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-rw-r--r--lib/Kconfig.debug9
-rw-r--r--lib/cpumask.c52
-rw-r--r--lib/find_bit.c9
3 files changed, 47 insertions, 23 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 02ee440f7be3..3509115a0e85 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -389,6 +389,15 @@ config PAHOLE_HAS_BTF_TAG
btf_decl_tag) or not. Currently only clang compiler implements
these attributes, so make the config depend on CC_IS_CLANG.
+config PAHOLE_HAS_LANG_EXCLUDE
+ def_bool PAHOLE_VERSION >= 124
+ help
+ Support for the --lang_exclude flag which makes pahole exclude
+ compilation units from the supplied language. Used in Kbuild to
+ omit Rust CUs which are not supported in version 1.24 of pahole,
+ otherwise it would emit malformed kernel and module binaries when
+ using DEBUG_INFO_BTF_MODULES.
+
config DEBUG_INFO_BTF_MODULES
def_bool y
depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF
diff --git a/lib/cpumask.c b/lib/cpumask.c
index c7c392514fd3..e7258836b60b 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -110,15 +110,33 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask)
#endif
/**
- * cpumask_local_spread - select the i'th cpu with local numa cpu's first
+ * cpumask_local_spread - select the i'th cpu based on NUMA distances
* @i: index number
* @node: local numa_node
*
- * This function selects an online CPU according to a numa aware policy;
- * local cpus are returned first, followed by non-local ones, then it
- * wraps around.
+ * Returns online CPU according to a numa aware policy; local cpus are returned
+ * first, followed by non-local ones, then it wraps around.
*
- * It's not very efficient, but useful for setup.
+ * For those who wants to enumerate all CPUs based on their NUMA distances,
+ * i.e. call this function in a loop, like:
+ *
+ * for (i = 0; i < num_online_cpus(); i++) {
+ * cpu = cpumask_local_spread(i, node);
+ * do_something(cpu);
+ * }
+ *
+ * There's a better alternative based on for_each()-like iterators:
+ *
+ * for_each_numa_hop_mask(mask, node) {
+ * for_each_cpu_andnot(cpu, mask, prev)
+ * do_something(cpu);
+ * prev = mask;
+ * }
+ *
+ * It's simpler and more verbose than above. Complexity of iterator-based
+ * enumeration is O(sched_domains_numa_levels * nr_cpu_ids), while
+ * cpumask_local_spread() when called for each cpu is
+ * O(sched_domains_numa_levels * nr_cpu_ids * log(nr_cpu_ids)).
*/
unsigned int cpumask_local_spread(unsigned int i, int node)
{
@@ -127,24 +145,12 @@ unsigned int cpumask_local_spread(unsigned int i, int node)
/* Wrap: we always want a cpu. */
i %= num_online_cpus();
- if (node == NUMA_NO_NODE) {
- cpu = cpumask_nth(i, cpu_online_mask);
- if (cpu < nr_cpu_ids)
- return cpu;
- } else {
- /* NUMA first. */
- cpu = cpumask_nth_and(i, cpu_online_mask, cpumask_of_node(node));
- if (cpu < nr_cpu_ids)
- return cpu;
-
- i -= cpumask_weight_and(cpu_online_mask, cpumask_of_node(node));
-
- /* Skip NUMA nodes, done above. */
- cpu = cpumask_nth_andnot(i, cpu_online_mask, cpumask_of_node(node));
- if (cpu < nr_cpu_ids)
- return cpu;
- }
- BUG();
+ cpu = (node == NUMA_NO_NODE) ?
+ cpumask_nth(i, cpu_online_mask) :
+ sched_numa_find_nth_cpu(cpu_online_mask, i, node);
+
+ WARN_ON(cpu >= nr_cpu_ids);
+ return cpu;
}
EXPORT_SYMBOL(cpumask_local_spread);
diff --git a/lib/find_bit.c b/lib/find_bit.c
index 18bc0a7ac8ee..c10920e66788 100644
--- a/lib/find_bit.c
+++ b/lib/find_bit.c
@@ -155,6 +155,15 @@ unsigned long __find_nth_andnot_bit(const unsigned long *addr1, const unsigned l
}
EXPORT_SYMBOL(__find_nth_andnot_bit);
+unsigned long __find_nth_and_andnot_bit(const unsigned long *addr1,
+ const unsigned long *addr2,
+ const unsigned long *addr3,
+ unsigned long size, unsigned long n)
+{
+ return FIND_NTH_BIT(addr1[idx] & addr2[idx] & ~addr3[idx], size, n);
+}
+EXPORT_SYMBOL(__find_nth_and_andnot_bit);
+
#ifndef find_next_and_bit
unsigned long _find_next_and_bit(const unsigned long *addr1, const unsigned long *addr2,
unsigned long nbits, unsigned long start)