Messages in this thread |  | | Date | Wed, 3 Oct 2018 16:09:11 +1000 | From | Nicholas Piggin <> | Subject | Re: [RFC PATCH v3 5/7] powerpc: 'current_set' is now a table of task_struct pointers |
| |
On Wed, 3 Oct 2018 08:00:43 +0200 Christophe LEROY <christophe.leroy@c-s.fr> wrote:
> Le 03/10/2018 à 07:41, Nicholas Piggin a écrit : > > On Mon, 1 Oct 2018 12:30:27 +0000 (UTC) > > Christophe Leroy <christophe.leroy@c-s.fr> wrote: > > > >> The table of pointers 'current_set' has been used for retrieving > >> the stack and current. They used to be thread_info pointers as > >> they were pointing to the stack and current was taken from the > >> 'task' field of the thread_info. > >> > >> Now, the pointers of 'current_set' table are now both pointers > >> to task_struct and pointers to thread_info. > >> > >> As they are used to get current, and the stack pointer is > >> retrieved from current's stack field, this patch changes > >> their type to task_struct, and renames secondary_ti to > >> secondary_current. > > > > I'm not sure if current_set is actually needed is it? Because > > 64-bit already initializes paca->ksave / PACAKSAVE. That might > > be a cleanup to do after your series. > > head_64.S contains: > > __secondary_start: > /* Set thread priority to MEDIUM */ > HMT_MEDIUM > > /* Initialize the kernel stack */ > LOAD_REG_ADDR(r3, current_set) > sldi r28,r24,3 /* get current_set[cpu#] */ > ldx r14,r3,r28 > addi r14,r14,THREAD_SIZE-STACK_FRAME_OVERHEAD > std r14,PACAKSAVE(r13)
Right, I don't *think* that's needed because boot CPU should already have set PACAKSAVE before starting secondaries here. ld r14,PACAKSAVE should have the same result I think.
But never mind that for your series, just something I saw that could be cleaned up.
Thanks, Nick
|  |