@@ -43,6 +43,7 @@
#include <linux/slab.h>
#include <linux/smpboot.h>
+#include <linux/cpu.h>
#include "ehca_classes.h"
#include "ehca_irq.h"
@@ -703,6 +704,7 @@ static void queue_comp_task(struct ehca_cq *__cq)
int cq_jobs;
unsigned long flags;
+ get_online_cpus_atomic();
cpu_id = find_next_online_cpu(pool);
BUG_ON(!cpu_online(cpu_id));
@@ -720,6 +722,7 @@ static void queue_comp_task(struct ehca_cq *__cq)
BUG_ON(!cct || !thread);
}
__queue_comp_task(__cq, cct, thread);
+ put_online_cpus_atomic();
}
static void run_comp_task(struct ehca_cpu_comp_task *cct)
@@ -759,6 +762,7 @@ static void comp_task_park(unsigned int cpu)
list_splice_init(&cct->cq_list, &list);
spin_unlock_irq(&cct->task_lock);
+ get_online_cpus_atomic();
cpu = find_next_online_cpu(pool);
target = per_cpu_ptr(pool->cpu_comp_tasks, cpu);
thread = *per_cpu_ptr(pool->cpu_comp_threads, cpu);
@@ -768,6 +772,7 @@ static void comp_task_park(unsigned int cpu)
__queue_comp_task(cq, target, thread);
}
spin_unlock_irq(&target->task_lock);
+ put_online_cpus_atomic();
}
static void comp_task_stop(unsigned int cpu, bool online)
Once stop_machine() is gone from the CPU offline path, we won't be able to depend on disabling preemption to prevent CPUs from going offline from under us. Use the get/put_online_cpus_atomic() APIs to prevent CPUs from going offline, while invoking from atomic context. Cc: Hoang-Nam Nguyen <hnguyen@de.ibm.com> Cc: Christoph Raisch <raisch@de.ibm.com> Cc: Roland Dreier <roland@kernel.org> Cc: Sean Hefty <sean.hefty@intel.com> Cc: Hal Rosenstock <hal.rosenstock@gmail.com> Cc: linux-rdma@vger.kernel.org Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> --- drivers/infiniband/hw/ehca/ehca_irq.c | 5 +++++ 1 file changed, 5 insertions(+)