From c3a05aae2d8acca3f216abea61a97e6a9326e699 Mon Sep 17 00:00:00 2001 From: Alvaro Herrera Date: Mon, 4 Mar 2024 11:48:43 +0100 Subject: [PATCH v2 3/3] Simplify coding in slru.c --- src/backend/access/transam/slru.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/src/backend/access/transam/slru.c b/src/backend/access/transam/slru.c index f774d285b7..6895266bf9 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++) -- 2.39.2