From 8622dfefb6ac333c58d354331d1bf78a2927ce51 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Thu, 19 Mar 2020 10:51:52 +0200 Subject: intel_th: msu: Make stopping the trace optional Some use cases prefer to keep collecting the trace data into the last available window while the other windows are being offloaded instead of stopping the trace. In this scenario, the window switch happens automatically when the next window becomes available again. Add an option to allow this and a sysfs attribute to enable it. Signed-off-by: Alexander Shishkin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20200319085152.52183-1-alexander.shishkin@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/intel_th/msu.c | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-) (limited to 'drivers/hwtracing') diff --git a/drivers/hwtracing/intel_th/msu.c b/drivers/hwtracing/intel_th/msu.c index 3cd2489d398c..3a77551fb4fc 100644 --- a/drivers/hwtracing/intel_th/msu.c +++ b/drivers/hwtracing/intel_th/msu.c @@ -138,6 +138,7 @@ struct msc { struct list_head win_list; struct sg_table single_sgt; struct msc_window *cur_win; + struct msc_window *switch_on_unlock; unsigned long nr_pages; unsigned long single_sz; unsigned int single_wrap : 1; @@ -154,6 +155,8 @@ struct msc { struct list_head iter_list; + bool stop_on_full; + /* config */ unsigned int enabled : 1, wrap : 1, @@ -1718,6 +1721,10 @@ void intel_th_msc_window_unlock(struct device *dev, struct sg_table *sgt) return; msc_win_set_lockout(win, WIN_LOCKED, WIN_READY); + if (msc->switch_on_unlock == win) { + msc->switch_on_unlock = NULL; + msc_win_switch(msc); + } } EXPORT_SYMBOL_GPL(intel_th_msc_window_unlock); @@ -1758,7 +1765,11 @@ static irqreturn_t intel_th_msc_interrupt(struct intel_th_device *thdev) /* next window: if READY, proceed, if LOCKED, stop the trace */ if (msc_win_set_lockout(next_win, WIN_READY, WIN_INUSE)) { - schedule_work(&msc->work); + if (msc->stop_on_full) + schedule_work(&msc->work); + else + msc->switch_on_unlock = next_win; + return IRQ_HANDLED; } @@ -2051,11 +2062,36 @@ win_switch_store(struct device *dev, struct device_attribute *attr, static DEVICE_ATTR_WO(win_switch); +static ssize_t stop_on_full_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct msc *msc = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", msc->stop_on_full); +} + +static ssize_t stop_on_full_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct msc *msc = dev_get_drvdata(dev); + int ret; + + ret = kstrtobool(buf, &msc->stop_on_full); + if (ret) + return ret; + + return size; +} + +static DEVICE_ATTR_RW(stop_on_full); + static struct attribute *msc_output_attrs[] = { &dev_attr_wrap.attr, &dev_attr_mode.attr, &dev_attr_nr_pages.attr, &dev_attr_win_switch.attr, + &dev_attr_stop_on_full.attr, NULL, }; -- cgit v1.2.3