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bh=QjDfRB3lIvJuY5J+9JPtXMit1q+Foy4/MtvzENxo+Qg=; b=nChNo2shdCs3FQxZqv9s6Rgoa0rxoIiyasXNmG/fz9X7FHeG8lxb/OJarcBuNavgIA y91UXhPdLuPwpZQvDOteO//s3g3t2Bls85xY2wSbAFTzKOduX9S6sA9X4ZYZz9OO4aA8 qi1nvZumMgJOc6mXpB8Wp6DO/OwY4Yp8zE2+kC/vNpagOukGoxvC6Nt3X0ofakFtpnFQ xqzAP3guj+Q7o/VVNl1z0JIRPGk9JRG3Ta8a4tBT1zrl9uUMjOX35pAS/oi/Qku8Z/bg kl1eyTZaRki4tHJ2/kF6rvwotNUoE0ScecYc5YvnnTyS+LJiml1QD6N1QnBc/toceWsT hN3w== X-Gm-Message-State: AMCzsaVXUnGQfl3aPOYQMiYTsrymLnabCMQ9JQHOycSFvLHOS/PRzjLW 4JyWp4zuBbDvIgTRxQo8fko9NA== X-Google-Smtp-Source: ABhQp+QV9b9+yGSTHreK6Ug3aFPtLQfx7M39VPTvPrr1eVawfXQYo60V2aBjMLhtfrH8pbwddB1PwQ== X-Received: by 10.107.143.200 with SMTP id r191mr20590652iod.172.1510002226169; Mon, 06 Nov 2017 13:03:46 -0800 (PST) Received: from nebulus.mtv.corp.google.com ([100.98.120.17]) by smtp.gmail.com with ESMTPSA id y41sm4841945ita.22.2017.11.06.13.03.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 06 Nov 2017 13:03:45 -0800 (PST) From: Mark Salyzyn To: linux-kernel@vger.kernel.org Subject: [PATCH v5 10/12] arm64: vdso: replace gettimeofday.S with global vgettimeofday.C Date: Mon, 6 Nov 2017 13:03:24 -0800 Message-Id: <20171106210341.95256-1-salyzyn@android.com> X-Mailer: git-send-email 2.15.0.403.gc27cc4dac6-goog X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20171106_130407_708318_CF05FB70 X-CRM114-Status: GOOD ( 22.56 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Kate Stewart , Laura Abbott , Kees Cook , Ard Biesheuvel , Catalin Marinas , Kevin Brodsky , Will Deacon , Russell King , Andy Lutomirski , Greg Kroah-Hartman , Philippe Ombredanne , James Morse , Andrew Pinski , Dmitry Safonov , Andy Gross , John Stultz , Thomas Gleixner , Mark Salyzyn , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Take an effort from the previous 9 patches to recode the arm64 vdso code from assembler to C previously submitted by Andrew Pinski , rework it for use in both arm and arm64, overlapping any optimizations for each architecture. But instead of landing it in arm64, land the result into lib/vdso and unify both implementations to simplify future maintenance. apinski@cavium.com makes the following claims in the original patch: This allows the compiler to optimize the divide by 1000 and remove the other divides. On ThunderX, gettimeofday improves by 32%. On ThunderX 2, gettimeofday improves by 18%. Note I noticed a bug in the old (arm64) implementation of __kernel_clock_getres; it was checking only the lower 32bits of the pointer; this would work for most cases but could fail in a few. (asm fix supplied by Will Deacon for stable) Signed-off-by: Mark Salyzyn Cc: James Morse Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Andy Lutomirski Cc: Dmitry Safonov Cc: John Stultz Cc: Mark Rutland Cc: Laura Abbott Cc: Kees Cook Cc: Ard Biesheuvel Cc: Andy Gross Cc: Kevin Brodsky Cc: Andrew Pinski Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org v2: - turned off profiling, restored quiet_cmd_vdsoas. v3: - move arch/arm/vdso/vgettimeofday.c to lib/vdso/vgettimeofday.c. - adjust vgettimeofday.c to be a better global candidate, switch to using ARCH_PROVIDES_TIMER and __arch_counter_get() as more generic. v4: - simplify arch_vdso_read_counter, use read_sysreg. - Use GENMASK_ULL macro for ARCH_CLOCK_FIXED_MASK. - update commit message. - add vdso_wtm_clock_nsec_t, vdso_xtime_clock_sec_t and vdso_raw_time_nsec_t. v5: - comment about asm/processor.h and asm/sysreg.h regarding why they have been added in compiler.h for porting clarity. - add linux/hrtimer.h to compiler.h and comment for porting clarity. - strip out excess unused definitions in asm-offsets.c. - fix clang build errors --- arch/arm64/include/asm/vdso_datapage.h | 23 ++- arch/arm64/kernel/asm-offsets.c | 34 ---- arch/arm64/kernel/vdso.c | 2 +- arch/arm64/kernel/vdso/Makefile | 29 ++- arch/arm64/kernel/vdso/compiler.h | 69 +++++++ arch/arm64/kernel/vdso/datapage.h | 59 ++++++ arch/arm64/kernel/vdso/gettimeofday.S | 328 --------------------------------- arch/arm64/kernel/vdso/vgettimeofday.c | 3 + 8 files changed, 175 insertions(+), 372 deletions(-) create mode 100644 arch/arm64/kernel/vdso/compiler.h create mode 100644 arch/arm64/kernel/vdso/datapage.h delete mode 100644 arch/arm64/kernel/vdso/gettimeofday.S create mode 100644 arch/arm64/kernel/vdso/vgettimeofday.c diff --git a/arch/arm64/include/asm/vdso_datapage.h b/arch/arm64/include/asm/vdso_datapage.h index 2b9a63771eda..95f4a7abab80 100644 --- a/arch/arm64/include/asm/vdso_datapage.h +++ b/arch/arm64/include/asm/vdso_datapage.h @@ -20,16 +20,31 @@ #ifndef __ASSEMBLY__ +#ifndef _VDSO_WTM_CLOCK_SEC_T +#define _VDSO_WTM_CLOCK_SEC_T +typedef __u64 vdso_wtm_clock_nsec_t; +#endif + +#ifndef _VDSO_XTIME_CLOCK_SEC_T +#define _VDSO_XTIME_CLOCK_SEC_T +typedef __u64 vdso_xtime_clock_sec_t; +#endif + +#ifndef _VDSO_RAW_TIME_SEC_T +#define _VDSO_RAW_TIME_SEC_T +typedef __u64 vdso_raw_time_sec_t; +#endif + struct vdso_data { __u64 cs_cycle_last; /* Timebase at clocksource init */ - __u64 raw_time_sec; /* Raw time */ + vdso_raw_time_sec_t raw_time_sec; /* Raw time */ __u64 raw_time_nsec; - __u64 xtime_clock_sec; /* Kernel time */ - __u64 xtime_clock_nsec; + vdso_xtime_clock_sec_t xtime_clock_sec; /* Kernel time */ + __u64 xtime_clock_snsec; __u64 xtime_coarse_sec; /* Coarse time */ __u64 xtime_coarse_nsec; __u64 wtm_clock_sec; /* Wall to monotonic time */ - __u64 wtm_clock_nsec; + vdso_wtm_clock_nsec_t wtm_clock_nsec; __u32 tb_seq_count; /* Timebase sequence counter */ /* cs_* members must be adjacent and in this order (ldp accesses) */ __u32 cs_mono_mult; /* NTP-adjusted clocksource multiplier */ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index 71bf088f1e4b..c5d0e2a6db49 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -91,40 +91,6 @@ int main(void) DEFINE(DMA_TO_DEVICE, DMA_TO_DEVICE); DEFINE(DMA_FROM_DEVICE, DMA_FROM_DEVICE); BLANK(); - DEFINE(CLOCK_REALTIME, CLOCK_REALTIME); - DEFINE(CLOCK_MONOTONIC, CLOCK_MONOTONIC); - DEFINE(CLOCK_MONOTONIC_RAW, CLOCK_MONOTONIC_RAW); - DEFINE(CLOCK_REALTIME_RES, MONOTONIC_RES_NSEC); - DEFINE(CLOCK_REALTIME_COARSE, CLOCK_REALTIME_COARSE); - DEFINE(CLOCK_MONOTONIC_COARSE,CLOCK_MONOTONIC_COARSE); - DEFINE(CLOCK_COARSE_RES, LOW_RES_NSEC); - DEFINE(NSEC_PER_SEC, NSEC_PER_SEC); - BLANK(); - DEFINE(VDSO_CS_CYCLE_LAST, offsetof(struct vdso_data, cs_cycle_last)); - DEFINE(VDSO_RAW_TIME_SEC, offsetof(struct vdso_data, raw_time_sec)); - DEFINE(VDSO_RAW_TIME_NSEC, offsetof(struct vdso_data, raw_time_nsec)); - DEFINE(VDSO_XTIME_CLK_SEC, offsetof(struct vdso_data, xtime_clock_sec)); - DEFINE(VDSO_XTIME_CLK_NSEC, offsetof(struct vdso_data, xtime_clock_nsec)); - DEFINE(VDSO_XTIME_CRS_SEC, offsetof(struct vdso_data, xtime_coarse_sec)); - DEFINE(VDSO_XTIME_CRS_NSEC, offsetof(struct vdso_data, xtime_coarse_nsec)); - DEFINE(VDSO_WTM_CLK_SEC, offsetof(struct vdso_data, wtm_clock_sec)); - DEFINE(VDSO_WTM_CLK_NSEC, offsetof(struct vdso_data, wtm_clock_nsec)); - DEFINE(VDSO_TB_SEQ_COUNT, offsetof(struct vdso_data, tb_seq_count)); - DEFINE(VDSO_CS_MONO_MULT, offsetof(struct vdso_data, cs_mono_mult)); - DEFINE(VDSO_CS_RAW_MULT, offsetof(struct vdso_data, cs_raw_mult)); - DEFINE(VDSO_CS_SHIFT, offsetof(struct vdso_data, cs_shift)); - DEFINE(VDSO_TZ_MINWEST, offsetof(struct vdso_data, tz_minuteswest)); - DEFINE(VDSO_TZ_DSTTIME, offsetof(struct vdso_data, tz_dsttime)); - DEFINE(VDSO_USE_SYSCALL, offsetof(struct vdso_data, use_syscall)); - BLANK(); - DEFINE(TVAL_TV_SEC, offsetof(struct timeval, tv_sec)); - DEFINE(TVAL_TV_USEC, offsetof(struct timeval, tv_usec)); - DEFINE(TSPEC_TV_SEC, offsetof(struct timespec, tv_sec)); - DEFINE(TSPEC_TV_NSEC, offsetof(struct timespec, tv_nsec)); - BLANK(); - DEFINE(TZ_MINWEST, offsetof(struct timezone, tz_minuteswest)); - DEFINE(TZ_DSTTIME, offsetof(struct timezone, tz_dsttime)); - BLANK(); DEFINE(CPU_BOOT_STACK, offsetof(struct secondary_data, stack)); DEFINE(CPU_BOOT_TASK, offsetof(struct secondary_data, task)); BLANK(); diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 2d419006ad43..59f150c25889 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -238,7 +238,7 @@ void update_vsyscall(struct timekeeper *tk) vdso_data->raw_time_sec = tk->raw_sec; vdso_data->raw_time_nsec = tk->tkr_raw.xtime_nsec; vdso_data->xtime_clock_sec = tk->xtime_sec; - vdso_data->xtime_clock_nsec = tk->tkr_mono.xtime_nsec; + vdso_data->xtime_clock_snsec = tk->tkr_mono.xtime_nsec; vdso_data->cs_mono_mult = tk->tkr_mono.mult; vdso_data->cs_raw_mult = tk->tkr_raw.mult; /* tkr_mono.shift == tkr_raw.shift */ diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile index b215c712d897..21cad81a4f40 100644 --- a/arch/arm64/kernel/vdso/Makefile +++ b/arch/arm64/kernel/vdso/Makefile @@ -6,18 +6,32 @@ # Heavily based on the vDSO Makefiles for other archs. # -obj-vdso := gettimeofday.o note.o sigreturn.o +obj-vdso-s := note.o sigreturn.o +obj-vdso-c := vgettimeofday.o # Build rules -targets := $(obj-vdso) vdso.so vdso.so.dbg -obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) +targets := $(obj-vdso-s) $(obj-vdso-c) vdso.so vdso.so.dbg +obj-vdso-s := $(addprefix $(obj)/, $(obj-vdso-s)) +obj-vdso-c := $(addprefix $(obj)/, $(obj-vdso-c)) +obj-vdso := $(obj-vdso-c) $(obj-vdso-s) -ccflags-y := -shared -fno-common -fno-builtin +ccflags-y := -shared -fno-common -fno-builtin -fno-stack-protector +ccflags-y += -DDISABLE_BRANCH_PROFILING ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 \ $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) +# Force -O2 to avoid libgcc dependencies +CFLAGS_REMOVE_vgettimeofday.o = -pg -Os +CFLAGS_vgettimeofday.o = -O2 -fPIC +ifneq ($(cc-name),clang) +CFLAGS_vgettimeofday.o += -mcmodel=tiny +endif + # Disable gcov profiling for VDSO code GCOV_PROFILE := n +KASAN_SANITIZE := n +UBSAN_SANITIZE := n +KCOV_INSTRUMENT := n # Workaround for bare-metal (ELF) toolchains that neglect to pass -shared # down to collect2, resulting in silent corruption of the vDSO image. @@ -50,12 +64,17 @@ include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE $(call if_changed,vdsosym) # Assembly rules for the .S files -$(obj-vdso): %.o: %.S FORCE +$(obj-vdso-s): %.o: %.S FORCE $(call if_changed_dep,vdsoas) +$(obj-vdso-c): %.o: %.c FORCE + $(call if_changed_dep,vdsocc) + # Actual build commands quiet_cmd_vdsold = VDSOL $@ cmd_vdsold = $(CC) $(c_flags) -Wl,-n -Wl,-T $^ -o $@ +quiet_cmd_vdsocc = VDSOC $@ + cmd_vdsocc = ${CC} $(c_flags) -c -o $@ $< quiet_cmd_vdsoas = VDSOA $@ cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $< diff --git a/arch/arm64/kernel/vdso/compiler.h b/arch/arm64/kernel/vdso/compiler.h new file mode 100644 index 000000000000..921a7191b497 --- /dev/null +++ b/arch/arm64/kernel/vdso/compiler.h @@ -0,0 +1,69 @@ +/* + * Userspace implementations of fallback calls + * + * Copyright (C) 2017 Cavium, Inc. + * Copyright (C) 2012 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + * + * Author: Will Deacon + * Rewriten into C by: Andrew Pinski + */ + +#ifndef __VDSO_COMPILER_H +#define __VDSO_COMPILER_H + +#include /* for cpu_relax() */ +#include /* for read_sysreg() */ +#include +#include +#include /* for LOW_RES_NSEC and MONOTONIC_RES_NSEC */ + +#ifdef CONFIG_ARM_ARCH_TIMER +#define ARCH_PROVIDES_TIMER +#endif + +#define DEFINE_FALLBACK(name, type_arg1, name_arg1, type_arg2, name_arg2) \ +static notrace long name##_fallback(type_arg1 _##name_arg1, \ + type_arg2 _##name_arg2) \ +{ \ + register type_arg1 name_arg1 asm("x0") = _##name_arg1; \ + register type_arg2 name_arg2 asm("x1") = _##name_arg2; \ + register long ret asm ("x0"); \ + register long nr asm("x8") = __NR_##name; \ + \ + asm volatile( \ + " svc #0\n" \ + : "=r" (ret) \ + : "r" (name_arg1), "r" (name_arg2), "r" (nr) \ + : "memory"); \ + \ + return ret; \ +} + +/* + * AArch64 implementation of arch_counter_get_cntvct() suitable for vdso + */ +static __always_inline notrace u64 arch_vdso_read_counter(void) +{ + /* Read the virtual counter. */ + isb(); + return read_sysreg(cntvct_el0); +} + +/* Rename exported vdso functions */ +#define __vdso_clock_gettime __kernel_clock_gettime +#define __vdso_gettimeofday __kernel_gettimeofday +#define __vdso_clock_getres __kernel_clock_getres + +#endif /* __VDSO_COMPILER_H */ diff --git a/arch/arm64/kernel/vdso/datapage.h b/arch/arm64/kernel/vdso/datapage.h new file mode 100644 index 000000000000..be86a6074cf8 --- /dev/null +++ b/arch/arm64/kernel/vdso/datapage.h @@ -0,0 +1,59 @@ +/* + * Userspace implementations of __get_datapage + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#ifndef __VDSO_DATAPAGE_H +#define __VDSO_DATAPAGE_H + +#include +#include +#include + +/* + * We use the hidden visibility to prevent the compiler from generating a GOT + * relocation. Not only is going through a GOT useless (the entry couldn't and + * mustn't be overridden by another library), it does not even work: the linker + * cannot generate an absolute address to the data page. + * + * With the hidden visibility, the compiler simply generates a PC-relative + * relocation (R_ARM_REL32), and this is what we need. + */ +extern const struct vdso_data _vdso_data __attribute__((visibility("hidden"))); + +static inline const struct vdso_data *__get_datapage(void) +{ + const struct vdso_data *ret; + /* + * This simply puts &_vdso_data into ret. The reason why we don't use + * `ret = &_vdso_data` is that the compiler tends to optimise this in a + * very suboptimal way: instead of keeping &_vdso_data in a register, + * it goes through a relocation almost every time _vdso_data must be + * accessed (even in subfunctions). This is both time and space + * consuming: each relocation uses a word in the code section, and it + * has to be loaded at runtime. + * + * This trick hides the assignment from the compiler. Since it cannot + * track where the pointer comes from, it will only use one relocation + * where __get_datapage() is called, and then keep the result in a + * register. + */ + asm("" : "=r"(ret) : "0"(&_vdso_data)); + return ret; +} + +/* We can only guarantee 56 bits of precision. */ +#define ARCH_CLOCK_FIXED_MASK GENMASK_ULL(55, 0) + +#endif /* __VDSO_DATAPAGE_H */ diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S deleted file mode 100644 index 76320e920965..000000000000 --- a/arch/arm64/kernel/vdso/gettimeofday.S +++ /dev/null @@ -1,328 +0,0 @@ -/* - * Userspace implementations of gettimeofday() and friends. - * - * Copyright (C) 2012 ARM Limited - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see . - * - * Author: Will Deacon - */ - -#include -#include -#include - -#define NSEC_PER_SEC_LO16 0xca00 -#define NSEC_PER_SEC_HI16 0x3b9a - -vdso_data .req x6 -seqcnt .req w7 -w_tmp .req w8 -x_tmp .req x8 - -/* - * Conventions for macro arguments: - * - An argument is write-only if its name starts with "res". - * - All other arguments are read-only, unless otherwise specified. - */ - - .macro seqcnt_acquire -9999: ldr seqcnt, [vdso_data, #VDSO_TB_SEQ_COUNT] - tbnz seqcnt, #0, 9999b - dmb ishld - .endm - - .macro seqcnt_check fail - dmb ishld - ldr w_tmp, [vdso_data, #VDSO_TB_SEQ_COUNT] - cmp w_tmp, seqcnt - b.ne \fail - .endm - - .macro syscall_check fail - ldr w_tmp, [vdso_data, #VDSO_USE_SYSCALL] - cbnz w_tmp, \fail - .endm - - .macro get_nsec_per_sec res - mov \res, #NSEC_PER_SEC_LO16 - movk \res, #NSEC_PER_SEC_HI16, lsl #16 - .endm - - /* - * Returns the clock delta, in nanoseconds left-shifted by the clock - * shift. - */ - .macro get_clock_shifted_nsec res, cycle_last, mult - /* Read the virtual counter. */ - isb - mrs x_tmp, cntvct_el0 - /* Calculate cycle delta and convert to ns. */ - sub \res, x_tmp, \cycle_last - /* We can only guarantee 56 bits of precision. */ - movn x_tmp, #0xff00, lsl #48 - and \res, x_tmp, \res - mul \res, \res, \mult - .endm - - /* - * Returns in res_{sec,nsec} the REALTIME timespec, based on the - * "wall time" (xtime) and the clock_mono delta. - */ - .macro get_ts_realtime res_sec, res_nsec, \ - clock_nsec, xtime_sec, xtime_nsec, nsec_to_sec - add \res_nsec, \clock_nsec, \xtime_nsec - udiv x_tmp, \res_nsec, \nsec_to_sec - add \res_sec, \xtime_sec, x_tmp - msub \res_nsec, x_tmp, \nsec_to_sec, \res_nsec - .endm - - /* - * Returns in res_{sec,nsec} the timespec based on the clock_raw delta, - * used for CLOCK_MONOTONIC_RAW. - */ - .macro get_ts_clock_raw res_sec, res_nsec, clock_nsec, nsec_to_sec - udiv \res_sec, \clock_nsec, \nsec_to_sec - msub \res_nsec, \res_sec, \nsec_to_sec, \clock_nsec - .endm - - /* sec and nsec are modified in place. */ - .macro add_ts sec, nsec, ts_sec, ts_nsec, nsec_to_sec - /* Add timespec. */ - add \sec, \sec, \ts_sec - add \nsec, \nsec, \ts_nsec - - /* Normalise the new timespec. */ - cmp \nsec, \nsec_to_sec - b.lt 9999f - sub \nsec, \nsec, \nsec_to_sec - add \sec, \sec, #1 -9999: - cmp \nsec, #0 - b.ge 9998f - add \nsec, \nsec, \nsec_to_sec - sub \sec, \sec, #1 -9998: - .endm - - .macro clock_gettime_return, shift=0 - .if \shift == 1 - lsr x11, x11, x12 - .endif - stp x10, x11, [x1, #TSPEC_TV_SEC] - mov x0, xzr - ret - .endm - - .macro jump_slot jumptable, index, label - .if (. - \jumptable) != 4 * (\index) - .error "Jump slot index mismatch" - .endif - b \label - .endm - - .text - -/* int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz); */ -ENTRY(__kernel_gettimeofday) - .cfi_startproc - adr vdso_data, _vdso_data - /* If tv is NULL, skip to the timezone code. */ - cbz x0, 2f - - /* Compute the time of day. */ -1: seqcnt_acquire - syscall_check fail=4f - ldr x10, [vdso_data, #VDSO_CS_CYCLE_LAST] - /* w11 = cs_mono_mult, w12 = cs_shift */ - ldp w11, w12, [vdso_data, #VDSO_CS_MONO_MULT] - ldp x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC] - seqcnt_check fail=1b - - get_nsec_per_sec res=x9 - lsl x9, x9, x12 - - get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 - get_ts_realtime res_sec=x10, res_nsec=x11, \ - clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9 - - /* Convert ns to us. */ - mov x13, #1000 - lsl x13, x13, x12 - udiv x11, x11, x13 - stp x10, x11, [x0, #TVAL_TV_SEC] -2: - /* If tz is NULL, return 0. */ - cbz x1, 3f - ldp w4, w5, [vdso_data, #VDSO_TZ_MINWEST] - stp w4, w5, [x1, #TZ_MINWEST] -3: - mov x0, xzr - ret -4: - /* Syscall fallback. */ - mov x8, #__NR_gettimeofday - svc #0 - ret - .cfi_endproc -ENDPROC(__kernel_gettimeofday) - -#define JUMPSLOT_MAX CLOCK_MONOTONIC_COARSE - -/* int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp); */ -ENTRY(__kernel_clock_gettime) - .cfi_startproc - cmp w0, #JUMPSLOT_MAX - b.hi syscall - adr vdso_data, _vdso_data - adr x_tmp, jumptable - add x_tmp, x_tmp, w0, uxtw #2 - br x_tmp - - ALIGN -jumptable: - jump_slot jumptable, CLOCK_REALTIME, realtime - jump_slot jumptable, CLOCK_MONOTONIC, monotonic - b syscall - b syscall - jump_slot jumptable, CLOCK_MONOTONIC_RAW, monotonic_raw - jump_slot jumptable, CLOCK_REALTIME_COARSE, realtime_coarse - jump_slot jumptable, CLOCK_MONOTONIC_COARSE, monotonic_coarse - - .if (. - jumptable) != 4 * (JUMPSLOT_MAX + 1) - .error "Wrong jumptable size" - .endif - - ALIGN -realtime: - seqcnt_acquire - syscall_check fail=syscall - ldr x10, [vdso_data, #VDSO_CS_CYCLE_LAST] - /* w11 = cs_mono_mult, w12 = cs_shift */ - ldp w11, w12, [vdso_data, #VDSO_CS_MONO_MULT] - ldp x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC] - seqcnt_check fail=realtime - - /* All computations are done with left-shifted nsecs. */ - get_nsec_per_sec res=x9 - lsl x9, x9, x12 - - get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 - get_ts_realtime res_sec=x10, res_nsec=x11, \ - clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9 - clock_gettime_return, shift=1 - - ALIGN -monotonic: - seqcnt_acquire - syscall_check fail=syscall - ldr x10, [vdso_data, #VDSO_CS_CYCLE_LAST] - /* w11 = cs_mono_mult, w12 = cs_shift */ - ldp w11, w12, [vdso_data, #VDSO_CS_MONO_MULT] - ldp x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC] - ldp x3, x4, [vdso_data, #VDSO_WTM_CLK_SEC] - seqcnt_check fail=monotonic - - /* All computations are done with left-shifted nsecs. */ - lsl x4, x4, x12 - get_nsec_per_sec res=x9 - lsl x9, x9, x12 - - get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 - get_ts_realtime res_sec=x10, res_nsec=x11, \ - clock_nsec=x15, xtime_sec=x13, xtime_nsec=x14, nsec_to_sec=x9 - - add_ts sec=x10, nsec=x11, ts_sec=x3, ts_nsec=x4, nsec_to_sec=x9 - clock_gettime_return, shift=1 - - ALIGN -monotonic_raw: - seqcnt_acquire - syscall_check fail=syscall - ldr x10, [vdso_data, #VDSO_CS_CYCLE_LAST] - /* w11 = cs_raw_mult, w12 = cs_shift */ - ldp w12, w11, [vdso_data, #VDSO_CS_SHIFT] - ldp x13, x14, [vdso_data, #VDSO_RAW_TIME_SEC] - seqcnt_check fail=monotonic_raw - - /* All computations are done with left-shifted nsecs. */ - get_nsec_per_sec res=x9 - lsl x9, x9, x12 - - get_clock_shifted_nsec res=x15, cycle_last=x10, mult=x11 - get_ts_clock_raw res_sec=x10, res_nsec=x11, \ - clock_nsec=x15, nsec_to_sec=x9 - - add_ts sec=x10, nsec=x11, ts_sec=x13, ts_nsec=x14, nsec_to_sec=x9 - clock_gettime_return, shift=1 - - ALIGN -realtime_coarse: - seqcnt_acquire - ldp x10, x11, [vdso_data, #VDSO_XTIME_CRS_SEC] - seqcnt_check fail=realtime_coarse - clock_gettime_return - - ALIGN -monotonic_coarse: - seqcnt_acquire - ldp x10, x11, [vdso_data, #VDSO_XTIME_CRS_SEC] - ldp x13, x14, [vdso_data, #VDSO_WTM_CLK_SEC] - seqcnt_check fail=monotonic_coarse - - /* Computations are done in (non-shifted) nsecs. */ - get_nsec_per_sec res=x9 - add_ts sec=x10, nsec=x11, ts_sec=x13, ts_nsec=x14, nsec_to_sec=x9 - clock_gettime_return - - ALIGN -syscall: /* Syscall fallback. */ - mov x8, #__NR_clock_gettime - svc #0 - ret - .cfi_endproc -ENDPROC(__kernel_clock_gettime) - -/* int __kernel_clock_getres(clockid_t clock_id, struct timespec *res); */ -ENTRY(__kernel_clock_getres) - .cfi_startproc - cmp w0, #CLOCK_REALTIME - ccmp w0, #CLOCK_MONOTONIC, #0x4, ne - ccmp w0, #CLOCK_MONOTONIC_RAW, #0x4, ne - b.ne 1f - - ldr x2, 5f - b 2f -1: - cmp w0, #CLOCK_REALTIME_COARSE - ccmp w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne - b.ne 4f - ldr x2, 6f -2: - cbz w1, 3f - stp xzr, x2, [x1] - -3: /* res == NULL. */ - mov w0, wzr - ret - -4: /* Syscall fallback. */ - mov x8, #__NR_clock_getres - svc #0 - ret -5: - .quad CLOCK_REALTIME_RES -6: - .quad CLOCK_COARSE_RES - .cfi_endproc -ENDPROC(__kernel_clock_getres) diff --git a/arch/arm64/kernel/vdso/vgettimeofday.c b/arch/arm64/kernel/vdso/vgettimeofday.c new file mode 100644 index 000000000000..b73d4011993d --- /dev/null +++ b/arch/arm64/kernel/vdso/vgettimeofday.c @@ -0,0 +1,3 @@ +#include "compiler.h" +#include "datapage.h" +#include "../../../../lib/vdso/vgettimeofday.c"