fixup: use previous bench guard

Author: not-matthias

crates/divan_compat/divan_fork/src/bench/mod.rs

@@ -657,6 +657,8 @@ impl<'a> BenchContext<'a> {
 
         let bench_overheads = timer.bench_overheads();
 
+        #[cfg(unix)]
+        let _guard = codspeed::fifo::BenchGuard::new_with_runner_fifo();
         while {
             // Conditions for when sampling is over:
             if elapsed_picos >= max_picos {
@@ -810,6 +812,8 @@ impl<'a> BenchContext<'a> {
                 elapsed_picos = elapsed_picos.saturating_add(progress_picos);
             }
         }
+        #[cfg(unix)]
+        core::mem::drop(_guard);
 
         // Reset flag for ignoring allocations.
         crate::alloc::IGNORE_ALLOC.set(false);
@@ -909,8 +913,6 @@ impl<'a> BenchContext<'a> {
                     mem::forget(input);
                 }
 
-                #[cfg(unix)]
-                let _guard = codspeed::fifo::BenchGuard::new_with_runner_fifo();
                 sync_threads(true);
                 sample_start = UntaggedTimestamp::start(timer_kind);
 
@@ -933,8 +935,6 @@ impl<'a> BenchContext<'a> {
                 sample_end = UntaggedTimestamp::end(timer_kind);
                 sync_threads(false);
                 save_alloc_info();
-                #[cfg(unix)]
-                core::mem::drop(_guard);
 
                 // Drop outputs and inputs.
                 for _ in 0..sample_size {
@@ -973,8 +973,6 @@ impl<'a> BenchContext<'a> {
                         // reduce benchmarking overhead.
                         let defer_slots_iter = defer_slots_slice.iter();
 
-                        #[cfg(unix)]
-                        let _guard = codspeed::fifo::BenchGuard::new_with_runner_fifo();
                         sync_threads(true);
                         sample_start = UntaggedTimestamp::start(timer_kind);
 
@@ -999,8 +997,6 @@ impl<'a> BenchContext<'a> {
                         sample_end = UntaggedTimestamp::end(timer_kind);
                         sync_threads(false);
                         save_alloc_info();
-                        #[cfg(unix)]
-                        core::mem::drop(_guard);
 
                         // Prevent the optimizer from removing writes to inputs
                         // and outputs in the sample loop.
@@ -1037,8 +1033,6 @@ impl<'a> BenchContext<'a> {
                         // reduce benchmarking overhead.
                         let defer_inputs_iter = defer_inputs_slice.iter();
 
-                        #[cfg(unix)]
-                        let _guard = codspeed::fifo::BenchGuard::new_with_runner_fifo();
                         sync_threads(true);
                         sample_start = UntaggedTimestamp::start(timer_kind);
 
@@ -1059,8 +1053,6 @@ impl<'a> BenchContext<'a> {
                         sample_end = UntaggedTimestamp::end(timer_kind);
                         sync_threads(false);
                         save_alloc_info();
-                        #[cfg(unix)]
-                        core::mem::drop(_guard);
 
                         // Prevent the optimizer from removing writes to inputs
                         // in the sample loop.