| Message ID | 20230316170149.4106586-4-jolsa@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/bpf/perf: Store build id in file object | expand |
On Thu, Mar 16, 2023 at 10:02 AM Jiri Olsa <jolsa@kernel.org> wrote: > > Use build id from file object in stackmap if it's available. > > The file's f_build_id is available (for CONFIG_FILE_BUILD_ID option) > when the file is mmap-ed, so it will be available (if present) when > used by stackmap. > > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > --- LGTM. Acked-by: Andrii Nakryiko <andrii@kernel.org> > kernel/bpf/stackmap.c | 24 +++++++++++++++++++++++- > 1 file changed, 23 insertions(+), 1 deletion(-) > > diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c > index 0f1d8dced933..14d27bd83081 100644 > --- a/kernel/bpf/stackmap.c > +++ b/kernel/bpf/stackmap.c > @@ -124,6 +124,28 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr) > return ERR_PTR(err); > } > > +#ifdef CONFIG_FILE_BUILD_ID > +static int vma_get_build_id(struct vm_area_struct *vma, unsigned char *build_id) > +{ > + struct build_id *bid; > + > + if (!vma->vm_file) > + return -EINVAL; > + bid = vma->vm_file->f_build_id; > + if (IS_ERR_OR_NULL(bid)) > + return bid ? PTR_ERR(bid) : -ENOENT; > + if (bid->sz > BUILD_ID_SIZE_MAX) > + return -EINVAL; > + memcpy(build_id, bid->data, bid->sz); > + return 0; > +} > +#else > +static int vma_get_build_id(struct vm_area_struct *vma, unsigned char *build_id) > +{ > + return build_id_parse(vma, build_id, NULL); > +} > +#endif > + > static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, > u64 *ips, u32 trace_nr, bool user) > { > @@ -156,7 +178,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, > goto build_id_valid; > } > vma = find_vma(current->mm, ips[i]); > - if (!vma || build_id_parse(vma, id_offs[i].build_id, NULL)) { > + if (!vma || vma_get_build_id(vma, id_offs[i].build_id)) { > /* per entry fall back to ips */ > id_offs[i].status = BPF_STACK_BUILD_ID_IP; > id_offs[i].ip = ips[i]; > -- > 2.39.2 >
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 0f1d8dced933..14d27bd83081 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -124,6 +124,28 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr) return ERR_PTR(err); } +#ifdef CONFIG_FILE_BUILD_ID +static int vma_get_build_id(struct vm_area_struct *vma, unsigned char *build_id) +{ + struct build_id *bid; + + if (!vma->vm_file) + return -EINVAL; + bid = vma->vm_file->f_build_id; + if (IS_ERR_OR_NULL(bid)) + return bid ? PTR_ERR(bid) : -ENOENT; + if (bid->sz > BUILD_ID_SIZE_MAX) + return -EINVAL; + memcpy(build_id, bid->data, bid->sz); + return 0; +} +#else +static int vma_get_build_id(struct vm_area_struct *vma, unsigned char *build_id) +{ + return build_id_parse(vma, build_id, NULL); +} +#endif + static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, u64 *ips, u32 trace_nr, bool user) { @@ -156,7 +178,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, goto build_id_valid; } vma = find_vma(current->mm, ips[i]); - if (!vma || build_id_parse(vma, id_offs[i].build_id, NULL)) { + if (!vma || vma_get_build_id(vma, id_offs[i].build_id)) { /* per entry fall back to ips */ id_offs[i].status = BPF_STACK_BUILD_ID_IP; id_offs[i].ip = ips[i];
Use build id from file object in stackmap if it's available. The file's f_build_id is available (for CONFIG_FILE_BUILD_ID option) when the file is mmap-ed, so it will be available (if present) when used by stackmap. Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- kernel/bpf/stackmap.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-)