The patch titled
Subject: xarray: extract helper from __xa_{insert,cmpxchg}
has been added to the -mm mm-nonmm-unstable branch. Its filename is
xarray-extract-helper-from-__xa_insertcmpxchg.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/xarray-extract-helper-from-__xa_insertcmpxchg.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Tamir Duberstein <tamird@xxxxxxxxx>
Subject: xarray: extract helper from __xa_{insert,cmpxchg}
Date: Tue, 12 Nov 2024 14:25:37 -0500
Reduce code duplication by extracting a static inline function. This
function is identical to __xa_cmpxchg with the exception that it does not
coerce zero entries to null on the return path.
Link: https://lkml.kernel.org/r/20241112-xarray-insert-cmpxchg-v1-2-dc2bdd8c4136@xxxxxxxxx
Signed-off-by: Tamir Duberstein <tamird@xxxxxxxxx>
Cc: Alice Ryhl <aliceryhl@xxxxxxxxxx>
Cc: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/xarray.c | 37 ++++++++++++++++++-------------------
1 file changed, 18 insertions(+), 19 deletions(-)
--- a/lib/xarray.c~xarray-extract-helper-from-__xa_insertcmpxchg
+++ a/lib/xarray.c
@@ -1491,7 +1491,7 @@ static void *xas_result(struct xa_state
{
if (xas_error(xas))
curr = xas->xa_node;
- return xa_zero_to_null(curr);
+ return curr;
}
/**
@@ -1568,7 +1568,7 @@ void *__xa_store(struct xarray *xa, unsi
xas_clear_mark(&xas, XA_FREE_MARK);
} while (__xas_nomem(&xas, gfp));
- return xas_result(&xas, curr);
+ return xas_result(&xas, xa_zero_to_null(curr));
}
EXPORT_SYMBOL(__xa_store);
@@ -1601,6 +1601,9 @@ void *xa_store(struct xarray *xa, unsign
}
EXPORT_SYMBOL(xa_store);
+static inline void *__xa_cmpxchg_raw(struct xarray *xa, unsigned long index,
+ void *old, void *entry, gfp_t gfp);
+
/**
* __xa_cmpxchg() - Store this entry in the XArray.
* @xa: XArray.
@@ -1620,6 +1623,13 @@ EXPORT_SYMBOL(xa_store);
void *__xa_cmpxchg(struct xarray *xa, unsigned long index,
void *old, void *entry, gfp_t gfp)
{
+ return xa_zero_to_null(__xa_cmpxchg_raw(xa, index, old, entry, gfp));
+}
+EXPORT_SYMBOL(__xa_cmpxchg);
+
+static inline void *__xa_cmpxchg_raw(struct xarray *xa, unsigned long index,
+ void *old, void *entry, gfp_t gfp)
+{
XA_STATE(xas, xa, index);
void *curr;
@@ -1637,7 +1647,6 @@ void *__xa_cmpxchg(struct xarray *xa, un
return xas_result(&xas, curr);
}
-EXPORT_SYMBOL(__xa_cmpxchg);
/**
* __xa_insert() - Store this entry in the XArray if no entry is present.
@@ -1657,26 +1666,16 @@ EXPORT_SYMBOL(__xa_cmpxchg);
*/
int __xa_insert(struct xarray *xa, unsigned long index, void *entry, gfp_t gfp)
{
- XA_STATE(xas, xa, index);
void *curr;
+ int errno;
- if (WARN_ON_ONCE(xa_is_advanced(entry)))
- return -EINVAL;
if (!entry)
entry = XA_ZERO_ENTRY;
-
- do {
- curr = xas_load(&xas);
- if (!curr) {
- xas_store(&xas, entry);
- if (xa_track_free(xa))
- xas_clear_mark(&xas, XA_FREE_MARK);
- } else {
- xas_set_err(&xas, -EBUSY);
- }
- } while (__xas_nomem(&xas, gfp));
-
- return xas_error(&xas);
+ curr = __xa_cmpxchg_raw(xa, index, NULL, entry, gfp);
+ errno = xa_err(curr);
+ if (errno)
+ return errno;
+ return (curr != NULL) ? -EBUSY : 0;
}
EXPORT_SYMBOL(__xa_insert);
_
Patches currently in -mm which might be from tamird@xxxxxxxxx are
xarray-extract-xa_zero_to_null.patch
xarray-extract-helper-from-__xa_insertcmpxchg.patch
