From: Michal Suchanek <msuchanek@suse.de>
To: linuxppc-dev@lists.ozlabs.org
Cc: Michal Suchanek <msuchanek@suse.de>,
Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
Michael Ellerman <mpe@ellerman.id.au>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
"David S. Miller" <davem@davemloft.net>,
Rob Herring <robh@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Jonathan Cameron <Jonathan.Cameron@huawei.com>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Christophe Leroy <christophe.leroy@c-s.fr>,
Thomas Gleixner <tglx@linutronix.de>,
Arnd Bergmann <arnd@arndb.de>, Nayna Jain <nayna@linux.ibm.com>,
Eric Richter <erichte@linux.ibm.com>,
Claudio Carvalho <cclaudio@linux.ibm.com>,
Nicholas Piggin <npiggin@gmail.com>,
Hari Bathini <hbathini@linux.ibm.com>,
Masahiro Yamada <masahiroy@kernel.org>,
Thiago Jung Bauermann <bauerman@linux.ibm.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Valentin Schneider <valentin.schneider@arm.com>,
Jordan Niethe <jniethe5@gmail.com>,
Michael Neuling <mikey@neuling.org>,
Gustavo Luiz Duarte <gustavold@linux.ibm.com>,
Allison Randal <allison@lohutok.net>,
"Eric W. Biederman" <ebiederm@xmission.com>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH v12 7/8] powerpc/perf: split callchain.c by bitness
Date: Fri, 20 Mar 2020 11:20:18 +0100 [thread overview]
Message-ID: <a20027bf1074935a7934ee2a6757c99ea047e70d.1584699455.git.msuchanek@suse.de> (raw)
In-Reply-To: <cover.1584699455.git.msuchanek@suse.de>
Building callchain.c with !COMPAT proved quite ugly with all the
defines. Splitting out the 32bit and 64bit parts looks better.
No code change intended.
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
v6:
- move current_is_64bit consolidetaion to earlier patch
- move defines to the top of callchain_32.c
- Makefile cleanup
v8:
- fix valid_user_sp
v11:
- rebase on top of def0bfdbd603
---
arch/powerpc/perf/Makefile | 5 +-
arch/powerpc/perf/callchain.c | 356 +------------------------------
arch/powerpc/perf/callchain.h | 19 ++
arch/powerpc/perf/callchain_32.c | 196 +++++++++++++++++
arch/powerpc/perf/callchain_64.c | 174 +++++++++++++++
5 files changed, 394 insertions(+), 356 deletions(-)
create mode 100644 arch/powerpc/perf/callchain.h
create mode 100644 arch/powerpc/perf/callchain_32.c
create mode 100644 arch/powerpc/perf/callchain_64.c
diff --git a/arch/powerpc/perf/Makefile b/arch/powerpc/perf/Makefile
index c155dcbb8691..53d614e98537 100644
--- a/arch/powerpc/perf/Makefile
+++ b/arch/powerpc/perf/Makefile
@@ -1,6 +1,9 @@
# SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_PERF_EVENTS) += callchain.o perf_regs.o
+obj-$(CONFIG_PERF_EVENTS) += callchain.o callchain_$(BITS).o perf_regs.o
+ifdef CONFIG_COMPAT
+obj-$(CONFIG_PERF_EVENTS) += callchain_32.o
+endif
obj-$(CONFIG_PPC_PERF_CTRS) += core-book3s.o bhrb.o
obj64-$(CONFIG_PPC_PERF_CTRS) += ppc970-pmu.o power5-pmu.o \
diff --git a/arch/powerpc/perf/callchain.c b/arch/powerpc/perf/callchain.c
index b5afd0bec4f8..dd5051015008 100644
--- a/arch/powerpc/perf/callchain.c
+++ b/arch/powerpc/perf/callchain.c
@@ -15,11 +15,9 @@
#include <asm/sigcontext.h>
#include <asm/ucontext.h>
#include <asm/vdso.h>
-#ifdef CONFIG_COMPAT
-#include "../kernel/ppc32.h"
-#endif
#include <asm/pte-walk.h>
+#include "callchain.h"
/*
* Is sp valid as the address of the next kernel stack frame after prev_sp?
@@ -102,358 +100,6 @@ perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *re
}
}
-static inline bool invalid_user_sp(unsigned long sp)
-{
- unsigned long mask = is_32bit_task() ? 3 : 7;
- unsigned long top = STACK_TOP - (is_32bit_task() ? 16 : 32);
-
- return (!sp || (sp & mask) || (sp > top));
-}
-
-#ifdef CONFIG_PPC64
-/*
- * On 64-bit we don't want to invoke hash_page on user addresses from
- * interrupt context, so if the access faults, we read the page tables
- * to find which page (if any) is mapped and access it directly.
- */
-static int read_user_stack_slow(void __user *ptr, void *buf, int nb)
-{
- int ret = -EFAULT;
- pgd_t *pgdir;
- pte_t *ptep, pte;
- unsigned shift;
- unsigned long addr = (unsigned long) ptr;
- unsigned long offset;
- unsigned long pfn, flags;
- void *kaddr;
-
- pgdir = current->mm->pgd;
- if (!pgdir)
- return -EFAULT;
-
- local_irq_save(flags);
- ptep = find_current_mm_pte(pgdir, addr, NULL, &shift);
- if (!ptep)
- goto err_out;
- if (!shift)
- shift = PAGE_SHIFT;
-
- /* align address to page boundary */
- offset = addr & ((1UL << shift) - 1);
-
- pte = READ_ONCE(*ptep);
- if (!pte_present(pte) || !pte_user(pte))
- goto err_out;
- pfn = pte_pfn(pte);
- if (!page_is_ram(pfn))
- goto err_out;
-
- /* no highmem to worry about here */
- kaddr = pfn_to_kaddr(pfn);
- memcpy(buf, kaddr + offset, nb);
- ret = 0;
-err_out:
- local_irq_restore(flags);
- return ret;
-}
-
-static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret)
-{
- if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned long) ||
- ((unsigned long)ptr & 7))
- return -EFAULT;
-
- if (!probe_user_read(ret, ptr, sizeof(*ret)))
- return 0;
-
- return read_user_stack_slow(ptr, ret, 8);
-}
-
-/*
- * 64-bit user processes use the same stack frame for RT and non-RT signals.
- */
-struct signal_frame_64 {
- char dummy[__SIGNAL_FRAMESIZE];
- struct ucontext uc;
- unsigned long unused[2];
- unsigned int tramp[6];
- struct siginfo *pinfo;
- void *puc;
- struct siginfo info;
- char abigap[288];
-};
-
-static int is_sigreturn_64_address(unsigned long nip, unsigned long fp)
-{
- if (nip == fp + offsetof(struct signal_frame_64, tramp))
- return 1;
- if (vdso64_rt_sigtramp && current->mm->context.vdso_base &&
- nip == current->mm->context.vdso_base + vdso64_rt_sigtramp)
- return 1;
- return 0;
-}
-
-/*
- * Do some sanity checking on the signal frame pointed to by sp.
- * We check the pinfo and puc pointers in the frame.
- */
-static int sane_signal_64_frame(unsigned long sp)
-{
- struct signal_frame_64 __user *sf;
- unsigned long pinfo, puc;
-
- sf = (struct signal_frame_64 __user *) sp;
- if (read_user_stack_64((unsigned long __user *) &sf->pinfo, &pinfo) ||
- read_user_stack_64((unsigned long __user *) &sf->puc, &puc))
- return 0;
- return pinfo == (unsigned long) &sf->info &&
- puc == (unsigned long) &sf->uc;
-}
-
-static void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry,
- struct pt_regs *regs)
-{
- unsigned long sp, next_sp;
- unsigned long next_ip;
- unsigned long lr;
- long level = 0;
- struct signal_frame_64 __user *sigframe;
- unsigned long __user *fp, *uregs;
-
- next_ip = perf_instruction_pointer(regs);
- lr = regs->link;
- sp = regs->gpr[1];
- perf_callchain_store(entry, next_ip);
-
- while (entry->nr < entry->max_stack) {
- fp = (unsigned long __user *) sp;
- if (invalid_user_sp(sp) || read_user_stack_64(fp, &next_sp))
- return;
- if (level > 0 && read_user_stack_64(&fp[2], &next_ip))
- return;
-
- /*
- * Note: the next_sp - sp >= signal frame size check
- * is true when next_sp < sp, which can happen when
- * transitioning from an alternate signal stack to the
- * normal stack.
- */
- if (next_sp - sp >= sizeof(struct signal_frame_64) &&
- (is_sigreturn_64_address(next_ip, sp) ||
- (level <= 1 && is_sigreturn_64_address(lr, sp))) &&
- sane_signal_64_frame(sp)) {
- /*
- * This looks like an signal frame
- */
- sigframe = (struct signal_frame_64 __user *) sp;
- uregs = sigframe->uc.uc_mcontext.gp_regs;
- if (read_user_stack_64(&uregs[PT_NIP], &next_ip) ||
- read_user_stack_64(&uregs[PT_LNK], &lr) ||
- read_user_stack_64(&uregs[PT_R1], &sp))
- return;
- level = 0;
- perf_callchain_store_context(entry, PERF_CONTEXT_USER);
- perf_callchain_store(entry, next_ip);
- continue;
- }
-
- if (level == 0)
- next_ip = lr;
- perf_callchain_store(entry, next_ip);
- ++level;
- sp = next_sp;
- }
-}
-
-#else /* CONFIG_PPC64 */
-static int read_user_stack_slow(void __user *ptr, void *buf, int nb)
-{
- return 0;
-}
-
-static inline void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry,
- struct pt_regs *regs)
-{
-}
-
-#define __SIGNAL_FRAMESIZE32 __SIGNAL_FRAMESIZE
-#define sigcontext32 sigcontext
-#define mcontext32 mcontext
-#define ucontext32 ucontext
-#define compat_siginfo_t struct siginfo
-
-#endif /* CONFIG_PPC64 */
-
-#if defined(CONFIG_PPC32) || defined(CONFIG_COMPAT)
-/*
- * On 32-bit we just access the address and let hash_page create a
- * HPTE if necessary, so there is no need to fall back to reading
- * the page tables. Since this is called at interrupt level,
- * do_page_fault() won't treat a DSI as a page fault.
- */
-static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
-{
- int rc;
-
- if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) ||
- ((unsigned long)ptr & 3))
- return -EFAULT;
-
- rc = probe_user_read(ret, ptr, sizeof(*ret));
-
- if (IS_ENABLED(CONFIG_PPC64) && rc)
- return read_user_stack_slow(ptr, ret, 4);
-
- return rc;
-}
-
-/*
- * Layout for non-RT signal frames
- */
-struct signal_frame_32 {
- char dummy[__SIGNAL_FRAMESIZE32];
- struct sigcontext32 sctx;
- struct mcontext32 mctx;
- int abigap[56];
-};
-
-/*
- * Layout for RT signal frames
- */
-struct rt_signal_frame_32 {
- char dummy[__SIGNAL_FRAMESIZE32 + 16];
- compat_siginfo_t info;
- struct ucontext32 uc;
- int abigap[56];
-};
-
-static int is_sigreturn_32_address(unsigned int nip, unsigned int fp)
-{
- if (nip == fp + offsetof(struct signal_frame_32, mctx.mc_pad))
- return 1;
- if (vdso32_sigtramp && current->mm->context.vdso_base &&
- nip == current->mm->context.vdso_base + vdso32_sigtramp)
- return 1;
- return 0;
-}
-
-static int is_rt_sigreturn_32_address(unsigned int nip, unsigned int fp)
-{
- if (nip == fp + offsetof(struct rt_signal_frame_32,
- uc.uc_mcontext.mc_pad))
- return 1;
- if (vdso32_rt_sigtramp && current->mm->context.vdso_base &&
- nip == current->mm->context.vdso_base + vdso32_rt_sigtramp)
- return 1;
- return 0;
-}
-
-static int sane_signal_32_frame(unsigned int sp)
-{
- struct signal_frame_32 __user *sf;
- unsigned int regs;
-
- sf = (struct signal_frame_32 __user *) (unsigned long) sp;
- if (read_user_stack_32((unsigned int __user *) &sf->sctx.regs, ®s))
- return 0;
- return regs == (unsigned long) &sf->mctx;
-}
-
-static int sane_rt_signal_32_frame(unsigned int sp)
-{
- struct rt_signal_frame_32 __user *sf;
- unsigned int regs;
-
- sf = (struct rt_signal_frame_32 __user *) (unsigned long) sp;
- if (read_user_stack_32((unsigned int __user *) &sf->uc.uc_regs, ®s))
- return 0;
- return regs == (unsigned long) &sf->uc.uc_mcontext;
-}
-
-static unsigned int __user *signal_frame_32_regs(unsigned int sp,
- unsigned int next_sp, unsigned int next_ip)
-{
- struct mcontext32 __user *mctx = NULL;
- struct signal_frame_32 __user *sf;
- struct rt_signal_frame_32 __user *rt_sf;
-
- /*
- * Note: the next_sp - sp >= signal frame size check
- * is true when next_sp < sp, for example, when
- * transitioning from an alternate signal stack to the
- * normal stack.
- */
- if (next_sp - sp >= sizeof(struct signal_frame_32) &&
- is_sigreturn_32_address(next_ip, sp) &&
- sane_signal_32_frame(sp)) {
- sf = (struct signal_frame_32 __user *) (unsigned long) sp;
- mctx = &sf->mctx;
- }
-
- if (!mctx && next_sp - sp >= sizeof(struct rt_signal_frame_32) &&
- is_rt_sigreturn_32_address(next_ip, sp) &&
- sane_rt_signal_32_frame(sp)) {
- rt_sf = (struct rt_signal_frame_32 __user *) (unsigned long) sp;
- mctx = &rt_sf->uc.uc_mcontext;
- }
-
- if (!mctx)
- return NULL;
- return mctx->mc_gregs;
-}
-
-static void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry,
- struct pt_regs *regs)
-{
- unsigned int sp, next_sp;
- unsigned int next_ip;
- unsigned int lr;
- long level = 0;
- unsigned int __user *fp, *uregs;
-
- next_ip = perf_instruction_pointer(regs);
- lr = regs->link;
- sp = regs->gpr[1];
- perf_callchain_store(entry, next_ip);
-
- while (entry->nr < entry->max_stack) {
- fp = (unsigned int __user *) (unsigned long) sp;
- if (invalid_user_sp(sp) || read_user_stack_32(fp, &next_sp))
- return;
- if (level > 0 && read_user_stack_32(&fp[1], &next_ip))
- return;
-
- uregs = signal_frame_32_regs(sp, next_sp, next_ip);
- if (!uregs && level <= 1)
- uregs = signal_frame_32_regs(sp, next_sp, lr);
- if (uregs) {
- /*
- * This looks like an signal frame, so restart
- * the stack trace with the values in it.
- */
- if (read_user_stack_32(&uregs[PT_NIP], &next_ip) ||
- read_user_stack_32(&uregs[PT_LNK], &lr) ||
- read_user_stack_32(&uregs[PT_R1], &sp))
- return;
- level = 0;
- perf_callchain_store_context(entry, PERF_CONTEXT_USER);
- perf_callchain_store(entry, next_ip);
- continue;
- }
-
- if (level == 0)
- next_ip = lr;
- perf_callchain_store(entry, next_ip);
- ++level;
- sp = next_sp;
- }
-}
-#else /* 32bit */
-static void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry,
- struct pt_regs *regs)
-{}
-#endif /* 32bit */
-
void
perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs)
{
diff --git a/arch/powerpc/perf/callchain.h b/arch/powerpc/perf/callchain.h
new file mode 100644
index 000000000000..7a2cb9e1181a
--- /dev/null
+++ b/arch/powerpc/perf/callchain.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _POWERPC_PERF_CALLCHAIN_H
+#define _POWERPC_PERF_CALLCHAIN_H
+
+int read_user_stack_slow(void __user *ptr, void *buf, int nb);
+void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs);
+void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs);
+
+static inline bool invalid_user_sp(unsigned long sp)
+{
+ unsigned long mask = is_32bit_task() ? 3 : 7;
+ unsigned long top = STACK_TOP - (is_32bit_task() ? 16 : 32);
+
+ return (!sp || (sp & mask) || (sp > top));
+}
+
+#endif /* _POWERPC_PERF_CALLCHAIN_H */
diff --git a/arch/powerpc/perf/callchain_32.c b/arch/powerpc/perf/callchain_32.c
new file mode 100644
index 000000000000..8aa951003141
--- /dev/null
+++ b/arch/powerpc/perf/callchain_32.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Performance counter callchain support - powerpc architecture code
+ *
+ * Copyright © 2009 Paul Mackerras, IBM Corporation.
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/perf_event.h>
+#include <linux/percpu.h>
+#include <linux/uaccess.h>
+#include <linux/mm.h>
+#include <asm/ptrace.h>
+#include <asm/pgtable.h>
+#include <asm/sigcontext.h>
+#include <asm/ucontext.h>
+#include <asm/vdso.h>
+#include <asm/pte-walk.h>
+
+#include "callchain.h"
+
+#ifdef CONFIG_PPC64
+#include "../kernel/ppc32.h"
+#else /* CONFIG_PPC64 */
+
+#define __SIGNAL_FRAMESIZE32 __SIGNAL_FRAMESIZE
+#define sigcontext32 sigcontext
+#define mcontext32 mcontext
+#define ucontext32 ucontext
+#define compat_siginfo_t struct siginfo
+
+#endif /* CONFIG_PPC64 */
+
+/*
+ * On 32-bit we just access the address and let hash_page create a
+ * HPTE if necessary, so there is no need to fall back to reading
+ * the page tables. Since this is called at interrupt level,
+ * do_page_fault() won't treat a DSI as a page fault.
+ */
+static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
+{
+ int rc;
+
+ if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) ||
+ ((unsigned long)ptr & 3))
+ return -EFAULT;
+
+ rc = probe_user_read(ret, ptr, sizeof(*ret));
+
+ if (IS_ENABLED(CONFIG_PPC64) && rc)
+ return read_user_stack_slow(ptr, ret, 4);
+
+ return rc;
+}
+
+/*
+ * Layout for non-RT signal frames
+ */
+struct signal_frame_32 {
+ char dummy[__SIGNAL_FRAMESIZE32];
+ struct sigcontext32 sctx;
+ struct mcontext32 mctx;
+ int abigap[56];
+};
+
+/*
+ * Layout for RT signal frames
+ */
+struct rt_signal_frame_32 {
+ char dummy[__SIGNAL_FRAMESIZE32 + 16];
+ compat_siginfo_t info;
+ struct ucontext32 uc;
+ int abigap[56];
+};
+
+static int is_sigreturn_32_address(unsigned int nip, unsigned int fp)
+{
+ if (nip == fp + offsetof(struct signal_frame_32, mctx.mc_pad))
+ return 1;
+ if (vdso32_sigtramp && current->mm->context.vdso_base &&
+ nip == current->mm->context.vdso_base + vdso32_sigtramp)
+ return 1;
+ return 0;
+}
+
+static int is_rt_sigreturn_32_address(unsigned int nip, unsigned int fp)
+{
+ if (nip == fp + offsetof(struct rt_signal_frame_32,
+ uc.uc_mcontext.mc_pad))
+ return 1;
+ if (vdso32_rt_sigtramp && current->mm->context.vdso_base &&
+ nip == current->mm->context.vdso_base + vdso32_rt_sigtramp)
+ return 1;
+ return 0;
+}
+
+static int sane_signal_32_frame(unsigned int sp)
+{
+ struct signal_frame_32 __user *sf;
+ unsigned int regs;
+
+ sf = (struct signal_frame_32 __user *) (unsigned long) sp;
+ if (read_user_stack_32((unsigned int __user *) &sf->sctx.regs, ®s))
+ return 0;
+ return regs == (unsigned long) &sf->mctx;
+}
+
+static int sane_rt_signal_32_frame(unsigned int sp)
+{
+ struct rt_signal_frame_32 __user *sf;
+ unsigned int regs;
+
+ sf = (struct rt_signal_frame_32 __user *) (unsigned long) sp;
+ if (read_user_stack_32((unsigned int __user *) &sf->uc.uc_regs, ®s))
+ return 0;
+ return regs == (unsigned long) &sf->uc.uc_mcontext;
+}
+
+static unsigned int __user *signal_frame_32_regs(unsigned int sp,
+ unsigned int next_sp, unsigned int next_ip)
+{
+ struct mcontext32 __user *mctx = NULL;
+ struct signal_frame_32 __user *sf;
+ struct rt_signal_frame_32 __user *rt_sf;
+
+ /*
+ * Note: the next_sp - sp >= signal frame size check
+ * is true when next_sp < sp, for example, when
+ * transitioning from an alternate signal stack to the
+ * normal stack.
+ */
+ if (next_sp - sp >= sizeof(struct signal_frame_32) &&
+ is_sigreturn_32_address(next_ip, sp) &&
+ sane_signal_32_frame(sp)) {
+ sf = (struct signal_frame_32 __user *) (unsigned long) sp;
+ mctx = &sf->mctx;
+ }
+
+ if (!mctx && next_sp - sp >= sizeof(struct rt_signal_frame_32) &&
+ is_rt_sigreturn_32_address(next_ip, sp) &&
+ sane_rt_signal_32_frame(sp)) {
+ rt_sf = (struct rt_signal_frame_32 __user *) (unsigned long) sp;
+ mctx = &rt_sf->uc.uc_mcontext;
+ }
+
+ if (!mctx)
+ return NULL;
+ return mctx->mc_gregs;
+}
+
+void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs)
+{
+ unsigned int sp, next_sp;
+ unsigned int next_ip;
+ unsigned int lr;
+ long level = 0;
+ unsigned int __user *fp, *uregs;
+
+ next_ip = perf_instruction_pointer(regs);
+ lr = regs->link;
+ sp = regs->gpr[1];
+ perf_callchain_store(entry, next_ip);
+
+ while (entry->nr < entry->max_stack) {
+ fp = (unsigned int __user *) (unsigned long) sp;
+ if (invalid_user_sp(sp) || read_user_stack_32(fp, &next_sp))
+ return;
+ if (level > 0 && read_user_stack_32(&fp[1], &next_ip))
+ return;
+
+ uregs = signal_frame_32_regs(sp, next_sp, next_ip);
+ if (!uregs && level <= 1)
+ uregs = signal_frame_32_regs(sp, next_sp, lr);
+ if (uregs) {
+ /*
+ * This looks like an signal frame, so restart
+ * the stack trace with the values in it.
+ */
+ if (read_user_stack_32(&uregs[PT_NIP], &next_ip) ||
+ read_user_stack_32(&uregs[PT_LNK], &lr) ||
+ read_user_stack_32(&uregs[PT_R1], &sp))
+ return;
+ level = 0;
+ perf_callchain_store_context(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, next_ip);
+ continue;
+ }
+
+ if (level == 0)
+ next_ip = lr;
+ perf_callchain_store(entry, next_ip);
+ ++level;
+ sp = next_sp;
+ }
+}
diff --git a/arch/powerpc/perf/callchain_64.c b/arch/powerpc/perf/callchain_64.c
new file mode 100644
index 000000000000..df1ffd8b20f2
--- /dev/null
+++ b/arch/powerpc/perf/callchain_64.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Performance counter callchain support - powerpc architecture code
+ *
+ * Copyright © 2009 Paul Mackerras, IBM Corporation.
+ */
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/perf_event.h>
+#include <linux/percpu.h>
+#include <linux/uaccess.h>
+#include <linux/mm.h>
+#include <asm/ptrace.h>
+#include <asm/pgtable.h>
+#include <asm/sigcontext.h>
+#include <asm/ucontext.h>
+#include <asm/vdso.h>
+#include <asm/pte-walk.h>
+
+#include "callchain.h"
+
+/*
+ * On 64-bit we don't want to invoke hash_page on user addresses from
+ * interrupt context, so if the access faults, we read the page tables
+ * to find which page (if any) is mapped and access it directly.
+ */
+int read_user_stack_slow(void __user *ptr, void *buf, int nb)
+{
+ int ret = -EFAULT;
+ pgd_t *pgdir;
+ pte_t *ptep, pte;
+ unsigned int shift;
+ unsigned long addr = (unsigned long) ptr;
+ unsigned long offset;
+ unsigned long pfn, flags;
+ void *kaddr;
+
+ pgdir = current->mm->pgd;
+ if (!pgdir)
+ return -EFAULT;
+
+ local_irq_save(flags);
+ ptep = find_current_mm_pte(pgdir, addr, NULL, &shift);
+ if (!ptep)
+ goto err_out;
+ if (!shift)
+ shift = PAGE_SHIFT;
+
+ /* align address to page boundary */
+ offset = addr & ((1UL << shift) - 1);
+
+ pte = READ_ONCE(*ptep);
+ if (!pte_present(pte) || !pte_user(pte))
+ goto err_out;
+ pfn = pte_pfn(pte);
+ if (!page_is_ram(pfn))
+ goto err_out;
+
+ /* no highmem to worry about here */
+ kaddr = pfn_to_kaddr(pfn);
+ memcpy(buf, kaddr + offset, nb);
+ ret = 0;
+err_out:
+ local_irq_restore(flags);
+ return ret;
+}
+
+static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret)
+{
+ if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned long) ||
+ ((unsigned long)ptr & 7))
+ return -EFAULT;
+
+ if (!probe_user_read(ret, ptr, sizeof(*ret)))
+ return 0;
+
+ return read_user_stack_slow(ptr, ret, 8);
+}
+
+/*
+ * 64-bit user processes use the same stack frame for RT and non-RT signals.
+ */
+struct signal_frame_64 {
+ char dummy[__SIGNAL_FRAMESIZE];
+ struct ucontext uc;
+ unsigned long unused[2];
+ unsigned int tramp[6];
+ struct siginfo *pinfo;
+ void *puc;
+ struct siginfo info;
+ char abigap[288];
+};
+
+static int is_sigreturn_64_address(unsigned long nip, unsigned long fp)
+{
+ if (nip == fp + offsetof(struct signal_frame_64, tramp))
+ return 1;
+ if (vdso64_rt_sigtramp && current->mm->context.vdso_base &&
+ nip == current->mm->context.vdso_base + vdso64_rt_sigtramp)
+ return 1;
+ return 0;
+}
+
+/*
+ * Do some sanity checking on the signal frame pointed to by sp.
+ * We check the pinfo and puc pointers in the frame.
+ */
+static int sane_signal_64_frame(unsigned long sp)
+{
+ struct signal_frame_64 __user *sf;
+ unsigned long pinfo, puc;
+
+ sf = (struct signal_frame_64 __user *) sp;
+ if (read_user_stack_64((unsigned long __user *) &sf->pinfo, &pinfo) ||
+ read_user_stack_64((unsigned long __user *) &sf->puc, &puc))
+ return 0;
+ return pinfo == (unsigned long) &sf->info &&
+ puc == (unsigned long) &sf->uc;
+}
+
+void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry,
+ struct pt_regs *regs)
+{
+ unsigned long sp, next_sp;
+ unsigned long next_ip;
+ unsigned long lr;
+ long level = 0;
+ struct signal_frame_64 __user *sigframe;
+ unsigned long __user *fp, *uregs;
+
+ next_ip = perf_instruction_pointer(regs);
+ lr = regs->link;
+ sp = regs->gpr[1];
+ perf_callchain_store(entry, next_ip);
+
+ while (entry->nr < entry->max_stack) {
+ fp = (unsigned long __user *) sp;
+ if (invalid_user_sp(sp) || read_user_stack_64(fp, &next_sp))
+ return;
+ if (level > 0 && read_user_stack_64(&fp[2], &next_ip))
+ return;
+
+ /*
+ * Note: the next_sp - sp >= signal frame size check
+ * is true when next_sp < sp, which can happen when
+ * transitioning from an alternate signal stack to the
+ * normal stack.
+ */
+ if (next_sp - sp >= sizeof(struct signal_frame_64) &&
+ (is_sigreturn_64_address(next_ip, sp) ||
+ (level <= 1 && is_sigreturn_64_address(lr, sp))) &&
+ sane_signal_64_frame(sp)) {
+ /*
+ * This looks like an signal frame
+ */
+ sigframe = (struct signal_frame_64 __user *) sp;
+ uregs = sigframe->uc.uc_mcontext.gp_regs;
+ if (read_user_stack_64(&uregs[PT_NIP], &next_ip) ||
+ read_user_stack_64(&uregs[PT_LNK], &lr) ||
+ read_user_stack_64(&uregs[PT_R1], &sp))
+ return;
+ level = 0;
+ perf_callchain_store_context(entry, PERF_CONTEXT_USER);
+ perf_callchain_store(entry, next_ip);
+ continue;
+ }
+
+ if (level == 0)
+ next_ip = lr;
+ perf_callchain_store(entry, next_ip);
+ ++level;
+ sp = next_sp;
+ }
+}
--
2.23.0
next prev parent reply other threads:[~2020-03-20 10:20 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20200225173541.1549955-1-npiggin@gmail.com>
2020-03-19 12:19 ` [PATCH v11 0/8] Disable compat cruft on ppc64le v11 Michal Suchanek
2020-03-19 12:19 ` [PATCH v11 1/8] powerpc: Add back __ARCH_WANT_SYS_LLSEEK macro Michal Suchanek
2020-03-19 12:19 ` [PATCH v11 2/8] powerpc: move common register copy functions from signal_32.c to signal.c Michal Suchanek
2020-03-19 12:19 ` [PATCH v11 3/8] powerpc/perf: consolidate read_user_stack_32 Michal Suchanek
2020-03-24 8:48 ` Nicholas Piggin
2020-03-24 19:38 ` Michal Suchánek
2020-04-03 7:13 ` Nicholas Piggin
2020-04-03 10:52 ` Michal Suchánek
2020-04-03 11:26 ` Nicholas Piggin
2020-04-03 11:51 ` Michal Suchánek
2020-04-06 20:52 ` Michal Suchánek
2020-04-06 21:00 ` [PATCH] powerpcs: perf: consolidate perf_callchain_user_64 and perf_callchain_user_32 Michal Suchanek
2020-04-07 5:21 ` Christophe Leroy
2020-04-09 11:22 ` Michal Suchánek
2020-03-19 12:19 ` [PATCH v11 4/8] powerpc/perf: consolidate valid_user_sp Michal Suchanek
2020-03-19 12:19 ` [PATCH v11 5/8] powerpc/64: make buildable without CONFIG_COMPAT Michal Suchanek
2020-03-24 8:54 ` Nicholas Piggin
2020-03-24 19:30 ` Michal Suchánek
2020-04-03 7:16 ` Nicholas Piggin
2020-03-19 12:19 ` [PATCH v11 6/8] powerpc/64: Make COMPAT user-selectable disabled on littleendian by default Michal Suchanek
2020-03-19 12:19 ` [PATCH v11 7/8] powerpc/perf: split callchain.c by bitness Michal Suchanek
2020-03-19 12:19 ` [PATCH v11 8/8] MAINTAINERS: perf: Add pattern that matches ppc perf to the perf entry Michal Suchanek
2020-03-19 13:37 ` Andy Shevchenko
2020-03-19 14:00 ` Michal Suchánek
2020-03-19 14:26 ` Andy Shevchenko
2020-03-19 17:03 ` Joe Perches
2020-03-19 12:36 ` [PATCH v11 0/8] Disable compat cruft on ppc64le v11 Christophe Leroy
2020-03-19 14:01 ` Michal Suchánek
2020-04-03 7:25 ` Nicholas Piggin
2020-04-03 7:26 ` Christophe Leroy
2020-04-03 9:43 ` Nicholas Piggin
2020-04-05 0:40 ` Michael Ellerman
2020-03-20 10:20 ` [PATCH v12 0/8] Disable compat cruft on ppc64le v12 Michal Suchanek
2020-03-20 10:20 ` [PATCH v12 1/8] powerpc: Add back __ARCH_WANT_SYS_LLSEEK macro Michal Suchanek
2020-03-20 10:20 ` [PATCH v12 2/8] powerpc: move common register copy functions from signal_32.c to signal.c Michal Suchanek
2020-03-20 10:20 ` [PATCH v12 3/8] powerpc/perf: consolidate read_user_stack_32 Michal Suchanek
2020-03-20 10:20 ` [PATCH v12 4/8] powerpc/perf: consolidate valid_user_sp -> invalid_user_sp Michal Suchanek
2020-03-20 10:20 ` [PATCH v12 5/8] powerpc/64: make buildable without CONFIG_COMPAT Michal Suchanek
2020-04-07 5:50 ` Christophe Leroy
2020-04-07 9:57 ` Michal Suchánek
2020-03-20 10:20 ` [PATCH v12 6/8] powerpc/64: Make COMPAT user-selectable disabled on littleendian by default Michal Suchanek
2020-03-20 10:20 ` Michal Suchanek [this message]
2020-03-20 10:20 ` [PATCH v12 8/8] MAINTAINERS: perf: Add pattern that matches ppc perf to the perf entry Michal Suchanek
2020-03-20 10:33 ` Andy Shevchenko
2020-03-20 11:23 ` Michal Suchánek
2020-03-20 12:42 ` Andy Shevchenko
2020-03-20 14:42 ` Joe Perches
2020-03-20 16:28 ` Michal Suchánek
2020-03-20 16:31 ` Andy Shevchenko
2020-03-20 16:42 ` Michal Suchánek
2020-03-20 16:47 ` Andy Shevchenko
2020-03-20 21:36 ` Joe Perches
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=a20027bf1074935a7934ee2a6757c99ea047e70d.1584699455.git.msuchanek@suse.de \
--to=msuchanek@suse.de \
--cc=Jonathan.Cameron@huawei.com \
--cc=acme@kernel.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=allison@lohutok.net \
--cc=andriy.shevchenko@linux.intel.com \
--cc=arnd@arndb.de \
--cc=bauerman@linux.ibm.com \
--cc=benh@kernel.crashing.org \
--cc=bigeasy@linutronix.de \
--cc=cclaudio@linux.ibm.com \
--cc=christophe.leroy@c-s.fr \
--cc=davem@davemloft.net \
--cc=ebiederm@xmission.com \
--cc=erichte@linux.ibm.com \
--cc=gregkh@linuxfoundation.org \
--cc=gustavold@linux.ibm.com \
--cc=hbathini@linux.ibm.com \
--cc=jniethe5@gmail.com \
--cc=jolsa@redhat.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mark.rutland@arm.com \
--cc=masahiroy@kernel.org \
--cc=mchehab+huawei@kernel.org \
--cc=mikey@neuling.org \
--cc=mingo@redhat.com \
--cc=mpe@ellerman.id.au \
--cc=namhyung@kernel.org \
--cc=nayna@linux.ibm.com \
--cc=npiggin@gmail.com \
--cc=paulus@samba.org \
--cc=peterz@infradead.org \
--cc=robh@kernel.org \
--cc=tglx@linutronix.de \
--cc=valentin.schneider@arm.com \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).