sparc: Touch NMI watchdog when walking cpus and calling printk
authorDavid Ahern <david.ahern@oracle.com>
Thu, 19 Mar 2015 20:06:53 +0000 (16:06 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 26 Mar 2015 14:00:55 +0000 (15:00 +0100)
[ Upstream commit 31aaa98c248da766ece922bbbe8cc78cfd0bc920 ]

With the increase in number of CPUs calls to functions that dump
output to console (e.g., arch_trigger_all_cpu_backtrace) can take
a long time to complete. If IRQs are disabled eventually the NMI
watchdog kicks in and creates more havoc. Avoid by telling the NMI
watchdog everything is ok.

Signed-off-by: David Ahern <david.ahern@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/sparc/kernel/process_64.c

index b9cc9763faf4aa9ef7570867d788c191f9494ec7..036e43cef6fb07cee2a4c2992a635af776be4327 100644 (file)
@@ -280,6 +280,8 @@ void arch_trigger_all_cpu_backtrace(void)
                        printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
                               gp->tpc, gp->o7, gp->i7, gp->rpc);
                }
+
+               touch_nmi_watchdog();
        }
 
        memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));
@@ -352,6 +354,8 @@ static void pmu_snapshot_all_cpus(void)
                       (cpu == this_cpu ? '*' : ' '), cpu,
                       pp->pcr[0], pp->pcr[1], pp->pcr[2], pp->pcr[3],
                       pp->pic[0], pp->pic[1], pp->pic[2], pp->pic[3]);
+
+               touch_nmi_watchdog();
        }
 
        memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot));