From mboxrd@z Thu Jan 1 00:00:00 1970 From: srivatsa.bhat@linux.vnet.ibm.com (Srivatsa S. Bhat) Date: Tue, 22 Jan 2013 13:09:31 +0530 Subject: [PATCH v5 24/45] staging: octeon: Use get/put_online_cpus_atomic() to prevent CPU offline In-Reply-To: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> References: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> Message-ID: <20130122073928.13822.79334.stgit@srivatsabhat.in.ibm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 Cc: David Daney Signed-off-by: Srivatsa S. Bhat --- 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 #include #include +#include #include #include #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)