Added raid6 preselected algorithm patch.

Anyone that uses raid6 and has avx2 should change it to avx2x4.

3 files changed, 81 insertions, 2 deletions

diff --git a/PKGBUILD b/PKGBUILD
index 56a6d65..75506e9 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -6,7 +6,7 @@
 
 # # I maintain this because:
 # Arch version patch script does not apply consistently
-# Arch version lacks ath9k and greysky2 patches
+# Arch version lacks ath9k, greysky2, and raid6 patches
 # Arch version allows SM3 and SM4
 # Arch version is 300 Hz
 # Arch version supports Intel ME
@@ -31,6 +31,7 @@ source=(https://www.kernel.org/pub/linux/kernel/v4.x/linux-${pkgver}.tar.xz
         https://www.kernel.org/pub/linux/kernel/v4.x/linux-${pkgver}.tar.sign
         enable_additional_cpu_optimizations-$_gcc_more_v.tar.gz::https://github.com/graysky2/kernel_gcc_patch/archive/$_gcc_more_v.tar.gz
         ath9k-regdom-hack.patch
+        raid6-default-algo.patch
         config.x86_64  # the main kernel config files
         60-linux.hook  # pacman hook for depmod
         90-linux.hook  # pacman hook for initramfs regeneration
@@ -40,7 +41,8 @@ sha256sums=('53de6be9adfb8899f0a15855f1aef62b8b5a3c5c575196ec8a640a5b8c1c3cf8'
             'SKIP'
             '226e30068ea0fecdb22f337391385701996bfbdba37cdcf0f1dbf55f1080542d'
             'e7ebf050c22bcec0028c0b3c79fd6d3913b0370ecc6a23dfe78ce475630cf503'
-            '0de5efb4e997d0aeb7c4a16997da39100e91a7e335ac00b2d7d951bc675fe538'
+            '0f81d6e4158b7beeb0eb514f1b9401f7e23699cb0f7b0d513e25dae1815daaeb'
+            '77bd79791cbfc91d4e62a77245e7e784e6978cbadb4450cb1a611a68944b84aa'
             'ae2e95db94ef7176207c690224169594d49445e04249d2499e9d2fbc117a0b21'
             '75f99f5239e03238f88d1a834c50043ec32b1dc568f2cc291b07d04718483919'
             'ad6344badc91ad0630caacde83f7f9b97276f80d26a20619a87952be65492c65')
@@ -70,6 +72,10 @@ prepare() {
   msg2 "Applying ath9k patch"
   patch -p1 -i ../ath9k-regdom-hack.patch
 
+  # Set default raid6 algo patch
+  msg " Applying raid6 patch"
+  patch -p1 -i ../raid6-default-algo.patch
+
 
   msg2 "Setting version..."
   scripts/setlocalversion --save-scmversion
@@ -84,6 +90,7 @@ prepare() {
   #else
     cp ../config.x86_64 .config
   #fi
+
   make olddefconfig
 
   make menuconfig
diff --git a/config.x86_64 b/config.x86_64
index 8bbd317..240ebb2 100644
--- a/config.x86_64
+++ b/config.x86_64
@@ -9499,6 +9499,8 @@ CONFIG_BINARY_PRINTF=y
 # Library routines
 #
 CONFIG_RAID6_PQ=m
+CONFIG_RAID6_PQ_DEFAULT_ALG_BOOL=y
+CONFIG_RAID6_PQ_DEFAULT_ALG="sse2x4"
 CONFIG_BITREVERSE=y
 CONFIG_RATIONAL=y
 CONFIG_GENERIC_STRNCPY_FROM_USER=y
diff --git a/raid6-default-algo.patch b/raid6-default-algo.patch
new file mode 100644
index 0000000..98bfd54
--- /dev/null
+++ b/raid6-default-algo.patch
@@ -0,0 +1,70 @@
+--- a/lib/Kconfig
++++ b/lib/Kconfig
+@@ -10,6 +10,23 @@ menu "Library routines"
+ config RAID6_PQ
+ 	tristate
+ 
++config RAID6_PQ_DEFAULT_ALG_BOOL
++	bool "Default RAID6 PQ algorithm"
++	default n
++	depends on RAID6_PQ
++	help
++	  Allow for specifying a default algorithm via the kernel
++	  parameter "raid6_pq_default_alg", which forces the performance
++	  tests to be skipped. This can save between 500ms to 2s
++	  during boot.
++
++config RAID6_PQ_DEFAULT_ALG
++	string "Default RAID6 PQ algorithm name"
++	default ""
++	depends on RAID6_PQ_DEFAULT_ALG_BOOL
++	help
++	  The default algorithm name to be used by default.
++
+ config BITREVERSE
+ 	tristate
+ 
+diff --git a/lib/raid6/algos.c b/lib/raid6/algos.c
+index d3b16f43c39f..480cbfbe293f 100644
+--- a/lib/raid6/algos.c
++++ b/lib/raid6/algos.c
+@@ -30,6 +30,12 @@ EXPORT_SYMBOL(raid6_empty_zero_page);
+ #endif
+ #endif
+ 
++#ifdef CONFIG_RAID6_PQ_DEFAULT_ALG_BOOL
++static char raid6_pq_default_alg[32] = CONFIG_RAID6_PQ_DEFAULT_ALG;
++module_param_string(raid6_pq_default_alg, raid6_pq_default_alg, sizeof(raid6_pq_default_alg), 0444);
++MODULE_PARM_DESC(raid6_pq_default_alg, "Default gen/xor() algorithm");
++#endif
++
+ struct raid6_calls raid6_call;
+ EXPORT_SYMBOL_GPL(raid6_call);
+ 
+@@ -157,6 +163,26 @@ static inline const struct raid6_calls *raid6_choose_gen(
+ 	const struct raid6_calls *const *algo;
+ 	const struct raid6_calls *best;
+ 
++#ifdef CONFIG_RAID6_PQ_DEFAULT_ALG_BOOL
++	if (strlen(raid6_pq_default_alg)) {
++		for (algo = raid6_algos; *algo; algo++) {
++			if (!strncmp(raid6_pq_default_alg, (*algo)->name, sizeof(raid6_pq_default_alg))) {
++				if ((*algo)->valid && !(*algo)->valid()) {
++					pr_info("raid6: default alg \"%s\" is invalid.\n",
++						raid6_pq_default_alg);
++					continue;
++				}
++				pr_info("raid6: using default algorithm %s gen() without performace tests.\n",
++					(*algo)->name);
++				raid6_call = **algo;
++				return *algo;
++			}
++		}
++		pr_info("raid6: default alg \"%s\" not found. Choosing the best alg as fallback...\n",
++			raid6_pq_default_alg);
++	}
++#endif
++
+ 	for (bestgenperf = 0, bestxorperf = 0, best = NULL, algo = raid6_algos; *algo; algo++) {
+ 		if (!best || (*algo)->prefer >= best->prefer) {
+ 			/* 2 ^ (RAID6_TIME_JIFFIES_LG2 - 0.5) */