Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf updates from Thomas Gleixner:
 "Kernel:
   - Improve kallsyms coverage
   - Add x86 entry trampolines to kcore
   - Fix ARM SPE handling
   - Correct PPC event post processing

  Tools:
   - Make the build system more robust
   - Small fixes and enhancements all over the place
   - Update kernel ABI header copies
   - Preparatory work for converting libtraceevnt to a shared library
   - License cleanups"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits)
  tools arch: Update arch/x86/lib/memcpy_64.S copy used in 'perf bench mem memcpy'
  tools arch x86: Update tools's copy of cpufeatures.h
  perf python: Fix pyrf_evlist__read_on_cpu() interface
  perf mmap: Store real cpu number in 'struct perf_mmap'
  perf tools: Remove ext from struct kmod_path
  perf tools: Add gzip_is_compressed function
  perf tools: Add lzma_is_compressed function
  perf tools: Add is_compressed callback to compressions array
  perf tools: Move the temp file processing into decompress_kmodule
  perf tools: Use compression id in decompress_kmodule()
  perf tools: Store compression id into struct dso
  perf tools: Add compression id into 'struct kmod_path'
  perf tools: Make is_supported_compression() static
  perf tools: Make decompress_to_file() function static
  perf tools: Get rid of dso__needs_decompress() call in __open_dso()
  perf tools: Get rid of dso__needs_decompress() call in symbol__disassemble()
  perf tools: Get rid of dso__needs_decompress() call in read_object_code()
  tools lib traceevent: Change to SPDX License format
  perf llvm: Allow passing options to llc in addition to clang
  perf parser: Improve error message for PMU address filters
  ...

1 files changed, 37 insertions, 14 deletions

diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index a23e21ada81b..02a0b01380d8 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -432,6 +432,7 @@ int sprint_backtrace(char *buffer, unsigned long address)
 /* To avoid using get_symbol_offset for every symbol, we carry prefix along. */
 struct kallsym_iter {
         loff_t pos;
+        loff_t pos_arch_end;
         loff_t pos_mod_end;
         loff_t pos_ftrace_mod_end;
         unsigned long value;
@@ -443,9 +444,29 @@ struct kallsym_iter {
         int show_value;
 };
 
+int __weak arch_get_kallsym(unsigned int symnum, unsigned long *value,
+                            char *type, char *name)
+{
+        return -EINVAL;
+}
+
+static int get_ksymbol_arch(struct kallsym_iter *iter)
+{
+        int ret = arch_get_kallsym(iter->pos - kallsyms_num_syms,
+                                   &iter->value, &iter->type,
+                                   iter->name);
+
+        if (ret < 0) {
+                iter->pos_arch_end = iter->pos;
+                return 0;
+        }
+
+        return 1;
+}
+
 static int get_ksymbol_mod(struct kallsym_iter *iter)
 {
-        int ret = module_get_kallsym(iter->pos - kallsyms_num_syms,
+        int ret = module_get_kallsym(iter->pos - iter->pos_arch_end,
                                      &iter->value, &iter->type,
                                      iter->name, iter->module_name,
                                      &iter->exported);
@@ -501,32 +522,34 @@ static void reset_iter(struct kallsym_iter *iter, loff_t new_pos)
         iter->nameoff = get_symbol_offset(new_pos);
         iter->pos = new_pos;
         if (new_pos == 0) {
+                iter->pos_arch_end = 0;
                 iter->pos_mod_end = 0;
                 iter->pos_ftrace_mod_end = 0;
         }
 }
 
+/*
+ * The end position (last + 1) of each additional kallsyms section is recorded
+ * in iter->pos_..._end as each section is added, and so can be used to
+ * determine which get_ksymbol_...() function to call next.
+ */
 static int update_iter_mod(struct kallsym_iter *iter, loff_t pos)
 {
         iter->pos = pos;
 
-        if (iter->pos_ftrace_mod_end > 0 &&
-            iter->pos_ftrace_mod_end < iter->pos)
-                return get_ksymbol_bpf(iter);
+        if ((!iter->pos_arch_end || iter->pos_arch_end > pos) &&
+            get_ksymbol_arch(iter))
+                return 1;
 
-        if (iter->pos_mod_end > 0 &&
-            iter->pos_mod_end < iter->pos) {
-                if (!get_ksymbol_ftrace_mod(iter))
-                        return get_ksymbol_bpf(iter);
+        if ((!iter->pos_mod_end || iter->pos_mod_end > pos) &&
+            get_ksymbol_mod(iter))
                 return 1;
-        }
 
-        if (!get_ksymbol_mod(iter)) {
-                if (!get_ksymbol_ftrace_mod(iter))
-                        return get_ksymbol_bpf(iter);
-        }
+        if ((!iter->pos_ftrace_mod_end || iter->pos_ftrace_mod_end > pos) &&
+            get_ksymbol_ftrace_mod(iter))
+                return 1;
 
-        return 1;
+        return get_ksymbol_bpf(iter);
 }
 
 /* Returns false if pos at or past end of file. */