linux_dsm_epyc7002/kernel/trace
Rasmus Villemoes ff14417c0a kernel/trace/blktrace.c: use strreplace() in do_blk_trace_setup()
Part of the disassembly of do_blk_trace_setup:

    231b:       e8 00 00 00 00          callq  2320 <do_blk_trace_setup+0x50>
                        231c: R_X86_64_PC32     strlen+0xfffffffffffffffc
    2320:       eb 0a                   jmp    232c <do_blk_trace_setup+0x5c>
    2322:       66 0f 1f 44 00 00       nopw   0x0(%rax,%rax,1)
    2328:       48 83 c3 01             add    $0x1,%rbx
    232c:       48 39 d8                cmp    %rbx,%rax
    232f:       76 47                   jbe    2378 <do_blk_trace_setup+0xa8>
    2331:       41 80 3c 1c 2f          cmpb   $0x2f,(%r12,%rbx,1)
    2336:       75 f0                   jne    2328 <do_blk_trace_setup+0x58>
    2338:       41 c6 04 1c 5f          movb   $0x5f,(%r12,%rbx,1)
    233d:       4c 89 e7                mov    %r12,%rdi
    2340:       e8 00 00 00 00          callq  2345 <do_blk_trace_setup+0x75>
                        2341: R_X86_64_PC32     strlen+0xfffffffffffffffc
    2345:       eb e1                   jmp    2328 <do_blk_trace_setup+0x58>

Yep, that's right: gcc isn't smart enough to realize that replacing '/' by
'_' cannot change the strlen(), so we call it again and again (at least
when a '/' is found).  Even if gcc were that smart, this construction
would still loop over the string twice, once for the initial strlen() call
and then the open-coded loop.

Let's simply use strreplace() instead.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Liked-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25 17:00:40 -07:00
..
blktrace.c kernel/trace/blktrace.c: use strreplace() in do_blk_trace_setup() 2015-06-25 17:00:40 -07:00
bpf_trace.c bpf: let kprobe programs use bpf_get_smp_processor_id() helper 2015-06-15 15:53:50 -07:00
ftrace.c Some clean ups and small fixes, but the biggest change is the addition 2015-04-14 10:49:03 -07:00
Kconfig Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-14 14:37:47 -07:00
Makefile bpf: Fix the build on BPF_SYSCALL=y && !CONFIG_TRACING kernels, make it more configurable 2015-04-02 16:28:06 +02:00
power-traces.c PM / sleep: export suspend_resume trace event 2015-01-30 02:10:41 +01:00
ring_buffer_benchmark.c ring-buffer-benchmark: Fix the wrong sched_priority of producer 2015-06-11 09:27:58 -04:00
ring_buffer.c ring-buffer: Remove duplicate use of '&' in recursive code 2015-03-30 13:36:31 -04:00
rpm-traces.c PM / Runtime: Introduce trace points for tracing rpm_* functions 2011-09-27 22:53:27 +02:00
trace_benchmark.c tracing: Only calculate stats of tracepoint benchmarks for 2^32 times 2014-06-06 00:41:38 -04:00
trace_benchmark.h tracing: Add tracepoint benchmark tracepoint 2014-05-29 22:49:54 -04:00
trace_branch.c tracing: Remove unneeded includes of debugfs.h and fs.h 2015-01-22 11:19:48 -05:00
trace_clock.c tracing: Fix wraparound problems in "uptime" trace clock 2014-07-21 09:56:12 -04:00
trace_entries.h tracing: %pF is only for function pointers 2015-03-25 08:57:22 -04:00
trace_event_perf.c perf: Avoid horrible stack usage 2015-01-14 15:11:45 +01:00
trace_events_filter_test.h tracing/filter: Add startup tests for events filter 2011-08-19 14:35:59 -04:00
trace_events_filter.c kernel/trace/trace_events_filter.c: use strreplace() 2015-06-25 17:00:40 -07:00
trace_events_trigger.c trace: Replace single-character seq_puts with seq_putc 2014-11-14 07:55:55 -05:00
trace_events.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
trace_export.c tracing: remove ftrace:function TRACE_EVENT_FL_USE_CALL_FILTER flag 2015-03-25 08:57:23 -04:00
trace_functions_graph.c This adds three fixes for the tracing code. 2015-04-22 11:27:36 -07:00
trace_functions.c tracing/trivial: Fix typos and make an int into a bool 2014-11-20 10:05:36 -05:00
trace_irqsoff.c tracing: Remove unneeded includes of debugfs.h and fs.h 2015-01-22 11:19:48 -05:00
trace_kdb.c KGDB/KDB fixes and cleanups 2015-01-09 20:51:10 -08:00
trace_kprobe.c Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-04-14 14:37:47 -07:00
trace_mmiotrace.c tracing: Do not check return values of trace_seq_p*() for mmio tracer 2014-11-19 15:25:44 -05:00
trace_nop.c tracing: Remove unneeded includes of debugfs.h and fs.h 2015-01-22 11:19:48 -05:00
trace_output.c tracing: Make ftrace_print_array_seq compute buf_len 2015-05-06 23:03:23 -04:00
trace_output.h tracing: Add trace_seq_has_overflowed() and trace_handle_return() 2014-11-19 15:25:39 -05:00
trace_printk.c tracing: Use IS_ERR() check for return value of tracing_init_dentry() 2015-01-22 11:19:49 -05:00
trace_probe.c trace: Don't use __weak in header files 2015-03-25 08:57:23 -04:00
trace_probe.h Some clean ups and small fixes, but the biggest change is the addition 2015-04-14 10:49:03 -07:00
trace_sched_switch.c tracing: Remove unneeded includes of debugfs.h and fs.h 2015-01-22 11:19:48 -05:00
trace_sched_wakeup.c tracing: Remove unneeded includes of debugfs.h and fs.h 2015-01-22 11:19:48 -05:00
trace_selftest_dynamic.c ftrace: Add self-tests for multiple function trace users 2011-05-18 19:24:51 -04:00
trace_selftest.c Seems that Peter Zijlstra added a new check that is making old 2014-10-12 07:28:55 -04:00
trace_seq.c tracing: use %*pb[l] to print bitmaps including cpumasks and nodemasks 2015-02-13 21:21:37 -08:00
trace_stack.c tracing: remove use of seq_printf return value 2015-04-15 16:35:25 -07:00
trace_stat.c tracing: Convert the tracing facility over to use tracefs 2015-02-03 12:48:41 -05:00
trace_stat.h tracing/stat: Add stat_release() callback 2009-07-10 12:14:05 +02:00
trace_syscalls.c perf: Avoid horrible stack usage 2015-01-14 15:11:45 +01:00
trace_uprobe.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
trace.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
trace.h Some clean ups and small fixes, but the biggest change is the addition 2015-04-14 10:49:03 -07:00