Revision 8b2180b3bf0338625cab07da6543acb436df9c40 authored by Dave Chinner on 16 August 2016, 22:31:33 UTC, committed by Dave Chinner on 16 August 2016, 22:31:33 UTC
When we do DAX IO, we try to invalidate the entire page cache held on the file. This is incorrect as it will trash the entire mapping tree that now tracks dirty state in exceptional entries in the radix tree slots. What we are trying to do is remove cached pages (e.g from reads into holes) that sit in the radix tree over the range we are about to write to. Hence we should just limit the invalidation to the range we are about to overwrite. Reported-by: Jan Kara <jack@suse.cz> Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Chinner <david@fromorbit.com>
1 parent 0af32fb
decode_stacktrace.sh
#!/bin/bash
# (c) 2014, Sasha Levin <sasha.levin@oracle.com>
#set -x
if [[ $# < 2 ]]; then
echo "Usage:"
echo " $0 [vmlinux] [base path] [modules path]"
exit 1
fi
vmlinux=$1
basepath=$2
modpath=$3
declare -A cache
declare -A modcache
parse_symbol() {
# The structure of symbol at this point is:
# ([name]+[offset]/[total length])
#
# For example:
# do_basic_setup+0x9c/0xbf
if [[ $module == "" ]] ; then
local objfile=$vmlinux
elif [[ "${modcache[$module]+isset}" == "isset" ]]; then
local objfile=${modcache[$module]}
else
[[ $modpath == "" ]] && return
local objfile=$(find "$modpath" -name $module.ko -print -quit)
[[ $objfile == "" ]] && return
modcache[$module]=$objfile
fi
# Remove the englobing parenthesis
symbol=${symbol#\(}
symbol=${symbol%\)}
# Strip the symbol name so that we could look it up
local name=${symbol%+*}
# Use 'nm vmlinux' to figure out the base address of said symbol.
# It's actually faster to call it every time than to load it
# all into bash.
if [[ "${cache[$module,$name]+isset}" == "isset" ]]; then
local base_addr=${cache[$module,$name]}
else
local base_addr=$(nm "$objfile" | grep -i ' t ' | awk "/ $name\$/ {print \$1}" | head -n1)
cache[$module,$name]="$base_addr"
fi
# Let's start doing the math to get the exact address into the
# symbol. First, strip out the symbol total length.
local expr=${symbol%/*}
# Now, replace the symbol name with the base address we found
# before.
expr=${expr/$name/0x$base_addr}
# Evaluate it to find the actual address
expr=$((expr))
local address=$(printf "%x\n" "$expr")
# Pass it to addr2line to get filename and line number
# Could get more than one result
if [[ "${cache[$module,$address]+isset}" == "isset" ]]; then
local code=${cache[$module,$address]}
else
local code=$(addr2line -i -e "$objfile" "$address")
cache[$module,$address]=$code
fi
# addr2line doesn't return a proper error code if it fails, so
# we detect it using the value it prints so that we could preserve
# the offset/size into the function and bail out
if [[ $code == "??:0" ]]; then
return
fi
# Strip out the base of the path
code=${code//$basepath/""}
# In the case of inlines, move everything to same line
code=${code//$'\n'/' '}
# Replace old address with pretty line numbers
symbol="$name ($code)"
}
decode_code() {
local scripts=`dirname "${BASH_SOURCE[0]}"`
echo "$1" | $scripts/decodecode
}
handle_line() {
local words
# Tokenize
read -a words <<<"$1"
# Remove hex numbers. Do it ourselves until it happens in the
# kernel
# We need to know the index of the last element before we
# remove elements because arrays are sparse
local last=$(( ${#words[@]} - 1 ))
for i in "${!words[@]}"; do
# Remove the address
if [[ ${words[$i]} =~ \[\<([^]]+)\>\] ]]; then
unset words[$i]
fi
# Format timestamps with tabs
if [[ ${words[$i]} == \[ && ${words[$i+1]} == *\] ]]; then
unset words[$i]
words[$i+1]=$(printf "[%13s\n" "${words[$i+1]}")
fi
done
if [[ ${words[$last]} =~ \[([^]]+)\] ]]; then
module=${words[$last]}
module=${module#\[}
module=${module%\]}
symbol=${words[$last-1]}
unset words[$last-1]
else
# The symbol is the last element, process it
symbol=${words[$last]}
module=
fi
unset words[$last]
parse_symbol # modifies $symbol
# Add up the line number to the symbol
echo "${words[@]}" "$symbol $module"
}
while read line; do
# Let's see if we have an address in the line
if [[ $line =~ \[\<([^]]+)\>\] ]]; then
# Translate address to line numbers
handle_line "$line"
# Is it a code line?
elif [[ $line == *Code:* ]]; then
decode_code "$line"
else
# Nothing special in this line, show it as is
echo "$line"
fi
done
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