Commit Graph

6 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
fbfb858552 perf tools: Use calloc() where applicable
Instead of using zalloc(nr_entries * sizeof_entry) that is what calloc()
does.

In some places where linux/zalloc.h isn't needed, remove it, add when
needed and was getting it indirectly.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-04-08 19:21:05 -07:00
Zecheng Li
4fb7eefe6c perf annotate-data: Use DWARF location ranges to preserve reg state
When a function call occurs, caller-saved registers are typically
invalidated since the callee may clobber them. However, DWARF debug info
provides location ranges that indicate exactly where a variable is valid
in a register.

Track the DWARF location range end address in type_state_reg and use it
to determine if a caller-saved register should be preserved across a
call. If the current call address is within the DWARF-specified lifetime
of the variable, keep the register state valid instead of invalidating
it.

This improves type annotation for code where the compiler knows a
register value survives across calls (e.g., when the callee is known not
to clobber certain registers or when the value is reloaded after the
call at the same logical location).

Changes:
- Add `end` and `has_range` fields to die_var_type to capture DWARF
  location range information
- Add `lifetime_active` and `lifetime_end` fields to type_state_reg
- Check location lifetime before invalidating caller-saved registers

Signed-off-by: Zecheng Li <zli94@ncsu.edu>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-03-19 14:42:29 -07:00
Zecheng Li
d35b0d5877 perf annotate-data: Invalidate caller-saved regs for all calls
Previously, the x86 call handler returned early without invalidating
caller-saved registers when the call target symbol could not be resolved
(func == NULL). This violated the ABI which requires caller-saved
registers to be considered clobbered after any call instruction.

Fix this by:
1. Always invalidating caller-saved registers for any call instruction
   (except __fentry__ which preserves registers)
2. Using dl->ops.target.name as fallback when func->name is unavailable,
   allowing return type lookup for more call targets

This is a conservative change that may reduce type coverage for indirect
calls (e.g., callq *(%rax)) where we cannot determine the return type
but it ensures correctness.

Signed-off-by: Zecheng Li <zli94@ncsu.edu>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-03-19 14:42:29 -07:00
Zecheng Li
22b320777c perf annotate-data: Add invalidate_reg_state() helper for x86
Add a helper function to consistently invalidate register state instead
of field assignments. This ensures kind, ok, and copied_from are all
properly cleared when a register becomes invalid.

The helper sets:
- kind = TSR_KIND_INVALID
- ok = false
- copied_from = -1

Replace all invalidation patterns with calls to this helper. No
functional change and this removes some incorrect annotations that were
caused by incomplete invalidation (e.g. a obsolete copied_from from an
invalidated register).

Signed-off-by: Zecheng Li <zli94@ncsu.edu>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-03-19 14:42:29 -07:00
Ian Rogers
0e26ba5a87 perf disasm: Refactor arch__find and initialization of arch structs
Switch arch__find to using an ELF machine number rather than a
string.

Rather than an array of fixed size arch structs turn the init functions
into new functions indexed by the ELF machine they correspond to.

This allows data to be stored with a struct arch with the container_of
trick, so the priv variable can be removed.

Switch to using the thread to find the arch rather than the evsel as the
evsel only has limited notions of the running thread upon which
disassembly is performed.

Factor out the e_machine and e_flags into their own struct to make them
easier to pass around.

Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Aditya Bodkhe <aditya.b1@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Julia Lawall <Julia.Lawall@inria.fr>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Krzysztof Łopatowski <krzysztof.m.lopatowski@gmail.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <pjw@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sergei Trofimovich <slyich@gmail.com>
Cc: Shimin Guo <shimin.guo@skydio.com>
Cc: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Tianyou Li <tianyou.li@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zecheng Li <zecheng@google.com>
[ Include elf.h for EM_CSKY and friends and also conditionally define EM_CSKY_ABIMASK for old distros ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-23 16:58:39 -03:00
Ian Rogers
07b972ff09 perf disasm: Don't include C files from the arch directory
Move the arch instructions.c files into appropriately named files in
annotate-arch in the util directory.

Don't #include to compile the code, switch to building the files and fix
up the #includes accordingly.

Move powerpc specific disasm code out of disasm.c and into
annotate-powerpc.c.

Declarations and static removed as appropriate for the code to compile
as separate compilation units.

The e_machine and e_flags set up is moved to the disasm.c architectures
array so that later patches can sort by them.

Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Aditya Bodkhe <aditya.b1@linux.ibm.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Ghiti <alex@ghiti.fr>
Cc: Athira Rajeev <atrajeev@linux.ibm.com>
Cc: Bill Wendling <morbo@google.com>
Cc: Dr. David Alan Gilbert <linux@treblig.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Julia Lawall <Julia.Lawall@inria.fr>
Cc: Justin Stitt <justinstitt@google.com>
Cc: Krzysztof Łopatowski <krzysztof.m.lopatowski@gmail.com>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <pjw@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sergei Trofimovich <slyich@gmail.com>
Cc: Shimin Guo <shimin.guo@skydio.com>
Cc: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Cc: Thomas Falcon <thomas.falcon@intel.com>
Cc: Tianyou Li <tianyou.li@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zecheng Li <zecheng@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-23 16:58:38 -03:00