linux/scripts/kconfig/expr.h

332 lines
9.6 KiB
C
Raw Normal View History

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
*/
#ifndef EXPR_H
#define EXPR_H
#ifdef __cplusplus
extern "C" {
#endif
#include <assert.h>
#include <stdio.h>
#include "list.h"
#ifndef __cplusplus
#include <stdbool.h>
#endif
struct file {
struct file *next;
struct file *parent;
const char *name;
int lineno;
};
typedef enum tristate {
no, mod, yes
} tristate;
enum expr_type {
E_NONE, E_OR, E_AND, E_NOT,
E_EQUAL, E_UNEQUAL, E_LTH, E_LEQ, E_GTH, E_GEQ,
E_LIST, E_SYMBOL, E_RANGE
};
union expr_data {
struct expr *expr;
struct symbol *sym;
};
struct expr {
enum expr_type type;
union expr_data left, right;
};
#define EXPR_OR(dep1, dep2) (((dep1)>(dep2))?(dep1):(dep2))
#define EXPR_AND(dep1, dep2) (((dep1)<(dep2))?(dep1):(dep2))
#define EXPR_NOT(dep) (2-(dep))
#define expr_list_for_each_sym(l, e, s) \
for (e = (l); e && (s = e->right.sym); e = e->left.expr)
struct expr_value {
struct expr *expr;
tristate tri;
};
struct symbol_value {
void *val;
tristate tri;
};
enum symbol_type {
S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING
};
/* enum values are used as index to symbol.def[] */
enum {
S_DEF_USER, /* main user value */
S_DEF_AUTO, /* values read from auto.conf */
S_DEF_DEF3, /* Reserved for UI usage */
S_DEF_DEF4, /* Reserved for UI usage */
S_DEF_COUNT
};
/*
* Represents a configuration symbol.
*
* Choices are represented as a special kind of symbol and have the
* SYMBOL_CHOICE bit set in 'flags'.
*/
struct symbol {
/* The next symbol in the same bucket in the symbol hash table */
struct symbol *next;
/* The name of the symbol, e.g. "FOO" for 'config FOO' */
char *name;
/* S_BOOLEAN, S_TRISTATE, ... */
enum symbol_type type;
/*
* The calculated value of the symbol. The SYMBOL_VALID bit is set in
* 'flags' when this is up to date. Note that this value might differ
* from the user value set in e.g. a .config file, due to visibility.
*/
struct symbol_value curr;
/*
* Values for the symbol provided from outside. def[S_DEF_USER] holds
* the .config value.
*/
struct symbol_value def[S_DEF_COUNT];
/*
* An upper bound on the tristate value the user can set for the symbol
* if it is a boolean or tristate. Calculated from prompt dependencies,
* which also inherit dependencies from enclosing menus, choices, and
* ifs. If 'n', the user value will be ignored.
*
* Symbols lacking prompts always have visibility 'n'.
*/
tristate visible;
/* SYMBOL_* flags */
int flags;
/* List of properties. See prop_type. */
struct property *prop;
/* Dependencies from enclosing menus, choices, and ifs */
struct expr_value dir_dep;
/* Reverse dependencies through being selected by other symbols */
struct expr_value rev_dep;
/*
* "Weak" reverse dependencies through being implied by other symbols
*/
Kconfig: Introduce the "imply" keyword The "imply" keyword is a weak version of "select" where the target config symbol can still be turned off, avoiding those pitfalls that come with the "select" keyword. This is useful e.g. with multiple drivers that want to indicate their ability to hook into a secondary subsystem while allowing the user to configure that subsystem out without also having to unset these drivers. Currently, the same effect can almost be achieved with: config DRIVER_A tristate config DRIVER_B tristate config DRIVER_C tristate config DRIVER_D tristate [...] config SUBSYSTEM_X tristate default DRIVER_A || DRIVER_B || DRIVER_C || DRIVER_D || [...] This is unwieldy to maintain especially with a large number of drivers. Furthermore, there is no easy way to restrict the choice for SUBSYSTEM_X to y or n, excluding m, when some drivers are built-in. The "select" keyword allows for excluding m, but it excludes n as well. Hence this "imply" keyword. The above becomes: config DRIVER_A tristate imply SUBSYSTEM_X config DRIVER_B tristate imply SUBSYSTEM_X [...] config SUBSYSTEM_X tristate This is much cleaner, and way more flexible than "select". SUBSYSTEM_X can still be configured out, and it can be set as a module when none of the drivers are configured in or all of them are modular. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: linux-kbuild@vger.kernel.org Cc: netdev@vger.kernel.org Cc: Michal Marek <mmarek@suse.com> Cc: Edward Cree <ecree@solarflare.com> Link: http://lkml.kernel.org/r/1478841010-28605-2-git-send-email-nicolas.pitre@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-11 13:10:05 +08:00
struct expr_value implied;
};
#define for_all_symbols(i, sym) for (i = 0; i < SYMBOL_HASHSIZE; i++) for (sym = symbol_hash[i]; sym; sym = sym->next)
#define SYMBOL_CONST 0x0001 /* symbol is const */
#define SYMBOL_CHECK 0x0008 /* used during dependency checking */
#define SYMBOL_CHOICE 0x0010 /* start of a choice block (null name) */
#define SYMBOL_CHOICEVAL 0x0020 /* used as a value in a choice block */
#define SYMBOL_VALID 0x0080 /* set when symbol.curr is calculated */
#define SYMBOL_OPTIONAL 0x0100 /* choice is optional - values can be 'n' */
#define SYMBOL_WRITE 0x0200 /* write symbol to file (KCONFIG_CONFIG) */
#define SYMBOL_CHANGED 0x0400 /* ? */
#define SYMBOL_NO_WRITE 0x1000 /* Symbol for internal use only; it will not be written */
#define SYMBOL_CHECKED 0x2000 /* used during dependency checking */
#define SYMBOL_WARNED 0x8000 /* warning has been issued */
/* Set when symbol.def[] is used */
#define SYMBOL_DEF 0x10000 /* First bit of SYMBOL_DEF */
#define SYMBOL_DEF_USER 0x10000 /* symbol.def[S_DEF_USER] is valid */
#define SYMBOL_DEF_AUTO 0x20000 /* symbol.def[S_DEF_AUTO] is valid */
#define SYMBOL_DEF3 0x40000 /* symbol.def[S_DEF_3] is valid */
#define SYMBOL_DEF4 0x80000 /* symbol.def[S_DEF_4] is valid */
kconfig: Fix defconfig when one choice menu selects options that another choice menu depends on The defconfig and Kconfig combination below, which is based on 3.10-rc4 Kconfigs, resulted in several options getting set to "m" instead of "y". defconfig.choice: ---8<--- CONFIG_MODULES=y CONFIG_USB_ZERO=y ---8<--- Kconfig.choice: ---8<--- menuconfig MODULES bool "Enable loadable module support" config CONFIGFS_FS tristate "Userspace-driven configuration filesystem" config OCFS2_FS tristate "OCFS2 file system support" depends on CONFIGFS_FS select CRC32 config USB_LIBCOMPOSITE tristate select CONFIGFS_FS choice tristate "USB Gadget Drivers" default USB_ETH config USB_ZERO tristate "Gadget Zero (DEVELOPMENT)" select USB_LIBCOMPOSITE config USB_ETH tristate "Ethernet Gadget (with CDC Ethernet support)" select USB_LIBCOMPOSITE endchoice config CRC32 tristate "CRC32/CRC32c functions" default y choice prompt "CRC32 implementation" depends on CRC32 default CRC32_SLICEBY8 config CRC32_SLICEBY8 bool "Slice by 8 bytes" endchoice ---8<--- $ scripts/kconfig/conf --defconfig=defconfig.choice Kconfig.choice would result in: .config: ---8<--- CONFIG_MODULES=y CONFIG_CONFIGFS_FS=m CONFIG_USB_LIBCOMPOSITE=m CONFIG_USB_ZERO=m CONFIG_CRC32=y CONFIG_CRC32_SLICEBY8=y ---8<--- when the expected result would be: .config: ---8<--- CONFIG_MODULES=y CONFIG_CONFIGFS_FS=y CONFIG_USB_LIBCOMPOSITE=y CONFIG_USB_ZERO=y CONFIG_CRC32=y CONFIG_CRC32_SLICEBY8=y ---8<--- Signed-off-by: Arve Hjønnevåg <arve@android.com> [yann.morin.1998@free.fr: add the resulting .config to commit log, remove unneeded USB_GADGET from the defconfig] Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr> Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
2013-06-07 11:37:00 +08:00
/* choice values need to be set before calculating this symbol value */
#define SYMBOL_NEED_SET_CHOICE_VALUES 0x100000
/* Set symbol to y if allnoconfig; used for symbols that hide others */
#define SYMBOL_ALLNOCONFIG_Y 0x200000
#define SYMBOL_MAXLENGTH 256
Improve kconfig symbol hashing While looking for something else I noticed that the symbol hash function used by kconfig is quite poor. It doesn't use any of the standard hash techniques but simply adds up the string and then uses power of two masking, which is both known to perform poorly. The current x86 kconfig has over 7000 symbols. When I instrumented it showed that the minimum hash chain length was 16 and a significant number of them was over 30. It didn't help that the hash table size was only 256 buckets. This patch increases the hash table size to a larger prime and switches to a FNV32 hash. I played around with a couple of hash functions, but that one seemed to perform best with reasonable hash table sizes. Increasing the hash table size even further didn't seem like a good idea, because there are a couple of global walks which walk the complete hash table. I also moved the unnamed bucket to 0. It's still the longest of all the buckets (44 entries), but hopefully it's not often hit except for the global walk which doesn't care. The result is a much nicer distribution: (first column bucket length, second number of buckets with that length) 1: 3505 2: 1236 3: 294 4: 52 5: 3 47: 1 <--- this is the unnamed symbols bucket There are still some 5+ buckets, but increasing the hash table even more would be likely not worth it. This also cleans up the code slightly by removing hard coded magic numbers. I didn't notice a big performance difference either way on my Nehalem system, but I presume it'll help somewhat on slower systems. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Michal Marek <mmarek@suse.cz>
2010-01-14 00:02:44 +08:00
#define SYMBOL_HASHSIZE 9973
/* A property represent the config options that can be associated
* with a config "symbol".
* Sample:
* config FOO
* default y
* prompt "foo prompt"
* select BAR
* config BAZ
* int "BAZ Value"
* range 1..255
*
* Please, also check zconf.y:print_symbol() when modifying the
* list of property types!
*/
enum prop_type {
P_UNKNOWN,
P_PROMPT, /* prompt "foo prompt" or "BAZ Value" */
P_COMMENT, /* text associated with a comment */
P_MENU, /* prompt associated with a menu or menuconfig symbol */
P_DEFAULT, /* default y */
P_CHOICE, /* choice value */
P_SELECT, /* select BAR */
Kconfig: Introduce the "imply" keyword The "imply" keyword is a weak version of "select" where the target config symbol can still be turned off, avoiding those pitfalls that come with the "select" keyword. This is useful e.g. with multiple drivers that want to indicate their ability to hook into a secondary subsystem while allowing the user to configure that subsystem out without also having to unset these drivers. Currently, the same effect can almost be achieved with: config DRIVER_A tristate config DRIVER_B tristate config DRIVER_C tristate config DRIVER_D tristate [...] config SUBSYSTEM_X tristate default DRIVER_A || DRIVER_B || DRIVER_C || DRIVER_D || [...] This is unwieldy to maintain especially with a large number of drivers. Furthermore, there is no easy way to restrict the choice for SUBSYSTEM_X to y or n, excluding m, when some drivers are built-in. The "select" keyword allows for excluding m, but it excludes n as well. Hence this "imply" keyword. The above becomes: config DRIVER_A tristate imply SUBSYSTEM_X config DRIVER_B tristate imply SUBSYSTEM_X [...] config SUBSYSTEM_X tristate This is much cleaner, and way more flexible than "select". SUBSYSTEM_X can still be configured out, and it can be set as a module when none of the drivers are configured in or all of them are modular. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: linux-kbuild@vger.kernel.org Cc: netdev@vger.kernel.org Cc: Michal Marek <mmarek@suse.com> Cc: Edward Cree <ecree@solarflare.com> Link: http://lkml.kernel.org/r/1478841010-28605-2-git-send-email-nicolas.pitre@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-11 13:10:05 +08:00
P_IMPLY, /* imply BAR */
P_RANGE, /* range 7..100 (for a symbol) */
P_SYMBOL, /* where a symbol is defined */
};
struct property {
struct property *next; /* next property - null if last */
struct symbol *sym; /* the symbol for which the property is associated */
enum prop_type type; /* type of property */
const char *text; /* the prompt value - P_PROMPT, P_MENU, P_COMMENT */
struct expr_value visible;
struct expr *expr; /* the optional conditional part of the property */
struct menu *menu; /* the menu the property are associated with
* valid for: P_SELECT, P_RANGE, P_CHOICE,
* P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
struct file *file; /* what file was this property defined */
int lineno; /* what lineno was this property defined */
};
#define for_all_properties(sym, st, tok) \
for (st = sym->prop; st; st = st->next) \
if (st->type == (tok))
#define for_all_defaults(sym, st) for_all_properties(sym, st, P_DEFAULT)
#define for_all_choices(sym, st) for_all_properties(sym, st, P_CHOICE)
#define for_all_prompts(sym, st) \
for (st = sym->prop; st; st = st->next) \
if (st->text)
/*
* Represents a node in the menu tree, as seen in e.g. menuconfig (though used
* for all front ends). Each symbol, menu, etc. defined in the Kconfig files
* gets a node. A symbol defined in multiple locations gets one node at each
* location.
*/
struct menu {
/* The next menu node at the same level */
struct menu *next;
/* The parent menu node, corresponding to e.g. a menu or choice */
struct menu *parent;
/* The first child menu node, for e.g. menus and choices */
struct menu *list;
/*
* The symbol associated with the menu node. Choices are implemented as
* a special kind of symbol. NULL for menus, comments, and ifs.
*/
struct symbol *sym;
/*
* The prompt associated with the node. This holds the prompt for a
* symbol as well as the text for a menu or comment, along with the
* type (P_PROMPT, P_MENU, etc.)
*/
struct property *prompt;
/*
* 'visible if' dependencies. If more than one is given, they will be
* ANDed together.
*/
struct expr *visibility;
/*
* Ordinary dependencies from e.g. 'depends on' and 'if', ANDed
* together
*/
struct expr *dep;
/* MENU_* flags */
unsigned int flags;
/* Any help text associated with the node */
char *help;
/* The location where the menu node appears in the Kconfig files */
struct file *file;
int lineno;
/* For use by front ends that need to store auxiliary data */
void *data;
};
/*
* Set on a menu node when the corresponding symbol changes state in some way.
* Can be checked by front ends.
*/
#define MENU_CHANGED 0x0001
#define MENU_ROOT 0x0002
struct jump_key {
struct list_head entries;
size_t offset;
struct menu *target;
int index;
};
#define JUMP_NB 9
extern struct file *file_list;
extern struct file *current_file;
struct file *lookup_file(const char *name);
extern struct symbol symbol_yes, symbol_no, symbol_mod;
extern struct symbol *modules_sym;
extern struct symbol *sym_defconfig_list;
extern int cdebug;
struct expr *expr_alloc_symbol(struct symbol *sym);
struct expr *expr_alloc_one(enum expr_type type, struct expr *ce);
struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2);
struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2);
struct expr *expr_alloc_and(struct expr *e1, struct expr *e2);
struct expr *expr_alloc_or(struct expr *e1, struct expr *e2);
struct expr *expr_copy(const struct expr *org);
void expr_free(struct expr *e);
void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
tristate expr_calc_value(struct expr *e);
struct expr *expr_trans_bool(struct expr *e);
struct expr *expr_eliminate_dups(struct expr *e);
struct expr *expr_transform(struct expr *e);
int expr_contains_symbol(struct expr *dep, struct symbol *sym);
bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym);
void expr_fprint(struct expr *e, FILE *out);
struct gstr; /* forward */
void expr_gstr_print(struct expr *e, struct gstr *gs);
kconfig: Print reverse dependencies in groups Surprisingly or not, disabling a CONFIG option (which is assumed to be unneeded) may be not so trivial. Especially it is not trivial, when this CONFIG option is selected by a dozen of other configs. Before the moment commit 1ccb27143360 ("kconfig: make "Selected by:" and "Implied by:" readable") popped up in v4.16-rc1, it was an absolute pain to break down the "Selected by" reverse dependency expression in order to identify all those configs which select (IOW *do not allow disabling*) a certain feature (assumed to be not needed). This patch tries to make one step further by putting at users' fingertips the revdep top level OR sub-expressions grouped/clustered by the tristate value they evaluate to. This should allow the users to directly concentrate on and tackle the _active_ reverse dependencies. To give some numbers and quantify the complexity of certain reverse dependencies, assuming commit 617aebe6a97e ("Merge tag 'usercopy-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux"), ARCH=arm64 and vanilla arm64 defconfig, here is the top 10 CONFIG options with the highest amount of top level "||" sub-expressions/tokens that make up the final "Selected by" reverse dependency expression. | Config | All revdep | Active revdep | |-------------------|------------|---------------| | REGMAP_I2C | 212 | 9 | | CRC32 | 167 | 25 | | FW_LOADER | 128 | 5 | | MFD_CORE | 124 | 9 | | FB_CFB_IMAGEBLIT | 114 | 2 | | FB_CFB_COPYAREA | 111 | 2 | | FB_CFB_FILLRECT | 110 | 2 | | SND_PCM | 103 | 2 | | CRYPTO_HASH | 87 | 19 | | WATCHDOG_CORE | 86 | 6 | The story behind the above is that users need to visually review/evaluate 212 expressions which *potentially* select REGMAP_I2C in order to identify the expressions which *actually* select REGMAP_I2C, for a particular ARCH and for a particular defconfig used. To make this experience smoother, change the way reverse dependencies are displayed to the user from [1] to [2]. [1] Old representation of DMA_ENGINE_RAID: Selected by: - AMCC_PPC440SPE_ADMA [=n] && DMADEVICES [=y] && (440SPe || 440SP) - BCM_SBA_RAID [=m] && DMADEVICES [=y] && (ARM64 [=y] || ... - FSL_RAID [=n] && DMADEVICES [=y] && FSL_SOC && ... - INTEL_IOATDMA [=n] && DMADEVICES [=y] && PCI [=y] && X86_64 - MV_XOR [=n] && DMADEVICES [=y] && (PLAT_ORION || ARCH_MVEBU [=y] ... - MV_XOR_V2 [=y] && DMADEVICES [=y] && ARM64 [=y] - XGENE_DMA [=n] && DMADEVICES [=y] && (ARCH_XGENE [=y] || ... - DMATEST [=n] && DMADEVICES [=y] && DMA_ENGINE [=y] [2] New representation of DMA_ENGINE_RAID: Selected by [y]: - MV_XOR_V2 [=y] && DMADEVICES [=y] && ARM64 [=y] Selected by [m]: - BCM_SBA_RAID [=m] && DMADEVICES [=y] && (ARM64 [=y] || ... Selected by [n]: - AMCC_PPC440SPE_ADMA [=n] && DMADEVICES [=y] && (440SPe || ... - FSL_RAID [=n] && DMADEVICES [=y] && FSL_SOC && ... - INTEL_IOATDMA [=n] && DMADEVICES [=y] && PCI [=y] && X86_64 - MV_XOR [=n] && DMADEVICES [=y] && (PLAT_ORION || ARCH_MVEBU [=y] ... - XGENE_DMA [=n] && DMADEVICES [=y] && (ARCH_XGENE [=y] || ... - DMATEST [=n] && DMADEVICES [=y] && DMA_ENGINE [=y] Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com> Reviewed-by: Petr Vorel <pvorel@suse.cz> Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-02-24 23:24:18 +08:00
void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
tristate pr_type, const char *title);
static inline int expr_is_yes(struct expr *e)
{
return !e || (e->type == E_SYMBOL && e->left.sym == &symbol_yes);
}
static inline int expr_is_no(struct expr *e)
{
return e && (e->type == E_SYMBOL && e->left.sym == &symbol_no);
}
#ifdef __cplusplus
}
#endif
#endif /* EXPR_H */