• John David Anglin's avatar
    parisc: use spin_lock_irqsave/spin_unlock_irqrestore for PTE updates · bda079d3
    John David Anglin authored
    User applications running on SMP kernels have long suffered from instability
    and random segmentation faults.  This patch improves the situation although
    there is more work to be done.
    
    One of the problems is the various routines in pgtable.h that update page table
    entries use different locking mechanisms, or no lock at all (set_pte_at).  This
    change modifies the routines to all use the same lock pa_dbit_lock.  This lock
    is used for dirty bit updates in the interruption code. The patch also purges
    the TLB entries associated with the PTE to ensure that inconsistent values are
    not used after the page table entry is updated.  The UP and SMP code are now
    identical.
    
    The change also includes a minor update to the purge_tlb_entries function in
    cache.c to improve its efficiency.
    Signed-off-by: 's avatarJohn David Anglin <dave.anglin@bell.net>
    Cc: Helge Deller <deller@gmx.de>
    Signed-off-by: 's avatarHelge Deller <deller@gmx.de>
    bda079d3
cache.c 17.4 KB