From: Cliff Wickman <cpw@xxxxxxx>
The numa_num_task_cpus() function should return the number of cpu's
available to the caller. It was returning his highest available cpu
number (+1).
That was an erroneous assumption when the caller is in a cpuset where
available cpu's are not numbered 0..N.
Likewise, numa_num_task_nodes() was doing the same thing.
This patch adds a numa_bitmask_weight() function to count set bits in the map
and makes it available for user convenience as well.
Signed-off-by: Cliff Wickman <cpw@xxxxxxx>
---
libnuma.c | 55 ++++++++++++++++++++++++++++--------------------------
numa.3 | 8 +++++++
versions.ldscript | 1
3 files changed, 38 insertions(+), 26 deletions(-)
Index: numactl-dev/libnuma.c
===================================================================
--- numactl-dev.orig/libnuma.c
+++ numactl-dev/libnuma.c
@@ -67,8 +67,8 @@ static __thread unsigned int mbind_flags
static int sizes_set=0;
static int maxconfigurednode = -1;
static int maxconfiguredcpu = -1;
-static int maxprocnode = -1;
-static int maxproccpu = -1;
+static int numprocnode = -1;
+static int numproccpu = -1;
static int nodemask_sz = 0;
static int cpumask_sz = 0;
@@ -230,6 +230,18 @@ numa_bitmask_equal(const struct bitmask
return 0;
return 1;
}
+
+/* Hamming Weight: number of set bits */
+unsigned int numa_bitmask_weight(const struct bitmask *bmp)
+{
+ unsigned int i;
+ unsigned int w = 0;
+ for (i = 0; i < bmp->size; i++)
+ if (_getbit(bmp, i))
+ w++;
+ return w;
+}
+
/* *****end of bitmask_ routines ************ */
/* Next two can be overwritten by the application for different error handling */
@@ -386,8 +398,7 @@ done:
/*
* Read a mask consisting of a sequence of hexadecimal longs separated by
- * commas. Order them correctly and return the number of the last bit
- * set.
+ * commas. Order them correctly and return the number of bits set.
*/
static int
read_mask(char *s, struct bitmask *bmp)
@@ -436,17 +447,10 @@ read_mask(char *s, struct bitmask *bmp)
bmp->maskp[m++] = x;
}
- m--;
-
- /* Poor mans fls() */
- for(i = bitsperlong - 1; i >= 0; i--)
- if (test_bit(i, bmp->maskp + m))
- break;
-
/*
- * Return the last bit set
+ * Return the number of bits set
*/
- return bitsperlong * m + i;
+ return numa_bitmask_weight(bmp);
}
/*
@@ -477,11 +481,10 @@ set_task_constraints(void)
char *mask = strrchr(buffer,'\t') + 1;
if (strncmp(buffer,"Cpus_allowed:",13) == 0)
- maxproccpu = read_mask(mask, numa_all_cpus_ptr);
+ numproccpu = read_mask(mask, numa_all_cpus_ptr);
if (strncmp(buffer,"Mems_allowed:",13) == 0) {
- maxprocnode =
- read_mask(mask, numa_all_nodes_ptr);
+ numprocnode = read_mask(mask, numa_all_nodes_ptr);
}
}
fclose(f);
@@ -490,26 +493,26 @@ set_task_constraints(void)
/*
* Cpus_allowed in the kernel can be defined to all f's
* i.e. it may be a superset of the actual available processors.
- * As such let's reduce maxproccpu to the number of actual
- * available cpus - 1.
+ * As such let's reduce numproccpu to the number of actual
+ * available cpus.
*/
- if (maxproccpu <= 0) {
+ if (numproccpu <= 0) {
for (i = 0; i <= hicpu; i++)
numa_bitmask_setbit(numa_all_cpus_ptr, i);
- maxproccpu = hicpu;
+ numproccpu = hicpu+1;
}
- if (maxproccpu > hicpu) {
- maxproccpu = hicpu;
+ if (numproccpu > hicpu+1) {
+ numproccpu = hicpu+1;
for (i=hicpu+1; i<numa_all_cpus_ptr->size; i++) {
numa_bitmask_clearbit(numa_all_cpus_ptr, i);
}
}
- if (maxprocnode <= 0) {
+ if (numprocnode <= 0) {
for (i = 0; i <= maxconfigurednode; i++)
numa_bitmask_setbit(numa_all_nodes_ptr, i);
- maxprocnode = maxconfigurednode;
+ numprocnode = maxconfigurednode + 1;
}
return;
@@ -632,7 +635,7 @@ numa_num_possible_cpus(void)
int
numa_num_task_nodes(void)
{
- return maxprocnode+1;
+ return numprocnode;
}
/*
@@ -647,7 +650,7 @@ numa_num_thread_nodes(void)
int
numa_num_task_cpus(void)
{
- return maxproccpu+1;
+ return numproccpu;
}
/*
Index: numactl-dev/numa.3
===================================================================
--- numactl-dev.orig/numa.3
+++ numactl-dev/numa.3
@@ -149,6 +149,8 @@ numa \- NUMA policy library
.BI "void copy_nodemask_to_bitmask(nodemask_t *" nodemask ", struct bitmask *" bmp )
.br
.BI "void copy_bitmask_to_bitmask(struct bitmask *" bmpfrom ", struct bitmask *" bmpto )
+.br
+.BI "unsigned int numa_bitmask_weight(const struct bitmask *bmp )
.sp
.BI "int numa_move_pages(int " pid ", unsigned long " count ", void **" pages ", const int *" nodes ", int *" status ", int " flags );
.br
@@ -860,6 +862,12 @@ pointer to the body of the bitmask struc
pointer. If the two areas differ in size, the copy is truncated to the size
of the receiving field or zero-filled.
+.BR numa_bitmask_weight()
+returns a count of the bits that are set in the body of the bitmask pointed
+to by the
+.I bmp
+argument.
+
.br
.BR numa_move_pages()
moves a list of pages in the address space of the currently
Index: numactl-dev/versions.ldscript
===================================================================
--- numactl-dev.orig/versions.ldscript
+++ numactl-dev/versions.ldscript
@@ -100,6 +100,7 @@ libnuma_1.2 {
numa_bitmask_nbytes;
numa_bitmask_setall;
numa_bitmask_setbit;
+ numa_bitmask_weight;
numa_distance;
numa_error;
numa_exit_on_error;
--
To unsubscribe from this list: send the line "unsubscribe linux-numa" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
