From 3e1d1d28d99dabe63c64f7f40f1ca1d646de1f73 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Fri, 24 Jun 2005 23:13:50 -0700 Subject: [PATCH] Cleanup patch for process freezing 1. Establish a simple API for process freezing defined in linux/include/sched.h: frozen(process) Check for frozen process freezing(process) Check if a process is being frozen freeze(process) Tell a process to freeze (go to refrigerator) thaw_process(process) Restart process frozen_process(process) Process is frozen now 2. Remove all references to PF_FREEZE and PF_FROZEN from all kernel sources except sched.h 3. Fix numerous locations where try_to_freeze is manually done by a driver 4. Remove the argument that is no longer necessary from two function calls. 5. Some whitespace cleanup 6. Clear potential race in refrigerator (provides an open window of PF_FREEZE cleared before setting PF_FROZEN, recalc_sigpending does not check PF_FROZEN). This patch does not address the problem of freeze_processes() violating the rule that a task may only modify its own flags by setting PF_FREEZE. This is not clean in an SMP environment. freeze(process) is therefore not SMP safe! Signed-off-by: Christoph Lameter Signed-off-by: Linus Torvalds --- fs/jfs/jfs_logmgr.c | 4 ++-- fs/jfs/jfs_txnmgr.c | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) (limited to 'fs/jfs') diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c index 7c8387ed419..79d07624bfe 100644 --- a/fs/jfs/jfs_logmgr.c +++ b/fs/jfs/jfs_logmgr.c @@ -2359,9 +2359,9 @@ int jfsIOWait(void *arg) lbmStartIO(bp); spin_lock_irq(&log_redrive_lock); } - if (current->flags & PF_FREEZE) { + if (freezing(current)) { spin_unlock_irq(&log_redrive_lock); - refrigerator(PF_FREEZE); + refrigerator(); } else { add_wait_queue(&jfs_IO_thread_wait, &wq); set_current_state(TASK_INTERRUPTIBLE); diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c index 8cbaaff1d5f..121c981ff45 100644 --- a/fs/jfs/jfs_txnmgr.c +++ b/fs/jfs/jfs_txnmgr.c @@ -2788,9 +2788,9 @@ int jfs_lazycommit(void *arg) /* In case a wakeup came while all threads were active */ jfs_commit_thread_waking = 0; - if (current->flags & PF_FREEZE) { + if (freezing(current)) { LAZY_UNLOCK(flags); - refrigerator(PF_FREEZE); + refrigerator(); } else { DECLARE_WAITQUEUE(wq, current); @@ -2987,9 +2987,9 @@ int jfs_sync(void *arg) /* Add anon_list2 back to anon_list */ list_splice_init(&TxAnchor.anon_list2, &TxAnchor.anon_list); - if (current->flags & PF_FREEZE) { + if (freezing(current)) { TXN_UNLOCK(); - refrigerator(PF_FREEZE); + refrigerator(); } else { DECLARE_WAITQUEUE(wq, current); -- cgit