https://github.com/google/benchmark/commit/f65741b2bd92461dc2c816056eb9c996ae48ad62
https://github.com/google/benchmark/commit/077db43001b42af3ad23e993b2bdcb4fadb7bcf8
https://github.com/google/benchmark/commit/39be87d3004ff9ff4cdf736651af80c3d15e2497
https://github.com/google/benchmark/commit/c24774dc4f4402c3ad150363321cc972ed2669e7

From f65741b2bd92461dc2c816056eb9c996ae48ad62 Mon Sep 17 00:00:00 2001
From: Helge Deller <deller@gmx.de>
Date: Wed, 8 Jan 2025 13:03:53 +0100
Subject: [PATCH] cycleclock: Support for PA-RISC (hppa) architecture (#1894)

Co-authored-by: dominic <510002+dmah42@users.noreply.github.com>
---
 src/cycleclock.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/cycleclock.h b/src/cycleclock.h
index bd62f5d7e7..7852f3df52 100644
--- a/src/cycleclock.h
+++ b/src/cycleclock.h
@@ -229,6 +229,16 @@ inline BENCHMARK_ALWAYS_INLINE int64_t Now() {
   struct timeval tv;
   gettimeofday(&tv, nullptr);
   return static_cast<int64_t>(tv.tv_sec) * 1000000 + tv.tv_usec;
+#elif defined(__hppa__)
+  // HP PA-RISC provides a user-readable clock counter (cr16), but
+  // it's not syncronized across CPUs and only 32-bit wide when programs
+  // are built as 32-bit binaries.
+  // Use clock_gettime(CLOCK_MONOTONIC, ...) instead of gettimeofday
+  // because is provides nanosecond resolution.
+  // Initialize to always return 0 if clock_gettime fails.
+  struct timespec ts = {0, 0};
+  clock_gettime(CLOCK_MONOTONIC, &ts);
+  return static_cast<int64_t>(ts.tv_sec) * 1000000000 + ts.tv_nsec;
 #else
   // The soft failover to a generic implementation is automatic only for ARM.
   // For other platforms the developer is expected to make an attempt to create

From 077db43001b42af3ad23e993b2bdcb4fadb7bcf8 Mon Sep 17 00:00:00 2001
From: Helge Deller <deller@gmx.de>
Date: Wed, 8 Jan 2025 17:54:08 +0100
Subject: [PATCH] cycleclock: Use cock_gettime() as fallback for any Linux
 architecture (#1899)

The Linux kernel provides the clock_gettime() functions since a long
time already, so it's possible to use it as a generic fallback option
for any architecture if no other (better) possibility has been provided
instead.

I noticed the benchmark package failed to build on debian on the SH-4
architecture, so with this change SH-4 is now the first user of this
fallback option.
---
 src/cycleclock.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/cycleclock.h b/src/cycleclock.h
index 7852f3df5..03e02f805 100644
--- a/src/cycleclock.h
+++ b/src/cycleclock.h
@@ -229,10 +229,12 @@ inline BENCHMARK_ALWAYS_INLINE int64_t Now() {
   struct timeval tv;
   gettimeofday(&tv, nullptr);
   return static_cast<int64_t>(tv.tv_sec) * 1000000 + tv.tv_usec;
-#elif defined(__hppa__)
+#elif defined(__hppa__) || defined(__linux__)
+  // Fallback for all other architectures with a recent Linux kernel, e.g.:
   // HP PA-RISC provides a user-readable clock counter (cr16), but
   // it's not syncronized across CPUs and only 32-bit wide when programs
   // are built as 32-bit binaries.
+  // Same for SH-4 and possibly others.
   // Use clock_gettime(CLOCK_MONOTONIC, ...) instead of gettimeofday
   // because is provides nanosecond resolution.
   // Initialize to always return 0 if clock_gettime fails.
From 39be87d3004ff9ff4cdf736651af80c3d15e2497 Mon Sep 17 00:00:00 2001
From: Helge Deller <deller@gmx.de>
Date: Thu, 9 Jan 2025 11:47:29 +0100
Subject: [PATCH] Fix runtime crash when parsing /proc/cpuinfo fails (#1900)

The testcase fails on sparc64, because the parsing of /proc/cpuinfo
fails and thus currently returns "0" CPUs which finally leads
to division-by-zero faults in the tests.

Fix the issue by returning at least "1" CPU which allows the
tests to run. A error message will be printed in any case.

Long-term the code should be fixed to parse the cpuinfo output
on sparch which looks like this:
...
type            : sun4v
ncpus probed    : 48
ncpus active    : 48
---
 src/sysinfo.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/sysinfo.cc b/src/sysinfo.cc
index 49bff75e5..ce14b8d8e 100644
--- a/src/sysinfo.cc
+++ b/src/sysinfo.cc
@@ -561,10 +561,12 @@ int GetNumCPUsImpl() {
 }
 
 int GetNumCPUs() {
-  const int num_cpus = GetNumCPUsImpl();
+  int num_cpus = GetNumCPUsImpl();
   if (num_cpus < 1) {
     std::cerr << "Unable to extract number of CPUs.  If your platform uses "
                  "/proc/cpuinfo, custom support may need to be added.\n";
+    /* There is at least one CPU which we run on. */
+    num_cpus = 1;
   }
   return num_cpus;
 }
From c24774dc4f4402c3ad150363321cc972ed2669e7 Mon Sep 17 00:00:00 2001
From: Helge Deller <deller@gmx.de>
Date: Thu, 9 Jan 2025 17:07:43 +0100
Subject: [PATCH] Get number of CPUs with sysconf() on Linux (#1901)

* Get number of CPUs with sysconf() on Linux

Avoid parsing the /proc/cpuinfo just to get number of CPUs.
Instead use the portable function provided by glibc.

* Update sysinfo.cc
---
 src/sysinfo.cc | 54 +++-----------------------------------------------
 1 file changed, 3 insertions(+), 51 deletions(-)

diff --git a/src/sysinfo.cc b/src/sysinfo.cc
index ce14b8d8e..eddd430e6 100644
--- a/src/sysinfo.cc
+++ b/src/sysinfo.cc
@@ -492,14 +492,14 @@ int GetNumCPUsImpl() {
   GetSystemInfo(&sysinfo);
   // number of logical processors in the current group
   return static_cast<int>(sysinfo.dwNumberOfProcessors);
-#elif defined(BENCHMARK_OS_SOLARIS)
+#elif defined(__linux__) || defined(BENCHMARK_OS_SOLARIS)
   // Returns -1 in case of a failure.
-  long num_cpu = sysconf(_SC_NPROCESSORS_ONLN);
+  int num_cpu = static_cast<int>(sysconf(_SC_NPROCESSORS_ONLN));
   if (num_cpu < 0) {
     PrintErrorAndDie("sysconf(_SC_NPROCESSORS_ONLN) failed with error: ",
                      strerror(errno));
   }
-  return (int)num_cpu;
+  return num_cpu;
 #elif defined(BENCHMARK_OS_QNX)
   return static_cast<int>(_syspage_ptr->num_cpu);
 #elif defined(BENCHMARK_OS_QURT)
@@ -508,54 +508,6 @@ int GetNumCPUsImpl() {
     hardware_threads.max_hthreads = 1;
   }
   return hardware_threads.max_hthreads;
-#else
-  int num_cpus = 0;
-  int max_id = -1;
-  std::ifstream f("/proc/cpuinfo");
-  if (!f.is_open()) {
-    std::cerr << "Failed to open /proc/cpuinfo\n";
-    return -1;
-  }
-#if defined(__alpha__)
-  const std::string Key = "cpus detected";
-#else
-  const std::string Key = "processor";
-#endif
-  std::string ln;
-  while (std::getline(f, ln)) {
-    if (ln.empty()) continue;
-    std::size_t split_idx = ln.find(':');
-    std::string value;
-#if defined(__s390__)
-    // s390 has another format in /proc/cpuinfo
-    // it needs to be parsed differently
-    if (split_idx != std::string::npos)
-      value = ln.substr(Key.size() + 1, split_idx - Key.size() - 1);
-#else
-    if (split_idx != std::string::npos) value = ln.substr(split_idx + 1);
-#endif
-    if (ln.size() >= Key.size() && ln.compare(0, Key.size(), Key) == 0) {
-      num_cpus++;
-      if (!value.empty()) {
-        const int cur_id = benchmark::stoi(value);
-        max_id = std::max(cur_id, max_id);
-      }
-    }
-  }
-  if (f.bad()) {
-    PrintErrorAndDie("Failure reading /proc/cpuinfo");
-  }
-  if (!f.eof()) {
-    PrintErrorAndDie("Failed to read to end of /proc/cpuinfo");
-  }
-  f.close();
-
-  if ((max_id + 1) != num_cpus) {
-    fprintf(stderr,
-            "CPU ID assignments in /proc/cpuinfo seem messed up."
-            " This is usually caused by a bad BIOS.\n");
-  }
-  return num_cpus;
 #endif
   BENCHMARK_UNREACHABLE();
 }