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Date: Sun, 11 Mar 2018 00:51:59 +0900
From: Masahiro Yamada <yamada.masahiro@...ionext.com>
To: linux-kbuild@...r.kernel.org
Cc: Ulf Magnusson <ulfalizer@...il.com>,
Eugeniu Rosca <erosca@...adit-jv.com>,
Petr Vorel <pvorel@...e.cz>,
Randy Dunlap <rdunlap@...radead.org>,
Sam Ravnborg <sam@...nborg.org>,
Michal Marek <michal.lkml@...kovi.net>,
Masahiro Yamada <yamada.masahiro@...ionext.com>,
linux-kernel@...r.kernel.org
Subject: [PATCH v3] kconfig: make unmet dependency warnings readable
Currently, the unmet dependency warnings end up with endlessly long
expressions, most of which are false positives.
Here is test code to demonstrate how it currently works.
[Test Case]
config DEP1
def_bool y
config DEP2
bool "DEP2"
config A
bool "A"
select E
config B
bool "B"
depends on DEP2
select E
config C
bool "C"
depends on DEP1 && DEP2
select E
config D
def_bool n
select E
config E
bool
depends on DEP1 && DEP2
[Result]
$ make config
scripts/kconfig/conf --oldaskconfig Kconfig
*
* Linux Kernel Configuration
*
DEP2 (DEP2) [N/y/?] (NEW) n
A (A) [N/y/?] (NEW) y
warning: (A && B && D) selects E which has unmet direct
dependencies (DEP1 && DEP2)
Here, I see some points to be improved.
First, '(A || B || D)' would make more sense than '(A && B && D)'.
I am not sure if this is intentional, but expr_simplify_unmet_dep()
turns OR expressions into AND, like follows:
case E_OR:
return expr_alloc_and(
Second, we see false positives. 'A' is a real unmet dependency.
'B' is false positive because 'DEP1' is fixed to 'y', and 'B' depends
on 'DEP2'. 'C' was correctly dropped by expr_simplify_unmet_dep().
'D' is also false positive because it has no chance to be enabled.
Current expr_simplify_unmet_dep() cannot avoid those false positives.
After all, I decided to use the same helpers as used for printing
reverse dependencies in the help.
With this commit, unreadable warnings in the real world:
$ make ARCH=score allyesconfig
scripts/kconfig/conf --allyesconfig Kconfig
warning: (HWSPINLOCK_QCOM && AHCI_MTK && STMMAC_PLATFORM && DWMAC_IPQ806X
&& DWMAC_LPC18XX && DWMAC_OXNAS && DWMAC_ROCKCHIP && DWMAC_SOCFPGA && DWMA
C_STI && TI_CPSW && PINCTRL_GEMINI && PINCTRL_OXNAS && PINCTRL_ROCKCHIP &&
PINCTRL_DOVE && PINCTRL_ARMADA_37XX && PINCTRL_STM32 && S3C2410_WATCHDOG
&& VIDEO_OMAP3 && VIDEO_S5P_FIMC && USB_XHCI_MTK && RTC_DRV_AT91SAM9 && LP
C18XX_DMAMUX && VIDEO_OMAP4 && COMMON_CLK_GEMINI && COMMON_CLK_ASPEED && C
OMMON_CLK_NXP && COMMON_CLK_OXNAS && COMMON_CLK_BOSTON && ATMEL_ST && QCOM
_ADSP_PIL && QCOM_Q6V5_PIL && QCOM_GSBI && ATMEL_EBI && ST_IRQCHIP && RESE
T_IMX7 && PHY_HI6220_USB && PHY_RALINK_USB && PHY_ROCKCHIP_PCIE && PHY_DA8
XX_USB) selects MFD_SYSCON which has unmet direct dependencies (HAS_IOMEM)
warning: (PINCTRL_AT91 && PINCTRL_AT91PIO4 && PINCTRL_OXNAS && PINCTRL_PIS
TACHIO && PINCTRL_PIC32 && PINCTRL_MESON && PINCTRL_NOMADIK && PINCTRL_MTK
&& PINCTRL_MT7622 && GPIO_TB10X) selects OF_GPIO which has unmet direct d
ependencies (GPIOLIB && OF && HAS_IOMEM)
warning: (FAULT_INJECTION_STACKTRACE_FILTER && LATENCYTOP && LOCKDEP) sele
cts FRAME_POINTER which has unmet direct dependencies (DEBUG_KERNEL && (CR
IS || M68K || FRV || UML || SUPERH || BLACKFIN || MN10300 || METAG) || ARC
H_WANT_FRAME_POINTERS)
will be turned into:
$ make ARCH=score allyesconfig
scripts/kconfig/conf --allyesconfig Kconfig
WARNING: unmet direct dependencies detected for MFD_SYSCON
Depends on:
HAS_IOMEM [=n]
Selected by [y]:
- PINCTRL_STM32 [=y] && PINCTRL [=y] && (ARCH_STM32 || COMPILE_TEST [=y])
&& OF [=y]
- RTC_DRV_AT91SAM9 [=y] && RTC_CLASS [=y] && (ARCH_AT91 || COMPILE_TEST
[=y])
- ATMEL_ST [=y] && GENERIC_CLOCKEVENTS [=y]
- RESET_IMX7 [=y] && RESET_CONTROLLER [=y]
- PHY_HI6220_USB [=y] && (ARCH_HISI && ARM64 || COMPILE_TEST [=y])
- PHY_RALINK_USB [=y] && (RALINK || COMPILE_TEST [=y])
- PHY_ROCKCHIP_PCIE [=y] && (ARCH_ROCKCHIP && OF [=y] || COMPILE_TEST
[=y])
WARNING: unmet direct dependencies detected for OF_GPIO
Depends on:
GPIOLIB [=y] && OF [=y] && HAS_IOMEM [=n]
Selected by [y]:
- PINCTRL_MTK [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST
[=y]) && OF [=y]
- PINCTRL_MT7622 [=y] && PINCTRL [=y] && (ARCH_MEDIATEK || COMPILE_TEST
[=y]) && OF [=y] && (ARM64 || COMPILE_TEST [=y])
WARNING: unmet direct dependencies detected for FRAME_POINTER
Depends on:
DEBUG_KERNEL [=y] && (CRIS || M68K || FRV || UML || SUPERH || BLACKFIN
|| MN10300 || METAG) || ARCH_WANT_FRAME_POINTERS [=n]
Selected by [y]:
- LATENCYTOP [=y] && DEBUG_KERNEL [=y] && STACKTRACE_SUPPORT [=y] &&
PROC_FS [=y] && !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND &&
!ARC && !X86
Signed-off-by: Masahiro Yamada <yamada.masahiro@...ionext.com>
Reviewed-by: Petr Vorel <petr.vorel@...il.com>
---
Changes in v3:
- Remove unused expr_get_leftmost_symbol()
- Move error message to the same line as 'WARNING'
- update test case
Changes in v2:
- update test case
scripts/kconfig/expr.c | 42 ------------------------------------------
scripts/kconfig/expr.h | 1 -
scripts/kconfig/symbol.c | 34 ++++++++++++++++++++++------------
3 files changed, 22 insertions(+), 55 deletions(-)
diff --git a/scripts/kconfig/expr.c b/scripts/kconfig/expr.c
index 49376e1..e1a39e9 100644
--- a/scripts/kconfig/expr.c
+++ b/scripts/kconfig/expr.c
@@ -1137,48 +1137,6 @@ static int expr_compare_type(enum expr_type t1, enum expr_type t2)
return 0;
}
-static inline struct expr *
-expr_get_leftmost_symbol(const struct expr *e)
-{
-
- if (e == NULL)
- return NULL;
-
- while (e->type != E_SYMBOL)
- e = e->left.expr;
-
- return expr_copy(e);
-}
-
-/*
- * Given expression `e1' and `e2', returns the leaf of the longest
- * sub-expression of `e1' not containing 'e2.
- */
-struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2)
-{
- struct expr *ret;
-
- switch (e1->type) {
- case E_OR:
- return expr_alloc_and(
- expr_simplify_unmet_dep(e1->left.expr, e2),
- expr_simplify_unmet_dep(e1->right.expr, e2));
- case E_AND: {
- struct expr *e;
- e = expr_alloc_and(expr_copy(e1), expr_copy(e2));
- e = expr_eliminate_dups(e);
- ret = (!expr_eq(e, e1)) ? e1 : NULL;
- expr_free(e);
- break;
- }
- default:
- ret = e1;
- break;
- }
-
- return expr_get_leftmost_symbol(ret);
-}
-
void expr_print(struct expr *e,
void (*fn)(void *, struct symbol *, const char *),
void *data, int prevtoken)
diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 8dbf2a4..94a383b 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -305,7 +305,6 @@ 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);
-struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2);
void expr_fprint(struct expr *e, FILE *out);
struct gstr; /* forward */
diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
index 0f7eba7..8b13c16 100644
--- a/scripts/kconfig/symbol.c
+++ b/scripts/kconfig/symbol.c
@@ -333,6 +333,26 @@ static struct symbol *sym_calc_choice(struct symbol *sym)
return def_sym;
}
+static void sym_warn_unmet_dependency(struct symbol *sym)
+{
+ struct gstr gs = str_new();
+
+ str_printf(&gs,
+ "\nWARNING: unmet direct dependencies detected for %s\n"
+ " Depends on:\n"
+ " ",
+ sym->name);
+ expr_gstr_print(sym->dir_dep.expr, &gs);
+ str_printf(&gs, "\n");
+
+ expr_gstr_print_revdep(sym->rev_dep.expr, &gs, yes,
+ " Selected by [y]:\n");
+ expr_gstr_print_revdep(sym->rev_dep.expr, &gs, mod,
+ " Selected by [m]:\n");
+
+ fputs(str_get(&gs), stderr);
+}
+
void sym_calc_value(struct symbol *sym)
{
struct symbol_value newval, oldval;
@@ -414,18 +434,8 @@ void sym_calc_value(struct symbol *sym)
}
}
calc_newval:
- if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
- struct expr *e;
- e = expr_simplify_unmet_dep(sym->rev_dep.expr,
- sym->dir_dep.expr);
- fprintf(stderr, "warning: (");
- expr_fprint(e, stderr);
- fprintf(stderr, ") selects %s which has unmet direct dependencies (",
- sym->name);
- expr_fprint(sym->dir_dep.expr, stderr);
- fprintf(stderr, ")\n");
- expr_free(e);
- }
+ if (sym->dir_dep.tri == no && sym->rev_dep.tri != no)
+ sym_warn_unmet_dependency(sym);
newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
}
if (newval.tri == mod &&
--
2.7.4
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