From d9119b5925a03b9a3191fa3e93b4091651d8ad25 Mon Sep 17 00:00:00 2001 From: Eugeniu Rosca Date: Sat, 24 Feb 2018 16:24:18 +0100 Subject: [PATCH] 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 Signed-off-by: Eugeniu Rosca Reviewed-by: Petr Vorel Reviewed-by: Ulf Magnusson Signed-off-by: Masahiro Yamada --- scripts/kconfig/expr.c | 18 ++++++++++++------ scripts/kconfig/expr.h | 3 ++- scripts/kconfig/menu.c | 12 ++++++------ 3 files changed, 20 insertions(+), 13 deletions(-) diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c index cd3a8f501f38..49376e12fa30 100644 --- a/scripts/kconfig/expr.c +++ b/scripts/kconfig/expr.c @@ -1323,19 +1323,25 @@ void expr_gstr_print(struct expr *e, struct gstr *gs) */ static void expr_print_revdep(struct expr *e, void (*fn)(void *, struct symbol *, const char *), - void *data) + void *data, tristate pr_type, const char **title) { if (e->type == E_OR) { - expr_print_revdep(e->left.expr, fn, data); - expr_print_revdep(e->right.expr, fn, data); - } else { + expr_print_revdep(e->left.expr, fn, data, pr_type, title); + expr_print_revdep(e->right.expr, fn, data, pr_type, title); + } else if (expr_calc_value(e) == pr_type) { + if (*title) { + fn(data, NULL, *title); + *title = NULL; + } + fn(data, NULL, " - "); expr_print(e, fn, data, E_NONE); fn(data, NULL, "\n"); } } -void expr_gstr_print_revdep(struct expr *e, struct gstr *gs) +void expr_gstr_print_revdep(struct expr *e, struct gstr *gs, + tristate pr_type, const char *title) { - expr_print_revdep(e, expr_print_gstr_helper, gs); + expr_print_revdep(e, expr_print_gstr_helper, gs, pr_type, &title); } diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h index c16e82e302a2..8dbf2a4cdae1 100644 --- a/scripts/kconfig/expr.h +++ b/scripts/kconfig/expr.h @@ -310,7 +310,8 @@ struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2); void expr_fprint(struct expr *e, FILE *out); struct gstr; /* forward */ void expr_gstr_print(struct expr *e, struct gstr *gs); -void expr_gstr_print_revdep(struct expr *e, struct gstr *gs); +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) { diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c index 02f46813e732..5c5c1374b151 100644 --- a/scripts/kconfig/menu.c +++ b/scripts/kconfig/menu.c @@ -828,16 +828,16 @@ static void get_symbol_str(struct gstr *r, struct symbol *sym, get_symbol_props_str(r, sym, P_SELECT, _(" Selects: ")); if (sym->rev_dep.expr) { - str_append(r, _(" Selected by: ")); - str_append(r, "\n"); - expr_gstr_print_revdep(sym->rev_dep.expr, r); + expr_gstr_print_revdep(sym->rev_dep.expr, r, yes, " Selected by [y]:\n"); + expr_gstr_print_revdep(sym->rev_dep.expr, r, mod, " Selected by [m]:\n"); + expr_gstr_print_revdep(sym->rev_dep.expr, r, no, " Selected by [n]:\n"); } get_symbol_props_str(r, sym, P_IMPLY, _(" Implies: ")); if (sym->implied.expr) { - str_append(r, _(" Implied by: ")); - str_append(r, "\n"); - expr_gstr_print_revdep(sym->implied.expr, r); + expr_gstr_print_revdep(sym->implied.expr, r, yes, " Implied by [y]:\n"); + expr_gstr_print_revdep(sym->implied.expr, r, mod, " Implied by [m]:\n"); + expr_gstr_print_revdep(sym->implied.expr, r, no, " Implied by [n]:\n"); } str_append(r, "\n\n");