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authorDavid S. Miller <davem@davemloft.net>2020-07-25 17:49:04 -0700
committerDavid S. Miller <davem@davemloft.net>2020-07-25 17:49:04 -0700
commita57066b1a01977a646145f4ce8dfb4538b08368a (patch)
tree57c2b4fa2fc48e687a1820b9bf4ef4f4363be0f9 /arch/riscv/include/asm/barrier.h
parentdfecd3e00cd32b2a6d1cfdb30b513dd42575ada3 (diff)
parent04300d66f0a06d572d9f2ad6768c38cabde22179 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The UDP reuseport conflict was a little bit tricky. The net-next code, via bpf-next, extracted the reuseport handling into a helper so that the BPF sk lookup code could invoke it. At the same time, the logic for reuseport handling of unconnected sockets changed via commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace which changed the logic to carry on the reuseport result into the rest of the lookup loop if we do not return immediately. This requires moving the reuseport_has_conns() logic into the callers. While we are here, get rid of inline directives as they do not belong in foo.c files. The other changes were cases of more straightforward overlapping modifications. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/riscv/include/asm/barrier.h')
-rw-r--r--arch/riscv/include/asm/barrier.h10
1 files changed, 9 insertions, 1 deletions
diff --git a/arch/riscv/include/asm/barrier.h b/arch/riscv/include/asm/barrier.h
index 3f1737f301cc..d0e24aaa2aa0 100644
--- a/arch/riscv/include/asm/barrier.h
+++ b/arch/riscv/include/asm/barrier.h
@@ -58,8 +58,16 @@ do { \
* The AQ/RL pair provides a RCpc critical section, but there's not really any
* way we can take advantage of that here because the ordering is only enforced
* on that one lock. Thus, we're just doing a full fence.
+ *
+ * Since we allow writeX to be called from preemptive regions we need at least
+ * an "o" in the predecessor set to ensure device writes are visible before the
+ * task is marked as available for scheduling on a new hart. While I don't see
+ * any concrete reason we need a full IO fence, it seems safer to just upgrade
+ * this in order to avoid any IO crossing a scheduling boundary. In both
+ * instances the scheduler pairs this with an mb(), so nothing is necessary on
+ * the new hart.
*/
-#define smp_mb__after_spinlock() RISCV_FENCE(rw,rw)
+#define smp_mb__after_spinlock() RISCV_FENCE(iorw,iorw)
#include <asm-generic/barrier.h>