[PATCH v6 25/46] staging: octeon: Use get/put_online_cpus_atomic() to prevent CPU offline
From: Srivatsa S. Bhat <hidden>
Date: 2013-02-18 12:43:52
Also in:
linux-arch, linux-arm-kernel, linux-pm, lkml, netdev
Subsystem:
staging subsystem, the rest · Maintainers:
Greg Kroah-Hartman, Linus Torvalds
Once stop_machine() is gone from the CPU offline path, we won't be able to depend on preempt_disable() or local_irq_disable() 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: David Daney <redacted> Signed-off-by: Srivatsa S. Bhat <redacted> --- drivers/staging/octeon/ethernet-rx.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/staging/octeon/ethernet-rx.c b/drivers/staging/octeon/ethernet-rx.c
index 34afc16..8588b4d 100644
--- a/drivers/staging/octeon/ethernet-rx.c
+++ b/drivers/staging/octeon/ethernet-rx.c@@ -36,6 +36,7 @@ #include <linux/prefetch.h> #include <linux/ratelimit.h> #include <linux/smp.h> +#include <linux/cpu.h> #include <linux/interrupt.h> #include <net/dst.h> #ifdef CONFIG_XFRM
@@ -97,6 +98,7 @@ static void cvm_oct_enable_one_cpu(void) return; /* ... if a CPU is available, Turn on NAPI polling for that CPU. */ + get_online_cpus_atomic(); for_each_online_cpu(cpu) { if (!cpu_test_and_set(cpu, core_state.cpu_state)) { v = smp_call_function_single(cpu, cvm_oct_enable_napi,
@@ -106,6 +108,7 @@ static void cvm_oct_enable_one_cpu(void) break; } } + put_online_cpus_atomic(); } static void cvm_oct_no_more_work(void)