VIRTUAL_BUG_ON is an empty macro used in phys_to_nid. This results in two lines of error-checking code in phys_to_nid that is not actually working and causing two compilation errors: 1. error: "MAX_NUMNODES" undeclared (first use in this function). This is because in the common header file, "MAX_NUMNODES" is defined after the common header file includes the ARCH header file, where phys_to_nid has attempted to use "MAX_NUMNODES". This error was resolved after we moved the phys_to_nid from x86 ARCH header file to common header file. 2. error: wrong type argument to unary exclamation mark. This is because, the error-checking code contains !node_data[nid]. But node_data is a data structure variable, it's not a pointer.
So, in this patch, we use ASSERT instead of VIRTUAL_BUG_ON to enable the two lines of error-checking code. And fix the left compilation errors by replacing !node_data[nid] to !node_data[nid].node_spanned_pages. Although NUMA allows one node can only have CPUs but without any memory. And node with 0 bytes of memory might have an entry in memnodemap[] theoretically. But that doesn't mean phys_to_nid can find any valid address from a node with 0 bytes memory. Signed-off-by: Wei Chen <[email protected]> Tested-by: Jiamei Xie <[email protected]> --- v1 -> v2: 1. Move from part#1 to part#2. (Comment from NUMA part1 series) 2. Refine the justification of using !node_data[nid].node_spanned_pages. (From NUMA part1 series) 3. Use ASSERT to replace VIRTUAL_BUG_ON in phys_to_nid. 4. Adjust the conditional express for ASSERT. 5. Move MAX_NUMNODES from xen/numa.h to asm/numa.h for x86. 6. Use conditional macro to gate MAX_NUMNODES for other architectures. --- xen/include/xen/numa.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/xen/include/xen/numa.h b/xen/include/xen/numa.h index db0e524a0e..695ad51df0 100644 --- a/xen/include/xen/numa.h +++ b/xen/include/xen/numa.h @@ -36,8 +36,6 @@ struct node { extern int compute_hash_shift(struct node *nodes, int numnodes, nodeid_t *nodeids); -#define VIRTUAL_BUG_ON(x) - /* Enumerations for NUMA status. */ enum numa_mode { numa_on = 0, @@ -77,9 +75,9 @@ extern struct node_data node_data[]; static inline __attribute__((pure)) nodeid_t phys_to_nid(paddr_t addr) { nodeid_t nid; - VIRTUAL_BUG_ON((paddr_to_pdx(addr) >> memnode_shift) >= memnodemapsize); + ASSERT((paddr_to_pdx(addr) >> memnode_shift) < memnodemapsize); nid = memnodemap[paddr_to_pdx(addr) >> memnode_shift]; - VIRTUAL_BUG_ON(nid >= MAX_NUMNODES || !node_data[nid]); + ASSERT(nid < MAX_NUMNODES && node_data[nid].node_spanned_pages); return nid; } -- 2.25.1
