commit 733285fea265af4fc91cf37916fada1a66cec470
author Alistair Strachan <alistair.strachan@imgtec.com> Thu May 05 16:04:32 2016 -0700
committer Alistair Strachan <alistair.strachan@imgtec.com> Thu May 05 16:04:58 2016 -0700
tree b8ffdee0dae6d2e577436533e59bf00eed021d63
parent ecd6e2af5060ba3f7d5c978be6d617d1242f231c

updater, minzip: Remove unnecessary O_SYNC flags.

Remove O_SYNC from mzExtractRecursive() and PackageExtractFileFn().
These functions deal with extracting whole files from the update
package onto a filesystem. If run on ext4 on a rotating disk, for
example, the O_SYNC flag will cause serious performance problems
and the extraction proecss can take over 30 minutes, with no
obvious benefits.

This API function already calls fsync(fd) after each file is
extracted to ensure data and metadata is written to the underlying
block device, so the O_SYNC calls should be superfluous and safely
removable.

This change does not affect the OTA patch paths or any modification
of the bootloader partition or writes to other 'emmc' partitions.

Signed-off-by: Alistair Strachan <alistair.strachan@imgtec.com>
Change-Id: I9cbb98a98e6278bf5c0d7efaae340773d1fbfcd2

minzip/Zip.c

diff --git a/minzip/Zip.c b/minzip/Zip.c
index 9f550f8..d557daa 100644
--- a/minzip/Zip.c
+++ b/minzip/Zip.c
@@ -968,7 +968,7 @@
                 setfscreatecon(secontext);
             }
 
-            int fd = open(targetFile, O_CREAT|O_WRONLY|O_TRUNC|O_SYNC,
+            int fd = open(targetFile, O_CREAT|O_WRONLY|O_TRUNC,
                 UNZIP_FILEMODE);
 
             if (secontext) {

updater/install.cpp

diff --git a/updater/install.cpp b/updater/install.cpp
index 4f52684..bab2fe1 100644
--- a/updater/install.cpp
+++ b/updater/install.cpp
@@ -559,7 +559,7 @@
         }
 
         {
-            int fd = TEMP_FAILURE_RETRY(ota_open(dest_path, O_WRONLY | O_CREAT | O_TRUNC | O_SYNC,
+            int fd = TEMP_FAILURE_RETRY(ota_open(dest_path, O_WRONLY | O_CREAT | O_TRUNC,
                   S_IRUSR | S_IWUSR));
             if (fd == -1) {
                 printf("%s: can't open %s for write: %s\n", name, dest_path, strerror(errno));