diff mbox series

eal: avoid issues in macro expansion of alignment

Message ID 20230703185551.57908-1-stephen@networkplumber.org (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series eal: avoid issues in macro expansion of alignment |

Checks

Context Check Description
ci/checkpatch warning coding style issues
ci/loongarch-compilation success Compilation OK
ci/loongarch-unit-testing success Unit Testing PASS
ci/Intel-compilation success Compilation OK
ci/intel-Testing success Testing PASS
ci/github-robot: build success github build: passed
ci/intel-Functional success Functional PASS
ci/iol-mellanox-Performance success Performance Testing PASS
ci/iol-abi-testing success Testing PASS
ci/iol-unit-testing success Testing PASS
ci/iol-aarch-unit-testing success Testing PASS
ci/iol-x86_64-compile-testing success Testing PASS
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-broadcom-Performance success Performance Testing PASS
ci/iol-broadcom-Functional success Functional Testing PASS
ci/iol-aarch64-compile-testing success Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-testing success Testing PASS
ci/iol-x86_64-unit-testing success Testing PASS

Commit Message

Stephen Hemminger July 3, 2023, 6:55 p.m. UTC 
  RTE_ALIGN_MUL_NEAR is a macro so the cycle arguement could
get evaluated twice causing some potential skew.  Fix by
computing value once.

Suggested by patch to fix side effects.

Fixes: 5cbd14b3e5f9 ("eal: roundup TSC frequency when estimating")
Cc: pbhagavatula@marvell.com
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/eal/common/eal_common_timer.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/lib/eal/common/eal_common_timer.c b/lib/eal/common/eal_common_timer.c
index 5686a5102b66..05614b0503cf 100644
--- a/lib/eal/common/eal_common_timer.c
+++ b/lib/eal/common/eal_common_timer.c
@@ -42,10 +42,14 @@  estimate_tsc_freq(void)
 	RTE_LOG(WARNING, EAL, "WARNING: TSC frequency estimated roughly"
 		" - clock timings may be less accurate.\n");
 	/* assume that the rte_delay_us_sleep() will sleep for 1 second */
-	uint64_t start = rte_rdtsc();
+	uint64_t start, elapsed;
+
+	start = rte_rdtsc();
 	rte_delay_us_sleep(US_PER_S);
+	elapsed = rte_rdtsc() - start;
+
 	/* Round up to 10Mhz. 1E7 ~ 10Mhz */
-	return RTE_ALIGN_MUL_NEAR(rte_rdtsc() - start, CYC_PER_10MHZ);
+	return RTE_ALIGN_MUL_NEAR(elapsed, CYC_PER_10MHZ);
 }
 
 void