From mboxrd@z Thu Jan 1 00:00:00 1970 Message-Id: <20070504103156.057213163@chello.nl> References: <20070504102651.923946304@chello.nl> Date: Fri, 04 May 2007 12:26:54 +0200 From: Peter Zijlstra Subject: [PATCH 03/40] mm: allow PF_MEMALLOC from softirq context Content-Disposition: inline; filename=mm-PF_MEMALLOC-softirq.patch Sender: owner-linux-mm@kvack.org Return-Path: To: linux-kernel@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org Cc: Peter Zijlstra , Trond Myklebust , Thomas Graf , David Miller , James Bottomley , Mike Christie , Andrew Morton , Daniel Phillips List-ID: Allow PF_MEMALLOC to be set in softirq context. When running softirqs from a borrowed context save current->flags, ksoftirqd will have its own task_struct. Signed-off-by: Peter Zijlstra --- include/linux/sched.h | 4 ++++ kernel/softirq.c | 3 +++ mm/internal.h | 7 ++++--- 3 files changed, 11 insertions(+), 3 deletions(-) Index: linux-2.6-git/mm/internal.h =================================================================== --- linux-2.6-git.orig/mm/internal.h 2007-02-22 14:44:37.000000000 +0100 +++ linux-2.6-git/mm/internal.h 2007-02-22 15:16:58.000000000 +0100 @@ -75,9 +75,10 @@ static int inline gfp_to_alloc_flags(gfp alloc_flags |= ALLOC_HARDER; if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) { - if (!in_interrupt() && - ((p->flags & PF_MEMALLOC) || - unlikely(test_thread_flag(TIF_MEMDIE)))) + if (!in_irq() && (p->flags & PF_MEMALLOC)) + alloc_flags |= ALLOC_NO_WATERMARKS; + else if (!in_interrupt() && + unlikely(test_thread_flag(TIF_MEMDIE))) alloc_flags |= ALLOC_NO_WATERMARKS; } Index: linux-2.6-git/kernel/softirq.c =================================================================== --- linux-2.6-git.orig/kernel/softirq.c 2007-02-22 14:44:35.000000000 +0100 +++ linux-2.6-git/kernel/softirq.c 2007-02-22 15:29:38.000000000 +0100 @@ -210,6 +210,8 @@ asmlinkage void __do_softirq(void) __u32 pending; int max_restart = MAX_SOFTIRQ_RESTART; int cpu; + unsigned long pflags = current->flags; + current->flags &= ~PF_MEMALLOC; pending = local_softirq_pending(); account_system_vtime(current); @@ -248,6 +250,7 @@ restart: account_system_vtime(current); _local_bh_enable(); + tsk_restore_flags(current, pflags, PF_MEMALLOC); } #ifndef __ARCH_HAS_DO_SOFTIRQ Index: linux-2.6-git/include/linux/sched.h =================================================================== --- linux-2.6-git.orig/include/linux/sched.h 2007-02-22 15:17:39.000000000 +0100 +++ linux-2.6-git/include/linux/sched.h 2007-02-22 15:29:05.000000000 +0100 @@ -1185,6 +1185,10 @@ static inline void put_task_struct(struc #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) #define used_math() tsk_used_math(current) +#define tsk_restore_flags(p, pflags, mask) \ + do { (p)->flags &= ~(mask); \ + (p)->flags |= ((pflags) & (mask)); } while (0) + #ifdef CONFIG_SMP extern int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask); #else -- -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org