From ba858e8cd99fbc9e1657a9bd3b3d5926691c2359 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Thu, 24 Feb 2022 12:41:33 +1100 Subject: [PATCH] agent: Don't attempt to create directories for hugepage configuration MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit allocate_hugepages() constructs the path for the sysfs directory containing hugepage configuration, then attempts to create this directory if it does not exist. This doesn't make sense: sysfs is a view into kernel configuration, if the kernel has support for the hugepage size, the directory will already be there, if it doesn't, trying to create it won't help. For the same reason, attempting to create the "nr_hugepages" file itself is pointless, so there's no reason to call OpenOptions::create(true). Signed-off-by: David Gibson (cherry picked from commit 608e003abcf7ce54c12512d79b5196b74c1883db) Signed-off-by: Fabiano Fidêncio --- src/agent/src/mount.rs | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/src/agent/src/mount.rs b/src/agent/src/mount.rs index fbead0953a..e788e18dff 100644 --- a/src/agent/src/mount.rs +++ b/src/agent/src/mount.rs @@ -321,20 +321,16 @@ fn allocate_hugepages(logger: &Logger, options: &[String]) -> Result<()> { // sysfs entry is always of the form hugepages-${pagesize}kB // Ref: https://www.kernel.org/doc/Documentation/vm/hugetlbpage.txt - let path = Path::new(SYS_FS_HUGEPAGES_PREFIX).join(format!("hugepages-{}kB", pagesize / 1024)); - - if !path.exists() { - fs::create_dir_all(&path).context("create hugepages-size directory")?; - } + let path = Path::new(SYS_FS_HUGEPAGES_PREFIX) + .join(format!("hugepages-{}kB", pagesize / 1024)) + .join("nr_hugepages"); // write numpages to nr_hugepages file. - let path = path.join("nr_hugepages"); let numpages = format!("{}", size / pagesize); info!(logger, "write {} pages to {:?}", &numpages, &path); let mut file = OpenOptions::new() .write(true) - .create(true) .open(&path) .context(format!("open nr_hugepages directory {:?}", &path))?;