+ mm-hugetlb-log-time-needed-to-allocate-hugepages.patch added to mm-unstable branch

+ mm-hugetlb-log-time-needed-to-allocate-hugepages.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: hugetlb: log time needed to allocate hugepages
has been added to the -mm mm-unstable branch.  Its filename is
     mm-hugetlb-log-time-needed-to-allocate-hugepages.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-hugetlb-log-time-needed-to-allocate-hugepages.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Thomas Prescher <thomas.prescher@cyberus-technology.de>
Subject: mm: hugetlb: log time needed to allocate hugepages
Date: Thu, 27 Feb 2025 23:45:07 +0100

Having this information allows users to easily tune the
hugepages_node_threads parameter.

Link: https://lkml.kernel.org/r/20250227-hugepage-parameter-v2-3-7db8c6dc0453@cyberus-technology.de
Signed-off-by: Thomas Prescher <thomas.prescher@cyberus-technology.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Muchun Song <muchun.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/hugetlb.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/mm/hugetlb.c~mm-hugetlb-log-time-needed-to-allocate-hugepages
+++ a/mm/hugetlb.c
@@ -3603,6 +3603,9 @@ static unsigned long __init hugetlb_page
 		.numa_aware	= true
 	};
 
+	unsigned long jiffies_start;
+	unsigned long jiffies_end;
+
 	job.thread_fn	= hugetlb_pages_alloc_boot_node;
 	job.start	= 0;
 	job.size	= h->max_huge_pages;
@@ -3630,7 +3633,14 @@ static unsigned long __init hugetlb_page
 
 	job.max_threads	= hugepage_allocation_threads;
 	job.min_chunk	= h->max_huge_pages / hugepage_allocation_threads;
+
+	jiffies_start = jiffies;
 	padata_do_multithreaded(&job);
+	jiffies_end = jiffies;
+
+	pr_info("HugeTLB: allocation took %dms with hugepage_allocation_threads=%ld\n",
+		jiffies_to_msecs(jiffies_end - jiffies_start),
+		hugepage_allocation_threads);
 
 	return h->nr_huge_pages;
 }
_

Patches currently in -mm which might be from thomas.prescher@cyberus-technology.de are

mm-hugetlb-improve-parallel-huge-page-allocation-time.patch
mm-hugetlb-add-hugetlb_alloc_threads-cmdline-option.patch
mm-hugetlb-log-time-needed-to-allocate-hugepages.patch