BMC/Intel-BMC/linux.git/arch/arm/mm/flush.c, branch dev

ARM: 8237/1: fix flush_pfn_alias

2014-12-03T16:00:04+00:00

L1_CACHE_BYTES could be larger than real L1 cache line size. In that case, flush_pfn_alias() would omit to flush last bytes as much as L1_CACHE_BYTES - real cache line size. So fix end address to "to + PAGE_SIZE - 1". The bottom bits of the address is LINELEN. that is ignored by mcrr. Signed-off-by: Jungseung Lee Signed-off-by: Russell King

arm: mm: enable RCU fast_gup

2014-10-10T02:26:01+00:00

Activate the RCU fast_gup for ARM. We also need to force THP splits to broadcast an IPI s.t. we block in the fast_gup page walker. As THP splits are comparatively rare, this should not lead to a noticeable performance degradation. Some pre-requisite functions pud_write and pud_page are also added. Signed-off-by: Steve Capper Reviewed-by: Catalin Marinas Cc: Dann Frazier Cc: Hugh Dickins Cc: Russell King Cc: Mark Rutland Cc: Mel Gorman Cc: Will Deacon Cc: Christoffer Dall Cc: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ARM: 8043/1: uprobes need icache flush after xol write

2014-05-25T22:48:45+00:00

After instruction write into xol area, on ARM V7 architecture code need to flush dcache and icache to sync them up for given set of addresses. Having just 'flush_dcache_page(page)' call is not enough - it is possible to have stale instruction sitting in icache for given xol area slot address. Introduce arch_uprobe_ixol_copy weak function that by default calls uprobes copy_to_page function and than flush_dcache_page function and on ARM define new one that handles xol slot copy in ARM specific way flush_uprobe_xol_access function shares/reuses implementation with/of flush_ptrace_access function and takes care of writing instruction to user land address space on given variety of different cache types on ARM CPUs. Because flush_uprobe_xol_access does not have vma around flush_ptrace_access was split into two parts. First that retrieves set of condition from vma and common that receives those conditions as flags. Note ARM cache flush function need kernel address through which instruction write happened, so instead of using uprobes copy_to_page function changed code to explicitly map page and do memcpy. Note arch_uprobe_copy_ixol function, in similar way as copy_to_user_page function, has preempt_disable/preempt_enable. Signed-off-by: Victor Kamensky Acked-by: Oleg Nesterov Reviewed-by: David A. Long Signed-off-by: Russell King

ARM: 7923/1: mm: fix dcache flush logic for compound high pages

2013-12-29T12:46:08+00:00

When given a compound high page, __flush_dcache_page will only flush the first page of the compound page repeatedly rather than the entire set of constituent pages. This error was introduced by: 0b19f93 ARM: mm: Add support for flushing HugeTLB pages. This patch corrects the logic such that all constituent pages are now flushed. Cc: stable@vger.kernel.org # 3.10+ Signed-off-by: Steve Capper Acked-by: Will Deacon Signed-off-by: Russell King

Merge branch 'devel-stable' into for-next

2013-06-29T10:44:43+00:00

Conflicts: arch/arm/Makefile arch/arm/include/asm/glue-proc.h

Merge branches 'fixes', 'mcpm', 'misc' and 'mmci' into for-next

2013-06-29T10:43:28+00:00

ARM: 7755/1: handle user space mapped pages in flush_kernel_dcache_page

2013-06-17T09:30:52+00:00

Commit f8b63c1 made flush_kernel_dcache_page a no-op assuming that the pages it needs to handle are kernel mapped only. However, for example when doing direct I/O, pages with user space mappings may occur. Thus, continue to do lazy flushing if there are no user space mappings. Otherwise, flush the kernel cache lines directly. Signed-off-by: Simon Baatz Reviewed-by: Catalin Marinas Cc: # 3.2+ Signed-off-by: Russell King

ARM: 7746/1: mm: lazy cache flushing on non-mapped pages

2013-06-05T22:37:32+00:00

Currently flush_dcache_page() thinks pages as non-mapped if mapping_mapped(mapping) return false. This approach is very coase: - mmap on part of file may cause all pages backed on the file being thought as mmaped - file-backed pages aren't mapped into user space actually if the memory mmaped on the file isn't accessed This patch uses page_mapped() to decide if the page has been mapped. From the attached test code, I find there is much performance improvement(>25%) when accessing page caches via read under this situations, so memcpy benefits a lot from not flushing cache under this situation. No. read time without the patch No. read time with the patch ================================================================ No. 0, time 22615636 us No. 0, time 22014717 us No. 1, time 4387851 us No. 1, time 3113184 us No. 2, time 4276535 us No. 2, time 3005244 us No. 3, time 4259821 us No. 3, time 3001565 us No. 4, time 4263811 us No. 4, time 3002748 us No. 5, time 4258486 us No. 5, time 3004104 us No. 6, time 4253009 us No. 6, time 3002188 us No. 7, time 4262809 us No. 7, time 2998196 us No. 8, time 4264525 us No. 8, time 3007255 us No. 9, time 4267795 us No. 9, time 3005094 us 1), No.0. is to read the file from storage device, and others are to read the file from page caches basically. 2), file size is 512M, and is on ext4 over usb mass storage. 3), the test is done on Pandaboard. unsigned int sum = 0; unsigned long sum_val = 0; static unsigned long tv_diff(struct timeval *tv1, struct timeval *tv2) { return (tv2->tv_sec - tv1->tv_sec) * 1000000 + (tv2->tv_usec - tv1->tv_usec); } int main(int argc, char *argv[]) { char *mbuf, fbuf; int fd; int i; unsigned long page_size, size; struct stat stat; struct timeval t1, t2; unsigned char *rbuf = malloc(32 * page_size); if (!rbuf) { printf(" %sn", "malloc failed"); exit(-1); } page_size = getpagesize(); fd = open(argv[1], O_RDWR); assert(fd >= 0); fstat(fd, &stat); size = stat.st_size; printf("%s: file %s, size %lu, page size %lun", argv[0], argv[1], size, page_size); gettimeofday(&t1, NULL); mbuf = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); if (!mbuf) { printf(" %sn", "mmap failed"); exit(-1); } for (i = 0 ; i < size ; i += (page_size * 32)) { int rcnt; lseek(fd, i, SEEK_SET); rcnt = read(fd, rbuf, page_size * 32); if (rcnt != page_size * 32) { printf("%s: read faildn", __func__); exit(-1); } } free(rbuf); munmap(mbuf, size); gettimeofday(&t2, NULL); printf("tread mmaped time: %luusn", tv_diff(&t1, &t2)); close(fd); } Cc: Michel Lespinasse Cc: Andrew Morton Cc: Nicolas Pitre Reviewed-by: Will Deacon Acked-by: Catalin Marinas Signed-off-by: Ming Lei Signed-off-by: Russell King

ARM: mm: Add support for flushing HugeTLB pages.

2013-06-04T15:52:37+00:00

On ARM we use the __flush_dcache_page function to flush the dcache of pages when needed; usually when the PG_dcache_clean bit is unset and we are setting a PTE. A HugeTLB page is represented as a compound page consisting of an array of pages. Thus to flush the dcache of a HugeTLB page, one must flush more than a single page. This patch modifies __flush_dcache_page such that all constituent pages of a HugeTLB page are flushed. Signed-off-by: Steve Capper Reviewed-by: Will Deacon

ARM: 7693/1: mm: clean-up in order to reduce to call kmap_high_get()

2013-04-17T15:55:01+00:00

In kmap_atomic(), kmap_high_get() is invoked for checking already mapped area. In __flush_dcache_page() and dma_cache_maint_page(), we explicitly call kmap_high_get() before kmap_atomic() when cache_is_vipt(), so kmap_high_get() can be invoked twice. This is useless operation, so remove one. v2: change cache_is_vipt() to cache_is_vipt_nonaliasing() in order to be self-documented Acked-by: Nicolas Pitre Signed-off-by: Joonsoo Kim Signed-off-by: Russell King