+++ /dev/null
-#ifndef _LTTNG_WRAPPER_VMALLOC_H
-#define _LTTNG_WRAPPER_VMALLOC_H
-
-/*
- * wrapper/vmalloc.h
- *
- * wrapper around vmalloc_sync_all. Using KALLSYMS to get its address when
- * available, else we need to have a kernel that exports this function to GPL
- * modules.
- *
- * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <linux/version.h>
-#include <linux/vmalloc.h>
-#include <linux/mm.h>
-
-#ifdef CONFIG_KALLSYMS
-
-#include <linux/kallsyms.h>
-#include <wrapper/kallsyms.h>
-
-static inline
-void wrapper_vmalloc_sync_all(void)
-{
- void (*vmalloc_sync_all_sym)(void);
-
- vmalloc_sync_all_sym = (void *) kallsyms_lookup_funcptr("vmalloc_sync_all");
- if (vmalloc_sync_all_sym) {
- vmalloc_sync_all_sym();
- } else {
-#ifdef CONFIG_X86
- /*
- * Only x86 needs vmalloc_sync_all to make sure LTTng does not
- * trigger recursive page faults.
- */
- printk_once(KERN_WARNING "LTTng: vmalloc_sync_all symbol lookup failed.\n");
- printk_once(KERN_WARNING "Page fault handler and NMI tracing might trigger faults.\n");
-#endif
- }
-}
-#else
-
-static inline
-void wrapper_vmalloc_sync_all(void)
-{
- return vmalloc_sync_all();
-}
-#endif
-
-#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,12,0))
-static inline
-void *lttng_kvmalloc_node(unsigned long size, gfp_t flags, int node)
-{
- void *ret;
-
- ret = kvmalloc_node(size, flags, node);
- if (is_vmalloc_addr(ret)) {
- /*
- * Make sure we don't trigger recursive page faults in the
- * tracing fast path.
- */
- wrapper_vmalloc_sync_all();
- }
- return ret;
-}
-
-static inline
-void *lttng_kvzalloc_node(unsigned long size, gfp_t flags, int node)
-{
- return lttng_kvmalloc_node(size, flags | __GFP_ZERO, node);
-}
-
-static inline
-void *lttng_kvmalloc(unsigned long size, gfp_t flags)
-{
- return lttng_kvmalloc_node(size, flags, NUMA_NO_NODE);
-}
-
-static inline
-void *lttng_kvzalloc(unsigned long size, gfp_t flags)
-{
- return lttng_kvzalloc_node(size, flags, NUMA_NO_NODE);
-}
-
-static inline
-void lttng_kvfree(const void *addr)
-{
- kvfree(addr);
-}
-
-#else
-
-#include <linux/slab.h>
-
-static inline
-void print_vmalloc_node_range_warning(void)
-{
- printk_once(KERN_WARNING "LTTng: __vmalloc_node_range symbol lookup failed.\n");
- printk_once(KERN_WARNING "Tracer performance will be degraded on NUMA systems.\n");
- printk_once(KERN_WARNING "Please rebuild your kernel with CONFIG_KALLSYMS enabled.\n");
-}
-
-/*
- * kallsyms wrapper of __vmalloc_node with a fallback to kmalloc_node.
- */
-static inline
-void *__lttng_vmalloc_node_range(unsigned long size, unsigned long align,
- unsigned long start, unsigned long end, gfp_t gfp_mask,
- pgprot_t prot, unsigned long vm_flags, int node,
- const void *caller)
-{
-#ifdef CONFIG_KALLSYMS
- /*
- * If we have KALLSYMS, get * __vmalloc_node_range which is not exported.
- */
- void *(*lttng__vmalloc_node_range)(unsigned long size, unsigned long align,
- unsigned long start, unsigned long end, gfp_t gfp_mask,
- pgprot_t prot, unsigned long vm_flags, int node,
- const void *caller);
-
- lttng__vmalloc_node_range = (void *) kallsyms_lookup_funcptr("__vmalloc_node_range");
- if (lttng__vmalloc_node_range)
- return lttng__vmalloc_node_range(size, align, start, end, gfp_mask, prot,
- vm_flags, node, caller);
-#endif
- if (node != NUMA_NO_NODE)
- print_vmalloc_node_range_warning();
- return __vmalloc(size, gfp_mask, prot);
-}
-
-/**
- * lttng_kvmalloc_node - attempt to allocate physically contiguous memory, but upon
- * failure, fall back to non-contiguous (vmalloc) allocation.
- * @size: size of the request.
- * @flags: gfp mask for the allocation - must be compatible with GFP_KERNEL.
- *
- * Uses kmalloc to get the memory but if the allocation fails then falls back
- * to the vmalloc allocator. Use lttng_kvfree to free the memory.
- *
- * Reclaim modifiers - __GFP_NORETRY, __GFP_REPEAT and __GFP_NOFAIL are not supported
- */
-static inline
-void *lttng_kvmalloc_node(unsigned long size, gfp_t flags, int node)
-{
- void *ret;
-
- /*
- * vmalloc uses GFP_KERNEL for some internal allocations (e.g page tables)
- * so the given set of flags has to be compatible.
- */
- WARN_ON_ONCE((flags & GFP_KERNEL) != GFP_KERNEL);
-
- /*
- * If the allocation fits in a single page, do not fallback.
- */
- if (size <= PAGE_SIZE) {
- return kmalloc_node(size, flags, node);
- }
-
- /*
- * Make sure that larger requests are not too disruptive - no OOM
- * killer and no allocation failure warnings as we have a fallback
- */
- ret = kmalloc_node(size, flags | __GFP_NOWARN | __GFP_NORETRY, node);
- if (!ret) {
- ret = __lttng_vmalloc_node_range(size, 1,
- VMALLOC_START, VMALLOC_END,
- flags | __GFP_HIGHMEM, PAGE_KERNEL, 0,
- node, __builtin_return_address(0));
- /*
- * Make sure we don't trigger recursive page faults in the
- * tracing fast path.
- */
- wrapper_vmalloc_sync_all();
- }
- return ret;
-}
-
-static inline
-void *lttng_kvzalloc_node(unsigned long size, gfp_t flags, int node)
-{
- return lttng_kvmalloc_node(size, flags | __GFP_ZERO, node);
-}
-
-static inline
-void *lttng_kvmalloc(unsigned long size, gfp_t flags)
-{
- return lttng_kvmalloc_node(size, flags, NUMA_NO_NODE);
-}
-
-static inline
-void *lttng_kvzalloc(unsigned long size, gfp_t flags)
-{
- return lttng_kvzalloc_node(size, flags, NUMA_NO_NODE);
-}
-
-static inline
-void lttng_kvfree(const void *addr)
-{
- if (is_vmalloc_addr(addr)) {
- vfree(addr);
- } else {
- kfree(addr);
- }
-}
-#endif
-
-#endif /* _LTTNG_WRAPPER_VMALLOC_H */
projects / lttng-modules.git / blobdiff