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powerpc/64: Use array of paca pointers and allocate pacas individually

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Change the paca array into an array of pointers to pacas. Allocate
pacas individually.

This allows flexibility in where the PACAs are allocated. Future work
will allocate them node-local. Platforms that don't have address limits
on PACAs would be able to defer PACA allocations until later in boot
rather than allocate all possible ones up-front then freeing unused.

This is slightly more overhead (one additional indirection) for cross
CPU paca references, but those aren't too common.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Nicholas Piggin
2018-02-14 01:08:12 +10:00
committed by Michael Ellerman
parent 8e0b634b13
commit d2e60075a3
26 changed files with 141 additions and 105 deletions
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19
arch/powerpc/kernel/head_64.S
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@@ -392,19 +392,20 @@ generic_secondary_common_init:
* physical cpu id in r24, we need to search the pacas to find
* which logical id maps to our physical one.
*/
LOAD_REG_ADDR(r13, paca) /* Load paca pointer */
ld r13,0(r13) /* Get base vaddr of paca array */
#ifndef CONFIG_SMP
addi r13,r13,PACA_SIZE /* know r13 if used accidentally */
b kexec_wait /* wait for next kernel if !SMP */
#else
LOAD_REG_ADDR(r8, paca_ptrs) /* Load paca_ptrs pointe */
ld r8,0(r8) /* Get base vaddr of array */
LOAD_REG_ADDR(r7, nr_cpu_ids) /* Load nr_cpu_ids address */
lwz r7,0(r7) /* also the max paca allocated */
li r5,0 /* logical cpu id */
1: lhz r6,PACAHWCPUID(r13) /* Load HW procid from paca */
1:
sldi r9,r5,3 /* get paca_ptrs[] index from cpu id */
ldx r13,r9,r8 /* r13 = paca_ptrs[cpu id] */
lhz r6,PACAHWCPUID(r13) /* Load HW procid from paca */
cmpw r6,r24 /* Compare to our id */
beq 2f
addi r13,r13,PACA_SIZE /* Loop to next PACA on miss */
addi r5,r5,1
cmpw r5,r7 /* Check if more pacas exist */
blt 1b
@@ -756,10 +757,10 @@ _GLOBAL(pmac_secondary_start)
mtmsrd r3 /* RI on */
/* Set up a paca value for this processor. */
LOAD_REG_ADDR(r4,paca) /* Load paca pointer */
ld r4,0(r4) /* Get base vaddr of paca array */
mulli r13,r24,PACA_SIZE /* Calculate vaddr of right paca */
add r13,r13,r4 /* for this processor. */
LOAD_REG_ADDR(r4,paca_ptrs) /* Load paca pointer */
ld r4,0(r4) /* Get base vaddr of paca_ptrs array */
sldi r5,r24,3 /* get paca_ptrs[] index from cpu id */
ldx r13,r5,r4 /* r13 = paca_ptrs[cpu id] */
SET_PACA(r13) /* Save vaddr of paca in an SPRG*/
/* Mark interrupts soft and hard disabled (they might be enabled