From 1f52a9380ff19b6fc00c1614488d5940773ba3ab Mon Sep 17 00:00:00 2001 From: Dust Li Date: Fri, 31 Dec 2021 14:08:53 +0800 Subject: [PATCH] net/smc: add comments for smc_link_{usable|sendable} Add comments for both smc_link_sendable() and smc_link_usable() to help better distinguish and use them. No function changes. Signed-off-by: Dust Li Signed-off-by: David S. Miller --- net/smc/smc_core.h | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index 1e4e90faf657..e778f97da700 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -409,7 +409,13 @@ static inline struct smc_connection *smc_lgr_find_conn( return res; } -/* returns true if the specified link is usable */ +/* + * Returns true if the specified link is usable. + * + * usable means the link is ready to receive RDMA messages, map memory + * on the link, etc. This doesn't ensure we are able to send RDMA messages + * on this link, if sending RDMA messages is needed, use smc_link_sendable() + */ static inline bool smc_link_usable(struct smc_link *lnk) { if (lnk->state == SMC_LNK_UNUSED || lnk->state == SMC_LNK_INACTIVE) @@ -417,6 +423,15 @@ static inline bool smc_link_usable(struct smc_link *lnk) return true; } +/* + * Returns true if the specified link is ready to receive AND send RDMA + * messages. + * + * For the client side in first contact, the underlying QP may still in + * RESET or RTR when the link state is ACTIVATING, checks in smc_link_usable() + * is not strong enough. For those places that need to send any CDC or LLC + * messages, use smc_link_sendable(), otherwise, use smc_link_usable() instead + */ static inline bool smc_link_sendable(struct smc_link *lnk) { return smc_link_usable(lnk) &&