Currently all iSeries secondary CPU's spin directly on the cpu_start in thier
paca. Make them spin on the global __secondary_hold_spinloop, until after the
pacas have been initialised.
As sfr points out this works because __secondary_hold_spinloop is being set
already, but iSeries isn't looking at it :)
Signed-off-by: Tony Breeds <[EMAIL PROTECTED]>
Acked-by: Stephen Rothwell <[EMAIL PROTECTED]>
---
Changes since v1:
- Updated commit message.
arch/powerpc/kernel/paca.c | 64 ++--------------------------
arch/powerpc/platforms/iseries/exception.S | 27 +++++++++++-
include/asm-powerpc/paca.h | 17 -------
3 files changed, 30 insertions(+), 78 deletions(-)
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
index 4c7db2e..c9bf17e 100644
--- a/arch/powerpc/kernel/paca.c
+++ b/arch/powerpc/kernel/paca.c
@@ -7,26 +7,11 @@
* 2 of the License, or (at your option) any later version.
*/
-#include <linux/types.h>
#include <linux/threads.h>
#include <linux/module.h>
-#include <asm/processor.h>
-#include <asm/ptrace.h>
-#include <asm/page.h>
#include <asm/lppaca.h>
#include <asm/paca.h>
-#include <asm/mmu.h>
-
-/*
- * In order to handle "strange" values of NR_CPUS, Make sure we use
- * max(NR_CPUS, NR_STATIC_PACAS) for array sizes below
- */
-#if NR_CPUS > NR_STATIC_PACAS
-#define MAX_CPUS NR_CPUS
-#else
-#define MAX_CPUS NR_STATIC_PACAS
-#endif
/* This symbol is provided by the linker - let it fill in the paca
* field correctly */
@@ -42,7 +27,7 @@ extern unsigned long __toc_start;
* will suffice to ensure that it doesn't cross a page boundary.
*/
struct lppaca lppaca[] = {
- [0 ... (MAX_CPUS-1)] = {
+ [0 ... (NR_CPUS-1)] = {
.desc = 0xd397d781, /* "LpPa" */
.size = sizeof(struct lppaca),
.dyn_proc_status = 2,
@@ -59,7 +44,7 @@ struct lppaca lppaca[] = {
* initially, hence will all be invaild until we actually write them.
*/
struct slb_shadow slb_shadow[] __cacheline_aligned = {
- [0 ... (MAX_CPUS-1)] = {
+ [0 ... (NR_CPUS-1)] = {
.persistent = SLB_NUM_BOLTED,
.buffer_length = sizeof(struct slb_shadow),
},
@@ -74,50 +59,9 @@ struct slb_shadow slb_shadow[] __cacheline_aligned = {
* processors. The processor VPD array needs one entry per physical
* processor (not thread).
*/
-#define PACA_INIT(number) \
-{ \
- .lppaca_ptr = &lppaca[number], \
- .lock_token = 0x8000, \
- .paca_index = (number), /* Paca Index */ \
- .kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL, \
- .hw_cpu_id = 0xffff, \
- .slb_shadow_ptr = &slb_shadow[number], \
- .__current = &init_task, \
-}
-
-struct paca_struct paca[MAX_CPUS] = {
- PACA_INIT(0),
-#if NR_CPUS > 1
- PACA_INIT( 1), PACA_INIT( 2), PACA_INIT( 3),
-#if NR_CPUS > 4
- PACA_INIT( 4), PACA_INIT( 5), PACA_INIT( 6), PACA_INIT( 7),
-#if NR_CPUS > 8
- PACA_INIT( 8), PACA_INIT( 9), PACA_INIT( 10), PACA_INIT( 11),
- PACA_INIT( 12), PACA_INIT( 13), PACA_INIT( 14), PACA_INIT( 15),
- PACA_INIT( 16), PACA_INIT( 17), PACA_INIT( 18), PACA_INIT( 19),
- PACA_INIT( 20), PACA_INIT( 21), PACA_INIT( 22), PACA_INIT( 23),
- PACA_INIT( 24), PACA_INIT( 25), PACA_INIT( 26), PACA_INIT( 27),
- PACA_INIT( 28), PACA_INIT( 29), PACA_INIT( 30), PACA_INIT( 31),
-#if NR_CPUS > 32
- PACA_INIT( 32), PACA_INIT( 33), PACA_INIT( 34), PACA_INIT( 35),
- PACA_INIT( 36), PACA_INIT( 37), PACA_INIT( 38), PACA_INIT( 39),
- PACA_INIT( 40), PACA_INIT( 41), PACA_INIT( 42), PACA_INIT( 43),
- PACA_INIT( 44), PACA_INIT( 45), PACA_INIT( 46), PACA_INIT( 47),
- PACA_INIT( 48), PACA_INIT( 49), PACA_INIT( 50), PACA_INIT( 51),
- PACA_INIT( 52), PACA_INIT( 53), PACA_INIT( 54), PACA_INIT( 55),
- PACA_INIT( 56), PACA_INIT( 57), PACA_INIT( 58), PACA_INIT( 59),
- PACA_INIT( 60), PACA_INIT( 61), PACA_INIT( 62), PACA_INIT( 63),
-#endif
-#endif
-#endif
-#endif
-};
+struct paca_struct paca[NR_CPUS];
EXPORT_SYMBOL(paca);
-/*
- * The first few (NR_STATIC_PACAS) paca entires are initiialised
- * statically. populate the rest.
- */
void __init initialise_pacas(void)
{
int cpu;
@@ -128,7 +72,7 @@ void __init initialise_pacas(void)
unsigned long kernel_toc = (unsigned long)(&__toc_start) + 0x8000UL;
/* Can't use for_each_*_cpu, as they aren't functional yet */
- for (cpu = NR_STATIC_PACAS; cpu < NR_CPUS; cpu++) {
+ for (cpu = 0; cpu < NR_CPUS; cpu++) {
struct paca_struct *new_paca = &paca[cpu];
new_paca->lppaca_ptr = &lppaca[cpu];
diff --git a/arch/powerpc/platforms/iseries/exception.S
b/arch/powerpc/platforms/iseries/exception.S
index c775cd4..8ff330d 100644
--- a/arch/powerpc/platforms/iseries/exception.S
+++ b/arch/powerpc/platforms/iseries/exception.S
@@ -59,8 +59,33 @@ system_reset_iSeries:
andc r4,r4,r5
mtspr SPRN_CTRLT,r4
+/* Spin on __secondary_hold_spinloop until it is updated by the boot cpu. */
+/* In the UP case we'll yeild() later, and we will not access the paca anyway
*/
+#ifdef CONFIG_SMP
1:
HMT_LOW
+ LOAD_REG_IMMEDIATE(r23, __secondary_hold_spinloop)
+ ld r23,0(r23)
+ sync
+ LOAD_REG_IMMEDIATE(r3,current_set)
+ sldi r28,r24,3 /* get current_set[cpu#] */
+ ldx r3,r3,r28
+ addi r1,r3,THREAD_SIZE
+ subi r1,r1,STACK_FRAME_OVERHEAD
+
+ cmpwi 0,r23,0 /* Keep poking the Hypervisor until */
+ bne 2f /* we're released */
+ /* Let the Hypervisor know we are alive */
+ /* 8002 is a call to HvCallCfg::getLps, a harmless Hypervisor function
*/
+ lis r3,0x8002
+ rldicr r3,r3,32,15 /* r0 = (r3 << 32) & 0xffff000000000000
*/
+ li r0,-1 /* r0=-1 indicates a Hypervisor call */
+ sc /* Invoke the hypervisor via a system
call */
+ b 1b
+#endif
+
+2:
+ HMT_LOW
#ifdef CONFIG_SMP
lbz r23,PACAPROCSTART(r13) /* Test if this processor
* should start */
@@ -91,7 +116,7 @@ iSeries_secondary_smp_loop:
li r0,-1 /* r0=-1 indicates a Hypervisor call */
sc /* Invoke the hypervisor via a system
call */
mfspr r13,SPRN_SPRG3 /* Put r13 back ???? */
- b 1b /* If SMP not configured, secondaries
+ b 2b /* If SMP not configured, secondaries
* loop forever */
/*** ISeries-LPAR interrupt handlers ***/
diff --git a/include/asm-powerpc/paca.h b/include/asm-powerpc/paca.h
index 2a05cc0..0bfc180 100644
--- a/include/asm-powerpc/paca.h
+++ b/include/asm-powerpc/paca.h
@@ -22,23 +22,6 @@
#include <asm/lppaca.h>
#include <asm/mmu.h>
-/*
- * iSeries needs the paca to be statically allocated and initialised.
- * We will allocated this many, based on NR_CPUS.
- */
-#if NR_CPUS > 32
-#define NR_STATIC_PACAS 64
-#elif NR_CPUS > 8
-#define NR_STATIC_PACAS 32
-#elif NR_CPUS > 4
-#define NR_STATIC_PACAS 8
-#elif NR_CPUS > 1
-#define NR_STATIC_PACAS 4
-#else
-#define NR_STATIC_PACAS 1
-#endif
-
-
register struct paca_struct *local_paca asm("r13");
#if defined(CONFIG_DEBUG_PREEMPT) && defined(CONFIG_SMP)
--
1.5.5.1
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