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path: root/kernel/trace/trace_branch.c
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2008-12-03ftrace: replace raw_local_irq_save with local_irq_saveSteven Rostedt
Impact: fix for lockdep and ftrace The raw_local_irq_save/restore confuses lockdep. This patch converts them to the local_irq_save/restore variants. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-29tracing/branch-tracer: include missing irqflags.hFrederic Weisbecker
Impact: fix build error on branch tracer This should fix a build error reported on alpha in linux-next: CC kernel/trace/trace_branch.o kernel/trace/trace_branch.c: In function 'probe_likely_condition': kernel/trace/trace_branch.c:44: error: implicit declaration of function 'raw_local_irq_save' kernel/trace/trace_branch.c:76: error: implicit declaration of function 'raw_local_irq_restore' Unfortunately, I can't test it since I don't have any Alpha build environment. Reported-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-23trace: fix compiler warning in branch profilerSteven Rostedt
Impact: fix compiler warning The ftrace_pointers used in the branch profiler are constant values. They should never change. But the compiler complains when they are passed into the debugfs_create_file as a data pointer, because the function discards the qualifier. This patch typecasts the parameter to debugfs_create_file back to a void pointer. To remind the callbacks that they are pointing to a constant value, I also modified the callback local pointers to be const struct ftrace_pointer * as well. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-23trace: profile all if conditionalsSteven Rostedt
Impact: feature to profile if statements This patch adds a branch profiler for all if () statements. The results will be found in: /debugfs/tracing/profile_branch For example: miss hit % Function File Line ------- --------- - -------- ---- ---- 0 1 100 x86_64_start_reservations head64.c 127 0 1 100 copy_bootdata head64.c 69 1 0 0 x86_64_start_kernel head64.c 111 32 0 0 set_intr_gate desc.h 319 1 0 0 reserve_ebda_region head.c 51 1 0 0 reserve_ebda_region head.c 47 0 1 100 reserve_ebda_region head.c 42 0 0 X maxcpus main.c 165 Miss means the branch was not taken. Hit means the branch was taken. The percent is the percentage the branch was taken. This adds a significant amount of overhead and should only be used by those analyzing their system. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-23trace: branch profiling should not print percent without dataSteven Rostedt
Impact: cleanup on output of branch profiler When a branch has not been taken, it does not make sense to show a percentage incorrect or hit. This patch changes the behaviour to print out a 'X' when the branch has not been executed yet. For example: correct incorrect % Function File Line ------- --------- - -------- ---- ---- 2096 0 0 do_arch_prctl process_64.c 832 0 0 X do_arch_prctl process_64.c 804 2604 0 0 IS_ERR err.h 34 130228 5765 4 __switch_to process_64.c 673 0 0 X enable_TSC process_64.c 448 0 0 X disable_TSC process_64.c 431 Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-23trace: consolidate unlikely and likely profilerSteven Rostedt
Impact: clean up to make one profiler of like and unlikely tracer The likely and unlikely profiler prints out the file and line numbers of the annotated branches that it is profiling. It shows the number of times it was correct or incorrect in its guess. Having two different files or sections for that matter to tell us if it was a likely or unlikely is pretty pointless. We really only care if it was correct or not. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-17Merge branches 'tracing/branch-tracer', 'tracing/ftrace', ↵Ingo Molnar
'tracing/function-return-tracer', 'tracing/tracepoints' and 'tracing/urgent' into tracing/core
2008-11-16tracing/branch-tracer: fix a trace recursion on branch tracerFrederic Weisbecker
Impact: fix crash when enabling the branch-tracer When the branch tracer inserts an event through probe_likely_condition(), it calls local_irq_save() and then results in a trace recursion. local_irq_save() -> trace_hardirqs_off() -> trace_hardirqs_off_caller() -> unlikely() The trace_branch.c file is protected by DISABLE_BRANCH_PROFILING but that doesn't prevent from external call to functions that use unlikely(). My box crashed each time I tried to set this tracer (sudden and hard reboot). Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-16tracing/ftrace: change the type of the init() callbackFrederic Weisbecker
Impact: extend the ->init() method with the ability to fail This bring a way to know if the initialization of a tracer successed. A tracer must return 0 on success and a traditional error (ie: -ENOMEM) if it fails. If a tracer fails to init, it is free to print a detailed warn. The tracing api will not and switch to a new tracer will just return the error from the init callback. Note: this will be used for the return tracer. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-12ftrace: rename trace_unlikely.c fileSteven Rostedt
Impact: File name change of trace_unlikely.c The "unlikely" name for the tracer is quite ugly. We renamed all the parts of it to "branch" and now it is time to rename the file too. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>