mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2025-12-27 14:41:22 -05:00
The percpu interface is supposed to be preempt and irq safe. But: The uniprocessor implementation of percpu_counter_add() is not irq safe: if an interrupt happens during the +=, then the result is undefined. Therefore: switch from preempt_disable() to local_irq_save(). This prevents interrupts from interrupting the +=, and as a side effect prevents preemption. Link: https://lkml.kernel.org/r/20221216150441.200533-2-manfred@colorfullife.com Signed-off-by: Manfred Spraul <manfred@colorfullife.com> Cc: "Sun, Jiebin" <jiebin.sun@intel.com> Cc: <1vier1@web.de> Cc: Alexander Sverdlin <alexander.sverdlin@siemens.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>