].lock)); + Assert(LWLockHeldByMe(SimpleLruGetBankLock(ctl, pageno))); /* See if page already has a buffer assigned */ for (int slotno = 0; slotno < shared->num_slots; slotno++) |