[RFC] RISC-V:[gprofng] Mimal support gprofng for riscv

Message ID 20240628102826.4846-1-466530436@qq.com
State New
Headers
Series [RFC] RISC-V:[gprofng] Mimal support gprofng for riscv |

Checks

Context Check Description
linaro-tcwg-bot/tcwg_binutils_build--master-aarch64 fail Patch failed to apply
linaro-tcwg-bot/tcwg_binutils_build--master-arm fail Patch failed to apply

Commit Message

XYenChi June 28, 2024, 10:28 a.m. UTC
  From: XYenChi <oriachiuan@gmail.com>

Minimal support RISC-V. Test with qemu.

Result show:
[xyenchi@qemu-riscv build]$ ./gprofng/src/gp-display-text -fu1.er/p -head test.2.er/
Functions sorted by metric: Exclusive Total CPU Time

Excl. Total   Incl. Total    Name
CPU           CPU
 sec.      %   sec.      %
0.      0.    0.      0.     <Total>

ID Sel    PID Experiment
== === ====== ==========
 1 yes 145674 test.1.er/
Experiment: test.1.er/
No errors
No warnings
No archive command run

Target command (64-bit): 'echo 1'
Process pid 145674, ppid 399, pgrp 145674, sid 392
Current working directory: /home/xyenchi/binutils-gdb/build
Collector version: `2.41.50'; experiment version 12.4 (64-bit)
Host `qemu-riscv', OS `Linux 6.7.0-rc8', page size 4096, architecture `riscv64'
  0 CPUs, clock speed 0 MHz.
  Memory: 4096267 pages @  4096 = 16001 MB.
Data collection parameters:
  Clock-profiling, interval = 10007 microsecs.
  Periodic sampling, 1 secs.
  Follow descendant processes from: fork|exec|combo

Experiment started Thu Jun 27 16:23:20 2024

Experiment Ended: 0.040909200
Data Collection Duration: 0.040909200

If build with `allow_undefined_flag=true`, result will be:

[xyenchi@qemu-riscv build]$ ./gprofng/src/gp-display-text -fu1.er/p -head test.2.er/
Functions sorted by metric: Exclusive Total CPU Time

Excl. Total   Incl. Total    Name
CPU           CPU
 sec.      %   sec.      %
0.      0.    0.      0.     <Total>

ID Sel    PID Experiment
== === ====== ==========
 1 yes 145674 test.1.er/
Experiment: test.1.er/
No errors
No warnings
No archive command run

Target command (64-bit): 'echo 1'
Process pid 145674, ppid 399, pgrp 145674, sid 392
Current working directory: /home/xyenchi/binutils-gdb/build
Collector version: `2.41.50'; experiment version 12.4 (64-bit)
Host `qemu-riscv', OS `Linux 6.7.0-rc8', page size 4096, architecture `riscv64'
  0 CPUs, clock speed 0 MHz.
  Memory: 4096267 pages @  4096 = 16001 MB.
Data collection parameters:
  Clock-profiling, interval = 10007 microsecs.
  Periodic sampling, 1 secs.
  Follow descendant processes from: fork|exec|combo

Experiment started Thu Jun 27 16:23:20 2024

Experiment Ended: 0.040909200
Data Collection Duration: 0.040909200

ChangeLog:
  Minimal support gprofng for RISC-V.

2024-06-28  Yixuan Chen  <chenyixuan@iscasc.ac.cn>

        * configure: Add RISC-V configure.
        * configure.ac: Add RISC-V configure.

Unknown ChangeLog:

2024-06-28  Yixuan Chen  <chenyixuan@iscasc.ac.cn>

        * gprofng/common/core_pcbe.c (core_pcbe_init): Add RISC-V vendor.
        (defined): Add RISC-V condition.
        * gprofng/common/cpuid.c (defined): Add head file to use hwprobe.
        (my_cpuid): Add riscv hwprobe.
        * gprofng/common/gp-defs.h (TOK_A_RISCV): Add RISC-V.
        (defined): Add RISC-V.
        (ARCH_RISCV): Add RISC-V.
        * gprofng/common/hwc_cpus.h: Add RISC-V vendor id.
        * gprofng/common/hwcfuncs.h (HW_INTERVAL_TYPE): fix typo.
        * gprofng/configure: Add RISC-V.
        * gprofng/configure.ac: Add RISC-V.
        * gprofng/libcollector/hwprofile.h (ARCH): Add riscv register calling.
        (CONTEXT_PC): Add riscv register calling.
        (CONTEXT_FP): Add riscv register calling.
        (CONTEXT_SP): Add riscv register calling.
        (SETFUNCTIONCONTEXT): Add riscv uc_mcontext calling.
        * gprofng/libcollector/libcol_util.c (__collector_util_init): fix libc calling
        * gprofng/libcollector/libcol_util.h (__collector_cas_32): Add RISC-V.
        (ARCH):
        * gprofng/libcollector/unwind.c (ARCH): Add RISC-V.
        (GET_PC): Add riscv register calling.
        (GET_SP): Add riscv register calling.
        (GET_FP): Add riscv register calling.
        (FILL_CONTEXT): Add riscv uc_mcontext calling.
        * gprofng/src/DbeSession.cc (ARCH):
        * gprofng/src/Disasm.cc (Disasm::disasm_open): Add RISC-V.
        * gprofng/src/Experiment.cc (Experiment::ExperimentHandler::startElement): Add RISC-V.
        * gprofng/src/checks.cc (ARCH): Add RISC-V.
        * gprofng/src/collctrl.cc (_SC_CPUID_MAX): Add if not define _SC_CPUID_MAX condition. Set CPU frequency as 1000 to test but now not show at the test result, will fix with better way to get cpu frequency.
        (Coll_Ctrl::Coll_Ctrl):
        (defined):
        * gprofng/src/dbe_types.h (enum Platform_t):Add RISC-V.
        * gprofng/testsuite/gprofng.display/mttest/gethrtime.c: Add RISC-V.

---
 configure                                     |  2 +-
 configure.ac                                  |  2 +-
 gprofng/common/core_pcbe.c                    |  5 ++-
 gprofng/common/cpuid.c                        | 31 +++++++++++++++++--
 gprofng/common/gp-defs.h                      |  5 ++-
 gprofng/common/hwc_cpus.h                     |  7 +++++
 gprofng/common/hwcfuncs.h                     |  2 +-
 gprofng/configure                             |  4 +++
 gprofng/configure.ac                          |  4 +++
 gprofng/libcollector/hwprofile.h              | 10 ++++++
 gprofng/libcollector/libcol_util.c            | 11 ++++++-
 gprofng/libcollector/libcol_util.h            | 10 +++---
 gprofng/libcollector/unwind.c                 | 16 ++++++++--
 gprofng/src/DbeSession.cc                     |  2 ++
 gprofng/src/Disasm.cc                         |  2 ++
 gprofng/src/Experiment.cc                     |  2 ++
 gprofng/src/checks.cc                         |  4 +++
 gprofng/src/collctrl.cc                       | 26 +++++++++-------
 gprofng/src/dbe_types.h                       |  3 +-
 .../gprofng.display/mttest/gethrtime.c        |  2 ++
 20 files changed, 123 insertions(+), 27 deletions(-)
  

Patch

diff --git a/configure b/configure
index dd743c58663..e3cbad5752b 100755
--- a/configure
+++ b/configure
@@ -3145,7 +3145,7 @@  fi
 
 if test "$enable_gprofng" = "yes"; then
   case "${target}" in
-    x86_64-*-linux* | i?86-*-linux* | aarch64-*-linux*)
+    x86_64-*-linux* | i?86-*-linux* | aarch64-*-linux* | riscv64-*-linux*)
     configdirs="$configdirs gprofng"
     ;;
   esac
diff --git a/configure.ac b/configure.ac
index 01cfd017273..e63f27e6a29 100644
--- a/configure.ac
+++ b/configure.ac
@@ -412,7 +412,7 @@  enable_gprofng=$enableval,
 enable_gprofng=yes)
 if test "$enable_gprofng" = "yes"; then
   case "${target}" in
-    x86_64-*-linux* | i?86-*-linux* | aarch64-*-linux*)
+    x86_64-*-linux* | i?86-*-linux* | aarch64-*-linux* | riscv64-*-linux*)
     configdirs="$configdirs gprofng"
     ;;
   esac
diff --git a/gprofng/common/core_pcbe.c b/gprofng/common/core_pcbe.c
index b71d46f4e31..ef2a3f83d42 100644
--- a/gprofng/common/core_pcbe.c
+++ b/gprofng/common/core_pcbe.c
@@ -2754,6 +2754,9 @@  core_pcbe_init (void)
       return 0;
     case X86_VENDOR_Intel:
       break;
+	case ANDES_VENDOR_ID:
+    case SIFIVE_VENDOR_ID:
+    case THEAD_VENDOR_ID:
     default:
       return -1;
     }
@@ -2915,7 +2918,7 @@  core_pcbe_impl_name (void)
 static const char *
 core_pcbe_cpuref (void)
 {
-#if defined(__aarch64__)
+#if defined(__aarch64__) || defined(__riscv)
   return "";
 #elif defined(__i386__) || defined(__x86_64)
   switch (cpuid_getmodel ())
diff --git a/gprofng/common/cpuid.c b/gprofng/common/cpuid.c
index fd98b30c639..c29b6612afe 100644
--- a/gprofng/common/cpuid.c
+++ b/gprofng/common/cpuid.c
@@ -42,6 +42,11 @@  __get_cpuid (unsigned int op ATTRIBUTE_UNUSED, unsigned int *eax,
   Tprintf (DBG_LT0, "cpuid.c:%d read_cpuid_id() MIDR_EL1=0x%016x\n", __LINE__, *eax);
   return res;
 }
+#elif defined(__riscv)
+#include <sched.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <asm/hwprobe.h>
 #endif
 
 /*
@@ -104,7 +109,7 @@  my_cpuid (unsigned int op, cpuid_regs_t *regs)
   TprintfT (DBG_LT1, "my_cpuid: __get_cpuid(0x%x, 0x%x, 0x%x, 0x%x, 0x%x) returns %d\n",
 	    op, regs->eax, regs->ebx, regs->ecx, regs->edx, ret);
   return ret;
-}
+} 
 #endif
 
 static cpuid_info_t *
@@ -180,8 +185,30 @@  get_cpuid_info ()
 	cpi->cpi_model += CPI_MODEL_XTD (regs.eax) << 4;
       break;
     }
+#elif defined(__riscv)
+  #ifndef __riscv_hwprobe
+	  cpi->cpi_vendor = 0;
+	  cpi->cpi_family = 0;
+	  cpi->cpi_model = 0;
+  #else
+		struct riscv_hwprobe res;
+	  	res.key = RISCV_HWPROBE_KEY_MVENDORID;
+	  	cpu_set_t cpu_set;
+	        int __riscv_hwprobe (struct riscv_hwprobe *pairs, 			\
+					long pair_count, long cpu_count, 		\
+					unsigned long *cpus, unsigned long flags)	\
+          {
+                return syscall(__NR_riscv_hwprobe, pairs, pair_count, cpu_count, cpus, flags);
+          }
+          CPU_ZERO(&cpu_set);
+          CPU_SET(0, &cpu_set);
+          long ret = __riscv_hwprobe(&res, 1, 1, &cpu_set, 0);
+	  cpi->cpi_vendor = res.value;
+	  cpi->cpi_family = 0;
+	  cpi->cpi_model = 0;
+	#endif
 #endif
-  return cpi;
+    return cpi;
 }
 
 static inline uint_t
diff --git a/gprofng/common/gp-defs.h b/gprofng/common/gp-defs.h
index 7cef5550696..891c4d32cf1 100644
--- a/gprofng/common/gp-defs.h
+++ b/gprofng/common/gp-defs.h
@@ -32,6 +32,7 @@ 
  */
 #define ARCH(x)             TOK_A_##x(ARCH)
 #define TOK_A_Aarch64(x)    x##_Aarch64
+#define TOK_A_RISCV(x)      x##_RISCV
 #define TOK_A_SPARC(x)      x##_SPARC
 #define TOK_A_Intel(x)      x##_Intel
 
@@ -45,11 +46,13 @@ 
 #define ARCH_Intel          1
 #elif defined(__aarch64__)
 #define ARCH_Aarch64        1
+#elif defined(riscv) || defined(__riscv)
+#define ARCH_RISCV          1
 #else
 #error "Undefined platform"
 #endif
 
-#if defined(__sparcv9) || defined(__x86_64) || defined(__aarch64__)
+#if defined(__sparcv9) || defined(__x86_64) || defined(__aarch64__) || defined(__riscv)
 #define WSIZE_64            1
 #else
 #define WSIZE_32            1
diff --git a/gprofng/common/hwc_cpus.h b/gprofng/common/hwc_cpus.h
index be820819dd3..b121e4bfb97 100644
--- a/gprofng/common/hwc_cpus.h
+++ b/gprofng/common/hwc_cpus.h
@@ -111,6 +111,13 @@  enum {
     ARM_CPU_IMP_QCOM    = 0x51
 };
 
+// rscv Constants from arch/riscv/include/asm/vendorid_list.h
+enum {
+	ANDES_VENDOR_ID		=0x31e,
+	SIFIVE_VENDOR_ID	=0x489,
+	THEAD_VENDOR_ID		=0x5b7
+};
+
 #define	AARCH64_VENDORSTR_ARM	"ARM"
 
   /* strings below must match those returned by cpc_getcpuver() */
diff --git a/gprofng/common/hwcfuncs.h b/gprofng/common/hwcfuncs.h
index a5f64f2a33f..1a6ee7e30ca 100644
--- a/gprofng/common/hwcfuncs.h
+++ b/gprofng/common/hwcfuncs.h
@@ -98,7 +98,7 @@  typedef struct {                                /* supplementary data fields */
 
 #define HW_INTERVAL_MAX         UINT64_MAX
 #define HW_INTERVAL_PRESET(x)   (HW_INTERVAL_MAX - ((uint64_t)(x) - 1))
-#define HW_INTERVAL_TYPE(x)     ((uint64_t) (x)
+#define HW_INTERVAL_TYPE(x)     ((uint64_t) (x))
 
 /* parsing */
 #define HWCFUNCS_MAX_ATTRS              20
diff --git a/gprofng/configure b/gprofng/configure
index 1c6a99291be..9ac7a651809 100755
--- a/gprofng/configure
+++ b/gprofng/configure
@@ -15788,6 +15788,10 @@  build_src=
       build_src=true
       build_collector=true
       ;;
+    riscv*-*-linux*)
+      build_src=true
+      build_collector=true
+      ;;
   esac
   # Check whether --enable-gprofng-tools was given.
 if test "${enable_gprofng_tools+set}" = set; then :
diff --git a/gprofng/configure.ac b/gprofng/configure.ac
index 6b8fe262748..b4f2981a487 100644
--- a/gprofng/configure.ac
+++ b/gprofng/configure.ac
@@ -63,6 +63,10 @@  build_src=
       build_src=true
       build_collector=true
       ;;
+    riscv*-*-linux*)
+      build_src=true
+      build_collector=true
+      ;;
   esac
   AC_ARG_ENABLE(gprofng-tools,
     AS_HELP_STRING([--disable-gprofng-tools], [do not build gprofng/src directory]),
diff --git a/gprofng/libcollector/hwprofile.h b/gprofng/libcollector/hwprofile.h
index 23422dd51fa..6517452eef7 100644
--- a/gprofng/libcollector/hwprofile.h
+++ b/gprofng/libcollector/hwprofile.h
@@ -84,6 +84,16 @@  typedef struct MHwcntr_packet
     (ucp)->uc_mcontext.regs[CONTEXT_PC] = (greg_t)(funcp); \
     (ucp)->uc_mcontext.regs[CONTEXT_SP] = 0; \
     (ucp)->uc_mcontext.regs[CONTEXT_FP] = 0;
+
+#elif ARCH(RISCV)
+#define CONTEXT_PC REG_PC
+#define CONTEXT_FP 8
+#define CONTEXT_SP 2
+#define SETFUNCTIONCONTEXT(ucp,funcp) \
+    (ucp)->uc_mcontext.__gregs[CONTEXT_PC] = (greg_t)(funcp); \
+    (ucp)->uc_mcontext.__gregs[CONTEXT_FP] = 0; \
+    (ucp)->uc_mcontext.__gregs[CONTEXT_SP] = 0;
+     
 #endif /* ARCH() */
 
 #endif
diff --git a/gprofng/libcollector/libcol_util.c b/gprofng/libcollector/libcol_util.c
index a8802d4a9b0..8ee1c56ff45 100644
--- a/gprofng/libcollector/libcol_util.c
+++ b/gprofng/libcollector/libcol_util.c
@@ -91,7 +91,7 @@  __collector_gettid ()
 #endif
   __asm__ __volatile__(syscall_instr
 		       : "=a" (r) : "0" (__NR_gettid)
-		       : syscall_clobber);
+		       : syscall_clobber);   
 #else
   r = syscall (__NR_gettid);
 #endif
@@ -1459,7 +1459,10 @@  __collector_util_init ()
   else if ((ptr = dlvsym (libc, "fopen", "GLIBC_2.0")) != NULL)
     __collector_util_funcs.fopen = ptr;
   else
+  {
     ptr = dlsym (libc, "fopen");
+    if(ptr) __collector_util_funcs.fopen = ptr;
+  }
   if (__collector_util_funcs.fopen == NULL)
     {
       CALL_UTIL (fprintf)(stderr, "COL_ERROR_UTIL_INIT fopen: %s\n", dlerror ());
@@ -1475,7 +1478,10 @@  __collector_util_init ()
   else if ((ptr = dlvsym (libc, "popen", "GLIBC_2.0")) != NULL)
     __collector_util_funcs.popen = ptr;
   else
+  {
     ptr = dlsym (libc, "popen");
+    if(ptr) __collector_util_funcs.popen = ptr;
+  }
   if (__collector_util_funcs.popen == NULL)
     {
       CALL_UTIL (fprintf)(stderr, "COL_ERROR_UTIL_INIT popen: %s\n", dlerror ());
@@ -1491,7 +1497,10 @@  __collector_util_init ()
   else if ((ptr = dlvsym (libc, "fclose", "GLIBC_2.0")) != NULL)
     __collector_util_funcs.fclose = ptr;
   else
+  {
     ptr = dlsym (libc, "fclose");
+    if(ptr) __collector_util_funcs.fclose = ptr;
+  }
   if (__collector_util_funcs.fclose == NULL)
     {
       CALL_UTIL (fprintf)(stderr, "COL_ERROR_UTIL_INIT fclose: %s\n", dlerror ());
diff --git a/gprofng/libcollector/libcol_util.h b/gprofng/libcollector/libcol_util.h
index c21b4a46c4b..6ac84db05ab 100644
--- a/gprofng/libcollector/libcol_util.h
+++ b/gprofng/libcollector/libcol_util.h
@@ -209,10 +209,10 @@  static __attribute__ ((always_inline)) inline uint32_t
 __collector_cas_32 (volatile uint32_t *pdata, uint32_t old, uint32_t new)
 {
   uint32_t r;
-  __asm__ __volatile__("lock; cmpxchgl %2, %1"
-		       : "=a" (r), "=m" (*pdata) : "r" (new),
-		       "a" (old), "m" (*pdata));
-  return r;
+	__asm__ __volatile__("lock; cmpxchgl %2, %1"
+			: "=a" (r), "=m" (*pdata) : "r" (new),
+			"a" (old), "m" (*pdata));
+	return r;
 }
 /**
  * This function enables a compare and swap operation to occur atomically.
@@ -270,7 +270,7 @@  __collector_cas_ptr (void *mem, void *cmp, void *new)
   return r;
 }
 
-#elif ARCH(Aarch64)
+#elif ARCH(Aarch64) || ARCH(RISCV)
 static __attribute__ ((always_inline)) inline uint32_t
 __collector_inc_32 (volatile uint32_t *ptr)
 {
diff --git a/gprofng/libcollector/unwind.c b/gprofng/libcollector/unwind.c
index ff2f7aa9a7e..1244a453457 100644
--- a/gprofng/libcollector/unwind.c
+++ b/gprofng/libcollector/unwind.c
@@ -186,8 +186,14 @@  memory_error_func (int status ATTRIBUTE_UNUSED, bfd_vma addr ATTRIBUTE_UNUSED,
 #define GET_PC(ctx) (((ucontext_t*)ctx)->uc_mcontext.regs[15])
 #define GET_SP(ctx) (((ucontext_t*)ctx)->uc_mcontext.regs[13])
 #define GET_FP(ctx) (((ucontext_t*)ctx)->uc_mcontext.regs[14])
+
+#elif ARCH(RISCV)
+#define GET_PC(ctx) (((ucontext_t*)ctx)->uc_mcontext.__gregs[REG_PC])
+#define GET_SP(ctx) (((ucontext_t*)ctx)->uc_mcontext.__gregs[2])
+#define GET_FP(ctx) (((ucontext_t*)ctx)->uc_mcontext.__gregs[8])
 #endif /* ARCH() */
 
+
 /*
  * FILL_CONTEXT() for all platforms
  * Could use getcontext() except:
@@ -230,13 +236,19 @@  memory_error_func (int status ATTRIBUTE_UNUSED, bfd_vma addr ATTRIBUTE_UNUSED,
 	    context->uc_stack.ss_size = 0x100000; \
 	}
 
-#elif ARCH(Aarch64)
+#elif ARCH(Aarch64) 
 #define FILL_CONTEXT(context) \
     { CALL_UTIL (getcontext) (context);  \
       context->uc_mcontext.sp = (__u64) __builtin_frame_address(0); \
     }
 
-#endif /* ARCH() */
+#elif ARCH(RISCV)
+#define FILL_CONTEXT(context) \
+	{ CALL_UTIL(getcontext)(context);  \
+	  context->uc_mcontext.__gregs[2] = (uint64_t) __builtin_frame_address(0); \	
+	}
+
+#endif/* ARCH() */
 
 static int
 getByteInstruction (unsigned char *p)
diff --git a/gprofng/src/DbeSession.cc b/gprofng/src/DbeSession.cc
index 86541d97f2e..3c218b5fc91 100644
--- a/gprofng/src/DbeSession.cc
+++ b/gprofng/src/DbeSession.cc
@@ -94,6 +94,8 @@  Platform_t DbeSession::platform =
 	Sparc;
 #elif ARCH(Aarch64)
 	Aarch64;
+#elif ARCH(RISCV)
+  RISCV;
 #else   // ARCH(Intel)
 	Intel;
 #endif
diff --git a/gprofng/src/Disasm.cc b/gprofng/src/Disasm.cc
index 9c7e59a590b..19e6f15ff6f 100644
--- a/gprofng/src/Disasm.cc
+++ b/gprofng/src/Disasm.cc
@@ -208,6 +208,7 @@  Disasm::disasm_open ()
     case Amd64:
       need_swap_endian = (DbeSession::platform == Sparc);
       break;
+    case RISCV:
     case Sparcv8plus:
     case Sparcv9:
     case Sparc:
@@ -246,6 +247,7 @@  Disasm::disasm_open ()
       dis_info.arch = bfd_arch_i386;
       dis_info.mach = bfd_mach_x86_64;
       break;
+    case RISCV:
     case Sparcv8plus:
     case Sparcv9:
     case Sparc:
diff --git a/gprofng/src/Experiment.cc b/gprofng/src/Experiment.cc
index 1378ad5ce07..ac78276d23c 100644
--- a/gprofng/src/Experiment.cc
+++ b/gprofng/src/Experiment.cc
@@ -542,6 +542,8 @@  Experiment::ExperimentHandler::startElement (char*, char*, char *qName, Attribut
 	    exp->platform = Intel;
 	  else if (strcmp (str, "aarch64") == 0)
 	    exp->platform = Aarch64;
+    else if (strcmp (str, "riscv64") == 0)
+      exp->platform = RISCV;
 	  else
 	    exp->platform = Sparc;
 	  exp->need_swap_endian = (DbeSession::platform == Sparc) ?
diff --git a/gprofng/src/checks.cc b/gprofng/src/checks.cc
index 094c3bbc60a..2f9fbd7f714 100644
--- a/gprofng/src/checks.cc
+++ b/gprofng/src/checks.cc
@@ -332,6 +332,10 @@  collect::check_executable_arch (Elf *elf)
     case EM_AARCH64:
       is_64 = true;
       break;
+#elif ARCH(RISCV)
+	case EM_RISCV:
+	  is_64 = true;
+	  break;
 #endif
     default:
       return EXEC_ELF_ARCH;
diff --git a/gprofng/src/collctrl.cc b/gprofng/src/collctrl.cc
index 5d68b689a64..1b04e52b5cc 100644
--- a/gprofng/src/collctrl.cc
+++ b/gprofng/src/collctrl.cc
@@ -51,9 +51,9 @@  extern const char *strsignal (int);
 #endif
 
 // _SC_CPUID_MAX is not available on 2.6/2.7
-#ifndef _SC_CPUID_MAX
-#define _SC_CPUID_MAX       517
-#endif
+
+// #define _SC_CPUID_MAX       517
+// #endif
 
 const char *get_fstype (char *);
 
@@ -74,15 +74,16 @@  Coll_Ctrl::Coll_Ctrl (int _interactive, bool _defHWC, bool _kernelHWC)
   default_stem = strdup ("test");
 
   /* get CPU count and processor clock rate */
+  #ifndef _SC_CPUID_MAX
+  ncpus = sysconf (_SC_NPROCESSORS_CONF);
+  /* add 2048 to count, since on some systems CPUID does not start at zero */
+  ncpumax = ncpus + 2048;
+  #elif
   ncpumax = sysconf (_SC_CPUID_MAX);
-  if (ncpumax == -1)
-    {
-      ncpus = sysconf (_SC_NPROCESSORS_CONF);
-      /* add 2048 to count, since on some systems CPUID does not start at zero */
-      ncpumax = ncpus + 2048;
-    }
-  ncpus = 0;
-  cpu_clk_freq = 0;
+  #endif
+
+  //ncpus = 0;
+  //cpu_clk_freq = 0;
 
   // On Linux, read /proc/cpuinfo to get CPU count and clock rate
   // Note that parsing is different on SPARC and x86
@@ -115,6 +116,9 @@  Coll_Ctrl::Coll_Ctrl (int _interactive, bool _defHWC, bool _kernelHWC)
 #elif defined(__aarch64__)
   asm volatile("mrs %0, cntfrq_el0" : "=r" (cpu_clk_freq));
 
+#elif defined(__riscv)
+	cpu_clk_freq = 1000;
+
 #else
   FILE *procf = fopen ("/proc/cpuinfo", "r");
   if (procf != NULL)
diff --git a/gprofng/src/dbe_types.h b/gprofng/src/dbe_types.h
index 9fa842ce85d..c67d421566e 100644
--- a/gprofng/src/dbe_types.h
+++ b/gprofng/src/dbe_types.h
@@ -42,7 +42,8 @@  enum Platform_t
   Sparcv8plus,
   Java,
   Amd64,
-  Aarch64
+  Aarch64,
+  RISCV
 };
 
 enum WSize_t
diff --git a/gprofng/testsuite/gprofng.display/mttest/gethrtime.c b/gprofng/testsuite/gprofng.display/mttest/gethrtime.c
index da39821027f..5e2cc3dc97b 100644
--- a/gprofng/testsuite/gprofng.display/mttest/gethrtime.c
+++ b/gprofng/testsuite/gprofng.display/mttest/gethrtime.c
@@ -32,6 +32,8 @@ 
 #define SPARC       1
 #elif defined(__aarch64__)
 #define Aarch64     1
+#elif defined(__riscv)
+#define RISCV       1
 #else
 #define Intel       1
 #endif