The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=db6b56441e3a142e7fe58a5a85d9071e772a943e
commit db6b56441e3a142e7fe58a5a85d9071e772a943e Author: Mark Johnston <[email protected]> AuthorDate: 2021-02-08 14:19:27 +0000 Commit: Mark Johnston <[email protected]> CommitDate: 2021-02-08 14:19:27 +0000 ktls: Avoid wakeups and locking for synchronous callbacks When performing encryption in software, the KTLS crypto callback always locks the session to deliver a wakeup. But, if we're handling the operation synchronously this is wasted effort and can result in sleepqueue lock contention on large systems. Use CRYPTO_SESS_SYNC() to determine whether the operation will be completed asynchronously or not, and select a callback appropriately. Avoid locking the session to check for completion if the session handles requests synchronously. Reviewed by: jhb Sponsored by: Ampere Computing Submitted by: Klara, Inc. MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D28195 --- sys/opencrypto/ktls_ocf.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/sys/opencrypto/ktls_ocf.c b/sys/opencrypto/ktls_ocf.c index 7f9ece99ccb1..28c55257b047 100644 --- a/sys/opencrypto/ktls_ocf.c +++ b/sys/opencrypto/ktls_ocf.c @@ -108,7 +108,13 @@ SYSCTL_COUNTER_U64(_kern_ipc_tls_stats_ocf, OID_AUTO, retries, CTLFLAG_RD, "Number of OCF encryption operation retries"); static int -ktls_ocf_callback(struct cryptop *crp) +ktls_ocf_callback_sync(struct cryptop *crp __unused) +{ + return (0); +} + +static int +ktls_ocf_callback_async(struct cryptop *crp) { struct ocf_operation *oo; @@ -125,21 +131,26 @@ ktls_ocf_dispatch(struct ocf_session *os, struct cryptop *crp) { struct ocf_operation oo; int error; + bool async; oo.os = os; oo.done = false; crp->crp_opaque = &oo; - crp->crp_callback = ktls_ocf_callback; for (;;) { + async = !CRYPTO_SESS_SYNC(crp->crp_session); + crp->crp_callback = async ? ktls_ocf_callback_async : + ktls_ocf_callback_sync; + error = crypto_dispatch(crp); if (error) break; - - mtx_lock(&os->lock); - while (!oo.done) - mtx_sleep(&oo, &os->lock, 0, "ocfktls", 0); - mtx_unlock(&os->lock); + if (async) { + mtx_lock(&os->lock); + while (!oo.done) + mtx_sleep(&oo, &os->lock, 0, "ocfktls", 0); + mtx_unlock(&os->lock); + } if (crp->crp_etype != EAGAIN) { error = crp->crp_etype; _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/dev-commits-src-main To unsubscribe, send any mail to "[email protected]"
