From a4614bffd786fe06a824f11f2d8602641b3d0e98 Mon Sep 17 00:00:00 2001
From: Ankit Kumar <ankit.kumar@samsung.com>
Date: Wed, 1 Nov 2023 00:15:40 +0530
Subject: [PATCH] crct10: use isa-l for crc if available

isa-l provides fast implementation for various polynomials.
This will be only used for end to end data protection, and has
a significant impact on performance.

See: https://github.com/intel/isa-l

Signed-off-by: Ankit Kumar <ankit.kumar@samsung.com>
---
 HOWTO.rst              |  4 ++++
 configure              | 29 +++++++++++++++++++++++++++++
 crc/crct10dif_common.c | 13 +++++++++++++
 fio.1                  |  4 ++++
 4 files changed, 50 insertions(+)

diff --git a/HOWTO.rst b/HOWTO.rst
index 6a8fb3e3..34d6afdf 100644
--- a/HOWTO.rst
+++ b/HOWTO.rst
@@ -2507,6 +2507,10 @@ with the caveat that when used on the command line, they must come after the
 	If this is set to 0, fio generates protection information for
 	write case and verifies for read case. Default: 1.
 
+	For 16 bit CRC generation fio will use isa-l if available otherwise
+	it will use the default slower generator.
+	(see: https://github.com/intel/isa-l)
+
 .. option:: pi_chk=str[,str][,str] : [io_uring_cmd]
 
 	Controls the protection information check. This can take one or more
diff --git a/configure b/configure
index 3e3f8132..420d97db 100755
--- a/configure
+++ b/configure
@@ -189,6 +189,7 @@ libiscsi="no"
 libnbd="no"
 libnfs=""
 xnvme=""
+isal=""
 libblkio=""
 libzbc=""
 dfs=""
@@ -262,6 +263,8 @@ for opt do
   ;;
   --disable-xnvme) xnvme="no"
   ;;
+  --disable-isal) isal="no"
+  ;;
   --disable-libblkio) libblkio="no"
   ;;
   --disable-tcmalloc) disable_tcmalloc="yes"
@@ -322,6 +325,7 @@ if test "$show_help" = "yes" ; then
   echo "--enable-libiscsi       Enable iscsi support"
   echo "--enable-libnbd         Enable libnbd (NBD engine) support"
   echo "--disable-xnvme         Disable xnvme support even if found"
+  echo "--disable-isal          Disable isal support even if found"
   echo "--disable-libblkio      Disable libblkio support even if found"
   echo "--disable-libzbc        Disable libzbc even if found"
   echo "--disable-tcmalloc      Disable tcmalloc support"
@@ -2684,6 +2688,28 @@ if test "$xnvme" != "no" ; then
 fi
 print_config "xnvme engine" "$xnvme"
 
+if test "$targetos" = "Linux" ; then
+##########################################
+# Check ISA-L support
+cat > $TMPC << EOF
+#include <isa-l/crc.h>
+#include <stddef.h>
+int main(void)
+{
+  return crc16_t10dif(0, NULL, 4096);
+}
+EOF
+if test "$isal" != "no" ; then
+  if compile_prog "" "-lisal" "ISAL"; then
+    isal="yes"
+    LIBS="-lisal $LIBS"
+  else
+    isal="no"
+  fi
+fi
+print_config "isal" "$isal"
+fi
+
 ##########################################
 # Check if we have libblkio
 if test "$libblkio" != "no" ; then
@@ -3334,6 +3360,9 @@ if test "$xnvme" = "yes" ; then
   echo "LIBXNVME_CFLAGS=$xnvme_cflags" >> $config_host_mak
   echo "LIBXNVME_LIBS=$xnvme_libs" >> $config_host_mak
 fi
+if test "$isal" = "yes" ; then
+  output_sym "CONFIG_LIBISAL"
+fi
 if test "$libblkio" = "yes" ; then
   output_sym "CONFIG_LIBBLKIO"
   echo "LIBBLKIO_CFLAGS=$libblkio_cflags" >> $config_host_mak
diff --git a/crc/crct10dif_common.c b/crc/crct10dif_common.c
index cfb2a1b1..1763b1c6 100644
--- a/crc/crct10dif_common.c
+++ b/crc/crct10dif_common.c
@@ -24,6 +24,17 @@
  *
  */
 
+#ifdef CONFIG_LIBISAL
+#include <isa-l/crc.h>
+
+extern unsigned short fio_crc_t10dif(unsigned short crc,
+				     const unsigned char *buffer,
+				     unsigned int len)
+{
+	return crc16_t10dif(crc, buffer, len);
+}
+
+#else
 #include "crc-t10dif.h"
 
 /* Table generated using the following polynomium:
@@ -76,3 +87,5 @@ extern unsigned short fio_crc_t10dif(unsigned short crc,
 
 	return crc;
 }
+
+#endif
diff --git a/fio.1 b/fio.1
index a8dc8f6c..c4742aa9 100644
--- a/fio.1
+++ b/fio.1
@@ -2263,6 +2263,10 @@ size greater than protection information size, fio will not generate or verify
 the protection information portion of metadata for write or read case
 respectively. If this is set to 0, fio generates protection information for
 write case and verifies for read case. Default: 1.
+
+For 16 bit CRC generation fio will use isa-l if available otherwise it will
+use the default slower generator.
+(see: https://github.com/intel/isa-l)
 .TP
 .BI (io_uring_cmd)pi_chk \fR=\fPstr[,str][,str]
 Controls the protection information check. This can take one or more of these
-- 
2.25.1