diff options
| author | Chris Metcalf <cmetcalf@ezchip.com> | 2015-07-10 15:37:25 -0400 |
|---|---|---|
| committer | Frederic Weisbecker <fweisbec@gmail.com> | 2015-07-29 15:44:59 +0200 |
| commit | 03f6199a359e460714b6bd08c10b566760f150a6 (patch) | |
| tree | 71adc3d1afe58a51f80df84152b969d4a6d36df1 | |
| parent | 2019e8a3024bd8fcadd57891a88c838849216a5f (diff) | |
nohz: Prevent tilegx network driver interrupts
Normally the tilegx networking shim sends irqs to all the cores
to distribute the load of processing incoming-packet interrupts,
so that you can get to multiple Gb's of traffic inbound.
However, in nohz_full mode we don't want to interrupt the
nohz_full cores by default, so we limit the set of cores we use
to only the online housekeeping cores.
To make client code easier to read, we introduce a new nohz_full
accessor, housekeeping_cpumask(), which returns a pointer to the
housekeeping_mask if nohz_full is enabled, and otherwise returns
the cpu_possible_mask.
Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
| -rw-r--r-- | drivers/net/ethernet/tile/tilegx.c | 4 | ||||
| -rw-r--r-- | include/linux/tick.h | 9 |
2 files changed, 12 insertions, 1 deletions
diff --git a/drivers/net/ethernet/tile/tilegx.c b/drivers/net/ethernet/tile/tilegx.c index a3f7610002aa..0a15acc075b3 100644 --- a/drivers/net/ethernet/tile/tilegx.c +++ b/drivers/net/ethernet/tile/tilegx.c @@ -40,6 +40,7 @@ #include <linux/tcp.h> #include <linux/net_tstamp.h> #include <linux/ptp_clock_kernel.h> +#include <linux/tick.h> #include <asm/checksum.h> #include <asm/homecache.h> @@ -2273,7 +2274,8 @@ static int __init tile_net_init_module(void) tile_net_dev_init(name, mac); if (!network_cpus_init()) - network_cpus_map = *cpu_online_mask; + cpumask_and(&network_cpus_map, housekeeping_cpumask(), + cpu_online_mask); return 0; } diff --git a/include/linux/tick.h b/include/linux/tick.h index edbfc9a5293e..1ca93f2de6f5 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -163,6 +163,15 @@ static inline void tick_nohz_full_kick_all(void) { } static inline void __tick_nohz_task_switch(struct task_struct *tsk) { } #endif +static inline const struct cpumask *housekeeping_cpumask(void) +{ +#ifdef CONFIG_NO_HZ_FULL + if (tick_nohz_full_enabled()) + return housekeeping_mask; +#endif + return cpu_possible_mask; +} + static inline bool is_housekeeping_cpu(int cpu) { #ifdef CONFIG_NO_HZ_FULL |