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@@ -1768,6 +1768,14 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
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* must fill the old tail_page with padding.
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* must fill the old tail_page with padding.
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*/
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*/
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if (tail >= BUF_PAGE_SIZE) {
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if (tail >= BUF_PAGE_SIZE) {
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+ /*
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+ * If the page was filled, then we still need
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+ * to update the real_end. Reset it to zero
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+ * and the reader will ignore it.
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+ */
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+ if (tail == BUF_PAGE_SIZE)
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+ tail_page->real_end = 0;
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+
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local_sub(length, &tail_page->write);
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local_sub(length, &tail_page->write);
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return;
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return;
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}
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}
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@@ -3894,12 +3902,12 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
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ret = read;
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ret = read;
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cpu_buffer->lost_events = 0;
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cpu_buffer->lost_events = 0;
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+
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+ commit = local_read(&bpage->commit);
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/*
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/*
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* Set a flag in the commit field if we lost events
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* Set a flag in the commit field if we lost events
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*/
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*/
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if (missed_events) {
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if (missed_events) {
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- commit = local_read(&bpage->commit);
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-
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/* If there is room at the end of the page to save the
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/* If there is room at the end of the page to save the
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* missed events, then record it there.
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* missed events, then record it there.
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*/
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*/
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@@ -3907,10 +3915,17 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
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memcpy(&bpage->data[commit], &missed_events,
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memcpy(&bpage->data[commit], &missed_events,
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sizeof(missed_events));
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sizeof(missed_events));
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local_add(RB_MISSED_STORED, &bpage->commit);
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local_add(RB_MISSED_STORED, &bpage->commit);
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+ commit += sizeof(missed_events);
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}
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}
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local_add(RB_MISSED_EVENTS, &bpage->commit);
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local_add(RB_MISSED_EVENTS, &bpage->commit);
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}
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}
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+ /*
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+ * This page may be off to user land. Zero it out here.
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+ */
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+ if (commit < BUF_PAGE_SIZE)
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+ memset(&bpage->data[commit], 0, BUF_PAGE_SIZE - commit);
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+
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out_unlock:
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out_unlock:
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spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
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spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
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