Avoids the following warnings from sparse:
visorchannel_funcs.c:457:9: warning:
context imbalance in 'visorchannel_signalremove' - different lock contexts for basic block
visorchannel_funcs.c:512:9: warning:
context imbalance in 'visorchannel_signalinsert' - different lock contexts for basic
These warnings are false positives. Sparse can't track conditional contexts. The change
puts the lock/unlock into the same context by splitting the insert/remove functions each
into a wrapper function that does locking if necessary and an inner function that does the
insert/remove operation.
Signed-off-by: Zachary Warren <conflatulence@xxxxxxxxx>
---
Diff generated against next-20150116.
Change from v1:
- Replace the link in the changelog with words.
.../unisys/visorchannel/visorchannel_funcs.c | 103 +++++++++++----------
1 file changed, 54 insertions(+), 49 deletions(-)
diff --git a/drivers/staging/unisys/visorchannel/visorchannel_funcs.c b/drivers/staging/unisys/visorchannel/visorchannel_funcs.c
index 6c48ba1..0188ef8 100644
--- a/drivers/staging/unisys/visorchannel/visorchannel_funcs.c
+++ b/drivers/staging/unisys/visorchannel/visorchannel_funcs.c
@@ -411,27 +411,21 @@ safe_sig_queue_validate(struct signal_queue_header *psafe_sqh,
return 1;
} /* end safe_sig_queue_validate */
-BOOL
-visorchannel_signalremove(struct visorchannel *channel, u32 queue, void *msg)
+static BOOL
+signalremove_inner(struct visorchannel *channel, u32 queue, void *msg)
{
- BOOL rc = FALSE;
struct signal_queue_header sig_hdr;
- if (channel->needs_lock)
- spin_lock(&channel->remove_lock);
-
if (!sig_read_header(channel, queue, &sig_hdr)) {
- rc = FALSE;
- goto cleanup;
- }
- if (sig_hdr.head == sig_hdr.tail) {
- rc = FALSE; /* no signals to remove */
- goto cleanup;
+ return FALSE;
}
+ if (sig_hdr.head == sig_hdr.tail)
+ return FALSE; /* no signals to remove */
+
sig_hdr.tail = (sig_hdr.tail + 1) % sig_hdr.max_slots;
if (!sig_read_data(channel, queue, &sig_hdr, sig_hdr.tail, msg)) {
- ERRDRV("sig_read_data failed: (status=%d)\n", rc);
- goto cleanup;
+ ERRDRV("sig_read_data failed\n");
+ return FALSE;
}
sig_hdr.num_received++;
@@ -440,53 +434,54 @@ visorchannel_signalremove(struct visorchannel *channel, u32 queue, void *msg)
*/
mb(); /* required for channel synch */
if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, tail)) {
- ERRDRV("visor_memregion_write of Tail failed: (status=%d)\n",
- rc);
- goto cleanup;
+ ERRDRV("visor_memregion_write of Tail failed\n");
+ return FALSE;
}
if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, num_received)) {
- ERRDRV("visor_memregion_write of NumSignalsReceived failed: (status=%d)\n",
- rc);
- goto cleanup;
+ ERRDRV("visor_memregion_write of NumSignalsReceived failed\n");
+ return FALSE;
}
- rc = TRUE;
-cleanup:
- if (channel->needs_lock)
+ return TRUE;
+}
+
+BOOL
+visorchannel_signalremove(struct visorchannel *channel, u32 queue, void *msg)
+{
+ BOOL rc;
+
+ if (channel->needs_lock) {
+ spin_lock(&channel->remove_lock);
+ rc = signalremove_inner(channel, queue, msg);
spin_unlock(&channel->remove_lock);
+ } else {
+ rc = signalremove_inner(channel, queue, msg);
+ }
return rc;
}
EXPORT_SYMBOL_GPL(visorchannel_signalremove);
-BOOL
-visorchannel_signalinsert(struct visorchannel *channel, u32 queue, void *msg)
+static BOOL
+signalinsert_inner(struct visorchannel *channel, u32 queue, void *msg)
{
- BOOL rc = FALSE;
struct signal_queue_header sig_hdr;
- if (channel->needs_lock)
- spin_lock(&channel->insert_lock);
-
if (!sig_read_header(channel, queue, &sig_hdr)) {
- rc = FALSE;
- goto cleanup;
+ return FALSE;
}
sig_hdr.head = ((sig_hdr.head + 1) % sig_hdr.max_slots);
if (sig_hdr.head == sig_hdr.tail) {
sig_hdr.num_overflows++;
- if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, num_overflows)) {
- ERRDRV("visor_memregion_write of NumOverflows failed: (status=%d)\n",
- rc);
- goto cleanup;
- }
- rc = FALSE;
- goto cleanup;
+ if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, num_overflows))
+ ERRDRV("visor_memregion_write of NumOverflows failed\n");
+
+ return FALSE;
}
if (!sig_write_data(channel, queue, &sig_hdr, sig_hdr.head, msg)) {
- ERRDRV("sig_write_data failed: (status=%d)\n", rc);
- goto cleanup;
+ ERRDRV("sig_write_data failed\n");
+ return FALSE;
}
sig_hdr.num_sent++;
@@ -495,19 +490,29 @@ visorchannel_signalinsert(struct visorchannel *channel, u32 queue, void *msg)
*/
mb(); /* required for channel synch */
if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, head)) {
- ERRDRV("visor_memregion_write of Head failed: (status=%d)\n",
- rc);
- goto cleanup;
+ ERRDRV("visor_memregion_write of Head failed\n");
+ return FALSE;
}
if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, num_sent)) {
- ERRDRV("visor_memregion_write of NumSignalsSent failed: (status=%d)\n",
- rc);
- goto cleanup;
+ ERRDRV("visor_memregion_write of NumSignalsSent failed\n");
+ return FALSE;
}
- rc = TRUE;
-cleanup:
- if (channel->needs_lock)
+
+ return TRUE;
+}
+
+BOOL
+visorchannel_signalinsert(struct visorchannel *channel, u32 queue, void *msg)
+{
+ BOOL rc;
+
+ if (channel->needs_lock) {
+ spin_lock(&channel->insert_lock);
+ rc = signalinsert_inner(channel, queue, msg);
spin_unlock(&channel->insert_lock);
+ } else {
+ rc = signalinsert_inner(channel, queue, msg);
+ }
return rc;
}
--
2.1.0
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