[PATCH v4] PM / suspend: measure the time of filesystem syncing

This patch gives the reader an intuitive metric of the time cost by the kernel issuing a filesystem sync during suspend; although developer can guess by the timestamp of next log or enable the ftrace power event for manual calculation, this manner is easier to read and benefits the automatic script

[PATCH v4] PM / suspend: measure the time of filesystem syncing

This patch gives the reader an intuitive metric of the time cost by the kernel issuing a filesystem sync during suspend; although developer can guess by the timestamp of next log or enable the ftrace power event for manual calculation, this manner is easier to read and benefits the automatic script