mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-18 00:24:58 +08:00
So at the top we'll have two lines, like this, from 'perf report': # perf report --group --ignore-vmlinux ===================================================================================================== Samples: 46 of events 'cycles', 4000 Hz, Event count (approx.): 5154895 _raw_spin_lock_irqsave /proc/kcore Percent │ nop │ push %rbx 0.00 14.29 0.00 │ pushfq 9.09 0.00 0.00 │ pop %rax 9.09 0.00 20.00 │ nop │ mov %rax,%rbx │ cli 4.55 7.14 0.00 │ nop │ xor %eax,%eax │ mov $0x1,%edx │ lock cmpxchg %edx,(%rdi) 77.27 78.57 70.00 │ test %eax,%eax │ ↓ jne 2b │ mov %rbx,%rax 0.00 0.00 10.00 │ pop %rbx │ ← retq │2b: mov %eax,%esi │ → callq queued_spin_lock_slowpath │ mov %rbx,%rax │ pop %rbx Press 'h' for help on│key bindings ===================================================================================================== 9.09 + 9.09 + 4.55 + 77.27 = 100 14.29 + 7.14 + 78.57 = 100 20 + 70 + 10 = 100 We can do the math by using 't' to toggle from 'percent' to nr ===================================================================================================== Samples: 46 of events 'cycles', 4000 Hz, Event count (approx.): 5154895 _raw_spin_lock_irqsave /proc/kcore Period │ nop │ push %rbx 0 79273 0 │ pushfq 190455 0 0 │ pop %rax 198038 0 3045 │ nop │ mov %rax,%rbx │ cli 217233 32562 0 │ nop │ xor %eax,%eax │ mov $0x1,%edx │ lock cmpxchg %edx,(%rdi) 3421649 979174 28273 │ test %eax,%eax │ ↓ jne 2b │ mov %rbx,%rax 0 0 5193 │ pop %rbx │ ← retq │2b: mov %eax,%esi │ → callq queued_spin_lock_slowpath │ mov %rbx,%rax │ pop %rbx Press 'h' for help on│key bindings ===================================================================================================== 79273 + 190455 + 198038 + 3045 + 217233 + 32562 + 3421649 + 979174 + 28273 + 5193 = 5154895 Or number of samples: ===================================================================================================== ooSamples: 46 of events 'cycles', 4000 Hz, Event count (approx.): 5154895 _raw_spin_lock_irqsave /proc/kcore Samples │ nop │ push %rbx 0 2 0 │ pushfq 2 0 0 │ pop %rax 2 0 2 │ nop │ mov %rax,%rbx │ cli 1 1 0 │ nop │ xor %eax,%eax │ mov $0x1,%edx │ lock cmpxchg %edx,(%rdi) 17 11 7 │ test %eax,%eax │ ↓ jne 2b │ mov %rbx,%rax 0 0 1 │ pop %rbx │ ← retq │2b: mov %eax,%esi │ → callq queued_spin_lock_slowpath │ mov %rbx,%rax │ pop %rbx Press 'h' for help on key bindings ===================================================================================================== 2 + 2 + 2 + 2 + 1 + 1 + 17 + 11 + 7 + 1 = 46 Suggested-by: Martin Liška <mliska@suse.cz> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196935 Link: https://lkml.kernel.org/n/tip-ezccyxld50wtwyt66np6aomo@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
---|---|---|
arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.