The patch titled
Subject: kfifo: introduce and use kfifo_skip_count()
has been added to the -mm mm-nonmm-unstable branch. Its filename is
kfifo-introduce-and-use-kfifo_skip_count.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kfifo-introduce-and-use-kfifo_skip_count.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: "Jiri Slaby (SUSE)" <jirislaby@xxxxxxxxxx>
Subject: kfifo: introduce and use kfifo_skip_count()
Date: Fri, 23 Feb 2024 12:51:53 +0100
kfifo_skip_count() is an extended version of kfifo_skip(), accepting also
count. This will be useful in the serial code later.
Now, it can be used to implement both kfifo_skip() and
kfifo_dma_out_finish(). In the latter, 'len' only needs to be divided by
'type' size (as it was until now).
And stop using statement expressions when the return value is cast to
'void'. Use classic 'do {} while (0)' instead.
Note: perhaps we should skip 'count' records for the 'recsize' case, but
the original (kfifo_dma_out_finish()) used to skip only one record. So
this is kept unchanged and 'count' is still ignored in the recsize case.
Link: https://lkml.kernel.org/r/20240223115155.8806-3-jirislaby@xxxxxxxxxx
Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx>
Cc: Stefani Seibold <stefani@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/kfifo.h | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)
--- a/include/linux/kfifo.h~kfifo-introduce-and-use-kfifo_skip_count
+++ a/include/linux/kfifo.h
@@ -304,19 +304,25 @@ __kfifo_uint_must_check_helper( \
)
/**
- * kfifo_skip - skip output data
+ * kfifo_skip_count - skip output data
* @fifo: address of the fifo to be used
+ * @count: count of data to skip
*/
-#define kfifo_skip(fifo) \
-(void)({ \
+#define kfifo_skip_count(fifo, count) do { \
typeof((fifo) + 1) __tmp = (fifo); \
const size_t __recsize = sizeof(*__tmp->rectype); \
struct __kfifo *__kfifo = &__tmp->kfifo; \
if (__recsize) \
__kfifo_skip_r(__kfifo, __recsize); \
else \
- __kfifo->out++; \
-})
+ __kfifo->out += (count); \
+} while(0)
+
+/**
+ * kfifo_skip - skip output data
+ * @fifo: address of the fifo to be used
+ */
+#define kfifo_skip(fifo) kfifo_skip_count(fifo, 1)
/**
* kfifo_peek_len - gets the size of the next fifo record
@@ -790,17 +796,10 @@ __kfifo_int_must_check_helper( \
* Note that with only one concurrent reader and one concurrent
* writer, you don't need extra locking to use these macros.
*/
-#define kfifo_dma_out_finish(fifo, len) \
-(void)({ \
+#define kfifo_dma_out_finish(fifo, len) do { \
typeof((fifo) + 1) __tmp = (fifo); \
- unsigned int __len = (len); \
- const size_t __recsize = sizeof(*__tmp->rectype); \
- struct __kfifo *__kfifo = &__tmp->kfifo; \
- if (__recsize) \
- __kfifo_skip_r(__kfifo, __recsize); \
- else \
- __kfifo->out += __len / sizeof(*__tmp->type); \
-})
+ kfifo_skip_count(__tmp, (len) / sizeof(*__tmp->type)); \
+} while (0)
/**
* kfifo_out_peek - gets some data from the fifo
_
Patches currently in -mm which might be from jirislaby@xxxxxxxxxx are
kfifo-drop-__kfifo_dma_out_finish_r.patch
kfifo-introduce-and-use-kfifo_skip_count.patch
kfifo-add-kfifo_out_linear_ptr.patch
kfifo-fix-typos-in-kernel-doc.patch
