The kernel has plenty of ternary operators to choose between constant strings, such as condition ? "yes" : "no", as well as value == 1 ? "" : "s": $ git grep '? "yes" : "no"' | wc -l 258 $ git grep '? "on" : "off"' | wc -l 204 $ git grep '? "enabled" : "disabled"' | wc -l 196 $ git grep '? "" : "s"' | wc -l 25 Additionally, there are some occurences of the same in reverse order, split to multiple lines, or otherwise not caught by the simple grep. Add helpers to return the constant strings. Remove existing equivalent and conflicting functions in i915, cxgb4, and USB core. Further conversion can be done incrementally. While the main goal here is to abstract recurring patterns, and slightly clean up the code base by not open coding the ternary operators, there are also some space savings to be had via better string constant pooling. Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx Cc: Vishal Kulkarni <vishal@xxxxxxxxxxx> Cc: netdev@xxxxxxxxxxxxxxx Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: linux-usb@xxxxxxxxxxxxxxx Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: Julia Lawall <julia.lawall@xxxxxxx> Cc: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> # v1 Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> --- v2: add string-choice.[ch] to not clutter kernel.h and to actually save space on string constants. Example of further cleanup possibilities are at [1], to be done incrementally afterwards. [1] http://lore.kernel.org/r/20190903133731.2094-2-jani.nikula@xxxxxxxxx --- drivers/gpu/drm/i915/i915_utils.h | 16 +--------- .../ethernet/chelsio/cxgb4/cxgb4_debugfs.c | 12 +------ drivers/usb/core/config.c | 6 +--- drivers/usb/core/generic.c | 6 +--- include/linux/kernel.h | 1 + include/linux/string-choice.h | 16 ++++++++++ lib/Makefile | 2 +- lib/string-choice.c | 31 +++++++++++++++++++ 8 files changed, 53 insertions(+), 37 deletions(-) create mode 100644 include/linux/string-choice.h create mode 100644 lib/string-choice.c diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h index 562f756da421..794f02a90efe 100644 --- a/drivers/gpu/drm/i915/i915_utils.h +++ b/drivers/gpu/drm/i915/i915_utils.h @@ -28,6 +28,7 @@ #include <linux/list.h> #include <linux/overflow.h> #include <linux/sched.h> +#include <linux/string-choice.h> #include <linux/types.h> #include <linux/workqueue.h> @@ -395,21 +396,6 @@ wait_remaining_ms_from_jiffies(unsigned long timestamp_jiffies, int to_wait_ms) #define MBps(x) KBps(1000 * (x)) #define GBps(x) ((u64)1000 * MBps((x))) -static inline const char *yesno(bool v) -{ - return v ? "yes" : "no"; -} - -static inline const char *onoff(bool v) -{ - return v ? "on" : "off"; -} - -static inline const char *enableddisabled(bool v) -{ - return v ? "enabled" : "disabled"; -} - static inline void add_taint_for_CI(unsigned int taint) { /* diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c index ae6a47dd7dc9..d9123dae1d00 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c +++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_debugfs.c @@ -35,6 +35,7 @@ #include <linux/seq_file.h> #include <linux/debugfs.h> #include <linux/string_helpers.h> +#include <linux/string-choice.h> #include <linux/sort.h> #include <linux/ctype.h> @@ -2023,17 +2024,6 @@ static const struct file_operations rss_debugfs_fops = { /* RSS Configuration. */ -/* Small utility function to return the strings "yes" or "no" if the supplied - * argument is non-zero. - */ -static const char *yesno(int x) -{ - static const char *yes = "yes"; - static const char *no = "no"; - - return x ? yes : no; -} - static int rss_config_show(struct seq_file *seq, void *v) { struct adapter *adapter = seq->private; diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c index 151a74a54386..52cee9067eb4 100644 --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -10,6 +10,7 @@ #include <linux/module.h> #include <linux/slab.h> #include <linux/device.h> +#include <linux/string-choice.h> #include <asm/byteorder.h> #include "usb.h" @@ -19,11 +20,6 @@ #define USB_MAXCONFIG 8 /* Arbitrary limit */ -static inline const char *plural(int n) -{ - return (n == 1 ? "" : "s"); -} - static int find_next_descriptor(unsigned char *buffer, int size, int dt1, int dt2, int *num_skipped) { diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c index 38f8b3e31762..a784a09794d6 100644 --- a/drivers/usb/core/generic.c +++ b/drivers/usb/core/generic.c @@ -21,14 +21,10 @@ #include <linux/usb.h> #include <linux/usb/hcd.h> +#include <linux/string-choice.h> #include <uapi/linux/usb/audio.h> #include "usb.h" -static inline const char *plural(int n) -{ - return (n == 1 ? "" : "s"); -} - static int is_rndis(struct usb_interface_descriptor *desc) { return desc->bInterfaceClass == USB_CLASS_COMM diff --git a/include/linux/kernel.h b/include/linux/kernel.h index d83d403dac2e..91ace0e6ec1d 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -1029,4 +1029,5 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } /* OTHER_WRITABLE? Generally considered a bad idea. */ \ BUILD_BUG_ON_ZERO((perms) & 2) + \ (perms)) + #endif diff --git a/include/linux/string-choice.h b/include/linux/string-choice.h new file mode 100644 index 000000000000..1583b909e2c9 --- /dev/null +++ b/include/linux/string-choice.h @@ -0,0 +1,16 @@ +/* SPDX-License-Identifier: MIT */ +/* + * Copyright © 2019 Intel Corporation + */ + +#ifndef __STRING_CHOICE_H__ +#define __STRING_CHOICE_H__ + +#include <linux/types.h> + +const char *yesno(bool v); +const char *onoff(bool v); +const char *enableddisabled(bool v); +const char *plural(long v); + +#endif /* __STRING_CHOICE_H__ */ diff --git a/lib/Makefile b/lib/Makefile index c5892807e06f..30247fbf1afe 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -46,7 +46,7 @@ obj-y += bcd.o sort.o parser.o debug_locks.o random32.o \ bsearch.o find_bit.o llist.o memweight.o kfifo.o \ percpu-refcount.o rhashtable.o \ once.o refcount.o usercopy.o errseq.o bucket_locks.o \ - generic-radix-tree.o + generic-radix-tree.o string-choice.o obj-$(CONFIG_STRING_SELFTEST) += test_string.o obj-y += string_helpers.o obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o diff --git a/lib/string-choice.c b/lib/string-choice.c new file mode 100644 index 000000000000..d20680a6603e --- /dev/null +++ b/lib/string-choice.c @@ -0,0 +1,31 @@ +// SPDX-License-Identifier: MIT +/* + * Copyright © 2019 Intel Corporation + */ + +#include <linux/export.h> +#include <linux/string-choice.h> + +const char *yesno(bool v) +{ + return v ? "yes" : "no"; +} +EXPORT_SYMBOL(yesno); + +const char *onoff(bool v) +{ + return v ? "on" : "off"; +} +EXPORT_SYMBOL(onoff); + +const char *enableddisabled(bool v) +{ + return v ? "enabled" : "disabled"; +} +EXPORT_SYMBOL(enableddisabled); + +const char *plural(long v) +{ + return v == 1 ? "" : "s"; +} +EXPORT_SYMBOL(plural); -- 2.20.1
