On 9/23/20 6:56 AM, Stefan Hajnoczi wrote:
clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:
$ CC=clang CXX=clang++ ./configure ... && make
../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)
Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.
This patch was generated using:
$ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
sort -u >/tmp/changed_identifiers
$ for identifier in $(</tmp/changed_identifiers); do
sed -i "s%\<$identifier\>%q$identifier%g" \
$(git grep -I -l "\<$identifier\>")
done
I manually fixed line-wrap issues and misaligned rST tables.
Signed-off-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx>
..snip..
diff --git a/include/standard-headers/drivers/infiniband/hw/vmw_pvrdma/pvrdma_ring.h b/include/standard-headers/drivers/infiniband/hw/vmw_pvrdma/pvrdma_ring.h
index acd4c8346d..7b4062a1a1 100644
--- a/include/standard-headers/drivers/infiniband/hw/vmw_pvrdma/pvrdma_ring.h
+++ b/include/standard-headers/drivers/infiniband/hw/vmw_pvrdma/pvrdma_ring.h
@@ -68,7 +68,7 @@ static inline int pvrdma_idx_valid(uint32_t idx, uint32_t max_elems)
static inline int32_t pvrdma_idx(int *var, uint32_t max_elems)
{
- const unsigned int idx = atomic_read(var);
+ const unsigned int idx = qatomic_read(var);
if (pvrdma_idx_valid(idx, max_elems))
return idx & (max_elems - 1);
@@ -77,17 +77,17 @@ static inline int32_t pvrdma_idx(int *var, uint32_t max_elems)
static inline void pvrdma_idx_ring_inc(int *var, uint32_t max_elems)
{
- uint32_t idx = atomic_read(var) + 1; /* Increment. */
+ uint32_t idx = qatomic_read(var) + 1; /* Increment. */
idx &= (max_elems << 1) - 1; /* Modulo size, flip gen. */
- atomic_set(var, idx);
+ qatomic_set(var, idx);
}
static inline int32_t pvrdma_idx_ring_has_space(const struct pvrdma_ring *r,
uint32_t max_elems, uint32_t *out_tail)
{
- const uint32_t tail = atomic_read(&r->prod_tail);
- const uint32_t head = atomic_read(&r->cons_head);
+ const uint32_t tail = qatomic_read(&r->prod_tail);
+ const uint32_t head = qatomic_read(&r->cons_head);
if (pvrdma_idx_valid(tail, max_elems) &&
pvrdma_idx_valid(head, max_elems)) {
@@ -100,8 +100,8 @@ static inline int32_t pvrdma_idx_ring_has_space(const struct pvrdma_ring *r,
static inline int32_t pvrdma_idx_ring_has_data(const struct pvrdma_ring *r,
uint32_t max_elems, uint32_t *out_head)
{
- const uint32_t tail = atomic_read(&r->prod_tail);
- const uint32_t head = atomic_read(&r->cons_head);
+ const uint32_t tail = qatomic_read(&r->prod_tail);
+ const uint32_t head = qatomic_read(&r->cons_head);
if (pvrdma_idx_valid(tail, max_elems) &&
pvrdma_idx_valid(head, max_elems)) {
It looks like the changes in this file are going to get reverted the
next time someone does a linux header sync.
