On 3/8/07, Eric Dumazet <[EMAIL PROTECTED]> wrote:
Absolutely not. We dont want to slow down kernel 'just in case a fool might want to do crazy things'
Actually, I think it would make the kernel (negligibly) faster to bump f_pos before the vfs_write() call. Unless fget_light sets fput_needed or the write doesn't complete cleanly, you won't have to touch the file table entry again after vfs_write() returns. You can adjust vfs_write to grab f_dentry out of the file before going into do_sync_write. do_sync_write is done with the struct file before it goes into the aio_write() loop. Result: you probably save at least an L1 cache miss, unless the aio_write loop is so frugal with L1 cache that it doesn't manage to evict the struct file. Patch to follow. Cheers, - Michael - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
