diff options
Diffstat (limited to 'src/backend/storage/buffer/localbuf.c')
| -rw-r--r-- | src/backend/storage/buffer/localbuf.c | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/src/backend/storage/buffer/localbuf.c b/src/backend/storage/buffer/localbuf.c index 8efde05c0a5..f172a5c7820 100644 --- a/src/backend/storage/buffer/localbuf.c +++ b/src/backend/storage/buffer/localbuf.c @@ -183,6 +183,13 @@ FlushLocalBuffer(BufferDesc *bufHdr, SMgrRelation reln) instr_time io_start; Page localpage = (char *) LocalBufHdrGetBlock(bufHdr); + /* + * Try to start an I/O operation. There currently are no reasons for + * StartLocalBufferIO to return false, so we raise an error in that case. + */ + if (!StartLocalBufferIO(bufHdr, false)) + elog(ERROR, "failed to start write IO on local buffer"); + /* Find smgr relation for buffer */ if (reln == NULL) reln = smgropen(BufTagGetRelFileLocator(&bufHdr->tag), @@ -406,11 +413,17 @@ ExtendBufferedRelLocal(BufferManagerRelation bmr, PinLocalBuffer(existing_hdr, false); buffers[i] = BufferDescriptorGetBuffer(existing_hdr); + /* + * Clear the BM_VALID bit, do StartLocalBufferIO() and proceed. + */ buf_state = pg_atomic_read_u32(&existing_hdr->state); Assert(buf_state & BM_TAG_VALID); Assert(!(buf_state & BM_DIRTY)); buf_state &= ~BM_VALID; pg_atomic_unlocked_write_u32(&existing_hdr->state, buf_state); + + /* no need to loop for local buffers */ + StartLocalBufferIO(existing_hdr, true); } else { @@ -425,6 +438,8 @@ ExtendBufferedRelLocal(BufferManagerRelation bmr, pg_atomic_unlocked_write_u32(&victim_buf_hdr->state, buf_state); hresult->id = victim_buf_id; + + StartLocalBufferIO(victim_buf_hdr, true); } } @@ -490,6 +505,27 @@ MarkLocalBufferDirty(Buffer buffer) } /* + * Like StartBufferIO, but for local buffers + */ +bool +StartLocalBufferIO(BufferDesc *bufHdr, bool forInput) +{ + uint32 buf_state = pg_atomic_read_u32(&bufHdr->state); + + if (forInput ? (buf_state & BM_VALID) : !(buf_state & BM_DIRTY)) + { + /* someone else already did the I/O */ + return false; + } + + /* BM_IO_IN_PROGRESS isn't currently used for local buffers */ + + /* local buffers don't track IO using resowners */ + + return true; +} + +/* * Like TerminateBufferIO, but for local buffers */ void |