[PATCH 11/19] raid6: use static_call for gen_syndrom and xor_syndrom

[Christoph Hellwig]

Avoid indirect calls for P/Q parity generation.

Signed-off-by: Christoph Hellwig <h...@lst.de>
---
 lib/raid/raid6/algos.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/lib/raid/raid6/algos.c b/lib/raid/raid6/algos.c
index 5bd953032e55..65b75236ecf8 100644
--- a/lib/raid/raid6/algos.c
+++ b/lib/raid/raid6/algos.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/gfp.h>
 #include <linux/raid/pq.h>
+#include <linux/static_call.h>
 #include <kunit/visibility.h>
 #include "algos.h"
 
@@ -23,7 +24,8 @@ static unsigned int raid6_nr_algos;
 static const struct raid6_recov_calls *raid6_recov_algo;
 
 /* Selected algorithm */
-static struct raid6_calls raid6_call;
+DEFINE_STATIC_CALL_NULL(raid6_gen_syndrome_impl, *raid6_intx1.gen_syndrome);
+DEFINE_STATIC_CALL_NULL(raid6_xor_syndrome_impl, *raid6_intx1.xor_syndrome);
 
 /**
  * raid6_gen_syndrome - generate RAID6 P/Q parity
@@ -48,7 +50,7 @@ void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs)
        WARN_ON_ONCE(bytes & 511);
        WARN_ON_ONCE(disks < RAID6_MIN_DISKS);
 
-       raid6_call.gen_syndrome(disks, bytes, ptrs);
+       static_call(raid6_gen_syndrome_impl)(disks, bytes, ptrs);
 }
 EXPORT_SYMBOL_GPL(raid6_gen_syndrome);
 
@@ -85,7 +87,7 @@ void raid6_xor_syndrome(int disks, int start, int stop, 
size_t bytes,
        WARN_ON_ONCE(disks < RAID6_MIN_DISKS);
        WARN_ON_ONCE(stop < start);
 
-       raid6_call.xor_syndrome(disks, start, stop, bytes, ptrs);
+       static_call(raid6_xor_syndrome_impl)(disks, start, stop, bytes, ptrs);
 }
 EXPORT_SYMBOL_GPL(raid6_xor_syndrome);
 
@@ -96,7 +98,7 @@ EXPORT_SYMBOL_GPL(raid6_xor_syndrome);
  */
 bool raid6_can_xor_syndrome(void)
 {
-       return !!raid6_call.xor_syndrome;
+       return !!static_call_query(raid6_xor_syndrome_impl);
 }
 EXPORT_SYMBOL_GPL(raid6_can_xor_syndrome);
 
@@ -195,7 +197,8 @@ static int raid6_choose_gen(void *(*const 
dptrs)[RAID6_TEST_DISKS],
                return -EINVAL;
        }
 
-       raid6_call = *best;
+       static_call_update(raid6_gen_syndrome_impl, best->gen_syndrome);
+       static_call_update(raid6_xor_syndrome_impl, best->xor_syndrome);
 
        pr_info("raid6: using algorithm %s gen() %ld MB/s\n",
                best->name,
@@ -240,7 +243,10 @@ static int __init raid6_select_algo(void)
        if (!IS_ENABLED(CONFIG_RAID6_PQ_BENCHMARK) || raid6_nr_algos == 1) {
                pr_info("raid6: skipped pq benchmark and selected %s\n",
                        raid6_algos[raid6_nr_algos - 1]->name);
-               raid6_call = *raid6_algos[raid6_nr_algos - 1];
+               static_call_update(raid6_gen_syndrome_impl,
+                               raid6_algos[raid6_nr_algos - 1]->gen_syndrome);
+               static_call_update(raid6_xor_syndrome_impl,
+                               raid6_algos[raid6_nr_algos - 1]->xor_syndrome);
                return 0;
        }
 
-- 
2.53.0