[PATCH] lib/xxhash: Comment out unused functions

From: linux
Date: Sun Jul 13 2025 - 20:09:43 EST


From: "Dr. David Alan Gilbert" <linux@xxxxxxxxxxx>

xxh32_digest() and xxh32_update() were added in 2017 in the original
xxhash commit, but have remained unused.

While I've mostly been deleting unused functions, this is a general
library and I see erofs is using other bits of xxh32, so it didn't
seem right just to delete them.

Comment them out with #if 0.
(Which checkpatch rightly warns about)

Signed-off-by: Dr. David Alan Gilbert <linux@xxxxxxxxxxx>
---
include/linux/xxhash.h | 4 ++++
lib/xxhash.c | 2 ++
2 files changed, 6 insertions(+)

diff --git a/include/linux/xxhash.h b/include/linux/xxhash.h
index df42511438d0..46d513a0212a 100644
--- a/include/linux/xxhash.h
+++ b/include/linux/xxhash.h
@@ -177,6 +177,9 @@ struct xxh64_state {
*/
void xxh32_reset(struct xxh32_state *state, uint32_t seed);

+#if 0
+/* Currently unused, feel free to uncomment them if you use them. */
+
/**
* xxh32_update() - hash the data given and update the xxh32 state
*
@@ -202,6 +205,7 @@ int xxh32_update(struct xxh32_state *state, const void *input, size_t length);
* Return: The xxh32 hash stored in the state.
*/
uint32_t xxh32_digest(const struct xxh32_state *state);
+#endif

/**
* xxh64_reset() - reset the xxh64 state to start a new hashing operation
diff --git a/lib/xxhash.c b/lib/xxhash.c
index b5bd567aa6b3..988a22e9a139 100644
--- a/lib/xxhash.c
+++ b/lib/xxhash.c
@@ -267,6 +267,7 @@ void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed)
}
EXPORT_SYMBOL(xxh64_reset);

+#if 0
int xxh32_update(struct xxh32_state *state, const void *input, const size_t len)
{
const uint8_t *p = (const uint8_t *)input;
@@ -373,6 +374,7 @@ uint32_t xxh32_digest(const struct xxh32_state *state)
return h32;
}
EXPORT_SYMBOL(xxh32_digest);
+#endif

int xxh64_update(struct xxh64_state *state, const void *input, const size_t len)
{
--
2.50.1