From 6212e3a388fdda3f19fa660ef5a30edf54d1dcfd Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Thu, 18 Oct 2007 03:04:56 -0700 Subject: [PATCH] Remove struct task_struct::io_wait Hell knows what happened in commit 63b05203af57e7de4f3bb63b8b81d43bc196d32b during 2.6.9 development. Commit introduced io_wait field which remained write-only than and still remains write-only. Also garbage collect macros which "use" io_wait. Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/aio.c | 16 ++-------------- include/linux/aio.h | 12 ------------ include/linux/sched.h | 7 ------- kernel/fork.c | 1 - 4 files changed, 2 insertions(+), 34 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index d02f43b50a3d..f12db415c0f6 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -710,18 +710,9 @@ static ssize_t aio_run_iocb(struct kiocb *iocb) /* * Now we are all set to call the retry method in async - * context. By setting this thread's io_wait context - * to point to the wait queue entry inside the currently - * running iocb for the duration of the retry, we ensure - * that async notification wakeups are queued by the - * operation instead of blocking waits, and when notified, - * cause the iocb to be kicked for continuation (through - * the aio_wake_function callback). + * context. */ - BUG_ON(current->io_wait != NULL); - current->io_wait = &iocb->ki_wait; ret = retry(iocb); - current->io_wait = NULL; if (ret != -EIOCBRETRY && ret != -EIOCBQUEUED) { BUG_ON(!list_empty(&iocb->ki_wait.task_list)); @@ -1508,10 +1499,7 @@ static ssize_t aio_setup_iocb(struct kiocb *kiocb) * Simply triggers a retry of the operation via kick_iocb. * * This callback is specified in the wait queue entry in - * a kiocb (current->io_wait points to this wait queue - * entry when an aio operation executes; it is used - * instead of a synchronous wait when an i/o blocking - * condition is encountered during aio). + * a kiocb. * * Note: * This routine is executed with the wait queue lock held. diff --git a/include/linux/aio.h b/include/linux/aio.h index d10e608f232d..7ef8de662001 100644 --- a/include/linux/aio.h +++ b/include/linux/aio.h @@ -232,18 +232,6 @@ int FASTCALL(io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb, __put_ioctx(kioctx); \ } while (0) -#define in_aio() (unlikely(!is_sync_wait(current->io_wait))) - -/* may be used for debugging */ -#define warn_if_async() \ -do { \ - if (in_aio()) { \ - printk(KERN_ERR "%s(%s:%d) called in async context!\n", \ - __FUNCTION__, __FILE__, __LINE__); \ - dump_stack(); \ - } \ -} while (0) - #define io_wait_to_kiocb(wait) container_of(wait, struct kiocb, ki_wait) #include diff --git a/include/linux/sched.h b/include/linux/sched.h index c204ab0d4df1..269b234609b8 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1110,13 +1110,6 @@ struct task_struct { unsigned long ptrace_message; siginfo_t *last_siginfo; /* For ptrace use. */ -/* - * current io wait handle: wait queue entry to use for io waits - * If this thread is processing aio, this points at the waitqueue - * inside the currently handled kiocb. It may be NULL (i.e. default - * to a stack based synchronous wait) if its doing sync IO. - */ - wait_queue_t *io_wait; #ifdef CONFIG_TASK_XACCT /* i/o counters(bytes read/written, #syscalls */ u64 rchar, wchar, syscr, syscw; diff --git a/kernel/fork.c b/kernel/fork.c index 7e455a93a75a..125246fc75a5 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1084,7 +1084,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->security = NULL; #endif p->io_context = NULL; - p->io_wait = NULL; p->audit_context = NULL; cpuset_fork(p); #ifdef CONFIG_NUMA