From 585fa72493edd7d5acb308806e7bb609412c6228 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Sat, 12 Aug 2006 16:40:08 +0100 Subject: [PATCH] [MIPS] Retire flush_icache_page from mm use. On the 34K the redundant cache operations were causing excessive stalls resulting in realtime code running on the second VPE missing its deadline. For all other platforms this patch is just a significant performance improvment as illustrated by below benchmark numbers. Processor, Processes - times in microseconds - smaller is better ------------------------------------------------------------------------------ Host OS Mhz null null open slct sig sig fork exec sh call I/O stat clos TCP inst hndl proc proc proc --------- ------------- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- 25Kf 2.6.18-rc4 533 0.49 1.16 7.57 33.4 30.5 1.34 12.4 5497 17.K 54.K 25Kf 2.6.18-rc4-p 533 0.49 1.16 6.68 23.0 30.7 1.36 8.55 5030 16.K 48.K 4Kc 2.6.18-rc4 80 4.21 15.0 131. 289. 261. 16.5 258. 18.K 70.K 227K 4Kc 2.6.18-rc4-p 80 4.34 13.1 128. 285. 262. 18.2 258. 12.K 52.K 176K 34Kc 2.6.18-rc4 40 5.01 14.0 61.6 90.0 477. 17.9 94.7 29.K 108K 342K 34Kc 2.6.18-rc4-p 40 4.98 13.9 61.2 89.7 475. 17.6 93.7 8758 44.K 158K BCM1480 2.6.18-rc4 700 0.28 0.60 3.68 5.92 16.0 0.78 5.08 931. 3163 15.K BCM1480 2.6.18-rc4-p 700 0.28 0.61 3.65 5.85 16.0 0.79 5.20 395. 1464 8385 TX49-16K 2.6.18-rc3 197 0.73 2.41 19.0 37.8 82.9 2.94 17.5 4438 14.K 56.K TX49-16K 2.6.18-rc3-p 197 0.73 2.40 19.9 36.3 82.9 2.94 23.4 2577 9103 38.K TX49-32K 2.6.18-rc3 396 0.36 1.19 6.80 11.8 41.0 1.46 8.17 2738 8465 32.K TX49-32K 2.6.18-rc3-p 396 0.36 1.19 6.82 10.2 41.0 1.46 8.18 1330 4638 18.K Original patch by me with enhancements by Atsushi Nemoto. Signed-off-by: Ralf Baechle Signed-off-by: Atsushi Nemoto --- arch/mips/mm/c-r3k.c | 2 +- arch/mips/mm/c-r4k.c | 2 +- arch/mips/mm/c-sb1.c | 2 +- arch/mips/mm/c-tx39.c | 4 ++-- arch/mips/mm/cache.c | 18 ++++++++++-------- include/asm-mips/cacheflush.h | 12 ++++++++---- include/asm-mips/page.h | 7 +++++-- 7 files changed, 28 insertions(+), 19 deletions(-) diff --git a/arch/mips/mm/c-r3k.c b/arch/mips/mm/c-r3k.c index bb041a22f2..e1f35ef811 100644 --- a/arch/mips/mm/c-r3k.c +++ b/arch/mips/mm/c-r3k.c @@ -335,7 +335,7 @@ void __init r3k_cache_init(void) flush_cache_mm = r3k_flush_cache_mm; flush_cache_range = r3k_flush_cache_range; flush_cache_page = r3k_flush_cache_page; - flush_icache_page = r3k_flush_icache_page; + __flush_icache_page = r3k_flush_icache_page; flush_icache_range = r3k_flush_icache_range; flush_cache_sigtramp = r3k_flush_cache_sigtramp; diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c index b3ccb8738d..4e14982463 100644 --- a/arch/mips/mm/c-r4k.c +++ b/arch/mips/mm/c-r4k.c @@ -1291,7 +1291,7 @@ void __init r4k_cache_init(void) __flush_cache_all = r4k___flush_cache_all; flush_cache_mm = r4k_flush_cache_mm; flush_cache_page = r4k_flush_cache_page; - flush_icache_page = r4k_flush_icache_page; + __flush_icache_page = r4k_flush_icache_page; flush_cache_range = r4k_flush_cache_range; flush_cache_sigtramp = r4k_flush_cache_sigtramp; diff --git a/arch/mips/mm/c-sb1.c b/arch/mips/mm/c-sb1.c index 2d71efb82a..4bd9ad8a5e 100644 --- a/arch/mips/mm/c-sb1.c +++ b/arch/mips/mm/c-sb1.c @@ -520,7 +520,7 @@ void sb1_cache_init(void) /* These routines are for Icache coherence with the Dcache */ flush_icache_range = sb1_flush_icache_range; - flush_icache_page = sb1_flush_icache_page; + __flush_icache_page = sb1_flush_icache_page; flush_icache_all = __sb1_flush_icache_all; /* local only */ /* This implies an Icache flush too, so can't be nop'ed */ diff --git a/arch/mips/mm/c-tx39.c b/arch/mips/mm/c-tx39.c index 5dfc9b1901..932a09d7ef 100644 --- a/arch/mips/mm/c-tx39.c +++ b/arch/mips/mm/c-tx39.c @@ -382,7 +382,7 @@ void __init tx39_cache_init(void) flush_cache_mm = (void *) tx39h_flush_icache_all; flush_cache_range = (void *) tx39h_flush_icache_all; flush_cache_page = (void *) tx39h_flush_icache_all; - flush_icache_page = (void *) tx39h_flush_icache_all; + __flush_icache_page = (void *) tx39h_flush_icache_all; flush_icache_range = (void *) tx39h_flush_icache_all; flush_cache_sigtramp = (void *) tx39h_flush_icache_all; @@ -408,7 +408,7 @@ void __init tx39_cache_init(void) flush_cache_mm = tx39_flush_cache_mm; flush_cache_range = tx39_flush_cache_range; flush_cache_page = tx39_flush_cache_page; - flush_icache_page = tx39_flush_icache_page; + __flush_icache_page = tx39_flush_icache_page; flush_icache_range = tx39_flush_icache_range; flush_cache_sigtramp = tx39_flush_cache_sigtramp; diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c index ddd3a2de1d..40c8b02351 100644 --- a/arch/mips/mm/cache.c +++ b/arch/mips/mm/cache.c @@ -25,7 +25,7 @@ void (*flush_cache_range)(struct vm_area_struct *vma, unsigned long start, void (*flush_cache_page)(struct vm_area_struct *vma, unsigned long page, unsigned long pfn); void (*flush_icache_range)(unsigned long start, unsigned long end); -void (*flush_icache_page)(struct vm_area_struct *vma, struct page *page); +void (*__flush_icache_page)(struct vm_area_struct *vma, struct page *page); /* MIPS specific cache operations */ void (*flush_cache_sigtramp)(unsigned long addr); @@ -70,6 +70,8 @@ void __flush_dcache_page(struct page *page) struct address_space *mapping = page_mapping(page); unsigned long addr; + if (PageHighMem(page)) + return; if (mapping && !mapping_mapped(mapping)) { SetPageDcacheDirty(page); return; @@ -91,16 +93,16 @@ void __update_cache(struct vm_area_struct *vma, unsigned long address, { struct page *page; unsigned long pfn, addr; + int exec = (vma->vm_flags & VM_EXEC) && !cpu_has_ic_fills_f_dc; pfn = pte_pfn(pte); - if (pfn_valid(pfn) && (page = pfn_to_page(pfn), page_mapping(page)) && - Page_dcache_dirty(page)) { - if (pages_do_alias((unsigned long)page_address(page), - address & PAGE_MASK)) { - addr = (unsigned long) page_address(page); + if (unlikely(!pfn_valid(pfn))) + return; + page = pfn_to_page(pfn); + if (page_mapping(page) && Page_dcache_dirty(page)) { + addr = (unsigned long) page_address(page); + if (exec || pages_do_alias(addr, address & PAGE_MASK)) flush_data_cache_page(addr); - } - ClearPageDcacheDirty(page); } } diff --git a/include/asm-mips/cacheflush.h b/include/asm-mips/cacheflush.h index 47bc8f6c20..36416fdfcf 100644 --- a/include/asm-mips/cacheflush.h +++ b/include/asm-mips/cacheflush.h @@ -21,7 +21,6 @@ * - flush_cache_range(vma, start, end) flushes a range of pages * - flush_icache_range(start, end) flush a range of instructions * - flush_dcache_page(pg) flushes(wback&invalidates) a page for dcache - * - flush_icache_page(vma, pg) flushes(invalidates) a page for icache * * MIPS specific flush operations: * @@ -39,7 +38,7 @@ extern void __flush_dcache_page(struct page *page); static inline void flush_dcache_page(struct page *page) { - if (cpu_has_dc_aliases) + if (cpu_has_dc_aliases || !cpu_has_ic_fills_f_dc) __flush_dcache_page(page); } @@ -47,8 +46,13 @@ static inline void flush_dcache_page(struct page *page) #define flush_dcache_mmap_lock(mapping) do { } while (0) #define flush_dcache_mmap_unlock(mapping) do { } while (0) -extern void (*flush_icache_page)(struct vm_area_struct *vma, +extern void (*__flush_icache_page)(struct vm_area_struct *vma, struct page *page); +static inline void flush_icache_page(struct vm_area_struct *vma, + struct page *page) +{ +} + extern void (*flush_icache_range)(unsigned long start, unsigned long end); #define flush_cache_vmap(start, end) flush_cache_all() #define flush_cache_vunmap(start, end) flush_cache_all() @@ -60,7 +64,7 @@ static inline void copy_to_user_page(struct vm_area_struct *vma, if (cpu_has_dc_aliases) flush_cache_page(vma, vaddr, page_to_pfn(page)); memcpy(dst, src, len); - flush_icache_page(vma, page); + __flush_icache_page(vma, page); } static inline void copy_from_user_page(struct vm_area_struct *vma, diff --git a/include/asm-mips/page.h b/include/asm-mips/page.h index 219d359861..c3b872b047 100644 --- a/include/asm-mips/page.h +++ b/include/asm-mips/page.h @@ -34,6 +34,8 @@ #ifndef __ASSEMBLY__ +#include + extern void clear_page(void * page); extern void copy_page(void * to, void * from); @@ -53,7 +55,7 @@ static inline void clear_user_page(void *addr, unsigned long vaddr, extern void (*flush_data_cache_page)(unsigned long addr); clear_page(addr); - if (pages_do_alias((unsigned long) addr, vaddr)) + if (pages_do_alias((unsigned long) addr, vaddr & PAGE_MASK)) flush_data_cache_page((unsigned long)addr); } @@ -63,7 +65,8 @@ static inline void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, extern void (*flush_data_cache_page)(unsigned long addr); copy_page(vto, vfrom); - if (pages_do_alias((unsigned long)vto, vaddr)) + if (!cpu_has_ic_fills_f_dc || + pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) flush_data_cache_page((unsigned long)vto); } -- 2.39.5