Commit 39cf650d authored by Brian Johannesmeyer's avatar Brian Johannesmeyer Committed by Josh Poimboeuf
Browse files

scripts/faddr2line: Reduce number of readelf calls to three 



Rather than calling readelf several times for each invocation of
__faddr2line, call readelf only three times at the beginning, and save its
result for future use.

Signed-off-by: default avatarBrian Johannesmeyer <bjohannesmeyer@gmail.com>
Link: https://lore.kernel.org/r/20240415145538.1938745-2-bjohannesmeyer@gmail.com


Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@kernel.org>
parent 22a40d14

scripts/faddr2line

+17 −9
Original line number Diff line number Diff line
@@ -87,7 +87,7 @@ command -v ${ADDR2LINE} >/dev/null 2>&1 || die "${ADDR2LINE} isn't installed" 
find_dir_prefix() {

	local objfile=$1



	local start_kernel_addr=$(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' |

	local start_kernel_addr=$(echo "${ELF_SYMS}" | sed 's/\[.*\]//' |

		${AWK} '$8 == "start_kernel" {printf "0x%s", $2}')

	[[ -z $start_kernel_addr ]] && return
@@ -103,6 +103,14 @@ find_dir_prefix() { 
	return 0

}



run_readelf() {

	local objfile=$1



	ELF_FILEHEADER=$(${READELF} --file-header $objfile)

	ELF_SECHEADERS=$(${READELF} --section-headers --wide $objfile)

	ELF_SYMS=$(${READELF} --symbols --wide $objfile)

}



__faddr2line() {

	local objfile=$1

	local func_addr=$2
@@ -125,7 +133,7 @@ __faddr2line() { 


	# vmlinux uses absolute addresses in the section table rather than

	# section offsets.

	local file_type=$(${READELF} --file-header $objfile |

	local file_type=$(echo "${ELF_FILEHEADER}" |

		${AWK} '$1 == "Type:" { print $2; exit }')

	if [[ $file_type = "EXEC" ]] || [[ $file_type == "DYN" ]]; then

		is_vmlinux=1
@@ -143,8 +151,7 @@ __faddr2line() { 
		local sec_name



		# Get the section size:

		sec_size=$(${READELF} --section-headers --wide $objfile |

			sed 's/\[ /\[/' |

		sec_size=$(echo "${ELF_SECHEADERS}" | sed 's/\[ /\[/' |

			${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print "0x" $6; exit }')



		if [[ -z $sec_size ]]; then
@@ -154,8 +161,7 @@ __faddr2line() { 
		fi



		# Get the section name:

		sec_name=$(${READELF} --section-headers --wide $objfile |

			sed 's/\[ /\[/' |

		sec_name=$(echo "${ELF_SECHEADERS}" | sed 's/\[ /\[/' |

			${AWK} -v sec=$sym_sec '$1 == "[" sec "]" { print $2; exit }')



		if [[ -z $sec_name ]]; then
@@ -197,7 +203,7 @@ __faddr2line() { 
				found=2

				break

			fi

		done < <(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' | ${AWK} -v sec=$sym_sec '$7 == sec' | sort --key=2)

		done < <(echo "${ELF_SYMS}" | sed 's/\[.*\]//' | ${AWK} -v sec=$sym_sec '$7 == sec' | sort --key=2)



		if [[ $found = 0 ]]; then

			warn "can't find symbol: sym_name: $sym_name sym_sec: $sym_sec sym_addr: $sym_addr sym_elf_size: $sym_elf_size"
@@ -278,7 +284,7 @@ __faddr2line() { 


		DONE=1



	done < <(${READELF} --symbols --wide $objfile | sed 's/\[.*\]//' | ${AWK} -v fn=$sym_name '$8 == fn')

	done < <(echo "${ELF_SYMS}" | sed 's/\[.*\]//' | ${AWK} -v fn=$sym_name '$8 == fn')

}



[[ $# -lt 2 ]] && usage
@@ -291,7 +297,9 @@ LIST=0 
[[ ! -f $objfile ]] && die "can't find objfile $objfile"

shift



${READELF} --section-headers --wide $objfile | ${GREP} -q '\.debug_info' || die "CONFIG_DEBUG_INFO not enabled"

run_readelf $objfile



echo "${ELF_SECHEADERS}" | ${GREP} -q '\.debug_info' || die "CONFIG_DEBUG_INFO not enabled"



DIR_PREFIX=supercalifragilisticexpialidocious

find_dir_prefix $objfile