diff options
| -rw-r--r-- | src/include/storage/buf_internals.h | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/src/include/storage/buf_internals.h b/src/include/storage/buf_internals.h index 1a65342177d..d830d5c9841 100644 --- a/src/include/storage/buf_internals.h +++ b/src/include/storage/buf_internals.h @@ -39,12 +39,19 @@ * * The definition of buffer state components is below. */ +#define BUF_REFCOUNT_BITS 18 +#define BUF_USAGECOUNT_BITS 4 +#define BUF_FLAG_BITS 10 + +StaticAssertDecl(BUF_REFCOUNT_BITS + BUF_USAGECOUNT_BITS + BUF_FLAG_BITS == 32, + "parts of buffer state space need to equal 32"); + #define BUF_REFCOUNT_ONE 1 -#define BUF_REFCOUNT_MASK ((1U << 18) - 1) -#define BUF_USAGECOUNT_MASK 0x003C0000U -#define BUF_USAGECOUNT_ONE (1U << 18) -#define BUF_USAGECOUNT_SHIFT 18 -#define BUF_FLAG_MASK 0xFFC00000U +#define BUF_REFCOUNT_MASK ((1U << BUF_REFCOUNT_BITS) - 1) +#define BUF_USAGECOUNT_MASK (((1U << BUF_USAGECOUNT_BITS) - 1) << (BUF_REFCOUNT_BITS)) +#define BUF_USAGECOUNT_ONE (1U << BUF_REFCOUNT_BITS) +#define BUF_USAGECOUNT_SHIFT BUF_REFCOUNT_BITS +#define BUF_FLAG_MASK (((1U << BUF_FLAG_BITS) - 1) << (BUF_REFCOUNT_BITS + BUF_USAGECOUNT_BITS)) /* Get refcount and usagecount from buffer state */ #define BUF_STATE_GET_REFCOUNT(state) ((state) & BUF_REFCOUNT_MASK) @@ -77,6 +84,9 @@ */ #define BM_MAX_USAGE_COUNT 5 +StaticAssertDecl(BM_MAX_USAGE_COUNT < (1 << BUF_USAGECOUNT_BITS), + "BM_MAX_USAGE_COUNT doesn't fit in BUF_USAGECOUNT_BITS bits"); + /* * Buffer tag identifies which disk block the buffer contains. * |