diff options
Diffstat (limited to 'usr/src')
| -rw-r--r-- | usr/src/uts/common/io/mac/mac_sched.c | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/usr/src/uts/common/io/mac/mac_sched.c b/usr/src/uts/common/io/mac/mac_sched.c index 59bb5c27fc..76188b4223 100644 --- a/usr/src/uts/common/io/mac/mac_sched.c +++ b/usr/src/uts/common/io/mac/mac_sched.c @@ -21,6 +21,8 @@ /* * Copyright 2010 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. + */ +/* * Copyright 2011 Joyent, Inc. All rights reserved. */ @@ -30,6 +32,8 @@ #include <sys/strsubr.h> #include <sys/strsun.h> #include <sys/vlan.h> +#include <sys/stack.h> +#include <sys/archsystm.h> #include <inet/ipsec_impl.h> #include <inet/ip_impl.h> #include <inet/sadb.h> @@ -416,6 +420,27 @@ int mac_srs_worker_wakeup_ticks = 0; } /* + * MAC_RX_SRS_TOODEEP + * + * Macro called as part of receive-side processing to determine if handling + * can occur in situ (in the interrupt thread) or if it should be left to a + * worker thread. Note that the constant used to make this determination is + * not entirely made-up, and is a result of some emprical validation. That + * said, the constant is left as a static variable to allow it to be + * dynamically tuned in the field if and as needed. + */ +static uintptr_t mac_rx_srs_stack_needed = 8192; +static int mac_rx_srs_stack_toodeep; + +#ifndef STACK_GROWTH_DOWN +#error Downward stack growth assumed. +#endif + +#define MAC_RX_SRS_TOODEEP() (STACK_BIAS + (uintptr_t)getfp() - \ + (uintptr_t)curthread->t_stkbase < mac_rx_srs_stack_needed && \ + ++mac_rx_srs_stack_toodeep) + +/* * Drop the rx packet and advance to the next one in the chain. */ static void @@ -2506,11 +2531,12 @@ mac_rx_srs_process(void *arg, mac_resource_handle_t srs, mblk_t *mp_chain, if (!(mac_srs->srs_state & SRS_PROC)) { /* - * If we are coming via loopback or if we are not - * optimizing for latency, we should signal the - * worker thread. + * If we are coming via loopback or if we are not optimizing + * for latency or if our stack is running deep, we should + * signal the worker thread. */ - if (loopback || !(mac_srs->srs_state & SRS_LATENCY_OPT)) { + if (loopback || !(mac_srs->srs_state & SRS_LATENCY_OPT) || + MAC_RX_SRS_TOODEEP()) { /* * For loopback, We need to let the worker take * over as we don't want to continue in the same |