linux

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History

Srivatsa S. Bhat 1e0b0c4c6b sparc, sysfs: Fix CPU hotplug callback registration

Subsystems that want to register CPU hotplug callbacks, as well as perform
initialization for the CPUs that are already online, often do it as shown
below:

	get_online_cpus();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	register_cpu_notifier(&foobar_cpu_notifier);

	put_online_cpus();

This is wrong, since it is prone to ABBA deadlocks involving the
cpu_add_remove_lock and the cpu_hotplug.lock (when running concurrently
with CPU hotplug operations).

Instead, the correct and race-free way of performing the callback
registration is:

	cpu_notifier_register_begin();

	for_each_online_cpu(cpu)
		init_cpu(cpu);

	/* Note the use of the double underscored version of the API */
	__register_cpu_notifier(&foobar_cpu_notifier);

	cpu_notifier_register_done();

Fix the sysfs code in sparc by using this latter form of callback
registration.

Cc: Ingo Molnar <mingo@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

2014-03-20 13:43:41 +01:00

boot

sparc: Fix piggyback with newer binutils.

2012-12-03 11:24:25 -08:00

configs

perf: Remove PERF_COUNTERS config option

2012-04-26 13:52:52 +02:00

crypto

sparc64: Set CRYPTO_TFM_REQ_MAY_SLEEP consistently in CAMELLIA code.

2012-12-19 15:44:31 -08:00

include

sparc: Hook up sched_setattr and sched_getattr syscalls.