diff mbox series

[PATCHv3,bpf-next,2/9] perf: Use file object build id in perf_event_mmap_event

Message ID 20230316170149.4106586-3-jolsa@kernel.org (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series mm/bpf/perf: Store build id in file object | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR fail PR summary
bpf/vmtest-bpf-next-VM_Test-1 success Logs for ${{ matrix.test }} on ${{ matrix.arch }} with ${{ matrix.toolchain }}
bpf/vmtest-bpf-next-VM_Test-2 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-3 fail Logs for build for aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-4 fail Logs for build for aarch64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-5 fail Logs for build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-6 fail Logs for build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-7 fail Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-8 success Logs for llvm-toolchain
bpf/vmtest-bpf-next-VM_Test-9 success Logs for set-matrix
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 63 this patch: 63
netdev/cc_maintainers warning 4 maintainers not CCed: mark.rutland@arm.com alexander.shishkin@linux.intel.com irogers@google.com namhyung@kernel.org
netdev/build_clang success Errors and warnings before: 18 this patch: 18
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 63 this patch: 63
netdev/checkpatch warning CHECK: No space is necessary after a cast WARNING: line length of 81 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Jiri Olsa March 16, 2023, 5:01 p.m. UTC 
Use build id from file object when available for perf's MMAP2 event
build id data.

The file's f_build_id is available (for CONFIG_FILE_BUILD_ID option)
when the file is mmap-ed and before the perf's callback is executed,
so we can use it, instead of reading it again.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 kernel/events/core.c | 43 +++++++++++++++++++++++++++++++++++++++----
 1 file changed, 39 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/kernel/events/core.c b/kernel/events/core.c
index f79fd8b87f75..3a5398dda6f6 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8527,6 +8527,9 @@  struct perf_mmap_event {
 	u32			prot, flags;
 	u8			build_id[BUILD_ID_SIZE_MAX];
 	u32			build_id_size;
+#ifdef CONFIG_FILE_BUILD_ID
+	struct build_id		*f_build_id;
+#endif
 
 	struct {
 		struct perf_event_header	header;
@@ -8539,6 +8542,38 @@  struct perf_mmap_event {
 	} event_id;
 };
 
+#ifdef CONFIG_FILE_BUILD_ID
+static void build_id_read(struct perf_mmap_event *mmap_event)
+{
+	struct vm_area_struct *vma = mmap_event->vma;
+
+	mmap_event->f_build_id = vma->vm_file ? vma->vm_file->f_build_id : NULL;
+}
+
+static bool has_build_id(struct perf_mmap_event *mmap_event)
+{
+	return !IS_ERR_OR_NULL(mmap_event->f_build_id);
+}
+
+#define build_id_data mmap_event->f_build_id->data
+#define build_id_size mmap_event->f_build_id->sz
+#else
+static void build_id_read(struct perf_mmap_event *mmap_event)
+{
+	struct vm_area_struct *vma = mmap_event->vma;
+
+	build_id_parse(vma, mmap_event->build_id, &mmap_event->build_id_size);
+}
+
+static bool has_build_id(struct perf_mmap_event *mmap_event)
+{
+	return mmap_event->build_id_size;
+}
+
+#define build_id_data mmap_event->build_id
+#define build_id_size mmap_event->build_id_size
+#endif
+
 static int perf_event_mmap_match(struct perf_event *event,
 				 void *data)
 {
@@ -8583,7 +8618,7 @@  static void perf_event_mmap_output(struct perf_event *event,
 	mmap_event->event_id.pid = perf_event_pid(event, current);
 	mmap_event->event_id.tid = perf_event_tid(event, current);
 
-	use_build_id = event->attr.build_id && mmap_event->build_id_size;
+	use_build_id = event->attr.build_id && has_build_id(mmap_event);
 
 	if (event->attr.mmap2 && use_build_id)
 		mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_BUILD_ID;
@@ -8592,10 +8627,10 @@  static void perf_event_mmap_output(struct perf_event *event,
 
 	if (event->attr.mmap2) {
 		if (use_build_id) {
-			u8 size[4] = { (u8) mmap_event->build_id_size, 0, 0, 0 };
+			u8 size[4] = { (u8) build_id_size, 0, 0, 0 };
 
 			__output_copy(&handle, size, 4);
-			__output_copy(&handle, mmap_event->build_id, BUILD_ID_SIZE_MAX);
+			__output_copy(&handle, build_id_data, BUILD_ID_SIZE_MAX);
 		} else {
 			perf_output_put(&handle, mmap_event->maj);
 			perf_output_put(&handle, mmap_event->min);
@@ -8727,7 +8762,7 @@  static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 	mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size;
 
 	if (atomic_read(&nr_build_id_events))
-		build_id_parse(vma, mmap_event->build_id, &mmap_event->build_id_size);
+		build_id_read(mmap_event);
 
 	perf_iterate_sb(perf_event_mmap_output,
 		       mmap_event,