On Tue, Oct 17, 2023 at 6:39 PM Hari Bathini <hbathini@xxxxxxxxxxxxx> wrote: > > > > On 17/10/23 7:58 am, Pingfan Liu wrote: > > *** Idea *** > > For kexec -p, the boot cpu can be not the cpu0, this causes the problem > > of allocating memory for paca_ptrs[]. However, in theory, there is no > > requirement to assign cpu's logical id as its present sequence in the > > device tree. But there is something like cpu_first_thread_sibling(), > > which makes assumption on the mapping inside a core. Hence partially > > loosening the mapping, i.e. unbind the mapping of core while keep the > > mapping inside a core. > > > > *** Implement *** > > At this early stage, there are plenty of memory to utilize. Hence, this > > patch allocates interim memory to link the cpu info on a list, then > > reorder cpus by changing the list head. As a result, there is a rotate > > shift between the sequence number in dt and the cpu logical number. > > > > *** Result *** > > After this patch, a boot-cpu's logical id will always be mapped into the > > range [0,threads_per_core). > > > > Besides this, at this phase, all threads in the boot core are forced to > > be onlined. This restriction will be lifted in a later patch with > > extra effort. > > > > Signed-off-by: Pingfan Liu <piliu@xxxxxxxxxx> > > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > > Cc: Nicholas Piggin <npiggin@xxxxxxxxx> > > Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > > Cc: Mahesh Salgaonkar <mahesh@xxxxxxxxxxxxx> > > Cc: Wen Xiong <wenxiong@xxxxxxxxxx> > > Cc: Baoquan He <bhe@xxxxxxxxxx> > > Cc: Ming Lei <ming.lei@xxxxxxxxxx> > > Cc: Sourabh Jain <sourabhjain@xxxxxxxxxxxxx> > > Cc: Hari Bathini <hbathini@xxxxxxxxxxxxx> > > Cc: kexec@xxxxxxxxxxxxxxxxxxx > > To: linuxppc-dev@xxxxxxxxxxxxxxxx > > Thanks for working on this, Pingfan. > Looks good to me. > > Acked-by: Hari Bathini <hbathini@xxxxxxxxxxxxx> > Thank you for kindly reviewing. I hope that after all these years, we have accomplished the objective. Best Regards, Pingfan _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
