Linux RAID subsystem development
 help / color / mirror / Atom feed
From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
To: Andrew Morton <akpm@linux-foundation.org>,
	Song Liu <song@kernel.org>,  Yu Kuai <yukuai@fnnas.com>,
	Li Nan <linan122@huawei.com>,  Xiao Ni <xiao@kernel.org>
Cc: David Laight <david.laight.linux@gmail.com>,
	 Mike Rapoport <rppt@kernel.org>,
	linux-kernel@vger.kernel.org,  linux-mm@kvack.org,
	linux-raid@vger.kernel.org
Subject: [PATCH v2 1/2] lib/raid: use kvmalloc() in calibrate_xor_blocks()
Date: Tue, 26 May 2026 15:50:38 +0300	[thread overview]
Message-ID: <20260526-lib-v2-1-ca3f0fc24b14@kernel.org> (raw)
In-Reply-To: <20260526-lib-v2-0-ca3f0fc24b14@kernel.org>

The xor benchmark allocates an order 2 (4 pages) scratch buffer that is
used purely as a CPU-only XOR working area.

This buffer does not need to be physically contiguous and can be
allocated with kvmalloc().

Replace __get_free_pages() call with kvmalloc().

Link: https://lore.kernel.org/all/635405e4-9423-4a25-a6e7-e03c8ea0bcbe@redhat.com
Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
---
 lib/raid/xor/xor-core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/raid/xor/xor-core.c b/lib/raid/xor/xor-core.c
index bd4e6e434418..9f90620617cd 100644
--- a/lib/raid/xor/xor-core.c
+++ b/lib/raid/xor/xor-core.c
@@ -8,6 +8,7 @@
 
 #include <linux/module.h>
 #include <linux/gfp.h>
+#include <linux/slab.h>
 #include <linux/raid/xor.h>
 #include <linux/jiffies.h>
 #include <linux/preempt.h>
@@ -114,7 +115,7 @@ static int __init calibrate_xor_blocks(void)
 	if (forced_template)
 		return 0;
 
-	b1 = (void *) __get_free_pages(GFP_KERNEL, 2);
+	b1 = kvmalloc(PAGE_SIZE * 4, GFP_KERNEL);
 	if (!b1) {
 		pr_warn("xor: Yikes!  No memory available.\n");
 		return -ENOMEM;
@@ -132,7 +133,7 @@ static int __init calibrate_xor_blocks(void)
 	pr_info("xor: using function: %s (%d MB/sec)\n",
 	       fastest->name, fastest->speed);
 
-	free_pages((unsigned long)b1, 2);
+	kvfree(b1);
 	return 0;
 }
 

-- 
2.53.0


  reply	other threads:[~2026-05-26 12:50 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-05-26 12:50 [PATCH v2 0/2] lib/raid: replace __get_free_pages() call with kvmalloc() Mike Rapoport (Microsoft)
2026-05-26 12:50 ` Mike Rapoport (Microsoft) [this message]
2026-05-27  7:32   ` [PATCH v2 1/2] lib/raid: use kvmalloc() in calibrate_xor_blocks() Christoph Hellwig
2026-05-26 12:50 ` [PATCH v2 2/2] lib/raid6: use kvmalloc() in raid6_select_algo() Mike Rapoport (Microsoft)
2026-05-26 17:34   ` Andrew Morton
2026-05-27  6:38     ` Christoph Hellwig
2026-05-27 11:28       ` Mike Rapoport
2026-05-27  7:33   ` Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260526-lib-v2-1-ca3f0fc24b14@kernel.org \
    --to=rppt@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=david.laight.linux@gmail.com \
    --cc=linan122@huawei.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-raid@vger.kernel.org \
    --cc=song@kernel.org \
    --cc=xiao@kernel.org \
    --cc=yukuai@fnnas.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox