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Commit282d8998e9("srcu: Prevent expedited GPs and blocking readers from consuming CPU") fixed a problem where a long-running expedited SRCU grace period could block kernel live patching. It did so by giving up on expediting once a given SRCU expedited grace period grew too old. Unfortunately, this added excessive delays to boots of virtual embedded systems specifying "-bios QEMU_EFI.fd" to qemu. This commit therefore makes the transition away from expediting less aggressive, increasing the per-grace-period phase number of non-sleeping polls of readers from one to three and increasing the required grace-period age from one jiffy (actually from zero to one jiffies) to two jiffies (actually from one to two jiffies). Fixes:282d8998e9("srcu: Prevent expedited GPs and blocking readers from consuming CPU") Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Reported-by: Zhangfei Gao <zhangfei.gao@linaro.org> Reported-by: chenxiang (M)" <chenxiang66@hisilicon.com> Cc: Shameerali Kolothum Thodi <shameerali.kolothum.thodi@huawei.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com> Link: https://lore.kernel.org/all/20615615-0013-5adc-584f-2b1d5c03ebfc@linaro.org/