The quilt patch titled
Subject: mm: hugetlb: add hugetlb_alloc_threads cmdline option
has been removed from the -mm tree. Its filename was
mm-hugetlb-add-hugetlb_alloc_threads-cmdline-option.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Thomas Prescher <thomas.prescher@xxxxxxxxxxxxxxxxxxxxx>
Subject: mm: hugetlb: add hugetlb_alloc_threads cmdline option
Date: Thu, 27 Feb 2025 23:45:06 +0100
Add a command line option that enables control of how many threads should
be used to allocate huge pages.
[akpm@xxxxxxxxxxxxxxxxxxxx: tidy up a comment]
Link: https://lkml.kernel.org/r/20250227-hugepage-parameter-v2-2-7db8c6dc0453@xxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Thomas Prescher <thomas.prescher@xxxxxxxxxxxxxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/admin-guide/kernel-parameters.txt | 9 +++
Documentation/admin-guide/mm/hugetlbpage.rst | 10 ++++
mm/hugetlb.c | 33 ++++++++++++--
3 files changed, 48 insertions(+), 4 deletions(-)
--- a/Documentation/admin-guide/kernel-parameters.txt~mm-hugetlb-add-hugetlb_alloc_threads-cmdline-option
+++ a/Documentation/admin-guide/kernel-parameters.txt
@@ -1882,6 +1882,15 @@
Documentation/admin-guide/mm/hugetlbpage.rst.
Format: size[KMG]
+ hugepage_alloc_threads=
+ [HW] The number of threads that should be used to
+ allocate hugepages during boot. This option can be
+ used to improve system bootup time when allocating
+ a large amount of huge pages.
+ The default value is 25% of the available hardware threads.
+
+ Note that this parameter only applies to non-gigantic huge pages.
+
hugetlb_cma= [HW,CMA,EARLY] The size of a CMA area used for allocation
of gigantic hugepages. Or using node format, the size
of a CMA area per node can be specified.
--- a/Documentation/admin-guide/mm/hugetlbpage.rst~mm-hugetlb-add-hugetlb_alloc_threads-cmdline-option
+++ a/Documentation/admin-guide/mm/hugetlbpage.rst
@@ -145,7 +145,17 @@ hugepages
It will allocate 1 2M hugepage on node0 and 2 2M hugepages on node1.
If the node number is invalid, the parameter will be ignored.
+hugepage_alloc_threads
+ Specify the number of threads that should be used to allocate hugepages
+ during boot. This parameter can be used to improve system bootup time
+ when allocating a large amount of huge pages.
+ The default value is 25% of the available hardware threads.
+ Example to use 8 allocation threads::
+
+ hugepage_alloc_threads=8
+
+ Note that this parameter only applies to non-gigantic huge pages.
default_hugepagesz
Specify the default huge page size. This parameter can
only be specified once on the command line. default_hugepagesz can
--- a/mm/hugetlb.c~mm-hugetlb-add-hugetlb_alloc_threads-cmdline-option
+++ a/mm/hugetlb.c
@@ -85,6 +85,7 @@ static unsigned long __initdata default_
static bool __initdata parsed_valid_hugepagesz = true;
static bool __initdata parsed_default_hugepagesz;
static unsigned int default_hugepages_in_node[MAX_NUMNODES] __initdata;
+static unsigned long hugepage_allocation_threads __initdata;
static char hstate_cmdline_buf[COMMAND_LINE_SIZE] __initdata;
static int hstate_cmdline_index __initdata;
@@ -3607,8 +3608,6 @@ static unsigned long __init hugetlb_page
.numa_aware = true
};
- unsigned int num_allocation_threads = max(num_online_cpus() / 4, 1);
-
job.thread_fn = hugetlb_pages_alloc_boot_node;
job.start = 0;
job.size = h->max_huge_pages;
@@ -3629,9 +3628,13 @@ static unsigned long __init hugetlb_page
* | cascade lake 192 cpus | 39s | 20s | 11s | 10s | 9s |
* +-----------------------+-------+-------+-------+-------+-------+
*/
+ if (hugepage_allocation_threads == 0) {
+ hugepage_allocation_threads = num_online_cpus() / 4;
+ hugepage_allocation_threads = max(hugepage_allocation_threads, 1);
+ }
- job.max_threads = num_allocation_threads;
- job.min_chunk = h->max_huge_pages / num_allocation_threads;
+ job.max_threads = hugepage_allocation_threads;
+ job.min_chunk = h->max_huge_pages / hugepage_allocation_threads;
padata_do_multithreaded(&job);
return h->nr_huge_pages;
@@ -5000,6 +5003,28 @@ void __init hugetlb_bootmem_alloc(void)
__hugetlb_bootmem_allocated = true;
}
+/*
+ * hugepage_alloc_threads command line parsing.
+ *
+ * When set, use this specific number of threads for the boot
+ * allocation of hugepages.
+ */
+static int __init hugepage_alloc_threads_setup(char *s)
+{
+ unsigned long allocation_threads;
+
+ if (kstrtoul(s, 0, &allocation_threads) != 0)
+ return 1;
+
+ if (allocation_threads == 0)
+ return 1;
+
+ hugepage_allocation_threads = allocation_threads;
+
+ return 1;
+}
+__setup("hugepage_alloc_threads=", hugepage_alloc_threads_setup);
+
static unsigned int allowed_mems_nr(struct hstate *h)
{
int node;
_
Patches currently in -mm which might be from thomas.prescher@xxxxxxxxxxxxxxxxxxxxx are
