Revision 9c29bcd189f4ab1644b7125713602532d0aefdb7 authored by Eric Dumazet on 21 September 2018, 22:27:48 UTC, committed by David S. Miller on 24 September 2018, 04:55:25 UTC
As diagnosed by Song Liu, ndo_poll_controller() can
be very dangerous on loaded hosts, since the cpu
calling ndo_poll_controller() might steal all NAPI
contexts (for all RX/TX queues of the NIC). This capture
can last for unlimited amount of time, since one
cpu is generally not able to drain all the queues under load.

mlx5 uses NAPI for TX completions, so we better let core
networking stack call the napi->poll() to avoid the capture.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 parent a24b66c
Raw File
perf-annotate.txt
perf-annotate(1)
================

NAME
----
perf-annotate - Read perf.data (created by perf record) and display annotated code

SYNOPSIS
--------
[verse]
'perf annotate' [-i <file> | --input=file] [symbol_name]

DESCRIPTION
-----------
This command reads the input file and displays an annotated version of the
code. If the object file has debug symbols then the source code will be
displayed alongside assembly code.

If there is no debug info in the object, then annotated assembly is displayed.

OPTIONS
-------
-i::
--input=<file>::
        Input file name. (default: perf.data unless stdin is a fifo)

-d::
--dsos=<dso[,dso...]>::
        Only consider symbols in these dsos.
-s::
--symbol=<symbol>::
        Symbol to annotate.

-f::
--force::
        Don't do ownership validation.

-v::
--verbose::
        Be more verbose. (Show symbol address, etc)

-q::
--quiet::
	Do not show any message.  (Suppress -v)

-n::
--show-nr-samples::
	Show the number of samples for each symbol

-D::
--dump-raw-trace::
        Dump raw trace in ASCII.

-k::
--vmlinux=<file>::
        vmlinux pathname.

--ignore-vmlinux::
	Ignore vmlinux files.

-m::
--modules::
        Load module symbols. WARNING: use only with -k and LIVE kernel.

-l::
--print-line::
        Print matching source lines (may be slow).

-P::
--full-paths::
        Don't shorten the displayed pathnames.

--stdio:: Use the stdio interface.

--stdio2:: Use the stdio2 interface, non-interactive, uses the TUI formatting.

--stdio-color=<mode>::
	'always', 'never' or 'auto', allowing configuring color output
	via the command line, in addition to via "color.ui" .perfconfig.
	Use '--stdio-color always' to generate color even when redirecting
	to a pipe or file. Using just '--stdio-color' is equivalent to
	using 'always'.

--tui:: Use the TUI interface. Use of --tui requires a tty, if one is not
	present, as when piping to other commands, the stdio interface is
	used. This interfaces starts by centering on the line with more
	samples, TAB/UNTAB cycles through the lines with more samples.

--gtk:: Use the GTK interface.

-C::
--cpu=<cpu>:: Only report samples for the list of CPUs provided. Multiple CPUs can
	be provided as a comma-separated list with no space: 0,1. Ranges of
	CPUs are specified with -: 0-2. Default is to report samples on all
	CPUs.

--asm-raw::
	Show raw instruction encoding of assembly instructions.

--show-total-period:: Show a column with the sum of periods.

--source::
	Interleave source code with assembly code. Enabled by default,
	disable with --no-source.

--symfs=<directory>::
        Look for files with symbols relative to this directory.

-M::
--disassembler-style=:: Set disassembler style for objdump.

--objdump=<path>::
        Path to objdump binary.

--skip-missing::
	Skip symbols that cannot be annotated.

--group::
	Show event group information together

--percent-type::
	Set annotation percent type from following choices:
	  global-period, local-period, global-hits, local-hits

	The local/global keywords set if the percentage is computed
	in the scope of the function (local) or the whole data (global).
	The period/hits keywords set the base the percentage is computed
	on - the samples period or the number of samples (hits).

SEE ALSO
--------
linkperf:perf-record[1], linkperf:perf-report[1]
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