Merge branch 'x86-numa-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-numa-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, numa: Remove configurable node size support for numa emulation
  x86, numa: Add fixed node size option for numa emulation
  x86, numa: Fix numa emulation calculation of big nodes
  x86, acpi: Map hotadded cpu to correct node.

1 files changed, 101 insertions, 134 deletions

diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c
index 83bbc70d11b..3307ea8bd43 100644
--- a/arch/x86/mm/numa_64.c
+++ b/arch/x86/mm/numa_64.c
@@ -427,7 +427,7 @@ static int __init split_nodes_interleave(u64 addr, u64 max_addr,
          * Calculate the number of big nodes that can be allocated as a result
          * of consolidating the remainder.
          */
-        big = ((size & ~FAKE_NODE_MIN_HASH_MASK) & nr_nodes) /
+        big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * nr_nodes) /
                 FAKE_NODE_MIN_SIZE;
 
         size &= FAKE_NODE_MIN_HASH_MASK;
@@ -502,77 +502,99 @@ static int __init split_nodes_interleave(u64 addr, u64 max_addr,
 }
 
 /*
- * Splits num_nodes nodes up equally starting at node_start.  The return value
- * is the number of nodes split up and addr is adjusted to be at the end of the
- * last node allocated.
+ * Returns the end address of a node so that there is at least `size' amount of
+ * non-reserved memory or `max_addr' is reached.
  */
-static int __init split_nodes_equally(u64 *addr, u64 max_addr, int node_start,
-                                      int num_nodes)
+static u64 __init find_end_of_node(u64 start, u64 max_addr, u64 size)
 {
-        unsigned int big;
-        u64 size;
-        int i;
-
-        if (num_nodes <= 0)
-                return -1;
-        if (num_nodes > MAX_NUMNODES)
-                num_nodes = MAX_NUMNODES;
-        size = (max_addr - *addr - e820_hole_size(*addr, max_addr)) /
-               num_nodes;
-        /*
-         * Calculate the number of big nodes that can be allocated as a result
-         * of consolidating the leftovers.
-         */
-        big = ((size & ~FAKE_NODE_MIN_HASH_MASK) * num_nodes) /
-              FAKE_NODE_MIN_SIZE;
-
-        /* Round down to nearest FAKE_NODE_MIN_SIZE. */
-        size &= FAKE_NODE_MIN_HASH_MASK;
-        if (!size) {
-                printk(KERN_ERR "Not enough memory for each node.  "
-                       "NUMA emulation disabled.\n");
-                return -1;
-        }
-
-        for (i = node_start; i < num_nodes + node_start; i++) {
-                u64 end = *addr + size;
+        u64 end = start + size;
 
-                if (i < big)
-                        end += FAKE_NODE_MIN_SIZE;
-                /*
-                 * The final node can have the remaining system RAM.  Other
-                 * nodes receive roughly the same amount of available pages.
-                 */
-                if (i == num_nodes + node_start - 1)
+        while (end - start - e820_hole_size(start, end) < size) {
+                end += FAKE_NODE_MIN_SIZE;
+                if (end > max_addr) {
                         end = max_addr;
-                else
-                        while (end - *addr - e820_hole_size(*addr, end) <
-                               size) {
-                                end += FAKE_NODE_MIN_SIZE;
-                                if (end > max_addr) {
-                                        end = max_addr;
-                                        break;
-                                }
-                        }
-                if (setup_node_range(i, addr, end - *addr, max_addr) < 0)
                         break;
+                }
         }
-        return i - node_start + 1;
+        return end;
 }
 
 /*
- * Splits the remaining system RAM into chunks of size.  The remaining memory is
- * always assigned to a final node and can be asymmetric.  Returns the number of
- * nodes split.
+ * Sets up fake nodes of `size' interleaved over physical nodes ranging from
+ * `addr' to `max_addr'.  The return value is the number of nodes allocated.
  */
-static int __init split_nodes_by_size(u64 *addr, u64 max_addr, int node_start,
-                                      u64 size)
+static int __init split_nodes_size_interleave(u64 addr, u64 max_addr, u64 size)
 {
-        int i = node_start;
-        size = (size << 20) & FAKE_NODE_MIN_HASH_MASK;
-        while (!setup_node_range(i++, addr, size, max_addr))
-                ;
-        return i - node_start;
+        nodemask_t physnode_mask = NODE_MASK_NONE;
+        u64 min_size;
+        int ret = 0;
+        int i;
+
+        if (!size)
+                return -1;
+        /*
+         * The limit on emulated nodes is MAX_NUMNODES, so the size per node is
+         * increased accordingly if the requested size is too small.  This
+         * creates a uniform distribution of node sizes across the entire
+         * machine (but not necessarily over physical nodes).
+         */
+        min_size = (max_addr - addr - e820_hole_size(addr, max_addr)) /
+                                                MAX_NUMNODES;
+        min_size = max(min_size, FAKE_NODE_MIN_SIZE);
+        if ((min_size & FAKE_NODE_MIN_HASH_MASK) < min_size)
+                min_size = (min_size + FAKE_NODE_MIN_SIZE) &
+                                                FAKE_NODE_MIN_HASH_MASK;
+        if (size < min_size) {
+                pr_err("Fake node size %LuMB too small, increasing to %LuMB\n",
+                        size >> 20, min_size >> 20);
+                size = min_size;
+        }
+        size &= FAKE_NODE_MIN_HASH_MASK;
+
+        for (i = 0; i < MAX_NUMNODES; i++)
+                if (physnodes[i].start != physnodes[i].end)
+                        node_set(i, physnode_mask);
+        /*
+         * Fill physical nodes with fake nodes of size until there is no memory
+         * left on any of them.
+         */
+        while (nodes_weight(physnode_mask)) {
+                for_each_node_mask(i, physnode_mask) {
+                        u64 dma32_end = MAX_DMA32_PFN << PAGE_SHIFT;
+                        u64 end;
+
+                        end = find_end_of_node(physnodes[i].start,
+                                                physnodes[i].end, size);
+                        /*
+                         * If there won't be at least FAKE_NODE_MIN_SIZE of
+                         * non-reserved memory in ZONE_DMA32 for the next node,
+                         * this one must extend to the boundary.
+                         */
+                        if (end < dma32_end && dma32_end - end -
+                            e820_hole_size(end, dma32_end) < FAKE_NODE_MIN_SIZE)
+                                end = dma32_end;
+
+                        /*
+                         * If there won't be enough non-reserved memory for the
+                         * next node, this one must extend to the end of the
+                         * physical node.
+                         */
+                        if (physnodes[i].end - end -
+                            e820_hole_size(end, physnodes[i].end) < size)
+                                end = physnodes[i].end;
+
+                        /*
+                         * Setup the fake node that will be allocated as bootmem
+                         * later.  If setup_node_range() returns non-zero, there
+                         * is no more memory available on this physical node.
+                         */
+                        if (setup_node_range(ret++, &physnodes[i].start,
+                                                end - physnodes[i].start,
+                                                physnodes[i].end) < 0)
+                                node_clear(i, physnode_mask);
+                }
+        }
+        return ret;
 }
 
 /*
@@ -582,87 +604,32 @@ static int __init split_nodes_by_size(u64 *addr, u64 max_addr, int node_start,
 static int __init numa_emulation(unsigned long start_pfn,
                         unsigned long last_pfn, int acpi, int k8)
 {
-        u64 size, addr = start_pfn << PAGE_SHIFT;
+        u64 addr = start_pfn << PAGE_SHIFT;
         u64 max_addr = last_pfn << PAGE_SHIFT;
-        int num_nodes = 0, num = 0, coeff_flag, coeff = -1, i;
         int num_phys_nodes;
+        int num_nodes;
+        int i;
 
         num_phys_nodes = setup_physnodes(addr, max_addr, acpi, k8);
         /*
-         * If the numa=fake command-line is just a single number N, split the
-         * system RAM into N fake nodes.
+         * If the numa=fake command-line contains a 'M' or 'G', it represents
+         * the fixed node size.  Otherwise, if it is just a single number N,
+         * split the system RAM into N fake nodes.
          */
-        if (!strchr(cmdline, '*') && !strchr(cmdline, ',')) {
-                long n = simple_strtol(cmdline, NULL, 0);
-
-                num_nodes = split_nodes_interleave(addr, max_addr,
-                                                        num_phys_nodes, n);
-                if (num_nodes < 0)
-                        return num_nodes;
-                goto out;
-        }
+        if (strchr(cmdline, 'M') || strchr(cmdline, 'G')) {
+                u64 size;
 
-        /* Parse the command line. */
-        for (coeff_flag = 0; ; cmdline++) {
-                if (*cmdline && isdigit(*cmdline)) {
-                        num = num * 10 + *cmdline - '0';
-                        continue;
-                }
-                if (*cmdline == '*') {
-                        if (num > 0)
-                                coeff = num;
-                        coeff_flag = 1;
-                }
-                if (!*cmdline || *cmdline == ',') {
-                        if (!coeff_flag)
-                                coeff = 1;
-                        /*
-                         * Round down to the nearest FAKE_NODE_MIN_SIZE.
-                         * Command-line coefficients are in megabytes.
-                         */
-                        size = ((u64)num << 20) & FAKE_NODE_MIN_HASH_MASK;
-                        if (size)
-                                for (i = 0; i < coeff; i++, num_nodes++)
-                                        if (setup_node_range(num_nodes, &addr,
-                                                size, max_addr) < 0)
-                                                goto done;
-                        if (!*cmdline)
-                                break;
-                        coeff_flag = 0;
-                        coeff = -1;
-                }
-                num = 0;
-        }
-done:
-        if (!num_nodes)
-                return -1;
-        /* Fill remainder of system RAM, if appropriate. */
-        if (addr < max_addr) {
-                if (coeff_flag && coeff < 0) {
-                        /* Split remaining nodes into num-sized chunks */
-                        num_nodes += split_nodes_by_size(&addr, max_addr,
-                                                         num_nodes, num);
-                        goto out;
-                }
-                switch (*(cmdline - 1)) {
-                case '*':
-                        /* Split remaining nodes into coeff chunks */
-                        if (coeff <= 0)
-                                break;
-                        num_nodes += split_nodes_equally(&addr, max_addr,
-                                                         num_nodes, coeff);
-                        break;
-                case ',':
-                        /* Do not allocate remaining system RAM */
-                        break;
-                default:
-                        /* Give one final node */
-                        setup_node_range(num_nodes, &addr, max_addr - addr,
-                                         max_addr);
-                        num_nodes++;
-                }
+                size = memparse(cmdline, &cmdline);
+                num_nodes = split_nodes_size_interleave(addr, max_addr, size);
+        } else {
+                unsigned long n;
+
+                n = simple_strtoul(cmdline, NULL, 0);
+                num_nodes = split_nodes_interleave(addr, max_addr, num_phys_nodes, n);
         }
-out:
+
+        if (num_nodes < 0)
+                return num_nodes;
         memnode_shift = compute_hash_shift(nodes, num_nodes, NULL);
         if (memnode_shift < 0) {
                 memnode_shift = 0;