From: Douglas Anderson <diand...@chromium.org> The printouts writen to the logs by suspend can be a bit opaque: it can be hard to track them down to the actual function called. You might see:
calling rfkill1+ @ 19473, parent: phy0 call rfkill1+ returned 0 after 1 usecs calling phy0+ @ 19473, parent: mmc2:0001:1 call phy0+ returned 0 after 19 usecs It's a bit hard to know what's actually happening. Instead, it's nice to see: calling rfkill1+ @ 15793, parent: phy0, cb: rfkill_suspend call rfkill1+ returned 0 after 1 usecs calling phy0+ @ 15793, parent: mmc2:0001:1, cb: wiphy_suspend [cfg80211] call phy0+ returned 0 after 7 usecs That makes it very obvious what's going on. It also has the nice side effect of making the suspend/resume spew a little more obvious, since many resume functions have the word "resume" in the name: calling phy0+ @ 15793, parent: mmc2:0001:1, cb: wiphy_resume [cfg80211] call phy0+ returned 0 after 12 usecs calling rfkill1+ @ 15793, parent: phy0, cb: rfkill_resume call rfkill1+ returned 0 after 1 usecs Signed-off-by: Douglas Anderson <diand...@chromium.org> Acked-by: Pavel Machek <pa...@ucw.cz> Signed-off-by: Brian Norris <briannor...@chromium.org> --- This is a resend of the following patch (w/ minor $subject alteration): https://patchwork.kernel.org/patch/7241641/ It was useful for debugging the following patch, so I thought I'd resend. It received an Ack the first time. drivers/base/power/main.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index e44944f4be77..c58563581345 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -190,14 +190,14 @@ void device_pm_move_last(struct device *dev) list_move_tail(&dev->power.entry, &dpm_list); } -static ktime_t initcall_debug_start(struct device *dev) +static ktime_t initcall_debug_start(struct device *dev, void *cb) { ktime_t calltime = ktime_set(0, 0); if (pm_print_times_enabled) { - pr_info("calling %s+ @ %i, parent: %s\n", + pr_info("calling %s+ @ %i, parent: %s, cb: %pf\n", dev_name(dev), task_pid_nr(current), - dev->parent ? dev_name(dev->parent) : "none"); + dev->parent ? dev_name(dev->parent) : "none", cb); calltime = ktime_get(); } @@ -384,7 +384,7 @@ static int dpm_run_callback(pm_callback_t cb, struct device *dev, if (!cb) return 0; - calltime = initcall_debug_start(dev); + calltime = initcall_debug_start(dev, cb); pm_dev_dbg(dev, state, info); trace_device_pm_callback_start(dev, info, state.event); @@ -1330,7 +1330,7 @@ static int legacy_suspend(struct device *dev, pm_message_t state, int error; ktime_t calltime; - calltime = initcall_debug_start(dev); + calltime = initcall_debug_start(dev, cb); trace_device_pm_callback_start(dev, info, state.event); error = cb(dev, state); -- 2.8.0.rc3.226.g39d4020