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| author | Yewon Choi <woni9911@gmail.com> | 2024-03-15 18:28:38 +0900 |
|---|---|---|
| committer | Sasha Levin <sashal@kernel.org> | 2024-03-26 18:18:57 -0400 |
| commit | 917135195200e20e5244b9c3f2bb40f3d5e02510 (patch) | |
| tree | 34999a58b89f69ea61312f973905faf4f0818f57 | |
| parent | 3f94da807fe1668b9830f0eefbbf7e887b0a7bc6 (diff) | |
| download | linux-stable-917135195200e20e5244b9c3f2bb40f3d5e02510.tar.gz linux-stable-917135195200e20e5244b9c3f2bb40f3d5e02510.tar.bz2 linux-stable-917135195200e20e5244b9c3f2bb40f3d5e02510.zip | |
rds: introduce acquire/release ordering in acquire/release_in_xmit()
[ Upstream commit 1422f28826d2a0c11e5240b3e951c9e214d8656e ]
acquire/release_in_xmit() work as bit lock in rds_send_xmit(), so they
are expected to ensure acquire/release memory ordering semantics.
However, test_and_set_bit/clear_bit() don't imply such semantics, on
top of this, following smp_mb__after_atomic() does not guarantee release
ordering (memory barrier actually should be placed before clear_bit()).
Instead, we use clear_bit_unlock/test_and_set_bit_lock() here.
Fixes: 0f4b1c7e89e6 ("rds: fix rds_send_xmit() serialization")
Fixes: 1f9ecd7eacfd ("RDS: Pass rds_conn_path to rds_send_xmit()")
Signed-off-by: Yewon Choi <woni9911@gmail.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Link: https://lore.kernel.org/r/ZfQUxnNTO9AJmzwc@libra05
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | net/rds/send.c | 5 |
1 files changed, 2 insertions, 3 deletions
diff --git a/net/rds/send.c b/net/rds/send.c index 2899def23865..09a280110654 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -103,13 +103,12 @@ EXPORT_SYMBOL_GPL(rds_send_path_reset); static int acquire_in_xmit(struct rds_conn_path *cp) { - return test_and_set_bit(RDS_IN_XMIT, &cp->cp_flags) == 0; + return test_and_set_bit_lock(RDS_IN_XMIT, &cp->cp_flags) == 0; } static void release_in_xmit(struct rds_conn_path *cp) { - clear_bit(RDS_IN_XMIT, &cp->cp_flags); - smp_mb__after_atomic(); + clear_bit_unlock(RDS_IN_XMIT, &cp->cp_flags); /* * We don't use wait_on_bit()/wake_up_bit() because our waking is in a * hot path and finding waiters is very rare. We don't want to walk |