tcp: make tcp_space() aware of socket backlog

[mirror_ubuntu-bionic-kernel.git] / kernel / softirq.c

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 2f5e87f1bae22f3df44fa4493fcc8b255882267f..f61113f6b51df7e66609f6bebb779b752751d242 100644 (file)
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -79,12 +79,16 @@ static void wakeup_softirqd(void)
 
 /*
  * If ksoftirqd is scheduled, we do not want to process pending softirqs
- * right now. Let ksoftirqd handle this at its own rate, to get fairness.
+ * right now. Let ksoftirqd handle this at its own rate, to get fairness,
+ * unless we're doing some of the synchronous softirqs.
  */
-static bool ksoftirqd_running(void)
+#define SOFTIRQ_NOW_MASK ((1 << HI_SOFTIRQ) | (1 << TASKLET_SOFTIRQ))
+static bool ksoftirqd_running(unsigned long pending)
 {
        struct task_struct *tsk = __this_cpu_read(ksoftirqd);
 
+       if (pending & SOFTIRQ_NOW_MASK)
+               return false;
        return tsk && (tsk->state == TASK_RUNNING);
 }
 
@@ -139,9 +143,13 @@ static void __local_bh_enable(unsigned int cnt)
 {
        lockdep_assert_irqs_disabled();
 
+       if (preempt_count() == cnt)
+               trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
+
        if (softirq_count() == (cnt & SOFTIRQ_MASK))
                trace_softirqs_on(_RET_IP_);
-       preempt_count_sub(cnt);
+
+       __preempt_count_sub(cnt);
 }
 
 /*
@@ -325,7 +333,7 @@ asmlinkage __visible void do_softirq(void)
 
        pending = local_softirq_pending();
 
-       if (pending && !ksoftirqd_running())
+       if (pending && !ksoftirqd_running(pending))
                do_softirq_own_stack();
 
        local_irq_restore(flags);
@@ -352,7 +360,7 @@ void irq_enter(void)
 
 static inline void invoke_softirq(void)
 {
-       if (ksoftirqd_running())
+       if (ksoftirqd_running(local_softirq_pending()))
                return;
 
        if (!force_irqthreads) {
@@ -383,7 +391,7 @@ static inline void tick_irq_exit(void)
 
        /* Make sure that timer wheel updates are propagated */
        if ((idle_cpu(cpu) && !need_resched()) || tick_nohz_full_cpu(cpu)) {
-               if (!in_interrupt())
+               if (!in_irq())
                        tick_nohz_irq_exit();
        }
 #endif