ia64: export node_distance function (ef78e5ec) · Commits · 戴 / test

The numa_slit variable used by node_distance is available to a module as long as it is linked at compile-time. However, it is not available to loadable modules. Leading to errors such as: ERROR: "numa_slit" [drivers/nvme/host/nvme-core.ko] undefined! The error above is caused by the nvme multipath code that makes use of node_distance for its path calculation. When the patch was added, the lightnvm subsystem would select nvme and always compile it in, leading to the node_distance call to always succeed. However, when this requirement was removed, nvme could be compiled in as a module, which exposed this bug. This patch extracts node_distance to a function and exports it. Since ACPI is depending on node_distance being a simple lookup to numa_slit, the previous behavior is exposed as slit_distance and its users updated. Fixes: "nvme: take node locality into account when selecting a path" Fixes: "lightnvm: remove dependencies on BLK_DEV_NVME and PCI" Signed-off-by:

Matias Bjøring <mb@lightnvm.io> Signed-off-by:

Tony Luck <tony.luck@intel.com> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

arch/ia64/include/asm/numa.h

+3 −1

Original line number	Diff line number	Diff line
		@@ -59,7 +59,9 @@ extern struct node_cpuid_s node_cpuid[NR_CPUS];
		*/

		extern u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
		#define node_distance(from,to) (numa_slit[(from) * MAX_NUMNODES + (to)])
		#define slit_distance(from,to) (numa_slit[(from) * MAX_NUMNODES + (to)])
		extern int __node_distance(int from, int to);
		#define node_distance(from,to) __node_distance(from, to)

		extern int paddr_to_nid(unsigned long paddr);

arch/ia64/kernel/acpi.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -578,8 +578,8 @@ void __init acpi_numa_fixup(void)
		if (!slit_table) {
		for (i = 0; i < MAX_NUMNODES; i++)
		for (j = 0; j < MAX_NUMNODES; j++)
		node_distance(i, j) = i == j ? LOCAL_DISTANCE :
		REMOTE_DISTANCE;
		slit_distance(i, j) = i == j ?
		LOCAL_DISTANCE : REMOTE_DISTANCE;
		return;
		}

		@@ -592,7 +592,7 @@ void __init acpi_numa_fixup(void)
		if (!pxm_bit_test(j))
		continue;
		node_to = pxm_to_node(j);
		node_distance(node_from, node_to) =
		slit_distance(node_from, node_to) =
		slit_table->entry[i * slit_table->locality_count + j];
		}
		}

arch/ia64/mm/numa.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -36,6 +36,12 @@ struct node_cpuid_s node_cpuid[NR_CPUS] =
		*/
		u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];

		int __node_distance(int from, int to)
		{
		return slit_distance(from, to);
		}
		EXPORT_SYMBOL(__node_distance);

		/* Identify which cnode a physical address resides on */
		int
		paddr_to_nid(unsigned long paddr)

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