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Message-ID: <7cd5d4b40601040240n79b2d654t33424e91059988a9@mail.gmail.com>
Date: Wed, 4 Jan 2006 18:40:54 +0800
From: jeff shia <tshxiayu@gmail.com>
To: linux-kernel@vger.kernel.org
Subject: what is the state of current after an mm_fault occurs?
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Hello,
       In my opinion, the state of current should be TASK_RUNNING
after an mm_fault occurs.But I donot know why the function of
handle_mm_fault() set the state of current TASK_RUNNING.
/*
 * By the time we get here, we already hold the mm semaphore
 */
int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct * vma,
	unsigned long address, int write_access)
{
	pgd_t *pgd;
	pmd_t *pmd;

	__set_current_state(TASK_RUNNING);
	pgd = pgd_offset(mm, address);

	inc_page_state(pgfault);

	if (is_vm_hugetlb_page(vma))
		return VM_FAULT_SIGBUS;	/* mapping truncation does this. */

	/*
	 * We need the page table lock to synchronize with kswapd
	 * and the SMP-safe atomic PTE updates.
	 */
	spin_lock(&mm->page_table_lock);
	pmd = pmd_alloc(mm, pgd, address);

	if (pmd) {
		pte_t * pte = pte_alloc_map(mm, pmd, address);
		if (pte)
			return handle_pte_fault(mm, vma, address, write_access, pte, pmd);
	}
	spin_unlock(&mm->page_table_lock);
	return VM_FAULT_OOM;
}

any help will be preferred.
Thank you!!

Jeff
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