tracing: use %ps format string to print symbols

clang started warning about excessive stack usage in
hist_trigger_print_key()

kernel/trace/trace_events_hist.c:4723:13: error: stack frame size (1336) exceeds limit (1024) in function 'hist_trigger_print_key' [-Werror,-Wframe-larger-than]

The problem is that there are two 512-byte arrays on the stack if
hist_trigger_stacktrace_print() gets inlined. I don't think this has
changed in the past five years, but something probably changed the
inlining decisions made by the compiler, so the problem is now made
more obvious.

Rather than printing the symbol names into separate buffers, it
seems we can simply use the special %ps format string modifier
to print the pointers symbolically and get rid of both buffers.

Marking hist_trigger_stacktrace_print() would be a simpler
way of avoiding the warning, but that would not address the
excessive stack usage.

Link: https://lkml.kernel.org/r/[email protected]

Fixes: 69a0200c2e25 ("tracing: Add hist trigger support for stacktraces as keys")
Link: https://lore.kernel.org/all/[email protected]/
Reviewed-by: Tom Zanussi <[email protected]>
Tested-by: Tom Zanussi <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

0 files changed, 0 insertions, 0 deletions