Move the atomic context detection logic from erofs's z_erofs_in_atomic()
into the block layer as bio_in_atomic(). This helper returns true when
the current context is unsafe for sleeping bio completion handlers (e.g.,
hard/soft IRQ, preempt-disabled).
The logic was originally added to erofs in commit c99fab6e80b7 ("erofs:
fix atomic context detection when !CONFIG_DEBUG_LOCK_ALLOC"). A
subsequent patch will use it in the block layer's bio completion
infrastructure, so move it to include/linux/bio.h where both subsystems
can share it.
Convert erofs to call the new bio_in_atomic() directly.
Suggested-by: Christoph Hellwig <[email protected]>
Signed-off-by: Tal Zussman <[email protected]>
---
fs/erofs/zdata.c | 11 +----------
include/linux/bio.h | 15 +++++++++++++++
2 files changed, 16 insertions(+), 10 deletions(-)
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 74520e910259..f796bb3ef53b 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1427,15 +1427,6 @@ static void z_erofs_decompressqueue_kthread_work(struct
kthread_work *work)
}
#endif
-/* Use (kthread_)work in atomic contexts to minimize scheduling overhead */
-static inline bool z_erofs_in_atomic(void)
-{
- if (IS_ENABLED(CONFIG_PREEMPTION) && rcu_preempt_depth())
- return true;
- if (!IS_ENABLED(CONFIG_PREEMPT_COUNT))
- return true;
- return !preemptible();
-}
static void z_erofs_decompress_kickoff(struct z_erofs_decompressqueue *io,
int bios)
@@ -1452,7 +1443,7 @@ static void z_erofs_decompress_kickoff(struct
z_erofs_decompressqueue *io,
if (atomic_add_return(bios, &io->pending_bios))
return;
- if (z_erofs_in_atomic()) {
+ if (bio_in_atomic()) {
/* See `sync_decompress` in sysfs-fs-erofs for more details */
if (sbi->sync_decompress == EROFS_SYNC_DECOMPRESS_AUTO)
sbi->sync_decompress = EROFS_SYNC_DECOMPRESS_FORCE_ON;
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 8f33f717b14f..62a983758e09 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -368,6 +368,21 @@ static inline struct bio *bio_alloc(struct block_device
*bdev,
void submit_bio(struct bio *bio);
+/**
+ * bio_in_atomic - check if the current context is unsafe for bio completion
+ *
+ * Return: %true in atomic contexts (e.g. hard/soft IRQ, preempt-disabled);
+ * %false when a bio can be safely completed in the current context.
+ */
+static inline bool bio_in_atomic(void)
+{
+ if (IS_ENABLED(CONFIG_PREEMPTION) && rcu_preempt_depth())
+ return true;
+ if (!IS_ENABLED(CONFIG_PREEMPT_COUNT))
+ return true;
+ return !preemptible();
+}
+
extern void bio_endio(struct bio *);
/**
--
2.39.5
