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tags: much faster, parallel "make tags"

PATCH Superseded Alexey Dobriyan 4 participants 9 messages Apr 14, 2015 – Apr 15, 2015

v1 of 4 Superseded Latest is v4 →

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Alexey Dobriyan

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#0 lore raw

PATCH 1/1 tags: much faster, parallel "make tags"

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)
scripts/tags.sh +32 -2
@@ -152,7 +152,24 @@ dogtags()
 
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	NR_CPUS=1
+	if [ -e /proc/cpuinfo ]; then
+		NR_CPUS=$(grep -e '^processor	: ' /proc/cpuinfo | wc -l)
+	fi
+
+	rm -f .make-tags.src.* .make-tags.*
+
+	all_target_sources >.make-tags.src
+	# seems like Useless Use of cat(1) but not really
+	NR_LINES=$(cat .make-tags.src | wc -l)
+	NR_LINES=$((($NR_LINES + $NR_CPUS - 1) / $NR_CPUS))
+
+	split -a 6 -d -l $NR_LINES .make-tags.src .make-tags.src.
+
+	for i in .make-tags.src.*; do
+		N=$(echo $i | sed -e 's/.*\.//')
+		# -u: don't sort now, sort later
+		cat $i | xargs $1 -a -f .make-tags.$N -u	\
 	-I __initdata,__exitdata,__initconst,			\
 	-I __cpuinitdata,__initdata_memblock			\
 	-I __refdata,__attribute,__maybe_unused,__always_unused \

@@ -211,7 +228,20 @@ exuberant()
 	--regex-c='/DEFINE_PCI_DEVICE_TABLE\((\w*)/\1/v/'		\
 	--regex-c='/(^\s)OFFSET\((\w*)/\2/v/'				\
 	--regex-c='/(^\s)DEFINE\((\w*)/\2/v/'				\
-	--regex-c='/DEFINE_HASHTABLE\((\w*)/\1/v/'
+	--regex-c='/DEFINE_HASHTABLE\((\w*)/\1/v/'			\
+	&
+	done
+	wait
+	rm -f .make-tags.src .make-tags.src.*
+
+	# write header
+	$1 -f tags /dev/null
+	# remove header
+	for i in .make-tags.*; do
+		sed -i -e '/^!/d' $i
+	done
+	sort .make-tags.* >>tags
+	rm -f .make-tags.*
 
 	all_kconfigs | xargs $1 -a                              \
 	--langdef=kconfig --language-force=kconfig              \
#1 lore raw
Quoted 20 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

scripts/tags.sh dogtags() · line 157

Quoted 7 lines
scripts/tags.sh +3 -1
@@ -152,7 +152,24 @@ dogtags()
 
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	NR_CPUS=1
+	if [ -e /proc/cpuinfo ]; then
+		NR_CPUS=$(grep -e '^processor	: ' /proc/cpuinfo | wc -l)

That grep is rather arch-specific. If an arch does not have that string (with an embedded tab), won't NR_CPUS be zero? so at least, set it back to 1?

or (if 'getconf' is installed):
NR_CPUS = getconf _NPROCESSORS_ONLN

Quoted 41 lines
scripts/tags.sh +29 -2
+	fi
+
+	rm -f .make-tags.src.* .make-tags.*
+
+	all_target_sources >.make-tags.src
+	# seems like Useless Use of cat(1) but not really
+	NR_LINES=$(cat .make-tags.src | wc -l)
+	NR_LINES=$((($NR_LINES + $NR_CPUS - 1) / $NR_CPUS))
+
+	split -a 6 -d -l $NR_LINES .make-tags.src .make-tags.src.
+
+	for i in .make-tags.src.*; do
+		N=$(echo $i | sed -e 's/.*\.//')
+		# -u: don't sort now, sort later
+		cat $i | xargs $1 -a -f .make-tags.$N -u	\
 	-I __initdata,__exitdata,__initconst,			\
 	-I __cpuinitdata,__initdata_memblock			\
 	-I __refdata,__attribute,__maybe_unused,__always_unused \

@@ -211,7 +228,20 @@ exuberant()
 	--regex-c='/DEFINE_PCI_DEVICE_TABLE\((\w*)/\1/v/'		\
 	--regex-c='/(^\s)OFFSET\((\w*)/\2/v/'				\
 	--regex-c='/(^\s)DEFINE\((\w*)/\2/v/'				\
-	--regex-c='/DEFINE_HASHTABLE\((\w*)/\1/v/'
+	--regex-c='/DEFINE_HASHTABLE\((\w*)/\1/v/'			\
+	&
+	done
+	wait
+	rm -f .make-tags.src .make-tags.src.*
+
+	# write header
+	$1 -f tags /dev/null
+	# remove header
+	for i in .make-tags.*; do
+		sed -i -e '/^!/d' $i
+	done
+	sort .make-tags.* >>tags
+	rm -f .make-tags.*
 
 	all_kconfigs | xargs $1 -a                              \
 	--langdef=kconfig --language-force=kconfig              \
--
Signature · 1 line
~Randy
#2 lore raw
Quoted 32 lines · Randy Dunlap
Quoted 20 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

scripts/tags.sh dogtags() · line 157

Quoted 7 lines
scripts/tags.sh +3 -1
@@ -152,7 +152,24 @@ dogtags()
 
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	NR_CPUS=1
+	if [ -e /proc/cpuinfo ]; then
+		NR_CPUS=$(grep -e '^processor	: ' /proc/cpuinfo | wc -l)

That grep is rather arch-specific. If an arch does not have that string (with an embedded tab), won't NR_CPUS be zero? so at least, set it back to 1?

Quoted 3 lines

or (if 'getconf' is installed):
NR_CPUS = getconf _NPROCESSORS_ONLN

What is wrong with nproc ?

Guenter

#3 lore raw
Quoted 33 lines · Guenter Roeck
Quoted 32 lines · Randy Dunlap
Quoted 20 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

scripts/tags.sh dogtags() · line 157

Quoted 7 lines
scripts/tags.sh +3 -1
@@ -152,7 +152,24 @@ dogtags()
 
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	NR_CPUS=1
+	if [ -e /proc/cpuinfo ]; then
+		NR_CPUS=$(grep -e '^processor	: ' /proc/cpuinfo | wc -l)

That grep is rather arch-specific. If an arch does not have that string (with an embedded tab), won't NR_CPUS be zero? so at least, set it back to 1?

Quoted 4 lines
Quoted 3 lines

or (if 'getconf' is installed):
NR_CPUS = getconf _NPROCESSORS_ONLN

What is wrong with nproc ?

It's too new. 'getconf _NPROCESSORS_ONLN' has been available since 1996 according to glibc.git.

Michal

#4 lore raw
In reply to Alexey Dobriyan
Quoted 5 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

I want this! :-)

scripts/tags.sh dogtags() · line 164

Quoted 2 lines
scripts/tags.sh +2 -0
+	# seems like Useless Use of cat(1) but not really
+	NR_LINES=$(cat .make-tags.src | wc -l)

wc -l <.make-tags.src

Michal

author
#5 lore raw
Quoted 7 lines · Michal Marek
Quoted 5 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Quoted 7 lines

I want this! :-)

scripts/tags.sh dogtags() · line 164

Quoted 2 lines
scripts/tags.sh +2 -0
+     # seems like Useless Use of cat(1) but not really
+     NR_LINES=$(cat .make-tags.src | wc -l)

wc -l <.make-tags.src

Indeed.

I'll change script to use getconf, since it appears to be standardized.

#6 lore raw
In reply to Alexey Dobriyan
Quoted 20 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

scripts/tags.sh dogtags() · line 158

Quoted 8 lines
scripts/tags.sh +4 -1
@@ -152,7 +152,24 @@ dogtags()
 
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	NR_CPUS=1
+	if [ -e /proc/cpuinfo ]; then
+		NR_CPUS=$(grep -e '^processor	: ' /proc/cpuinfo | wc -l)
+	fi

I wonder if we should rather respect the -j option to make here. But then most people probably won't realize that make tags is parallel and will not use -j when generating tags. So let's leave it as is.

scripts/tags.sh dogtags() · line 160

Quoted 2 lines
scripts/tags.sh +2 -0
+
+	rm -f .make-tags.src.* .make-tags.*

.make-tags.src.* is a subset of .make-tags.*

scripts/tags.sh dogtags() · line 172

Quoted 12 lines
scripts/tags.sh +12 -0
+
+	all_target_sources >.make-tags.src
+	# seems like Useless Use of cat(1) but not really
+	NR_LINES=$(cat .make-tags.src | wc -l)
+	NR_LINES=$((($NR_LINES + $NR_CPUS - 1) / $NR_CPUS))
+
+	split -a 6 -d -l $NR_LINES .make-tags.src .make-tags.src.
+
+	for i in .make-tags.src.*; do
+		N=$(echo $i | sed -e 's/.*\.//')
+		# -u: don't sort now, sort later
+		cat $i | xargs $1 -a -f .make-tags.$N -u	\

xargs <$i $1 ... if you are concerned about uses of cat(1) ;) and the -a option is not necessary since we are creating the tmp files.

scripts/tags.sh exuberant() · line 243

Quoted 7 lines
scripts/tags.sh +7 -0
+	# write header
+	$1 -f tags /dev/null
+	# remove header
+	for i in .make-tags.*; do
+		sed -i -e '/^!/d' $i
+	done
+	sort .make-tags.* >>tags

The hardcoded "tags" filename will break 'make TAGS' when using exuberant ctags via an 'etags' symlink.

Michal

#7 lore raw
Quoted 22 lines · Michal Marek
Quoted 21 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)
scripts/tags.sh +0 -0
@@ -152,7 +152,24 @@ dogtags()
Quoted 11 lines

scripts/tags.sh dogtags() · line 158

Quoted 7 lines
scripts/tags.sh +4 -1
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	NR_CPUS=1
+	if [ -e /proc/cpuinfo ]; then
+		NR_CPUS=$(grep -e '^processor	: ' /proc/cpuinfo | wc -l)
+	fi

I wonder if we should rather respect the -j option to make here. But then most people probably won't realize that make tags is parallel and will not use -j when generating tags. So let's leave it as is.

I meant, leave the concept as is, but fix the detection of the number of cpus.

Quoted 10 lines

scripts/tags.sh exuberant() · line 243

Quoted 7 lines
scripts/tags.sh +7 -0
+	# write header
+	$1 -f tags /dev/null
+	# remove header
+	for i in .make-tags.*; do
+		sed -i -e '/^!/d' $i
+	done
+	sort .make-tags.* >>tags

The hardcoded "tags" filename will break 'make TAGS' when using exuberant ctags via an 'etags' symlink.

Additionally, the TAGS file must not be sorted.

Michal

author
#8 lore raw

PATCH v2 1/1 tags: much faster, parallel "make tags"

In reply to Michal Marek
Quoted 41 lines · Michal Marek
Quoted 20 lines · Alexey Dobriyan

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

scripts/tags.sh dogtags() · line 158

Quoted 8 lines
scripts/tags.sh +4 -1
@@ -152,7 +152,24 @@ dogtags()
 
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	NR_CPUS=1
+	if [ -e /proc/cpuinfo ]; then
+		NR_CPUS=$(grep -e '^processor	: ' /proc/cpuinfo | wc -l)
+	fi

I wonder if we should rather respect the -j option to make here. But then most people probably won't realize that make tags is parallel and will not use -j when generating tags. So let's leave it as is.

scripts/tags.sh dogtags() · line 160

Quoted 2 lines
scripts/tags.sh +2 -0
+
+	rm -f .make-tags.src.* .make-tags.*

.make-tags.src.* is a subset of .make-tags.*

Quoted 15 lines

scripts/tags.sh dogtags() · line 172

Quoted 12 lines
scripts/tags.sh +12 -0
+
+	all_target_sources >.make-tags.src
+	# seems like Useless Use of cat(1) but not really
+	NR_LINES=$(cat .make-tags.src | wc -l)
+	NR_LINES=$((($NR_LINES + $NR_CPUS - 1) / $NR_CPUS))
+
+	split -a 6 -d -l $NR_LINES .make-tags.src .make-tags.src.
+
+	for i in .make-tags.src.*; do
+		N=$(echo $i | sed -e 's/.*\.//')
+		# -u: don't sort now, sort later
+		cat $i | xargs $1 -a -f .make-tags.$N -u	\

xargs <$i $1 ... if you are concerned about uses of cat(1) ;) and the -a option is not necessary since we are creating the tmp files.

If "-a" is omitted, tags file becomes broken for some reason, e. g. "file_operations" isn't there anymore.

Quoted 10 lines

scripts/tags.sh dogtags()

Quoted 7 lines
scripts/tags.sh +7 -0
+	# write header
+	$1 -f tags /dev/null
+	# remove header
+	for i in .make-tags.*; do
+		sed -i -e '/^!/d' $i
+	done
+	sort .make-tags.* >>tags

The hardcoded "tags" filename will break 'make TAGS' when using exuberant ctags via an 'etags' symlink.

I don't understand why would you fake etags with ctags. It would go via "emacs" path, which is not changed.
----------------------------------------------------------------------
[PATCH] tags: much faster, parallel "make tags"

ctags is single-threaded program. Split list of files to be tagged into equal parts, 1 part for each CPU and then merge the results.

Speedup on one 2-way box I have is ~143 s => ~99 s (-31%). On another 4-way box: ~120 s => ~65 s (-46%!).

Resulting "tags" files aren't byte-for-byte identical because ctags program numbers anon struct and enum declarations with "__anonNNN" symbols. If those lines are removed, "tags" file becomes byte-for-byte identical with those generated with current code.

Signed-off-by Alexey Dobriyan <[email protected]>

---

 scripts/tags.sh |   36 +++++++++++++++++++++++++++++++-----
 1 file changed, 31 insertions(+), 5 deletions(-)
scripts/tags.sh +31 -5
@@ -152,7 +152,19 @@ dogtags()
 
 exuberant()
 {
-	all_target_sources | xargs $1 -a                        \
+	rm -f .make-tags.*
+
+	all_target_sources >.make-tags.src
+	NR_CPUS=$(getconf _NPROCESSORS_ONLN 2>/dev/null || echo 1)
+	NR_LINES=$(wc -l <.make-tags.src)
+	NR_LINES=$((($NR_LINES + $NR_CPUS - 1) / $NR_CPUS))
+
+	split -a 6 -d -l $NR_LINES .make-tags.src .make-tags.src.
+
+	for i in .make-tags.src.*; do
+		N=$(echo $i | sed -e 's/.*\.//')
+		# -u: don't sort now, sort later
+		xargs <$i $1 -a -f .make-tags.$N -u		\
 	-I __initdata,__exitdata,__initconst,			\
 	-I __cpuinitdata,__initdata_memblock			\
 	-I __refdata,__attribute,__maybe_unused,__always_unused \

@@ -211,7 +223,21 @@ exuberant()
 	--regex-c='/DEFINE_PCI_DEVICE_TABLE\((\w*)/\1/v/'		\
 	--regex-c='/(^\s)OFFSET\((\w*)/\2/v/'				\
 	--regex-c='/(^\s)DEFINE\((\w*)/\2/v/'				\
-	--regex-c='/DEFINE_HASHTABLE\((\w*)/\1/v/'
+	--regex-c='/DEFINE_HASHTABLE\((\w*)/\1/v/'			\
+	&
+	done
+	wait
+	rm -f .make-tags.src .make-tags.src.*
+
+	# write header
+	$1 -f $2 /dev/null
+	# remove headers
+	for i in .make-tags.*; do
+		sed -i -e '/^!/d' $i &
+	done
+	wait
+	sort .make-tags.* >>$2
+	rm -f .make-tags.*
 
 	all_kconfigs | xargs $1 -a                              \
 	--langdef=kconfig --language-force=kconfig              \

@@ -276,7 +302,7 @@ emacs()
 xtags()
 {
 	if $1 --version 2>&1 | grep -iq exuberant; then
-		exuberant $1
+		exuberant $1 $2
 	elif $1 --version 2>&1 | grep -iq emacs; then
 		emacs $1
 	else

@@ -322,13 +348,13 @@ case "$1" in
 
 	"tags")
 		rm -f tags
-		xtags ctags
+		xtags ctags tags
 		remove_structs=y
 		;;
 
 	"TAGS")
 		rm -f TAGS
-		xtags etags
+		xtags etags TAGS
 		remove_structs=y
 		;;
 esac