From e199f7ad4df8b2c2efad0acdea91b936c130261c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Mon, 20 Nov 2023 13:49:30 +0100 Subject: [PATCH] backends: Simplify host_memory_backend_memory_complete() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return early if bc->alloc is NULL. De-indent the if() ladder. Note, this avoids a pointless call to error_propagate() with errp=NULL at the 'out:' label. Change trivial when reviewed with 'git-diff --ignore-all-space'. Signed-off-by: Philippe Mathieu-Daudé Reviewed-by: Manos Pitsidianakis Reviewed-by: Gavin Shan Message-Id: <20231120213301.24349-16-philmd@linaro.org> --- backends/hostmem.c | 133 +++++++++++++++++++++++---------------------- 1 file changed, 67 insertions(+), 66 deletions(-) diff --git a/backends/hostmem.c b/backends/hostmem.c index 747e7838c0..1723c19165 100644 --- a/backends/hostmem.c +++ b/backends/hostmem.c @@ -328,83 +328,84 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp) void *ptr; uint64_t sz; - if (bc->alloc) { - bc->alloc(backend, &local_err); - if (local_err) { - goto out; - } + if (!bc->alloc) { + return; + } + bc->alloc(backend, &local_err); + if (local_err) { + goto out; + } - ptr = memory_region_get_ram_ptr(&backend->mr); - sz = memory_region_size(&backend->mr); + ptr = memory_region_get_ram_ptr(&backend->mr); + sz = memory_region_size(&backend->mr); - if (backend->merge) { - qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE); - } - if (!backend->dump) { - qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP); - } + if (backend->merge) { + qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE); + } + if (!backend->dump) { + qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP); + } #ifdef CONFIG_NUMA - unsigned long lastbit = find_last_bit(backend->host_nodes, MAX_NODES); - /* lastbit == MAX_NODES means maxnode = 0 */ - unsigned long maxnode = (lastbit + 1) % (MAX_NODES + 1); - /* ensure policy won't be ignored in case memory is preallocated - * before mbind(). note: MPOL_MF_STRICT is ignored on hugepages so - * this doesn't catch hugepage case. */ - unsigned flags = MPOL_MF_STRICT | MPOL_MF_MOVE; - int mode = backend->policy; + unsigned long lastbit = find_last_bit(backend->host_nodes, MAX_NODES); + /* lastbit == MAX_NODES means maxnode = 0 */ + unsigned long maxnode = (lastbit + 1) % (MAX_NODES + 1); + /* ensure policy won't be ignored in case memory is preallocated + * before mbind(). note: MPOL_MF_STRICT is ignored on hugepages so + * this doesn't catch hugepage case. */ + unsigned flags = MPOL_MF_STRICT | MPOL_MF_MOVE; + int mode = backend->policy; - /* check for invalid host-nodes and policies and give more verbose - * error messages than mbind(). */ - if (maxnode && backend->policy == MPOL_DEFAULT) { - error_setg(errp, "host-nodes must be empty for policy default," - " or you should explicitly specify a policy other" - " than default"); - return; - } else if (maxnode == 0 && backend->policy != MPOL_DEFAULT) { - error_setg(errp, "host-nodes must be set for policy %s", - HostMemPolicy_str(backend->policy)); - return; - } + /* check for invalid host-nodes and policies and give more verbose + * error messages than mbind(). */ + if (maxnode && backend->policy == MPOL_DEFAULT) { + error_setg(errp, "host-nodes must be empty for policy default," + " or you should explicitly specify a policy other" + " than default"); + return; + } else if (maxnode == 0 && backend->policy != MPOL_DEFAULT) { + error_setg(errp, "host-nodes must be set for policy %s", + HostMemPolicy_str(backend->policy)); + return; + } - /* We can have up to MAX_NODES nodes, but we need to pass maxnode+1 - * as argument to mbind() due to an old Linux bug (feature?) which - * cuts off the last specified node. This means backend->host_nodes - * must have MAX_NODES+1 bits available. - */ - assert(sizeof(backend->host_nodes) >= - BITS_TO_LONGS(MAX_NODES + 1) * sizeof(unsigned long)); - assert(maxnode <= MAX_NODES); + /* We can have up to MAX_NODES nodes, but we need to pass maxnode+1 + * as argument to mbind() due to an old Linux bug (feature?) which + * cuts off the last specified node. This means backend->host_nodes + * must have MAX_NODES+1 bits available. + */ + assert(sizeof(backend->host_nodes) >= + BITS_TO_LONGS(MAX_NODES + 1) * sizeof(unsigned long)); + assert(maxnode <= MAX_NODES); #ifdef HAVE_NUMA_HAS_PREFERRED_MANY - if (mode == MPOL_PREFERRED && numa_has_preferred_many() > 0) { - /* - * Replace with MPOL_PREFERRED_MANY otherwise the mbind() below - * silently picks the first node. - */ - mode = MPOL_PREFERRED_MANY; - } + if (mode == MPOL_PREFERRED && numa_has_preferred_many() > 0) { + /* + * Replace with MPOL_PREFERRED_MANY otherwise the mbind() below + * silently picks the first node. + */ + mode = MPOL_PREFERRED_MANY; + } #endif - if (maxnode && - mbind(ptr, sz, mode, backend->host_nodes, maxnode + 1, flags)) { - if (backend->policy != MPOL_DEFAULT || errno != ENOSYS) { - error_setg_errno(errp, errno, - "cannot bind memory to host NUMA nodes"); - return; - } + if (maxnode && + mbind(ptr, sz, mode, backend->host_nodes, maxnode + 1, flags)) { + if (backend->policy != MPOL_DEFAULT || errno != ENOSYS) { + error_setg_errno(errp, errno, + "cannot bind memory to host NUMA nodes"); + return; } + } #endif - /* Preallocate memory after the NUMA policy has been instantiated. - * This is necessary to guarantee memory is allocated with - * specified NUMA policy in place. - */ - if (backend->prealloc) { - qemu_prealloc_mem(memory_region_get_fd(&backend->mr), ptr, sz, - backend->prealloc_threads, - backend->prealloc_context, &local_err); - if (local_err) { - goto out; - } + /* Preallocate memory after the NUMA policy has been instantiated. + * This is necessary to guarantee memory is allocated with + * specified NUMA policy in place. + */ + if (backend->prealloc) { + qemu_prealloc_mem(memory_region_get_fd(&backend->mr), ptr, sz, + backend->prealloc_threads, + backend->prealloc_context, &local_err); + if (local_err) { + goto out; } } out: