diff options
author | David Hildenbrand <david@redhat.com> | 2022-10-14 15:47:14 +0200 |
---|---|---|
committer | David Hildenbrand <david@redhat.com> | 2022-10-27 11:00:28 +0200 |
commit | 6556aadc18c560e493b29dd99cae2cbf86d214cb (patch) | |
tree | 7d4b15d6988db2f112fab919483a2b783ad7856a | |
parent | d0180f0acb142ca78e30857b8d8511ee9f3bd764 (diff) | |
download | qemu-6556aadc18c560e493b29dd99cae2cbf86d214cb.zip qemu-6556aadc18c560e493b29dd99cae2cbf86d214cb.tar.gz qemu-6556aadc18c560e493b29dd99cae2cbf86d214cb.tar.bz2 |
util: Cleanup and rename os_mem_prealloc()
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 <mprivozn@redhat.com>
Message-Id: <20221014134720.168738-2-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
-rw-r--r-- | backends/hostmem.c | 6 | ||||
-rw-r--r-- | hw/virtio/virtio-mem.c | 2 | ||||
-rw-r--r-- | include/qemu/osdep.h | 17 | ||||
-rw-r--r-- | softmmu/cpus.c | 2 | ||||
-rw-r--r-- | util/oslib-posix.c | 24 | ||||
-rw-r--r-- | util/oslib-win32.c | 8 |
6 files changed, 36 insertions, 23 deletions
diff --git a/backends/hostmem.c b/backends/hostmem.c index 4428e06..491cb10 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 30d03e9..0e9ef4f 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 b1c161c..e556e45 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 61b27ff..01c94fd 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 827a7aa..905cbc2 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 5723d3e..e1cb725 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); } } |