x86/mm/tlb: Open-code on_each_cpu_cond_mask() for tlb_is_not_lazy()
mainline inclusion from mainline-v5.13-rc1 commit 6035152d category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I3ZV2C CVE: NA ------------------------------------------------- Open-code on_each_cpu_cond_mask() in native_flush_tlb_others() to optimize the code. Open-coding eliminates the need for the indirect branch that is used to call is_lazy(), and in CPUs that are vulnerable to Spectre v2, it eliminates the retpoline. In addition, it allows to use a preallocated cpumask to compute the CPUs that should be. This would later allow us not to adapt on_each_cpu_cond_mask() to support local and remote functions. Note that calling tlb_is_not_lazy() for every CPU that needs to be flushed, as done in native_flush_tlb_multi() might look ugly, but it is equivalent to what is currently done in on_each_cpu_cond_mask(). Actually, native_flush_tlb_multi() does it more efficiently since it avoids using an indirect branch for the matter. Signed-off-by: NNadav Amit <namit@vmware.com> Signed-off-by: NIngo Molnar <mingo@kernel.org> Reviewed-by: NDave Hansen <dave.hansen@linux.intel.com> Link: https://lore.kernel.org/r/20210220231712.2475218-4-namit@vmware.comSigned-off-by: NTong Tiangen <tongtiangen@huawei.com> Reviewed-by: NChen Wandun <chenwandun@huawei.com> Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
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