From: Milton Miller Date: Wed, 11 Apr 2007 08:32:17 +0000 (+1000) Subject: [POWERPC] kexec: Send slaves to new kernel earlier X-Git-Tag: v2.6.23-rc1~767^2^2~163 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ee46a90b599952bb1a9dc67f894710017e7cc409;p=linux-2.6 [POWERPC] kexec: Send slaves to new kernel earlier With this, when kexec-ing, we copy the code and start the slaves on their journey to the next kernel's spin loop as soon as we copy the kexec image into place. The kernel doesn't know exactly which slaves are spinning in kexec_wait. This allows us to pass more than max-cpus to the next kernel. But it also means that we might leave some behind. Moving the code here means they have the time it takes us to clear the hash table to wake up and move on. Moving the code any earlier would reuqire walking the image description to search for the code, which could span multiple pages. Signed-off-by: Milton Miller Signed-off-by: Paul Mackerras --- diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index 519861da04..bbb3ba54c5 100644 --- a/arch/powerpc/kernel/misc_64.S +++ b/arch/powerpc/kernel/misc_64.S @@ -646,6 +646,19 @@ _GLOBAL(kexec_sequence) /* turn off mmu */ bl real_mode + /* copy 0x100 bytes starting at start to 0 */ + li r3,0 + mr r4,r30 /* start, aka phys mem offset */ + li r5,0x100 + li r6,0 + bl .copy_and_flush /* (dest, src, copy limit, start offset) */ +1: /* assume normal blr return */ + + /* release other cpus to the new kernel secondary start at 0x60 */ + mflr r5 + li r6,1 + stw r6,kexec_flag-1b(5) + /* clear out hardware hash page table and tlb */ ld r5,0(r27) /* deref function descriptor */ mtctr r5 @@ -676,19 +689,6 @@ _GLOBAL(kexec_sequence) * are the boot cpu ????? * other device tree differences (prop sizes, va vs pa, etc)... */ - - /* copy 0x100 bytes starting at start to 0 */ - li r3,0 - mr r4,r30 - li r5,0x100 - li r6,0 - bl .copy_and_flush /* (dest, src, copy limit, start offset) */ -1: /* assume normal blr return */ - - /* release other cpus to the new kernel secondary start at 0x60 */ - mflr r5 - li r6,1 - stw r6,kexec_flag-1b(5) mr r3,r25 # my phys cpu mr r4,r30 # start, aka phys mem offset mtlr 4