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authorJakub Kicinski <kuba@kernel.org>2024-03-28 17:24:10 -0700
committerJakub Kicinski <kuba@kernel.org>2024-03-28 17:25:57 -0700
commit5e47fbe5cefe5d25d1fa4481c1b9fbe602b4a69f (patch)
treeb86edc39098cca1d0e53e46dceec6ca856183642 /kernel/sched/membarrier.c
parent2a702c2e57908e7bb5c814afeac577a14815c2f2 (diff)
parent50108c352db70405b3d71d8099d0b3adc3b3352c (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts, or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'kernel/sched/membarrier.c')
-rw-r--r--kernel/sched/membarrier.c13
1 files changed, 9 insertions, 4 deletions
diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c
index 4e715b9b278e..809194cd779f 100644
--- a/kernel/sched/membarrier.c
+++ b/kernel/sched/membarrier.c
@@ -254,7 +254,7 @@ static int membarrier_global_expedited(void)
return 0;
/*
- * Matches memory barriers around rq->curr modification in
+ * Matches memory barriers after rq->curr modification in
* scheduler.
*/
smp_mb(); /* system call entry is not a mb. */
@@ -304,7 +304,7 @@ static int membarrier_global_expedited(void)
/*
* Memory barrier on the caller thread _after_ we finished
- * waiting for the last IPI. Matches memory barriers around
+ * waiting for the last IPI. Matches memory barriers before
* rq->curr modification in scheduler.
*/
smp_mb(); /* exit from system call is not a mb */
@@ -324,6 +324,7 @@ static int membarrier_private_expedited(int flags, int cpu_id)
MEMBARRIER_STATE_PRIVATE_EXPEDITED_SYNC_CORE_READY))
return -EPERM;
ipi_func = ipi_sync_core;
+ prepare_sync_core_cmd(mm);
} else if (flags == MEMBARRIER_FLAG_RSEQ) {
if (!IS_ENABLED(CONFIG_RSEQ))
return -EINVAL;
@@ -343,8 +344,12 @@ static int membarrier_private_expedited(int flags, int cpu_id)
return 0;
/*
- * Matches memory barriers around rq->curr modification in
+ * Matches memory barriers after rq->curr modification in
* scheduler.
+ *
+ * On RISC-V, this barrier pairing is also needed for the
+ * SYNC_CORE command when switching between processes, cf.
+ * the inline comments in membarrier_arch_switch_mm().
*/
smp_mb(); /* system call entry is not a mb. */
@@ -420,7 +425,7 @@ out:
/*
* Memory barrier on the caller thread _after_ we finished
- * waiting for the last IPI. Matches memory barriers around
+ * waiting for the last IPI. Matches memory barriers before
* rq->curr modification in scheduler.
*/
smp_mb(); /* exit from system call is not a mb */