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Commit b9511cd761 ("perf/x86: Fix time_shift in perf_event_mmap_page")
altered the time conversion algorithms documented in the perf_event.h
header file, to use 64-bit shifts. That was done to make the code more
future-proof (i.e. some time in the future a 32-bit shift could be
allowed). Reflect those changes in perf tools.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1457005856-6143-9-git-send-email-adrian.hunter@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
31 lines
620 B
C
31 lines
620 B
C
#include <linux/compiler.h>
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#include <linux/types.h>
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#include "tsc.h"
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u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc)
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{
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u64 t, quot, rem;
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t = ns - tc->time_zero;
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quot = t / tc->time_mult;
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rem = t % tc->time_mult;
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return (quot << tc->time_shift) +
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(rem << tc->time_shift) / tc->time_mult;
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}
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u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc)
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{
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u64 quot, rem;
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quot = cyc >> tc->time_shift;
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rem = cyc & (((u64)1 << tc->time_shift) - 1);
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return tc->time_zero + quot * tc->time_mult +
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((rem * tc->time_mult) >> tc->time_shift);
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}
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u64 __weak rdtsc(void)
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{
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return 0;
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}
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