uprobes: kill uprobe_register_refctr()

It doesn't make any sense to have 2 versions of _register(). Note that
trace_uprobe_enable(), the only user of uprobe_register(), doesn't need
to check tu->ref_ctr_offset to decide which one should be used, it could
safely pass ref_ctr_offset == 0 to uprobe_register_refctr().

Add this argument to uprobe_register(), update the callers, and kill
uprobe_register_refctr().

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240801132728.GA8800@redhat.com

diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index a270a5892ab4f54f8d0d3fdf84cbdfd7bf5f7eeb..788813c0b8fc773db77b330d4763e72de6102e8c 100644 (file)
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -112,8 +112,7 @@ extern bool is_trap_insn(uprobe_opcode_t *insn);
 extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
 extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
 extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_t);
-extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
-extern int uprobe_register_refctr(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
+extern int uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
 extern int uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool);
 extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
 extern int uprobe_mmap(struct vm_area_struct *vma);
@@ -154,11 +153,7 @@ static inline void uprobes_init(void)
 #define uprobe_get_trap_addr(regs)     instruction_pointer(regs)
 
 static inline int
-uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
-{
-       return -ENOSYS;
-}
-static inline int uprobe_register_refctr(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc)
+uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc)
 {
        return -ENOSYS;
 }

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index e9b092acc71bea139c02b5527dfa10b76c6502cc..3a80154bc4c79c25fd1769be1c0baa14cec3370e 100644 (file)
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -1121,25 +1121,26 @@ void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consume
 EXPORT_SYMBOL_GPL(uprobe_unregister);
 
 /*
- * __uprobe_register - register a probe
+ * uprobe_register - register a probe
  * @inode: the file in which the probe has to be placed.
  * @offset: offset from the start of the file.
+ * @ref_ctr_offset: offset of SDT marker / reference counter
  * @uc: information on howto handle the probe..
  *
- * Apart from the access refcount, __uprobe_register() takes a creation
+ * Apart from the access refcount, uprobe_register() takes a creation
  * refcount (thro alloc_uprobe) if and only if this @uprobe is getting
  * inserted into the rbtree (i.e first consumer for a @inode:@offset
  * tuple).  Creation refcount stops uprobe_unregister from freeing the
  * @uprobe even before the register operation is complete. Creation
  * refcount is released when the last @uc for the @uprobe
- * unregisters. Caller of __uprobe_register() is required to keep @inode
+ * unregisters. Caller of uprobe_register() is required to keep @inode
  * (and the containing mount) referenced.
  *
  * Return errno if it cannot successully install probes
  * else return 0 (success)
  */
-static int __uprobe_register(struct inode *inode, loff_t offset,
-                            loff_t ref_ctr_offset, struct uprobe_consumer *uc)
+int uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset,
+                   struct uprobe_consumer *uc)
 {
        struct uprobe *uprobe;
        int ret;
@@ -1189,21 +1190,8 @@ static int __uprobe_register(struct inode *inode, loff_t offset,
                goto retry;
        return ret;
 }
-
-int uprobe_register(struct inode *inode, loff_t offset,
-                   struct uprobe_consumer *uc)
-{
-       return __uprobe_register(inode, offset, 0, uc);
-}
 EXPORT_SYMBOL_GPL(uprobe_register);
 
-int uprobe_register_refctr(struct inode *inode, loff_t offset,
-                          loff_t ref_ctr_offset, struct uprobe_consumer *uc)
-{
-       return __uprobe_register(inode, offset, ref_ctr_offset, uc);
-}
-EXPORT_SYMBOL_GPL(uprobe_register_refctr);
-
 /*
  * uprobe_apply - unregister an already registered probe.
  * @inode: the file in which the probe has to be removed.

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index cd098846e251cdaabc3f2b16242760fe26606273..afa909e17824df09cafa3363a4544f0c449c35dd 100644 (file)
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3480,10 +3480,10 @@ int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *pr
                      &bpf_uprobe_multi_link_lops, prog);
 
        for (i = 0; i < cnt; i++) {
-               err = uprobe_register_refctr(d_real_inode(link->path.dentry),
-                                            uprobes[i].offset,
-                                            uprobes[i].ref_ctr_offset,
-                                            &uprobes[i].consumer);
+               err = uprobe_register(d_real_inode(link->path.dentry),
+                                     uprobes[i].offset,
+                                     uprobes[i].ref_ctr_offset,
+                                     &uprobes[i].consumer);
                if (err) {
                        bpf_uprobe_unregister(&path, uprobes, i);
                        goto error_free;

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index c98e3b3386badb60a187e86e557ed4c26f76c966..1f590f989c1e2e7d3b29d637cd37a6f68eda4d04 100644 (file)
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -1089,12 +1089,7 @@ static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter)
        tu->consumer.filter = filter;
        tu->inode = d_real_inode(tu->path.dentry);
 
-       if (tu->ref_ctr_offset)
-               ret = uprobe_register_refctr(tu->inode, tu->offset,
-                               tu->ref_ctr_offset, &tu->consumer);
-       else
-               ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
-
+       ret = uprobe_register(tu->inode, tu->offset, tu->ref_ctr_offset, &tu->consumer);
        if (ret)
                tu->inode = NULL;
 

diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
index 72f565af4f829ef5431351eb22f592e181fa3054..55f6905de743fb07b55a6952fd208df539f64241 100644 (file)
--- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
+++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c
@@ -458,8 +458,8 @@ static int testmod_register_uprobe(loff_t offset)
        if (err)
                goto out;
 
-       err = uprobe_register_refctr(d_real_inode(uprobe.path.dentry),
-                                    offset, 0, &uprobe.consumer);
+       err = uprobe_register(d_real_inode(uprobe.path.dentry),
+                             offset, 0, &uprobe.consumer);
        if (err)
                path_put(&uprobe.path);
        else