From 4dd53d891ca46dcc1fde0376a33540d3fd83cb9a Mon Sep 17 00:00:00 2001 From: Venkatesh Pallipadi Date: Tue, 21 Dec 2010 17:09:00 -0800 Subject: [PATCH] softirqs: Free up pf flag PF_KSOFTIRQD Cleanup patch, freeing up PF_KSOFTIRQD and use per_cpu ksoftirqd pointer instead, as suggested by Eric Dumazet. Tested-by: Shaun Ruffell Signed-off-by: Venkatesh Pallipadi Signed-off-by: Peter Zijlstra LKML-Reference: <1292980144-28796-2-git-send-email-venki@google.com> Signed-off-by: Ingo Molnar --- include/linux/interrupt.h | 7 +++++++ include/linux/sched.h | 1 - kernel/sched.c | 2 +- kernel/softirq.c | 3 +-- 4 files changed, 9 insertions(+), 4 deletions(-) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 55e0d4253e49..a1382b9b5813 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -426,6 +426,13 @@ extern void raise_softirq(unsigned int nr); */ DECLARE_PER_CPU(struct list_head [NR_SOFTIRQS], softirq_work_list); +DECLARE_PER_CPU(struct task_struct *, ksoftirqd); + +static inline struct task_struct *this_cpu_ksoftirqd(void) +{ + return this_cpu_read(ksoftirqd); +} + /* Try to send a softirq to a remote cpu. If this cannot be done, the * work will be queued to the local cpu. */ diff --git a/include/linux/sched.h b/include/linux/sched.h index d747f948b34e..af6e15fbfb78 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1715,7 +1715,6 @@ extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t * /* * Per process flags */ -#define PF_KSOFTIRQD 0x00000001 /* I am ksoftirqd */ #define PF_STARTING 0x00000002 /* being created */ #define PF_EXITING 0x00000004 /* getting shut down */ #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ diff --git a/kernel/sched.c b/kernel/sched.c index 6820b5b3a969..8b89b3bba565 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -1880,7 +1880,7 @@ void account_system_vtime(struct task_struct *curr) */ if (hardirq_count()) __this_cpu_add(cpu_hardirq_time, delta); - else if (in_serving_softirq() && !(curr->flags & PF_KSOFTIRQD)) + else if (in_serving_softirq() && curr != this_cpu_ksoftirqd()) __this_cpu_add(cpu_softirq_time, delta); irq_time_write_end(); diff --git a/kernel/softirq.c b/kernel/softirq.c index 68eb5efec388..0cee50487629 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -54,7 +54,7 @@ EXPORT_SYMBOL(irq_stat); static struct softirq_action softirq_vec[NR_SOFTIRQS] __cacheline_aligned_in_smp; -static DEFINE_PER_CPU(struct task_struct *, ksoftirqd); +DEFINE_PER_CPU(struct task_struct *, ksoftirqd); char *softirq_to_name[NR_SOFTIRQS] = { "HI", "TIMER", "NET_TX", "NET_RX", "BLOCK", "BLOCK_IOPOLL", @@ -721,7 +721,6 @@ static int run_ksoftirqd(void * __bind_cpu) { set_current_state(TASK_INTERRUPTIBLE); - current->flags |= PF_KSOFTIRQD; while (!kthread_should_stop()) { preempt_disable(); if (!local_softirq_pending()) {