Re: [4.4-rc6-rt1 PATCH 0/2] ARM: am437x: boot test report
From: Russell King - ARM Linux <hidden>
Date: 2016-01-14 21:30:58
Also in:
linux-arm-kernel, lkml
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
On Thu, Jan 14, 2016 at 10:11:09PM +0200, Grygorii Strashko wrote:
quoted hunk ↗ jump to hunk
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c index deabc36..b9b4f9c 100644 --- a/arch/arm/mm/highmem.c +++ b/arch/arm/mm/highmem.c@@ -167,7 +167,7 @@ void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) * Clear @prev's kmap_atomic mappings */ for (i = 0; i < prev_p->kmap_idx; i++) { - int idx = i + KM_TYPE_NR * smp_processor_id(); + int idx = FIX_KMAP_BEGIN + i + KM_TYPE_NR * smp_processor_id(); set_fixmap_pte(idx, __pte(0)); }@@ -175,7 +175,7 @@ void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) * Restore @next_p's kmap_atomic mappings */ for (i = 0; i < next_p->kmap_idx; i++) { - int idx = i + KM_TYPE_NR * smp_processor_id(); + int idx = FIX_KMAP_BEGIN + i + KM_TYPE_NR * smp_processor_id(); if (!pte_none(next_p->kmap_pte[i])) set_fixmap_pte(idx, next_p->kmap_pte[i]);
This looks like it introduces the 4th and 5th copies of the same calcuation, so can I suggest that we do this to prevent this kind of error?
diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index d02f8187b1cc..61f0d5941116 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c@@ -34,6 +34,11 @@ static inline pte_t get_fixmap_pte(unsigned long vaddr) return *ptep; } +static unsigned int fixmap_idx(int type) +{ + return FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); +} + void *kmap(struct page *page) { might_sleep();
@@ -79,7 +84,7 @@ void *kmap_atomic(struct page *page) type = kmap_atomic_idx_push(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); + idx = fixmap_idx(type); vaddr = __fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM /*
@@ -106,7 +111,7 @@ void __kunmap_atomic(void *kvaddr) if (kvaddr >= (void *)FIXADDR_START) { type = kmap_atomic_idx(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); + idx = fixmap_idx(type); if (cache_is_vivt()) __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
@@ -138,7 +143,7 @@ void *kmap_atomic_pfn(unsigned long pfn) return page_address(page); type = kmap_atomic_idx_push(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); + idx = fixmap_idx(type); vaddr = __fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(!pte_none(get_fixmap_pte(vaddr)));
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