From 59c0d31988fb366189502a8ac66b7fe1486b7e40 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 20 Aug 2020 10:11:18 -0700 Subject: [PATCH] selftests: net: tcp_mmap: Use huge pages in receive path One down side of using TCP rx zerocopy is one extra TLB miss per page after the mapping operation. While if the application is using hugepages, the non zerocopy recvmsg() will not have to pay these TLB costs. This patch allows server side to use huge pages for the non zero copy case, to allow fair comparisons when both solutions use optimal conditions. Signed-off-by: Eric Dumazet Cc: Arjun Roy Cc: Soheil Hassas Yeganeh Signed-off-by: David S. Miller --- tools/testing/selftests/net/tcp_mmap.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/net/tcp_mmap.c b/tools/testing/selftests/net/tcp_mmap.c index ca2618f3e7a1..00f837c9bc6c 100644 --- a/tools/testing/selftests/net/tcp_mmap.c +++ b/tools/testing/selftests/net/tcp_mmap.c @@ -157,6 +157,7 @@ void *child_thread(void *arg) void *addr = NULL; double throughput; struct rusage ru; + size_t buffer_sz; int lu, fd; fd = (int)(unsigned long)arg; @@ -164,9 +165,9 @@ void *child_thread(void *arg) gettimeofday(&t0, NULL); fcntl(fd, F_SETFL, O_NDELAY); - buffer = malloc(chunk_size); - if (!buffer) { - perror("malloc"); + buffer = mmap_large_buffer(chunk_size, &buffer_sz); + if (buffer == (void *)-1) { + perror("mmap"); goto error; } if (zflg) { @@ -256,7 +257,7 @@ void *child_thread(void *arg) ru.ru_nvcsw); } error: - free(buffer); + munmap(buffer, buffer_sz); close(fd); if (zflg) munmap(raddr, chunk_size + map_align);