From: Kemeng Shi <shikemeng@huawei.com> euleros inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I7RO5Q CVE: NA Reference: https://gitee.com/openeuler/kernel/commit/76cd04fa6fbe1bfca952d5bb6fb8ddd70f... ------------------------------------------------- Now, we will call cond_resched after scan a full memslot. If we scan a huge memslot, it will take long time before cond_resched. So call cond_resched after scan walk_step size memory. Signed-off-by: Kemeng Shi <shikemeng@huawei.com> Reviewed-by: louhongxiang <louhongxiang@huawei.com> Reviewed-by: Chen Wandun <chenwandun@huawei.com> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- fs/proc/etmem_scan.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/fs/proc/etmem_scan.c b/fs/proc/etmem_scan.c index 863bd61529f9..f3fff53b1411 100644 --- a/fs/proc/etmem_scan.c +++ b/fs/proc/etmem_scan.c @@ -106,6 +106,9 @@ static struct kernel_param_ops walk_step_ops = { static unsigned int __read_mostly walk_step = 512; // in PAGE_SIZE module_param_cb(walk_step, &walk_step_ops, &walk_step, 0644); +static unsigned int resched_step = 10; +module_param(resched_step, uint, 0644); + static unsigned long pagetype_size[16] = { [PTE_ACCESSED] = PAGE_SIZE, /* 4k page */ [PMD_ACCESSED] = PMD_SIZE, /* 2M page */ @@ -836,6 +839,7 @@ static int vm_idle_walk_hva_range(struct page_idle_ctrl *pic, unsigned long addr_range; unsigned long va_end; int ret; + int steps; #ifdef CONFIG_X86_64 ret = ept_idle_supports_cpu(pic->kvm); @@ -863,6 +867,7 @@ static int vm_idle_walk_hva_range(struct page_idle_ctrl *pic, } else { pic->gpa_to_hva = start - gpa_addr; gpa_end = gpa_addr + addr_range; + steps = 0; for (; gpa_addr < gpa_end;) { gpa_next = min(gpa_end, gpa_addr + walk_step * PAGE_SIZE); #ifdef CONFIG_ARM64 @@ -874,6 +879,11 @@ static int vm_idle_walk_hva_range(struct page_idle_ctrl *pic, if (ret) break; + + if (++steps >= resched_step) { + cond_resched(); + steps = 0; + } } va_end = pic->gpa_to_hva + gpa_end; } -- 2.27.0