Ryan Harper
2005-Dec-16 23:13 UTC
[Xen-devel] [PATCH] 6/7 xen: Add basic NUMA support - Physinfo nr_cpus
This patch adds a new field to physinfo, nr_cpus, which previously has
been calculated by the following formula:
nr_cpus = nr_nodes * sockets_per_node * cores_per_socket * \
threads_per_core
This formula makes an assumption about the symmetry of NUMA nodes. For
instance, on my Dual Opteron, which is a two node system with one cpu in
each node, sockets_per_node is calculated as 2, but this is incorrect.
There isn''t a single value for sockets per node, but rather, it should
be a list of values, which is generated by taking the Hamming weight of
each node''s cpumask.
In Xen, there aren''t a large number of uses for sockets_per_node other
than calculating the number of cpus booted in the hypervisor. Instead
of dealing with making another array in physinfo, I''ve opted to add
nr_cpus which is based on num_online_cpus() and replaced all instances
of the nr_cpus formula with a reference to the proper nr_cpus value that
is now contained in the physinfo.
--
Ryan Harper
Software Engineer; Linux Technology Center
IBM Corp., Austin, Tx
(512) 838-9253 T/L: 678-9253
ryanh@us.ibm.com
diffstat output:
tools/python/xen/lowlevel/xc/xc.c | 3 ++-
tools/python/xen/xend/XendNode.py | 4 ----
tools/xenmon/xenbaked.c | 5 +----
tools/xentrace/xentrace.c | 5 +----
xen/arch/ia64/xen/dom0_ops.c | 1 +
xen/arch/x86/dom0_ops.c | 1 +
xen/include/public/dom0_ops.h | 1 +
7 files changed, 7 insertions(+), 13 deletions(-)
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Signed-off-by: Ryan Grimm <grimm@us.ibm.com>
---
diff -r 398a0cdf3e31 -r f9779dd3e52b tools/python/xen/lowlevel/xc/xc.c
--- a/tools/python/xen/lowlevel/xc/xc.c Fri Dec 16 17:02:16 2005
+++ b/tools/python/xen/lowlevel/xc/xc.c Fri Dec 16 17:47:48 2005
@@ -623,10 +623,11 @@
if(q>cpu_cap)
*(q-1)=0;
- ret_obj = Py_BuildValue("{s:i,s:i,s:i,s:l,s:l,s:i,s:s}",
+ ret_obj = Py_BuildValue("{s:i,s:i,s:i,s:i,s:l,s:l,s:i,s:s}",
"threads_per_core", info.threads_per_core,
"cores_per_socket", info.cores_per_socket,
"sockets_per_node", info.sockets_per_node,
+ "nr_cpus" , info.nr_cpus,
"total_memory",
pages_to_mb(info.total_pages),
"free_memory",
pages_to_mb(info.free_pages),
"cpu_khz", info.cpu_khz,
diff -r 398a0cdf3e31 -r f9779dd3e52b tools/python/xen/xend/XendNode.py
--- a/tools/python/xen/xend/XendNode.py Fri Dec 16 17:02:16 2005
+++ b/tools/python/xen/xend/XendNode.py Fri Dec 16 17:47:48 2005
@@ -122,10 +122,6 @@
def physinfo(self):
info = self.xc.physinfo()
- info[''nr_cpus''] = (info[''nr_nodes'']
*
- info[''sockets_per_node''] *
- info[''cores_per_socket''] *
- info[''threads_per_core''])
info[''cpu_mhz''] = info[''cpu_khz''] /
1000
info[''mem_chunks''] = self.format_memchunks(info)
info[''node_to_cpu''] = self.format_node_to_cpu(info)
diff -r 398a0cdf3e31 -r f9779dd3e52b tools/xenmon/xenbaked.c
--- a/tools/xenmon/xenbaked.c Fri Dec 16 17:02:16 2005
+++ b/tools/xenmon/xenbaked.c Fri Dec 16 17:47:48 2005
@@ -399,10 +399,7 @@
xc_interface_close(xc_handle);
opts.cpu_freq = (double)op.u.physinfo.cpu_khz/1000.0;
- return (op.u.physinfo.threads_per_core *
- op.u.physinfo.cores_per_socket *
- op.u.physinfo.sockets_per_node *
- op.u.physinfo.nr_nodes);
+ return op.u.physinfo.nr_cpus;
}
diff -r 398a0cdf3e31 -r f9779dd3e52b tools/xentrace/xentrace.c
--- a/tools/xentrace/xentrace.c Fri Dec 16 17:02:16 2005
+++ b/tools/xentrace/xentrace.c Fri Dec 16 17:47:48 2005
@@ -277,10 +277,7 @@
xc_interface_close(xc_handle);
- return (op.u.physinfo.threads_per_core *
- op.u.physinfo.cores_per_socket *
- op.u.physinfo.sockets_per_node *
- op.u.physinfo.nr_nodes);
+ return op.u.physinfo.nr_cpus;
}
diff -r 398a0cdf3e31 -r f9779dd3e52b xen/arch/ia64/xen/dom0_ops.c
--- a/xen/arch/ia64/xen/dom0_ops.c Fri Dec 16 17:02:16 2005
+++ b/xen/arch/ia64/xen/dom0_ops.c Fri Dec 16 17:47:48 2005
@@ -204,6 +204,7 @@
pi->sockets_per_node =
num_online_cpus() / (pi->threads_per_core *
pi->cores_per_socket);
pi->nr_nodes = 1;
+ pi->nr_cpus = (u32)num_online_cpus();
pi->total_pages = 99; // FIXME
pi->free_pages = avail_domheap_pages();
pi->cpu_khz = 100; // FIXME cpu_khz;
diff -r 398a0cdf3e31 -r f9779dd3e52b xen/arch/x86/dom0_ops.c
--- a/xen/arch/x86/dom0_ops.c Fri Dec 16 17:02:16 2005
+++ b/xen/arch/x86/dom0_ops.c Fri Dec 16 17:47:48 2005
@@ -188,6 +188,7 @@
pi->cores_per_socket = boot_cpu_data.x86_num_cores;
pi->sockets_per_node =
num_online_cpus() / (pi->threads_per_core *
pi->cores_per_socket);
+ pi->nr_cpus = (u32)num_online_cpus();
pi->total_pages = total_pages;
pi->free_pages = avail_domheap_pages();
pi->cpu_khz = cpu_khz;
diff -r 398a0cdf3e31 -r f9779dd3e52b xen/include/public/dom0_ops.h
--- a/xen/include/public/dom0_ops.h Fri Dec 16 17:02:16 2005
+++ b/xen/include/public/dom0_ops.h Fri Dec 16 17:47:48 2005
@@ -200,6 +200,7 @@
uint32_t cores_per_socket;
uint32_t sockets_per_node;
uint32_t nr_nodes;
+ uint32_t nr_cpus;
uint32_t cpu_khz;
unsigned long total_pages;
unsigned long free_pages;
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