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Since gettimeofday will shortly be implemented in terms of clock_gettime on all platforms, internal code should use clock_gettime directly; in addition to removing a layer of indirection, this will allow us to remove the PLT-bypass gunk for gettimeofday. (We can't quite do that yet, but it'll be coming later in this patch series.) In many cases, the changed code does fewer conversions. The changed code always assumes __clock_gettime (CLOCK_REALTIME) cannot fail. Most of the call sites were assuming gettimeofday could not fail, but a few places were checking for errors. POSIX says clock_gettime can only fail if the clock constant is invalid or unsupported, and CLOCK_REALTIME is the one and only clock constant that's required to be supported. For consistency I grepped the entire source tree for any other places that checked for errors from __clock_gettime (CLOCK_REALTIME), found one, and changed it too. (For the record, POSIX also says gettimeofday can never fail.) (It would be nice if we could declare that GNU systems will always support CLOCK_MONOTONIC as well as CLOCK_REALTIME; there are several places where we are using CLOCK_REALTIME where _MONOTONIC would be more appropriate, and/or trying to use _MONOTONIC and then falling back to _REALTIME. But the Hurd doesn't support CLOCK_MONOTONIC yet, and it looks like adding it would involve substantial changes to gnumach's internals and API. Oh well.) A few Hurd-specific files were changed to use __host_get_time instead of __clock_gettime, as this seemed tidier. We also assume this cannot fail. Skimming the code in gnumach leads me to believe the only way it could fail is if __mach_host_self also failed, and our Hurd-specific code consistently assumes that can't happen, so I'm going with that. With the exception of support/support_test_main.c, test cases are not modified, mainly because I didn't want to have to figure out which test cases were testing gettimeofday specifically. The definition of GETTIME in sysdeps/generic/memusage.h had a typo and was not reading tv_sec at all. I fixed this. It appears nobody has been generating malloc traces on a machine that doesn't have a superseding definition. There are a whole bunch of places where the code could be simplified by factoring out timespec subtraction and/or comparison logic, but I want to keep this patch as mechanical as possible. Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu, and aarch64-linux-gnu. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org> Reviewed-by: Lukasz Majewski <lukma@denx.de>
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