hakmem/core/hakmem_trace.h

// hakmem_trace.h - Optional USDT tracepoints for perf (user-space static probes)
// Enable by building with: CFLAGS+=-DHAKMEM_USDT=1 and having <sys/sdt.h> available
// When disabled, all macros compile to no-ops (zero overhead).

#ifndef HAKMEM_TRACE_H
#define HAKMEM_TRACE_H

#if HAKMEM_USDT
#  include <sys/sdt.h>
#  define HAK_TP0(name)                 DTRACE_PROBE(hakmem, name)
#  define HAK_TP1(name,a1)              DTRACE_PROBE1(hakmem, name, (a1))
#  define HAK_TP2(name,a1,a2)           DTRACE_PROBE2(hakmem, name, (a1), (a2))
#  define HAK_TP3(name,a1,a2,a3)        DTRACE_PROBE3(hakmem, name, (a1), (a2), (a3))
#else
#  define HAK_TP0(name)                 do{}while(0)
#  define HAK_TP1(name,a1)              do{ (void)(a1); }while(0)
#  define HAK_TP2(name,a1,a2)           do{ (void)(a1); (void)(a2); }while(0)
#  define HAK_TP3(name,a1,a2,a3)        do{ (void)(a1); (void)(a2); (void)(a3); }while(0)
#endif

// Lightweight printf-free tracing for early-init / SEGV triage.
// Enabled only when built with -DHAKMEM_DEBUG_INIT_TRACE=1.
#ifdef HAKMEM_DEBUG_INIT_TRACE
#  include <unistd.h>
#  include <string.h>
static inline void hak_trace(const char* msg)
{
  if (!msg) return;
  write(2, msg, (size_t)strlen(msg));
}
#  define HAK_TRACE(msg) hak_trace(msg)
#else
#  define HAK_TRACE(msg) ((void)0)
#endif

#endif // HAKMEM_TRACE_H