From 50a10043fd4c12c008bc607d30a72b59d2f2dee9 Mon Sep 17 00:00:00 2001 From: James Simmons Date: Wed, 23 Dec 2015 16:24:40 -0500 Subject: [PATCH] staging: lustre: kg_sem semaphore handling is incorrectly During the removal of the cfs wrappers the kg_sem semaphore was handled incorrectly. We need to take a write lock when writing data to the kkuc_groups. The libcfs_kkuc_group_foreach needs to only take a read lock. This makes use match the OpenSFS development branch. Signed-off-by: James Simmons Signed-off-by: Greg Kroah-Hartman --- drivers/staging/lustre/lustre/libcfs/kernel_user_comm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/staging/lustre/lustre/libcfs/kernel_user_comm.c b/drivers/staging/lustre/lustre/libcfs/kernel_user_comm.c index d8230aec9a2b..1a052ac8524d 100644 --- a/drivers/staging/lustre/lustre/libcfs/kernel_user_comm.c +++ b/drivers/staging/lustre/lustre/libcfs/kernel_user_comm.c @@ -186,7 +186,7 @@ int libcfs_kkuc_group_put(int group, void *payload) int rc = 0; int one_success = 0; - down_read(&kg_sem); + down_write(&kg_sem); list_for_each_entry(reg, &kkuc_groups[group], kr_chain) { if (reg->kr_fp != NULL) { rc = libcfs_kkuc_msg_put(reg->kr_fp, payload); @@ -198,7 +198,7 @@ int libcfs_kkuc_group_put(int group, void *payload) } } } - up_read(&kg_sem); + up_write(&kg_sem); /* don't return an error if the message has been delivered * at least to one agent */ @@ -230,12 +230,12 @@ int libcfs_kkuc_group_foreach(int group, libcfs_kkuc_cb_t cb_func, if (kkuc_groups[group].next == NULL) return 0; - down_write(&kg_sem); + down_read(&kg_sem); list_for_each_entry(reg, &kkuc_groups[group], kr_chain) { if (reg->kr_fp != NULL) rc = cb_func(reg->kr_data, cb_arg); } - up_write(&kg_sem); + up_read(&kg_sem); return rc; } -- 2.34.1