From db4632c65eb505410f2e6be9c4d50226c973a129 Mon Sep 17 00:00:00 2001
From: Tor Vic <torvic9@mailbox.org>
Date: Wed, 16 Dec 2020 13:58:02 +0100
Subject: [PATCH] Makefile: use smaller dictionary size for xz module
 compression

By default, xz without parameters uses a dictionary size of 8 MB.
However, most modules are much smaller than that.
The xz manpage states that 'increasing dictionary size usually improves
compression ratio, but a dictionary bigger than the uncompressed file
is waste of memory'.
Use a dictionary size of 2 MB for module compression, resulting in
slightly higher compression speed while still maintaining a good
compression ratio.

Signed-off-by: Tor Vic <torvic9@mailbox.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index ade44ac4cc2ffa..f0cfcc7e0886ff 100644
--- a/Makefile
+++ b/Makefile
@@ -1053,7 +1053,7 @@ ifdef CONFIG_MODULE_COMPRESS
     mod_compress_cmd = $(KGZIP) -n -f
   endif # CONFIG_MODULE_COMPRESS_GZIP
   ifdef CONFIG_MODULE_COMPRESS_XZ
-    mod_compress_cmd = $(XZ) -f
+    mod_compress_cmd = $(XZ) --lzma2=dict=2MiB -f
   endif # CONFIG_MODULE_COMPRESS_XZ
 endif # CONFIG_MODULE_COMPRESS
 export mod_compress_cmd
-- 
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