From patchwork Fri Oct 14 13:47:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 13007032 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 52FB8C43217 for ; Fri, 14 Oct 2022 13:53:16 +0000 (UTC) Received: from localhost ([::1]:51014 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ojL7j-0008Dr-2W for qemu-devel@archiver.kernel.org; Fri, 14 Oct 2022 09:53:15 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47102) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ojL2P-00053A-64 for qemu-devel@nongnu.org; Fri, 14 Oct 2022 09:47:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:52837) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ojL2M-0001lf-5U for qemu-devel@nongnu.org; Fri, 14 Oct 2022 09:47:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1665755258; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=JmU4qW/qMHX4cizrbM9+JYbp01hAFOZCMtWcHYj6Cu4=; b=AVqmsk02Kj9whjEWyDWFY7jKARXwD0cC9iEc1Pb3F2wcZVnCkP161bv2QuWcOKZqx4Geqq h09rREE8PY11Ks/0pPez/DPr4CvG7upZCuMbsYs5aXUM9BiwwlnYnCpD9LoZRXqbfO7cRD nx7G+AtIVgijzIKHHyD3Ss+RYv8kPcg= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-483-N2ad4LN4O-G-IzdfdkOGhA-1; Fri, 14 Oct 2022 09:47:35 -0400 X-MC-Unique: N2ad4LN4O-G-IzdfdkOGhA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 07849857AAA; Fri, 14 Oct 2022 13:47:35 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.193.239]) by smtp.corp.redhat.com (Postfix) with ESMTP id 06F0E208DDBF; Fri, 14 Oct 2022 13:47:30 +0000 (UTC) From: David Hildenbrand To: qemu-devel@nongnu.org Cc: David Hildenbrand , Michal Privoznik , Igor Mammedov , "Michael S. Tsirkin" , Paolo Bonzini , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , Eduardo Habkost , "Dr . David Alan Gilbert" , Eric Blake , Markus Armbruster , Richard Henderson , Stefan Weil Subject: [PATCH v3 1/7] util: Cleanup and rename os_mem_prealloc() Date: Fri, 14 Oct 2022 15:47:14 +0200 Message-Id: <20221014134720.168738-2-david@redhat.com> In-Reply-To: <20221014134720.168738-1-david@redhat.com> References: <20221014134720.168738-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 Received-SPF: pass client-ip=170.10.129.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Let's * give the function a "qemu_*" style name * make sure the parameters in the implementation match the prototype * rename smp_cpus to max_threads, which makes the semantics of that parameter clearer ... and add a function documentation. Reviewed-by: Michal Privoznik Signed-off-by: David Hildenbrand --- backends/hostmem.c | 6 +++--- hw/virtio/virtio-mem.c | 2 +- include/qemu/osdep.h | 17 +++++++++++++++-- softmmu/cpus.c | 2 +- util/oslib-posix.c | 24 ++++++++++++------------ util/oslib-win32.c | 8 ++++---- 6 files changed, 36 insertions(+), 23 deletions(-) diff --git a/backends/hostmem.c b/backends/hostmem.c index 4428e06738..491cb10b97 100644 --- a/backends/hostmem.c +++ b/backends/hostmem.c @@ -232,7 +232,7 @@ static void host_memory_backend_set_prealloc(Object *obj, bool value, void *ptr = memory_region_get_ram_ptr(&backend->mr); uint64_t sz = memory_region_size(&backend->mr); - os_mem_prealloc(fd, ptr, sz, backend->prealloc_threads, &local_err); + qemu_prealloc_mem(fd, ptr, sz, backend->prealloc_threads, &local_err); if (local_err) { error_propagate(errp, local_err); return; @@ -383,8 +383,8 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp) * specified NUMA policy in place. */ if (backend->prealloc) { - os_mem_prealloc(memory_region_get_fd(&backend->mr), ptr, sz, - backend->prealloc_threads, &local_err); + qemu_prealloc_mem(memory_region_get_fd(&backend->mr), ptr, sz, + backend->prealloc_threads, &local_err); if (local_err) { goto out; } diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c index 30d03e987a..0e9ef4ff19 100644 --- a/hw/virtio/virtio-mem.c +++ b/hw/virtio/virtio-mem.c @@ -467,7 +467,7 @@ static int virtio_mem_set_block_state(VirtIOMEM *vmem, uint64_t start_gpa, int fd = memory_region_get_fd(&vmem->memdev->mr); Error *local_err = NULL; - os_mem_prealloc(fd, area, size, 1, &local_err); + qemu_prealloc_mem(fd, area, size, 1, &local_err); if (local_err) { static bool warned; diff --git a/include/qemu/osdep.h b/include/qemu/osdep.h index b1c161c035..e556e45143 100644 --- a/include/qemu/osdep.h +++ b/include/qemu/osdep.h @@ -568,8 +568,21 @@ unsigned long qemu_getauxval(unsigned long type); void qemu_set_tty_echo(int fd, bool echo); -void os_mem_prealloc(int fd, char *area, size_t sz, int smp_cpus, - Error **errp); +/** + * qemu_prealloc_mem: + * @fd: the fd mapped into the area, -1 for anonymous memory + * @area: start address of the are to preallocate + * @sz: the size of the area to preallocate + * @max_threads: maximum number of threads to use + * @errp: returns an error if this function fails + * + * Preallocate memory (populate/prefault page tables writable) for the virtual + * memory area starting at @area with the size of @sz. After a successful call, + * each page in the area was faulted in writable at least once, for example, + * after allocating file blocks for mapped files. + */ +void qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads, + Error **errp); /** * qemu_get_pid_name: diff --git a/softmmu/cpus.c b/softmmu/cpus.c index 61b27ff59d..01c94fd298 100644 --- a/softmmu/cpus.c +++ b/softmmu/cpus.c @@ -354,7 +354,7 @@ static void qemu_init_sigbus(void) /* * ALERT: when modifying this, take care that SIGBUS forwarding in - * os_mem_prealloc() will continue working as expected. + * qemu_prealloc_mem() will continue working as expected. */ memset(&action, 0, sizeof(action)); action.sa_flags = SA_SIGINFO; diff --git a/util/oslib-posix.c b/util/oslib-posix.c index 827a7aadba..905cbc27cc 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -329,7 +329,7 @@ static void sigbus_handler(int signal) return; } #endif /* CONFIG_LINUX */ - warn_report("os_mem_prealloc: unrelated SIGBUS detected and ignored"); + warn_report("qemu_prealloc_mem: unrelated SIGBUS detected and ignored"); } static void *do_touch_pages(void *arg) @@ -399,13 +399,13 @@ static void *do_madv_populate_write_pages(void *arg) } static inline int get_memset_num_threads(size_t hpagesize, size_t numpages, - int smp_cpus) + int max_threads) { long host_procs = sysconf(_SC_NPROCESSORS_ONLN); int ret = 1; if (host_procs > 0) { - ret = MIN(MIN(host_procs, MAX_MEM_PREALLOC_THREAD_COUNT), smp_cpus); + ret = MIN(MIN(host_procs, MAX_MEM_PREALLOC_THREAD_COUNT), max_threads); } /* Especially with gigantic pages, don't create more threads than pages. */ @@ -418,11 +418,11 @@ static inline int get_memset_num_threads(size_t hpagesize, size_t numpages, } static int touch_all_pages(char *area, size_t hpagesize, size_t numpages, - int smp_cpus, bool use_madv_populate_write) + int max_threads, bool use_madv_populate_write) { static gsize initialized = 0; MemsetContext context = { - .num_threads = get_memset_num_threads(hpagesize, numpages, smp_cpus), + .num_threads = get_memset_num_threads(hpagesize, numpages, max_threads), }; size_t numpages_per_thread, leftover; void *(*touch_fn)(void *); @@ -494,13 +494,13 @@ static bool madv_populate_write_possible(char *area, size_t pagesize) errno != EINVAL; } -void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus, - Error **errp) +void qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads, + Error **errp) { static gsize initialized; int ret; size_t hpagesize = qemu_fd_getpagesize(fd); - size_t numpages = DIV_ROUND_UP(memory, hpagesize); + size_t numpages = DIV_ROUND_UP(sz, hpagesize); bool use_madv_populate_write; struct sigaction act; @@ -530,24 +530,24 @@ void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus, if (ret) { qemu_mutex_unlock(&sigbus_mutex); error_setg_errno(errp, errno, - "os_mem_prealloc: failed to install signal handler"); + "qemu_prealloc_mem: failed to install signal handler"); return; } } /* touch pages simultaneously */ - ret = touch_all_pages(area, hpagesize, numpages, smp_cpus, + ret = touch_all_pages(area, hpagesize, numpages, max_threads, use_madv_populate_write); if (ret) { error_setg_errno(errp, -ret, - "os_mem_prealloc: preallocating memory failed"); + "qemu_prealloc_mem: preallocating memory failed"); } if (!use_madv_populate_write) { ret = sigaction(SIGBUS, &sigbus_oldact, NULL); if (ret) { /* Terminate QEMU since it can't recover from error */ - perror("os_mem_prealloc: failed to reinstall signal handler"); + perror("qemu_prealloc_mem: failed to reinstall signal handler"); exit(1); } qemu_mutex_unlock(&sigbus_mutex); diff --git a/util/oslib-win32.c b/util/oslib-win32.c index 5723d3eb4c..e1cb725ecc 100644 --- a/util/oslib-win32.c +++ b/util/oslib-win32.c @@ -268,14 +268,14 @@ int getpagesize(void) return system_info.dwPageSize; } -void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus, - Error **errp) +void qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads, + Error **errp) { int i; size_t pagesize = qemu_real_host_page_size(); - memory = (memory + pagesize - 1) & -pagesize; - for (i = 0; i < memory / pagesize; i++) { + sz = (sz + pagesize - 1) & -pagesize; + for (i = 0; i < sz / pagesize; i++) { memset(area + pagesize * i, 0, 1); } }