Author: hselasky Date: Mon Sep 21 18:21:59 2020 New Revision: 365962 URL: https://svnweb.freebsd.org/changeset/base/365962
Log: MFC r365237: Micro optimise _callout_stop_safe() by removing dead code. The CS_DRAIN flag cannot be set at the same time like the async-drain function pointer is set. These are orthogonal features. Assert this at the beginning of the function. Before: if (flags & CS_DRAIN) { /* FALLTHROUGH */ } else if (xxx) { return yyy; } if (drain) { zzz = drain; } After: if (flags & CS_DRAIN) { /* FALLTHROUGH */ } else if (xxx) { return yyy; } else { if (drain) { zzz = drain; } } Reviewed by: markj@ Tested by: callout_test Differential Revision: https://reviews.freebsd.org/D26285 Sponsored by: Mellanox Technologies // NVIDIA Networking Modified: stable/12/sys/kern/kern_timeout.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/kern/kern_timeout.c ============================================================================== --- stable/12/sys/kern/kern_timeout.c Mon Sep 21 18:19:48 2020 (r365961) +++ stable/12/sys/kern/kern_timeout.c Mon Sep 21 18:21:59 2020 (r365962) @@ -1188,6 +1188,9 @@ _callout_stop_safe(struct callout *c, int flags, callo WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, c->c_lock, "calling %s", __func__); + KASSERT((flags & CS_DRAIN) == 0 || drain == NULL, + ("Cannot set drain callback and CS_DRAIN flag at the same time")); + /* * Some old subsystems don't hold Giant while running a callout_stop(), * so just discard this check for the moment. @@ -1383,11 +1386,12 @@ again: } CC_UNLOCK(cc); return ((flags & CS_EXECUTING) != 0); - } - CTR3(KTR_CALLOUT, "failed to stop %p func %p arg %p", - c, c->c_func, c->c_arg); - if (drain) { - cc_exec_drain(cc, direct) = drain; + } else { + CTR3(KTR_CALLOUT, "failed to stop %p func %p arg %p", + c, c->c_func, c->c_arg); + if (drain) { + cc_exec_drain(cc, direct) = drain; + } } KASSERT(!sq_locked, ("sleepqueue chain still locked")); cancelled = ((flags & CS_EXECUTING) != 0); _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"