Commit 19fb518c2a0c5d88ed22bba7083b7e7bc2a9c231
Committed by
Ingo Molnar
Ingo Molnar
1 parent
50df5d6aea
Exists in
master
and in
4 other branches
latencytop: optimize LT_BACKTRACEDEPTH loops a bit
There is no need to loop any longer when 'same == 0'. Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Showing 1 changed file with 17 additions and 10 deletions Side-by-side Diff
kernel/latencytop.c
| ... | ... | @@ -64,8 +64,8 @@ |
| 64 | 64 | return; |
| 65 | 65 | |
| 66 | 66 | for (i = 0; i < MAXLR; i++) { |
| 67 | - int q; | |
| 68 | - int same = 1; | |
| 67 | + int q, same = 1; | |
| 68 | + | |
| 69 | 69 | /* Nothing stored: */ |
| 70 | 70 | if (!latency_record[i].backtrace[0]) { |
| 71 | 71 | if (firstnonnull > i) |
| 72 | 72 | |
| 73 | 73 | |
| ... | ... | @@ -73,12 +73,15 @@ |
| 73 | 73 | continue; |
| 74 | 74 | } |
| 75 | 75 | for (q = 0 ; q < LT_BACKTRACEDEPTH ; q++) { |
| 76 | - if (latency_record[i].backtrace[q] != | |
| 77 | - lat->backtrace[q]) | |
| 76 | + unsigned long record = lat->backtrace[q]; | |
| 77 | + | |
| 78 | + if (latency_record[i].backtrace[q] != record) { | |
| 78 | 79 | same = 0; |
| 79 | - if (same && lat->backtrace[q] == 0) | |
| 80 | 80 | break; |
| 81 | - if (same && lat->backtrace[q] == ULONG_MAX) | |
| 81 | + } | |
| 82 | + | |
| 83 | + /* 0 and ULONG_MAX entries mean end of backtrace: */ | |
| 84 | + if (record == 0 || record == ULONG_MAX) | |
| 82 | 85 | break; |
| 83 | 86 | } |
| 84 | 87 | if (same) { |
| 85 | 88 | |
| 86 | 89 | |
| 87 | 90 | |
| ... | ... | @@ -143,14 +146,18 @@ |
| 143 | 146 | for (i = 0; i < LT_SAVECOUNT ; i++) { |
| 144 | 147 | struct latency_record *mylat; |
| 145 | 148 | int same = 1; |
| 149 | + | |
| 146 | 150 | mylat = &tsk->latency_record[i]; |
| 147 | 151 | for (q = 0 ; q < LT_BACKTRACEDEPTH ; q++) { |
| 148 | - if (mylat->backtrace[q] != | |
| 149 | - lat.backtrace[q]) | |
| 152 | + unsigned long record = lat.backtrace[q]; | |
| 153 | + | |
| 154 | + if (mylat->backtrace[q] != record) { | |
| 150 | 155 | same = 0; |
| 151 | - if (same && lat.backtrace[q] == 0) | |
| 152 | 156 | break; |
| 153 | - if (same && lat.backtrace[q] == ULONG_MAX) | |
| 157 | + } | |
| 158 | + | |
| 159 | + /* 0 and ULONG_MAX entries mean end of backtrace: */ | |
| 160 | + if (record == 0 || record == ULONG_MAX) | |
| 154 | 161 | break; |
| 155 | 162 | } |
| 156 | 163 | if (same) { |