* sdt.h (STAP_SEMAPHORE): New. Add guard to utrace probe points.

* itrace.h (__access_process_vm): Moved from here...
* runtime/access_process_vm.h: New.  ...to here.
* translate.cxx (translate_pass): Include access_process_vm.h
* session.h (sdt_semaphore_addr): New.
* tapsets.cxx (sdt_query::record_semaphore): New.  Record sdt_semaphore_addr.
(uprobe_derived_probe_group::emit_module_decls): Allow for uprobe guard variable to be set and unset.
(uprobe_derived_probe_group::emit_module_decls): Likewise.
(uprobe_derived_probe_group::emit_module_exit): Likewise.
* tapset-utrace.cxx (utrace_derived_probe_group::emit_probe_decl): Likewise.
(utrace_derived_probe_group::emit_module_decls): Likewise.
(utrace_derived_probe_group::emit_module_exit): Likewise.

1 files changed, 1 insertions, 53 deletions

diff --git a/runtime/itrace.c b/runtime/itrace.c
index 6fe39db4..03e1e403 100644
--- a/runtime/itrace.c
+++ b/runtime/itrace.c
@@ -77,60 +77,8 @@ static struct itrace_info *create_itrace_info(
 	struct task_struct *tsk, u32 step_flag,
 	struct stap_itrace_probe *itrace_probe);
 
-/*
- * The kernel's access_process_vm is not exported in kernel.org kernels, although
- * some distros export it on some architectures.  To workaround this inconsistency,
- * we copied and pasted it here.  Fortunately, everything it calls is exported.
- */
-#include <linux/pagemap.h>
-#include <asm/cacheflush.h>
-static int __access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
-{
-	struct mm_struct *mm;
-	struct vm_area_struct *vma;
-	struct page *page;
-	void *old_buf = buf;
-
-	mm = get_task_mm(tsk);
-	if (!mm)
-		return 0;
-
-	down_read(&mm->mmap_sem);
-	/* ignore errors, just check how much was sucessfully transfered */
-	while (len) {
-		int bytes, ret, offset;
-		void *maddr;
 
-		ret = get_user_pages(tsk, mm, addr, 1,
-				     write, 1, &page, &vma);
-		if (ret <= 0)
-			break;
-
-		bytes = len;
-		offset = addr & (PAGE_SIZE-1);
-		if (bytes > PAGE_SIZE-offset)
-			bytes = PAGE_SIZE-offset;
-
-		maddr = kmap(page);
-		if (write) {
-			copy_to_user_page(vma, page, addr,
-					  maddr + offset, buf, bytes);
-			set_page_dirty_lock(page);
-		} else {
-			copy_from_user_page(vma, page, addr,
-					    buf, maddr + offset, bytes);
-		}
-		kunmap(page);
-		page_cache_release(page);
-		len -= bytes;
-		buf += bytes;
-		addr += bytes;
-	}
-	up_read(&mm->mmap_sem);
-	mmput(mm);
-
-	return buf - old_buf;
-}
+/* Note: __access_process_vm moved to access_process_vm.h */
 
 #ifdef UTRACE_ORIG_VERSION
 static u32 usr_itrace_report_quiesce(struct utrace_attached_engine *engine,