perf/arch/x86: Implement hw_breakpoint_arch_parse()

Migrate to the new API in order to remove arch_validate_hwbkpt_settings()
that clumsily mixes up architecture validation and commit.

Original-patch-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joel Fernandes <joel.opensrc@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/1529981939-8231-4-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/hw_breakpoint.h b/arch/x86/include/asm/hw_breakpoint.h
index 78924596f51f472a6033bb2fcfaf4a877fe42845..6c88e8e22678fe4536eda440e33383ab243b04b6 100644 (file)
--- a/arch/x86/include/asm/hw_breakpoint.h
+++ b/arch/x86/include/asm/hw_breakpoint.h
@@ -49,11 +49,15 @@ static inline int hw_breakpoint_slots(int type)
        return HBP_NUM;
 }
 
+struct perf_event_attr;
 struct perf_event;
 struct pmu;
 
 extern int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw);
-extern int arch_validate_hwbkpt_settings(struct perf_event *bp);
+extern int hw_breakpoint_arch_parse(struct perf_event *bp,
+                                   const struct perf_event_attr *attr,
+                                   struct arch_hw_breakpoint *hw);
+#define hw_breakpoint_arch_parse hw_breakpoint_arch_parse
 extern int hw_breakpoint_exceptions_notify(struct notifier_block *unused,
                                           unsigned long val, void *data);
 

diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index c43379188f4ff0bf878a4d133658634f91141920..34a5c171514870af79195679ad9bb90741a57992 100644 (file)
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -239,19 +239,20 @@ int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
        return (va >= TASK_SIZE_MAX) || ((va + len - 1) >= TASK_SIZE_MAX);
 }
 
-static int arch_build_bp_info(struct perf_event *bp)
+static int arch_build_bp_info(struct perf_event *bp,
+                             const struct perf_event_attr *attr,
+                             struct arch_hw_breakpoint *hw)
 {
-       struct arch_hw_breakpoint *info = counter_arch_bp(bp);
-
-       info->address = bp->attr.bp_addr;
+       hw->address = attr->bp_addr;
+       hw->mask = 0;
 
        /* Type */
-       switch (bp->attr.bp_type) {
+       switch (attr->bp_type) {
        case HW_BREAKPOINT_W:
-               info->type = X86_BREAKPOINT_WRITE;
+               hw->type = X86_BREAKPOINT_WRITE;
                break;
        case HW_BREAKPOINT_W | HW_BREAKPOINT_R:
-               info->type = X86_BREAKPOINT_RW;
+               hw->type = X86_BREAKPOINT_RW;
                break;
        case HW_BREAKPOINT_X:
                /*
@@ -259,23 +260,23 @@ static int arch_build_bp_info(struct perf_event *bp)
                 * acceptable for kprobes.  On non-kprobes kernels, we don't
                 * allow kernel breakpoints at all.
                 */
-               if (bp->attr.bp_addr >= TASK_SIZE_MAX) {
+               if (attr->bp_addr >= TASK_SIZE_MAX) {
 #ifdef CONFIG_KPROBES
-                       if (within_kprobe_blacklist(bp->attr.bp_addr))
+                       if (within_kprobe_blacklist(attr->bp_addr))
                                return -EINVAL;
 #else
                        return -EINVAL;
 #endif
                }
 
-               info->type = X86_BREAKPOINT_EXECUTE;
+               hw->type = X86_BREAKPOINT_EXECUTE;
                /*
                 * x86 inst breakpoints need to have a specific undefined len.
                 * But we still need to check userspace is not trying to setup
                 * an unsupported length, to get a range breakpoint for example.
                 */
-               if (bp->attr.bp_len == sizeof(long)) {
-                       info->len = X86_BREAKPOINT_LEN_X;
+               if (attr->bp_len == sizeof(long)) {
+                       hw->len = X86_BREAKPOINT_LEN_X;
                        return 0;
                }
        default:
@@ -283,28 +284,26 @@ static int arch_build_bp_info(struct perf_event *bp)
        }
 
        /* Len */
-       info->mask = 0;
-
-       switch (bp->attr.bp_len) {
+       switch (attr->bp_len) {
        case HW_BREAKPOINT_LEN_1:
-               info->len = X86_BREAKPOINT_LEN_1;
+               hw->len = X86_BREAKPOINT_LEN_1;
                break;
        case HW_BREAKPOINT_LEN_2:
-               info->len = X86_BREAKPOINT_LEN_2;
+               hw->len = X86_BREAKPOINT_LEN_2;
                break;
        case HW_BREAKPOINT_LEN_4:
-               info->len = X86_BREAKPOINT_LEN_4;
+               hw->len = X86_BREAKPOINT_LEN_4;
                break;
 #ifdef CONFIG_X86_64
        case HW_BREAKPOINT_LEN_8:
-               info->len = X86_BREAKPOINT_LEN_8;
+               hw->len = X86_BREAKPOINT_LEN_8;
                break;
 #endif
        default:
                /* AMD range breakpoint */
-               if (!is_power_of_2(bp->attr.bp_len))
+               if (!is_power_of_2(attr->bp_len))
                        return -EINVAL;
-               if (bp->attr.bp_addr & (bp->attr.bp_len - 1))
+               if (attr->bp_addr & (attr->bp_len - 1))
                        return -EINVAL;
 
                if (!boot_cpu_has(X86_FEATURE_BPEXT))
@@ -317,8 +316,8 @@ static int arch_build_bp_info(struct perf_event *bp)
                 * breakpoints, then we'll have to check for kprobe-blacklisted
                 * addresses anywhere in the range.
                 */
-               info->mask = bp->attr.bp_len - 1;
-               info->len = X86_BREAKPOINT_LEN_1;
+               hw->mask = attr->bp_len - 1;
+               hw->len = X86_BREAKPOINT_LEN_1;
        }
 
        return 0;
@@ -327,22 +326,23 @@ static int arch_build_bp_info(struct perf_event *bp)
 /*
  * Validate the arch-specific HW Breakpoint register settings
  */
-int arch_validate_hwbkpt_settings(struct perf_event *bp)
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+                            const struct perf_event_attr *attr,
+                            struct arch_hw_breakpoint *hw)
 {
-       struct arch_hw_breakpoint *info = counter_arch_bp(bp);
        unsigned int align;
        int ret;
 
 
-       ret = arch_build_bp_info(bp);
+       ret = arch_build_bp_info(bp, attr, hw);
        if (ret)
                return ret;
 
-       switch (info->len) {
+       switch (hw->len) {
        case X86_BREAKPOINT_LEN_1:
                align = 0;
-               if (info->mask)
-                       align = info->mask;
+               if (hw->mask)
+                       align = hw->mask;
                break;
        case X86_BREAKPOINT_LEN_2:
                align = 1;
@@ -363,7 +363,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
         * Check that the low-order bits of the address are appropriate
         * for the alignment implied by len.
         */
-       if (info->address & align)
+       if (hw->address & align)
                return -EINVAL;
 
        return 0;