summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/arm/include/asm/smp_plat.h3
-rw-r--r--arch/arm/include/asm/spinlock.h51
-rw-r--r--arch/arm/kernel/entry-armv.S3
-rw-r--r--arch/arm/kernel/fiq.c8
-rw-r--r--arch/arm/kernel/machine_kexec.c20
-rw-r--r--arch/arm/kernel/perf_event.c5
-rw-r--r--arch/arm/kernel/process.c2
-rw-r--r--arch/arm/kernel/smp.c10
8 files changed, 69 insertions, 33 deletions
diff --git a/arch/arm/include/asm/smp_plat.h b/arch/arm/include/asm/smp_plat.h
index 6462a721ebd4..a252c0bfacf5 100644
--- a/arch/arm/include/asm/smp_plat.h
+++ b/arch/arm/include/asm/smp_plat.h
@@ -88,4 +88,7 @@ static inline u32 mpidr_hash_size(void)
{
return 1 << mpidr_hash.bits;
}
+
+extern int platform_can_cpu_hotplug(void);
+
#endif
diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h
index f8b8965666e9..b07c09e5a0ac 100644
--- a/arch/arm/include/asm/spinlock.h
+++ b/arch/arm/include/asm/spinlock.h
@@ -107,7 +107,7 @@ static inline int arch_spin_trylock(arch_spinlock_t *lock)
" subs %1, %0, %0, ror #16\n"
" addeq %0, %0, %4\n"
" strexeq %2, %0, [%3]"
- : "=&r" (slock), "=&r" (contended), "=r" (res)
+ : "=&r" (slock), "=&r" (contended), "=&r" (res)
: "r" (&lock->slock), "I" (1 << TICKET_SHIFT)
: "cc");
} while (res);
@@ -168,17 +168,20 @@ static inline void arch_write_lock(arch_rwlock_t *rw)
static inline int arch_write_trylock(arch_rwlock_t *rw)
{
- unsigned long tmp;
+ unsigned long contended, res;
- __asm__ __volatile__(
-" ldrex %0, [%1]\n"
-" teq %0, #0\n"
-" strexeq %0, %2, [%1]"
- : "=&r" (tmp)
- : "r" (&rw->lock), "r" (0x80000000)
- : "cc");
+ do {
+ __asm__ __volatile__(
+ " ldrex %0, [%2]\n"
+ " mov %1, #0\n"
+ " teq %0, #0\n"
+ " strexeq %1, %3, [%2]"
+ : "=&r" (contended), "=&r" (res)
+ : "r" (&rw->lock), "r" (0x80000000)
+ : "cc");
+ } while (res);
- if (tmp == 0) {
+ if (!contended) {
smp_mb();
return 1;
} else {
@@ -254,18 +257,26 @@ static inline void arch_read_unlock(arch_rwlock_t *rw)
static inline int arch_read_trylock(arch_rwlock_t *rw)
{
- unsigned long tmp, tmp2 = 1;
+ unsigned long contended, res;
- __asm__ __volatile__(
-" ldrex %0, [%2]\n"
-" adds %0, %0, #1\n"
-" strexpl %1, %0, [%2]\n"
- : "=&r" (tmp), "+r" (tmp2)
- : "r" (&rw->lock)
- : "cc");
+ do {
+ __asm__ __volatile__(
+ " ldrex %0, [%2]\n"
+ " mov %1, #0\n"
+ " adds %0, %0, #1\n"
+ " strexpl %1, %0, [%2]"
+ : "=&r" (contended), "=&r" (res)
+ : "r" (&rw->lock)
+ : "cc");
+ } while (res);
- smp_mb();
- return tmp2 == 0;
+ /* If the lock is negative, then it is already held for write. */
+ if (contended < 0x80000000) {
+ smp_mb();
+ return 1;
+ } else {
+ return 0;
+ }
}
/* read_can_lock - would read_trylock() succeed? */
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index d40d0ef389db..9cbe70c8b0ef 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -357,7 +357,8 @@ ENDPROC(__pabt_svc)
.endm
.macro kuser_cmpxchg_check
-#if !defined(CONFIG_CPU_32v6K) && !defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG)
+#if !defined(CONFIG_CPU_32v6K) && defined(CONFIG_KUSER_HELPERS) && \
+ !defined(CONFIG_NEEDS_SYSCALL_FOR_CMPXCHG)
#ifndef CONFIG_MMU
#warning "NPTL on non MMU needs fixing"
#else
diff --git a/arch/arm/kernel/fiq.c b/arch/arm/kernel/fiq.c
index 25442f451148..fc7920288a3d 100644
--- a/arch/arm/kernel/fiq.c
+++ b/arch/arm/kernel/fiq.c
@@ -84,17 +84,13 @@ int show_fiq_list(struct seq_file *p, int prec)
void set_fiq_handler(void *start, unsigned int length)
{
-#if defined(CONFIG_CPU_USE_DOMAINS)
- void *base = (void *)0xffff0000;
-#else
void *base = vectors_page;
-#endif
unsigned offset = FIQ_OFFSET;
memcpy(base + offset, start, length);
+ if (!cache_is_vipt_nonaliasing())
+ flush_icache_range(base + offset, offset + length);
flush_icache_range(0xffff0000 + offset, 0xffff0000 + offset + length);
- if (!vectors_high())
- flush_icache_range(offset, offset + length);
}
int claim_fiq(struct fiq_handler *f)
diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
index 4fb074c446bf..d7c82df69243 100644
--- a/arch/arm/kernel/machine_kexec.c
+++ b/arch/arm/kernel/machine_kexec.c
@@ -15,6 +15,7 @@
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
#include <asm/mach-types.h>
+#include <asm/smp_plat.h>
#include <asm/system_misc.h>
extern const unsigned char relocate_new_kernel[];
@@ -39,6 +40,14 @@ int machine_kexec_prepare(struct kimage *image)
int i, err;
/*
+ * Validate that if the current HW supports SMP, then the SW supports
+ * and implements CPU hotplug for the current HW. If not, we won't be
+ * able to kexec reliably, so fail the prepare operation.
+ */
+ if (num_possible_cpus() > 1 && !platform_can_cpu_hotplug())
+ return -EINVAL;
+
+ /*
* No segment at default ATAGs address. try to locate
* a dtb using magic.
*/
@@ -134,10 +143,13 @@ void machine_kexec(struct kimage *image)
unsigned long reboot_code_buffer_phys;
void *reboot_code_buffer;
- if (num_online_cpus() > 1) {
- pr_err("kexec: error: multiple CPUs still online\n");
- return;
- }
+ /*
+ * This can only happen if machine_shutdown() failed to disable some
+ * CPU, and that can only happen if the checks in
+ * machine_kexec_prepare() were not correct. If this fails, we can't
+ * reliably kexec anyway, so BUG_ON is appropriate.
+ */
+ BUG_ON(num_online_cpus() > 1);
page_list = image->head & PAGE_MASK;
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 21f77906602c..e186ee1e63f6 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -56,7 +56,7 @@ armpmu_map_hw_event(const unsigned (*event_map)[PERF_COUNT_HW_MAX], u64 config)
int mapping;
if (config >= PERF_COUNT_HW_MAX)
- return -ENOENT;
+ return -EINVAL;
mapping = (*event_map)[config];
return mapping == HW_OP_UNSUPPORTED ? -ENOENT : mapping;
@@ -258,6 +258,9 @@ validate_event(struct pmu_hw_events *hw_events,
struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
struct pmu *leader_pmu = event->group_leader->pmu;
+ if (is_software_event(event))
+ return 1;
+
if (event->pmu != leader_pmu || event->state < PERF_EVENT_STATE_OFF)
return 1;
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 536c85fe72a8..94f6b05f9e24 100644
--- a/arch/arm/kernel/process.c
+++ b/arch/arm/kernel/process.c
@@ -462,7 +462,7 @@ int in_gate_area_no_mm(unsigned long addr)
{
return in_gate_area(NULL, addr);
}
-#define is_gate_vma(vma) ((vma) = &gate_vma)
+#define is_gate_vma(vma) ((vma) == &gate_vma)
#else
#define is_gate_vma(vma) 0
#endif
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index c2b4f8f0be9a..2dc19349eb19 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -145,6 +145,16 @@ int boot_secondary(unsigned int cpu, struct task_struct *idle)
return -ENOSYS;
}
+int platform_can_cpu_hotplug(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ if (smp_ops.cpu_kill)
+ return 1;
+#endif
+
+ return 0;
+}
+
#ifdef CONFIG_HOTPLUG_CPU
static void percpu_timer_stop(void);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-19 05:50:01 +0100