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Linus Torvalds authored
Merge tag 'trace-sorttable-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing / sorttable updates from Steven Rostedt:

 - Implement arm64 build time sorting of the mcount location table

   When gcc is used to build arm64, the mcount_loc section is all zeros
   in the vmlinux elf file. The addresses are stored in the Elf_Rela
   location.

   To sort at build time, an array is allocated and the addresses are
   added to it via the content of the mcount_loc section as well as he
   Elf_Rela data. After sorting, the information is put back into the
   Elf_Rela which now has the section sorted.

 - Make sorting of mcount location table for arm64 work with clang as
   well

   When clang is used, the mcount_loc section contains the addresses,
   unlike the gcc build. An array is still created and the sorting works
   for both methods.

 - Remove weak functions from the mcount_loc section

   Have the sorttable code pass in the data of functions defined via
   'nm -S' which shows the functions as well as their sizes. Using this
   information the sorttable code can determine if a function in the
   mcount_loc section was weak and overridden. If the function is not
   found, it is set to be zero. On boot, when the mcount_loc section is
   read and the ftrace table is created, if the address in the
   mcount_loc is not in the kernel core text then it is removed and not
   added to the ftrace_filter_functions (the functions that can be
   attached by ftrace callbacks).

 - Update and fix the reporting of how much data is used for ftrace
   functions

   On boot, a report of how many pages were used by the ftrace table as
   well as how they were grouped (the table holds a list of sections
   that are groups of pages that were able to be allocated). The
   removing of the weak functions required the accounting to be updated.

* tag 'trace-sorttable-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  scripts/sorttable: Allow matches to functions before function entry
  scripts/sorttable: Use normal sort if theres no relocs in the mcount section
  ftrace: Check against is_kernel_text() instead of kaslr_offset()
  ftrace: Test mcount_loc addr before calling ftrace_call_addr()
  ftrace: Have ftrace pages output reflect freed pages
  ftrace: Update the mcount_loc check of skipped entries
  scripts/sorttable: Zero out weak functions in mcount_loc table
  scripts/sorttable: Always use an array for the mcount_loc sorting
  scripts/sorttable: Have mcount rela sort use direct values
  arm64: scripts/sorttable: Implement sorting mcount_loc at boot for arm64
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Linux kernel
============

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