This patch contains the first part of the new generic files.
--- linux-2.6.17-rc4.orig/lib/carta_random32.c 1969-12-31 16:00:00.000000000 -0800
+++ linux-2.6.17-rc4/lib/carta_random32.c 2006-05-12 03:18:52.000000000 -0700
@@ -0,0 +1,29 @@
+/*
+ * Fast, simple, yet decent quality random number generator based on
+ * a paper by David G. Carta ("Two Fast Implementations of the
+ * `Minimal Standard' Random Number Generator," Communications of the
+ * ACM, January, 1990).
+ *
+ * Copyright (c) 2002-2005 Hewlett-Packard Development Company, L.P.
+ * Contributed by David Mosberger-Tang <[email protected]>
+ */
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/perfmon.h>
+
+#ifndef __HAVE_ARCH_CARTA_RANDOM32
+u64 carta_random32 (u64 seed)
+{
+# define A 16807
+# define M ((u32) 1 << 31)
+ u64 s, prod = A * seed, p, q;
+
+ p = (prod >> 31) & (M - 1);
+ q = (prod >> 0) & (M - 1);
+ s = p + q;
+ if (s >= M)
+ s -= M - 1;
+ return s;
+}
+EXPORT_SYMBOL(carta_random32);
+#endif
--- linux-2.6.17-rc4.orig/perfmon/Makefile 1969-12-31 16:00:00.000000000 -0800
+++ linux-2.6.17-rc4/perfmon/Makefile 2006-05-12 03:18:52.000000000 -0700
@@ -0,0 +1,7 @@
+#
+# Copyright (c) 2005-2006 Hewlett-Packard Development Company, L.P.
+# Contributed by Stephane Eranian <[email protected]>
+#
+obj-$(CONFIG_PERFMON) = perfmon.o perfmon_res.o perfmon_fmt.o perfmon_pmu.o \
+ perfmon_sysfs.o perfmon_syscalls.o perfmon_file.o perfmon_ctxsw.o \
+ perfmon_intr.o perfmon_dfl_smpl.o
--- linux-2.6.17-rc4.orig/perfmon/perfmon.c 1969-12-31 16:00:00.000000000 -0800
+++ linux-2.6.17-rc4/perfmon/perfmon.c 2006-05-12 03:18:52.000000000 -0700
@@ -0,0 +1,3249 @@
+/*
+ * perfmon.c: perfmon2 core functions
+ *
+ * This file implements the perfmon2 interface which
+ * provides access to the hardware performance counters
+ * of the host processor.
+ *
+ * The initial version of perfmon.c was written by
+ * Ganesh Venkitachalam, IBM Corp.
+ *
+ * Then it was modified for perfmon-1.x by Stephane Eranian and
+ * David Mosberger, Hewlett Packard Co.
+ *
+ * Version Perfmon-2.x is a complete rewrite of perfmon-1.x
+ * by Stephane Eranian, Hewlett Packard Co.
+ *
+ * Copyright (c) 1999-2006 Hewlett-Packard Development Company, L.P.
+ * Contributed by Stephane Eranian <[email protected]>
+ * David Mosberger-Tang <[email protected]>
+ *
+ * More information about perfmon available at:
+ * http://www.hpl.hp.com/research/linux/perfmon
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/vmalloc.h>
+#include <linux/sysctl.h>
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/vfs.h>
+#include <linux/pagemap.h>
+#include <linux/mount.h>
+#include <linux/perfmon.h>
+
+/*
+ * internal variables
+ */
+static kmem_cache_t *pfm_ctx_cachep;
+static kmem_cache_t *pfm_lg_set_cachep;
+static kmem_cache_t *pfm_set_cachep;
+
+
+/*
+ * external variables
+ */
+
+DEFINE_PER_CPU(unsigned long, pfm_syst_info);
+DEFINE_PER_CPU(struct task_struct *, pmu_owner);
+DEFINE_PER_CPU(struct pfm_context *, pmu_ctx);
+DEFINE_PER_CPU(u64, pmu_activation_number);
+DEFINE_PER_CPU(struct pfm_stats, pfm_stats);
+
+#define PFM_INVALID_ACTIVATION ((u64)~0)
+
+/*
+ * Reset PMD register flags
+ */
+#define PFM_PMD_RESET_NONE 0 /* do not reset (pfm_switch_set) */
+#define PFM_PMD_RESET_SHORT 1 /* use short reset value */
+#define PFM_PMD_RESET_LONG 2 /* use long reset value */
+
+/* forward declaration */
+static int pfm_end_notify_user(struct pfm_context *ctx);
+int pfm_ovfl_notify_user(struct pfm_context *ctx,
+ struct pfm_event_set *set,
+ unsigned long ip);
+
+
+static union pfm_msg *pfm_get_new_msg(struct pfm_context *ctx)
+{
+ int idx, next;
+
+ next = (ctx->msgq_tail+1) % PFM_MAX_MSGS;
+
+ PFM_DBG("head=%d tail=%d", ctx->msgq_head, ctx->msgq_tail);
+
+ if (next == ctx->msgq_head)
+ return NULL;
+
+ idx = ctx->msgq_tail;
+ ctx->msgq_tail = next;
+
+ PFM_DBG("head=%d tail=%d msg=%d",
+ ctx->msgq_head,
+ ctx->msgq_tail, idx);
+
+ return ctx->msgq+idx;
+}
+
+static inline void pfm_reset_msgq(struct pfm_context *ctx)
+{
+ ctx->msgq_head = ctx->msgq_tail = 0;
+}
+
+
+void pfm_context_free(struct pfm_context *ctx)
+{
+ struct pfm_event_set *set, *tmp = NULL;
+ kmem_cache_t *cachep;
+ struct pfm_smpl_fmt *fmt;
+ int use_remap;
+
+ use_remap = ctx->flags.mapset;
+ fmt = ctx->smpl_fmt;
+
+ if (use_remap)
+ cachep = pfm_set_cachep;
+ else
+ cachep = pfm_lg_set_cachep;
+
+ /* free all sets */
+ for (set = ctx->sets; set; set = tmp) {
+ tmp = set->next;
+ if (use_remap)
+ vfree(set->view);
+ kmem_cache_free(cachep, set);
+ }
+
+ if (ctx->smpl_addr) {
+ PFM_DBG("freeing sampling buffer @%p size=%zu",
+ ctx->smpl_addr,
+ ctx->smpl_size);
+
+ pfm_release_buf_space(ctx->smpl_size);
+
+ if (fmt->fmt_exit)
+ (*fmt->fmt_exit)(ctx->smpl_addr);
+
+ vfree(ctx->smpl_addr);
+ }
+
+ PFM_DBG("free ctx @%p", ctx);
+ kmem_cache_free(pfm_ctx_cachep, ctx);
+
+ /*
+ * decrease refcount on:
+ * - PMU description table
+ * - sampling format
+ */
+ pfm_pmu_conf_put();
+ pfm_smpl_fmt_put(fmt);
+}
+
+/*
+ * only called in for the current task
+ */
+static int pfm_setup_smpl_fmt(struct pfm_smpl_fmt *fmt, void *fmt_arg,
+ struct pfm_context *ctx, u32 ctx_flags,
+ int compat_mode, struct file *filp)
+{
+ size_t size = 0;
+ int ret = 0;
+
+ /*
+ * validate parameters
+ */
+ if (fmt->fmt_validate) {
+ ret = (*fmt->fmt_validate)(ctx_flags, pfm_pmu_conf->num_pmds,
+ fmt_arg);
+ PFM_DBG("validate(0x%x,%p)=%d", ctx_flags, fmt_arg, ret);
+ if (ret)
+ goto error;
+ }
+
+ /*
+ * check if buffer format wants to use perfmon
+ * buffer allocation/mapping service
+ */
+ size = 0;
+ if (fmt->fmt_getsize) {
+ ret = (*fmt->fmt_getsize)(ctx_flags, fmt_arg, &size);
+ if (ret) {
+ PFM_DBG("cannot get size ret=%d", ret);
+ goto error;
+ }
+ }
+
+ if (size) {
+#ifdef CONFIG_IA64_PERFMON_COMPAT
+ if (compat_mode == PFM_COMPAT)
+ ret = pfm_smpl_buffer_alloc_old(ctx, size, filp);
+ else
+#endif
+ {
+ ret = pfm_smpl_buffer_alloc(ctx, size);
+ }
+ if (ret)
+ goto error;
+
+ }
+
+ if (fmt->fmt_init) {
+ ret = (*fmt->fmt_init)(ctx, ctx->smpl_addr, ctx_flags,
+ pfm_pmu_conf->num_pmds,
+ fmt_arg);
+ if (ret)
+ goto error_buffer;
+ }
+ return 0;
+
+error_buffer:
+ pfm_release_buf_space(ctx->smpl_size);
+ /*
+ * we do not call fmt_exit, if init has failed
+ */
+ vfree(ctx->smpl_addr);
+error:
+ return ret;
+}
+
+/*
+ * this function does not modify the next field
+ */
+static void pfm_init_evtset(struct pfm_event_set *set)
+{
+ u64 *impl_pmcs;
+ u16 i, max_pmc;
+
+ max_pmc = pfm_pmu_conf->max_pmc;
+ impl_pmcs = pfm_pmu_conf->impl_pmcs;
+
+ /*
+ * install default values for all PMC registers
+ */
+ for (i=0; i < max_pmc; i++) {
+ if (pfm_bv_isset(impl_pmcs, i)) {
+ set->pmcs[i] = pfm_pmu_conf->pmc_desc[i].default_value;
+ PFM_DBG("set %u pmc%u=0x%llx",
+ set->id,
+ i,
+ (unsigned long long)set->pmcs[i]);
+ }
+ }
+
+ /*
+ * PMD registers are set to 0 when the event set is allocated,
+ * hence we do not need to explicitely initialize them.
+ *
+ * For virtual PMD registers (i.e., those tied to a SW resource)
+ * their value becomes meaningful once the context is attached.
+ */
+}
+
+struct pfm_event_set *pfm_find_set(struct pfm_context *ctx, u16 set_id,
+ int alloc)
+{
+ kmem_cache_t *cachep;
+ struct pfm_event_set *set, *prev;
+ size_t view_size;
+ void *view;
+
+ /*
+ * shortcut for set 0: always exist, cannot be removed
+ */
+ if (set_id == 0 && alloc == 0)
+ return ctx->sets;
+
+ prev = NULL;
+
+ for (set = ctx->sets; set; set = set->next) {
+
+ if (set->id == set_id)
+ return set;
+ if (set->id > set_id)
+ break;
+ prev = set;
+ }
+ if (alloc == 0)
+ return NULL;
+
+ cachep = ctx->flags.mapset ? pfm_set_cachep : pfm_lg_set_cachep;
+
+ set = kmem_cache_alloc(cachep, SLAB_ATOMIC);
+ if (set) {
+ memset(set, 0, sizeof(*set));
+
+ if (ctx->flags.mapset) {
+ view_size = PAGE_ALIGN(sizeof(struct pfm_set_view));
+ view = vmalloc(view_size);
+ if (view == NULL) {
+ PFM_DBG("cannot allocate set view");
+ kmem_cache_free(cachep, set);
+ return NULL;
+ }
+ } else {
+ view_size = sizeof(struct pfm_set_view);
+ view = (struct pfm_set_view *)(set+1);
+ }
+
+ memset(view, 0, sizeof(struct pfm_set_view));
+
+ set->id = set_id;
+ set->view = view;
+ set->mmap_offset = PFM_SET_REMAP_BASE
+ + (set_id*PFM_SET_REMAP_SCALAR);
+
+ pfm_init_evtset(set);
+
+ if (prev) {
+ set->next = prev->next;
+ prev->next = set;
+ } else {
+ ctx->sets = ctx->active_set = set;
+ set->view->set_status = PFM_SETVFL_ACTIVE;
+ }
+
+ PFM_DBG("set_id=%u size=%zu view=%p remap=%d mmap_offs=%lu",
+ set_id,
+ view_size,
+ view,
+ ctx->flags.mapset,
+ set->mmap_offset);
+ }
+ return set;
+}
+
+void pfm_mask_monitoring(struct pfm_context *ctx)
+{
+ struct pfm_event_set *set;
+ u64 now_itc;
+ int is_system;
+
+ PFM_DBG_ovfl("masking monitoring");
+
+ now_itc = pfm_arch_get_itc();
+ is_system = ctx->flags.system;
+ set = ctx->active_set;
+
+ /*
+ * monitoring can only be masked as a result of a valid
+ * counter overflow. In UP and per-thread mode,
+ * it is possible that the current task may not be the
+ * one that generated the overflow because the overflow happen
+ * very close to the context switch point where interrupts are
+ * masked. In SMP per-thread, current is always the task that
+ * generated the overflow.
+ *
+ * For system-wide, the current task is alwys the one that
+ * generated the overflow.
+ *
+ * In any case, accessing the PMU directly is always safe
+ * given that we are only called from the overflow handler.
+ */
+ pfm_modview_begin(set);
+ pfm_arch_save_pmds(ctx, set);
+ pfm_modview_end(set);
+ pfm_arch_mask_monitoring(ctx);
+
+ /*
+ * accumulate the set duration up to this point
+ */
+ set->duration += now_itc - set->duration_start;
+}
+
+/*
+ * interrupts are masked when entering this function.
+ * context must be in MASKED state when calling.
+ */
+static void pfm_unmask_monitoring(struct pfm_context *ctx)
+{
+ struct pfm_event_set *set;
+ u64 now_itc;
+
+ if (ctx->state != PFM_CTX_MASKED)
+ return;
+
+ PFM_DBG("unmasking monitoring");
+
+ set = ctx->active_set;
+
+ /*
+ * must be done before calling
+ * pfm_arch_unmask_monitoring()
+ */
+ ctx->state = PFM_CTX_LOADED;
+
+ pfm_arch_restore_pmds(ctx, set);
+
+ pfm_arch_unmask_monitoring(ctx);
+
+ now_itc = pfm_arch_get_itc();
+
+ set->priv_flags &= ~PFM_SETFL_PRIV_MOD_BOTH;
+
+ /*
+ * reset set duration timer
+ */
+ set->duration_start = now_itc;
+}
+
+#ifdef CONFIG_SMP
+/*
+ * this function is exclusively called from pfm_close().
+ * The context is not protected at that time, nor are interrupts
+ * on the remote CPU. That's necessary to avoid deadlocks.
+ */
+static void pfm_syswide_force_stop(void *info)
+{
+ struct pfm_context *ctx = info;
+ unsigned long flags;
+ int ret;
+
+ /* On some platforms smp_call_function_single() is not
+ * implemented and we use a broadcast IPI instead. In
+ * this case, we need ignore the call on all but the
+ * actual target as indicated by cpu.
+ */
+ if (ctx->cpu != smp_processor_id()) {
+ PFM_ERR("%s for CPU%u but on CPU%d",
+ __FUNCTION__,
+ ctx->cpu,
+ smp_processor_id());
+ return;
+ }
+
+ if (__get_cpu_var(pmu_ctx) != ctx) {
+ PFM_ERR("%s CPU%d unexpected ctx %p instead of %p",
+ __FUNCTION__,
+ smp_processor_id(),
+ __get_cpu_var(pmu_ctx), ctx);
+ return;
+ }
+
+ PFM_DBG("forcing CPU-wide stop");
+
+ /*
+ * the context is already protected in pfm_close(), we simply
+ * need to mask interrupts to avoid a PMU interrupt race on
+ * this CPU
+ */
+ local_irq_save(flags);
+
+ /*
+ * defer calling pfm_release_session() to avoid possible
+ * deadlock caused by nesting of smp_call()
+ */
+ ret = __pfm_unload_context(ctx, 1);
+ if (ret) {
+ PFM_ERR("%s: context_unload returned %d",
+ __FUNCTION__, ret);
+ }
+
+ /*
+ * unmask interrupts, PMU interrupts are now spurious here
+ */
+ local_irq_restore(flags);
+}
+
+void pfm_syswide_cleanup_other_cpu(struct pfm_context *ctx)
+{
+ int ret = 0;
+ int ctx_cpu;
+
+ /*
+ * grab a cpu, it is detroyed by __pfm_unload_context()
+ */
+ ctx_cpu = ctx->cpu;
+
+ PFM_DBG("calling CPU%u for cleanup", ctx_cpu);
+
+ ret = smp_call_function_single(ctx_cpu, pfm_syswide_force_stop,
+ ctx, 0, 1);
+
+ /*
+ * we defer releasing the session until we are back from the
+ * remote cleanup routine because there may be situations where
+ * the release_session() may need to nest another smp_call()
+ * which would lead to a deadlock.
+ */
+ pfm_release_session(ctx, ctx_cpu);
+
+ PFM_DBG("called CPU%u for cleanup ret=%d", ctx_cpu, ret);
+}
+
+#endif /* CONFIG_SMP */
+
+struct pfm_context *pfm_context_alloc(void)
+{
+ struct pfm_context *ctx;
+
+ /*
+ * allocate context structure
+ * the architecture specific portion is allocated
+ * right after the struct pfm_context struct. It is
+ * accessible at ctx_arch = (ctx+1)
+ */
+ ctx = kmem_cache_alloc(pfm_ctx_cachep, SLAB_ATOMIC);
+ if (ctx) {
+ memset(ctx, 0, sizeof(*ctx)+PFM_ARCH_CTX_SIZE);
+ PFM_DBG("alloc ctx @%p", ctx);
+ }
+ return ctx;
+}
+
+/*
+ * in new mode, we only allocate the kernel buffer, an explicit mmap()
+ * is needed to remap the buffer at the user level
+ */
+int pfm_smpl_buffer_alloc(struct pfm_context *ctx, size_t rsize)
+{
+ void *addr;
+ size_t size;
+ int ret;
+
+ /*
+ * the fixed header + requested size and align to page boundary
+ */
+ size = PAGE_ALIGN(rsize);
+
+ PFM_DBG("sampling buffer rsize=%zu size=%zu", rsize, size);
+
+ ret = pfm_reserve_buf_space(size);
+ if (ret) return ret;
+
+ addr = vmalloc(size);
+ if (addr == NULL) {
+ PFM_DBG("cannot allocate sampling buffer");
+ goto unres;
+ }
+
+ memset(addr, 0, size);
+
+ //pfm_get_map(addr, size);
+
+ ctx->smpl_addr = addr;
+ ctx->smpl_size = size;
+
+ PFM_DBG("kernel smpl buffer @%p", addr);
+
+ return 0;
+unres:
+ pfm_release_buf_space(size);
+ return -ENOMEM;
+}
+
+static inline u64 pfm_new_pmd_value (struct pfm_pmd *reg, int reset_mode)
+{
+ u64 val, mask;
+ u64 new_seed, old_seed;
+
+ val = reset_mode == PFM_PMD_RESET_LONG ? reg->long_reset : reg->short_reset;
+ old_seed = reg->seed;
+ mask = reg->mask;
+
+ if (reg->flags & PFM_REGFL_RANDOM) {
+ new_seed = carta_random32(old_seed);
+
+ /* counter values are negative numbers! */
+ val -= (old_seed & mask);
+ if ((mask >> 32) != 0)
+ /* construct a full 64-bit random value: */
+ new_seed |= (u64)carta_random32((u32)(old_seed >> 32)) << 32;
+ reg->seed = new_seed;
+ }
+ reg->lval = val;
+ return val;
+}
+
+void pfm_reset_pmds(struct pfm_context *ctx, struct pfm_event_set *set,
+ int reset_mode)
+{
+ u64 ovfl_mask, hw_val;
+ u64 *cnt_mask, *reset_pmds;
+ u64 val;
+ unsigned int i, max_pmd, not_masked;
+
+ reset_pmds = set->reset_pmds;
+ max_pmd = pfm_pmu_conf->max_pmd;
+
+ if (bitmap_empty(ulp(reset_pmds), max_pmd)) return;
+
+ ovfl_mask = pfm_pmu_conf->ovfl_mask;
+ cnt_mask = pfm_pmu_conf->cnt_pmds;
+ not_masked = ctx->state != PFM_CTX_MASKED;
+
+ PFM_DBG_ovfl("%s r_pmds=0x%llx not_masked=%d",
+ reset_mode == PFM_PMD_RESET_LONG ? "long" : "short",
+ (unsigned long long)reset_pmds[0],
+ not_masked);
+
+ pfm_modview_begin(set);
+
+ for (i = 0; i < max_pmd; i++) {
+
+ if (pfm_bv_isset(reset_pmds, i)) {
+
+ val = pfm_new_pmd_value(set->pmds + i,
+ reset_mode);
+
+ set->view->set_pmds[i]= val;
+
+ if (not_masked) {
+ if (pfm_bv_isset(cnt_mask, i)) {
+ hw_val = val & ovfl_mask;
+ } else {
+ hw_val = val;
+ }
+ pfm_write_pmd(ctx, i, hw_val);
+ }
+ PFM_DBG_ovfl("pmd%u set=%u sval=0x%llx",
+ i,
+ set->id,
+ (unsigned long long)val);
+ }
+ }
+
+ pfm_modview_end(set);
+
+ /*
+ * done with reset
+ */
+ bitmap_zero(ulp(reset_pmds), max_pmd);
+
+ /*
+ * make changes visible
+ */
+ if (not_masked)
+ pfm_arch_serialize();
+}
+
+/*
+ * reload reference overflow switch thresholds
+ */
+static void pfm_reload_switch_thresholds(struct pfm_event_set *set)
+{
+ u64 *mask;
+ u16 i, max_cnt_pmd, first_cnt_pmd;
+
+ mask = set->used_pmds;
+ first_cnt_pmd = pfm_pmu_conf->first_cnt_pmd;
+ max_cnt_pmd = pfm_pmu_conf->max_cnt_pmd;
+
+ for (i = first_cnt_pmd; i< max_cnt_pmd; i++) {
+ if (pfm_bv_isset(mask, i)) {
+ set->pmds[i].ovflsw_thres = set->pmds[i].ovflsw_ref_thres;
+ PFM_DBG("pmd%u set=%u ovflsw_thres=%llu",
+ i,
+ set->id,
+ (unsigned long long)set->pmds[i].ovflsw_thres);
+ }
+ }
+}
+
+/*
+ *
+ * always operating on the current task
+ *
+ * input:
+ * - new_set: new set to switch to, if NULL follow normal chain
+ */
+void pfm_switch_sets(struct pfm_context *ctx,
+ struct pfm_event_set *new_set,
+ int reset_mode,
+ int no_restart)
+{
+ struct pfm_event_set *set;
+ u64 switch_count;
+ u64 now_itc, end_itc;
+ unsigned long info = 0;
+ u32 new_flags;
+ u16 max_pmd;
+ int is_system, state, is_active;
+
+ now_itc = pfm_arch_get_itc();
+ set = ctx->active_set;
+ max_pmd = pfm_pmu_conf->max_pmd;
+ is_active = ctx->flags.started || pfm_arch_is_active(ctx);
+
+ BUG_ON(ctx->flags.system == 0 && ctx->task != current);
+
+ /*
+ * if no set is explicitely requested,
+ * use the set_switch_next field
+ */
+ if (new_set == NULL) {
+ /*
+ * we use round-robin unless the user specified
+ * a particular set to go to.
+ */
+ new_set = set->switch_next;
+ if (new_set == NULL)
+ new_set = ctx->sets;
+ }
+
+ PFM_DBG("state=%d prev_set=%u prev_runs=%llu new_set=%u "
+ "new_runs=%llu reset_mode=%d",
+ ctx->state,
+ set->id,
+ (unsigned long long)set->view->set_runs,
+ new_set->id,
+ (unsigned long long)new_set->view->set_runs,
+ reset_mode);
+
+ /*
+ * nothing more to do
+ */
+ if (new_set == set)
+ return;
+
+ is_system = ctx->flags.system;
+ state = ctx->state;
+ new_flags = new_set->flags;
+ switch_count = __get_cpu_var(pfm_stats).pfm_set_switch_count;
+
+ pfm_modview_begin(set);
+
+ new_set->view->set_runs++;
+
+ if (is_active) {
+ /*
+ * stop current set
+ */
+ if (is_system)
+ info = __get_cpu_var(pfm_syst_info);
+
+ pfm_arch_stop(current, ctx, set);
+
+ pfm_arch_save_pmds(ctx, set);
+
+ /*
+ * compute elapsed cycles for active set
+ */
+ set->duration += now_itc - set->duration_start;
+ set->view->set_status &= ~PFM_SETVFL_ACTIVE;
+
+ }
+ pfm_modview_end(set);
+
+ switch_count++;
+
+ pfm_arch_restore_pmds(ctx, new_set);
+
+ /*
+ * if masked, we must restore the pmcs such that they
+ * do not capture anything.
+ */
+ pfm_arch_restore_pmcs(ctx, new_set);
+
+ new_set->priv_flags &= ~PFM_SETFL_PRIV_MOD_BOTH;
+
+ /*
+ * reload switch threshold
+ */
+ if (new_flags & PFM_SETFL_OVFL_SWITCH)
+ pfm_reload_switch_thresholds(new_set);
+
+ /*
+ * reset timeout for new set
+ */
+ if (new_flags & PFM_SETFL_TIME_SWITCH)
+ new_set->timeout = new_set->switch_timeout;
+
+ /*
+ * reset overflowed PMD registers
+ */
+ if (reset_mode != PFM_PMD_RESET_NONE)
+ pfm_reset_pmds(ctx, new_set, reset_mode);
+
+ /*
+ * this is needed when coming from pfm_start()
+ */
+ if (no_restart)
+ goto skip_restart;
+
+ /*
+ * reactivate monitoring
+ */
+ if (is_system) {
+ info &= ~PFM_CPUINFO_TIME_SWITCH;
+
+ if (new_flags & PFM_SETFL_TIME_SWITCH)
+ info |= PFM_CPUINFO_TIME_SWITCH;
+
+ __get_cpu_var(pfm_syst_info) = info;
+
+ PFM_DBG("new_set=%u info=0x%lx flags=0x%x",
+ new_set->id,
+ info,
+ new_flags);
+
+ if (is_active && (current->pid != 0 || (new_flags & PFM_SETFL_EXCL_IDLE) == 0))
+ pfm_arch_start(current, ctx, new_set);
+ } else {
+ if (is_active)
+ pfm_arch_start(current, ctx, new_set);
+ }
+
+ if (is_active)
+ new_set->duration_start = now_itc;
+
+skip_restart:
+ end_itc = pfm_arch_get_itc();
+ ctx->active_set = new_set;
+ new_set->view->set_status |= PFM_SETVFL_ACTIVE;
+
+ __get_cpu_var(pfm_stats).pfm_set_switch_count = switch_count;
+ __get_cpu_var(pfm_stats).pfm_set_switch_cycles += end_itc - now_itc;
+}
+
+/*
+ * called from pfm_handle_work() and __pfm_restart()
+ * for system-wide and per-thread context.
+ */
+void pfm_resume_after_ovfl(struct pfm_context *ctx)
+{
+ struct pfm_smpl_fmt *fmt;
+ u32 rst_ctrl;
+ struct pfm_event_set *set;
+ u64 *reset_pmds;
+ void *hdr;
+ int max_cnt_pmd;
+ int state, ret;
+
+ hdr = ctx->smpl_addr;
+ fmt = ctx->smpl_fmt;
+ state = ctx->state;
+ set = ctx->active_set;
+ ret = 0;
+
+ max_cnt_pmd = pfm_pmu_conf->max_cnt_pmd;
+
+ if (hdr) {
+ rst_ctrl = 0;
+ prefetch(hdr);
+ if (fmt->fmt_restart)
+ ret = (*fmt->fmt_restart)(state == PFM_CTX_LOADED,
+ &rst_ctrl, hdr);
+ } else {
+ rst_ctrl= PFM_OVFL_CTRL_RESET;
+ }
+ reset_pmds = set->reset_pmds;
+
+ PFM_DBG("restart=%d r_pmds=0x%llx switch=%d ctx_state=%d",
+ ret,
+ (unsigned long long)reset_pmds[0],
+ (set->priv_flags & PFM_SETFL_PRIV_SWITCH) != 0,
+ state);
+
+ if (ret == 0) {
+ /*
+ * switch set if needed
+ */
+ if (set->priv_flags & PFM_SETFL_PRIV_SWITCH) {
+ set->priv_flags &= ~PFM_SETFL_PRIV_SWITCH;
+ pfm_switch_sets(ctx, NULL, PFM_PMD_RESET_LONG, 0);
+ set = ctx->active_set;
+ } else if (rst_ctrl & PFM_OVFL_CTRL_RESET) {
+ pfm_reset_pmds(ctx, set, PFM_PMD_RESET_LONG);
+ }
+
+ if ((rst_ctrl & PFM_OVFL_CTRL_MASK) == 0) {
+ pfm_unmask_monitoring(ctx);
+ } else {
+ PFM_DBG("stopping monitoring?");
+ }
+ ctx->state = PFM_CTX_LOADED;
+ }
+ ctx->flags.can_restart = 0;
+}
+
+
+/*
+ * ensures that all id_next sets exists such that the round-robin
+ * will work correctly, i.e., next dangling references.
+ */
+int pfm_prepare_sets(struct pfm_context *ctx)
+{
+ struct pfm_event_set *set1, *set2;
+ int max_cnt_pmd;
+
+ max_cnt_pmd = pfm_pmu_conf->max_cnt_pmd;
+
+ for (set1 = ctx->sets; set1; set1 = set1->next) {
+ set2 = set1->next;
+ /*
+ * switch_next is used during actual switching
+ * so we prepare its value here. When no explicit next
+ * is requested, the field is initialized with the address
+ * of the next element in the ordered list
+ */
+ if (set1->flags & PFM_SETFL_EXPL_NEXT) {
+ for (set2 = ctx->sets; set2; set2 = set2->next) {
+ if (set2->id == set1->id_next)
+ break;
+ }
+ if (set2 == NULL) {
+ PFM_DBG("set%u points to set%u "
+ "which does not exist",
+ set1->id,
+ set1->id_next);
+ return -EINVAL;
+ }
+ }
+ /*
+ * update field used during actual switching
+ */
+ set1->switch_next = set2;
+
+ /*
+ * cleanup bitvectors
+ */
+ bitmap_zero(ulp(set1->ovfl_pmds), max_cnt_pmd);
+ bitmap_zero(ulp(set1->povfl_pmds), max_cnt_pmd);
+ set1->npend_ovfls = 0;
+ /*
+ * we cannot just use plain clear because of arch-specific flags
+ */
+ set1->priv_flags &= ~(PFM_SETFL_PRIV_MOD_BOTH|PFM_SETFL_PRIV_SWITCH);
+
+ /*
+ * reset activation and elapsed cycles
+ */
+ set1->duration = 0;
+
+ pfm_modview_begin(set1);
+
+ set1->view->set_runs = 0;
+
+ pfm_modview_end(set1);
+ }
+ return 0;
+}
+
+/*
+ * save all used pmds and release PMU ownership
+ *
+ * context is locked (not needed in UP) and interrupts
+ * are masked
+ *
+ * owner task is not necessarily current task in UP
+ */
+void pfm_save_pmds_release(struct pfm_context *ctx)
+{
+ struct pfm_event_set *set;
+
+ set = ctx->active_set;
+
+ pfm_modview_begin(set);
+ pfm_arch_save_pmds(ctx, set);
+ pfm_modview_end(set);
+
+ pfm_set_pmu_owner(NULL, NULL);
+ PFM_DBG("released ownership");
+}
+
+/*
+ * This function is always called after pfm_stop has been issued
+ */
+void pfm_flush_pmds(struct task_struct *task, struct pfm_context *ctx)
+{
+ struct pfm_event_set *set;
+ u64 ovfl_mask;
+ u64 *ovfl_pmds;
+ int max_pmd, max_cnt_pmd, first_cnt_pmd;
+ unsigned int i, can_access_pmu;
+ u32 num_ovfls;
+
+ ovfl_mask = pfm_pmu_conf->ovfl_mask;
+ max_pmd = pfm_pmu_conf->max_pmd;
+ first_cnt_pmd = pfm_pmu_conf->first_cnt_pmd;
+ max_cnt_pmd = pfm_pmu_conf->max_cnt_pmd;
+
+ set = ctx->active_set;
+
+ /*
+ * for system-wide, guaranteed to run on correct CPU
+ */
+ can_access_pmu = (__get_cpu_var(pmu_owner) == task) || ctx->flags.system;
+
+ if (can_access_pmu) {
+ /*
+ * pending overflows have been saved by pfm_stop()
+ */
+ pfm_save_pmds_release(ctx);
+ }
+
+ PFM_DBG("access_pmu=%d active_set=%u", can_access_pmu, set->id);
+
+ /*
+ * cleanup each set
+ */
+ for (set = ctx->sets; set; set = set->next) {
+
+ /*
+ * only look at sets with pending overflows
+ */
+ if (set->npend_ovfls == 0) continue;
+
+ pfm_modview_begin(set);
+
+ /*
+ * take care of overflow
+ * no format handler is called here
+ */
+ ovfl_pmds = set->povfl_pmds;
+ num_ovfls = set->npend_ovfls;
+
+ PFM_DBG("set%u first=%u novfls=%u",
+ set->id, first_cnt_pmd, num_ovfls);
+ /*
+ * only look up to the last counting PMD register
+ */
+ for (i = first_cnt_pmd; num_ovfls; i++) {
+
+ if (pfm_bv_isset(set->used_pmds, i)) {
+
+ if (pfm_bv_isset(ovfl_pmds, i)) {
+ set->view->set_pmds[i] += 1 + ovfl_mask;
+ num_ovfls--;
+ PFM_DBG("pmd%u overflowed", i);
+ }
+
+ PFM_DBG("pmd%u set=%u val=0x%llx",
+ i,
+ set->id,
+ (unsigned long long)set->view->set_pmds[i]);
+ }
+ }
+ pfm_modview_end(set);
+ }
+}
+
+
+
+/*
+ * called only from exit_thread(): task == current
+ * we come here only if current has a context
+ * attached (loaded or masked or zombie)
+ */
+void __pfm_exit_thread(struct task_struct *task)
+{
+ struct pfm_context *ctx;
+ unsigned long flags;
+ int free_ok = 0;
+
+ ctx = task->pfm_context;
+
+ BUG_ON(ctx->flags.system);
+
+ spin_lock_irqsave(&ctx->lock, flags);
+
+ PFM_DBG("state=%d", ctx->state);
+
+ /*
+ * __pfm_unload_context() cannot fail
+ * in the context states we are interested in
+ */
+ switch(ctx->state) {
+ case PFM_CTX_LOADED:
+ case PFM_CTX_MASKED:
+ __pfm_unload_context(ctx, 0);
+ pfm_end_notify_user(ctx);
+ break;
+ case PFM_CTX_ZOMBIE:
+ __pfm_unload_context(ctx, 0);
+ free_ok = 1;
+ break;
+ default:
+ BUG_ON(ctx->state != PFM_CTX_LOADED);
+ break;
+ }
+ spin_unlock_irqrestore(&ctx->lock, flags);
+
+ /*
+ * All memory free operations (especially for vmalloc'ed memory)
+ * MUST be done with interrupts ENABLED.
+ */
+ if (free_ok)
+ pfm_context_free(ctx);
+}
+
+struct pfm_context * pfm_get_ctx(int fd)
+{
+ struct file *filp;
+ struct pfm_context *ctx;
+
+ filp = fget(fd);
+ if (unlikely(filp == NULL)) {
+ PFM_DBG("invalid fd %d", fd);
+ return NULL;
+ }
+
+ if (unlikely(pfm_is_fd(filp) == 0)) {
+ PFM_DBG("fd %d not related to perfmon", fd);
+ fput(filp);
+ return NULL;
+ }
+ ctx = filp->private_data;
+
+ /*
+ * sanity check
+ */
+ if (filp != ctx->filp && ctx->filp) {
+ PFM_DBG("filp is different");
+ }
+
+ /*
+ * update filp
+ */
+ ctx->filp = filp;
+ return ctx;
+}
+
+
+/*
+ * pfm_handle_work() can be called with interrupts enabled
+ * (TIF_NEED_RESCHED) or disabled. The down_interruptible
+ * call may sleep, therefore we must re-enable interrupts
+ * to avoid deadlocks. It is safe to do so because this function
+ * is called ONLY when returning to user level (PUStk=1), in which case
+ * there is no risk of kernel stack overflow due to deep
+ * interrupt nesting.
+ */
+void __pfm_handle_work(void)
+{
+ struct pfm_context *ctx;
+ unsigned long flags, dummy_flags;
+ unsigned int reason;
+ int ret;
+
+ ctx = current->pfm_context;
+ if (ctx == NULL) {
+ PFM_ERR("handle_work [%d] has no ctx", current->pid);
+ return;
+ }
+
+ BUG_ON(ctx->flags.system);
+
+ spin_lock_irqsave(&ctx->lock, flags);
+
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+
+ /*
+ * extract reason for being here and clear
+ */
+ reason = ctx->flags.trap_reason;
+
+ if (reason == PFM_TRAP_REASON_NONE)
+ goto nothing_to_do;
+
+ ctx->flags.trap_reason = PFM_TRAP_REASON_NONE;
+
+ PFM_DBG("reason=%d state=%d", reason, ctx->state);
+
+ /*
+ * must be done before we check for simple-reset mode
+ */
+ if (ctx->state == PFM_CTX_ZOMBIE)
+ goto do_zombie;
+
+ if (reason == PFM_TRAP_REASON_RESET)
+ goto skip_blocking;
+
+ /*
+ * restore interrupt mask to what it was on entry.
+ * Could be enabled/diasbled.
+ */
+ spin_unlock_irqrestore(&ctx->lock, flags);
+
+ /*
+ * force interrupt enable because of down_interruptible()
+ */
+ local_irq_enable();
+
+ PFM_DBG("before block sleeping");
+
+ /*
+ * may go through without blocking on SMP systems
+ * if restart has been received already by the time we call down()
+ */
+ ret = wait_for_completion_interruptible(&ctx->restart_complete);
+
+ PFM_DBG("after block sleeping ret=%d", ret);
+
+ /*
+ * lock context and mask interrupts again
+ * We save flags into a dummy because we may have
+ * altered interrupts mask compared to entry in this
+ * function.
+ */
+ spin_lock_irqsave(&ctx->lock, dummy_flags);
+
+ if (ctx->state == PFM_CTX_ZOMBIE)
+ goto do_zombie;
+
+ /*
+ * in case of interruption of down() we don't restart anything
+ */
+ if (ret < 0)
+ goto nothing_to_do;
+
+skip_blocking:
+ pfm_resume_after_ovfl(ctx);
+
+nothing_to_do:
+
+ /*
+ * restore flags as they were upon entry
+ */
+ spin_unlock_irqrestore(&ctx->lock, flags);
+ return;
+
+do_zombie:
+ PFM_DBG("context is zombie, bailing out");
+
+ __pfm_unload_context(ctx, 0);
+
+ /*
+ * enable interrupt for vfree()
+ */
+ local_irq_enable();
+
+ /*
+ * actual context free
+ */
+ pfm_context_free(ctx);
+
+ /*
+ * restore interrupts as they were upon entry
+ */
+ local_irq_restore(flags);
+}
+
+static int pfm_notify_user(struct pfm_context *ctx, union pfm_msg *msg)
+{
+ if (ctx->state == PFM_CTX_ZOMBIE) {
+ PFM_DBG("ignoring overflow notification, owner is zombie");
+ return 0;
+ }
+
+ PFM_DBG("waking up somebody");
+
+ if (msg)
+ wake_up_interruptible(&ctx->msgq_wait);
+
+ /*
+ * it is safe to call kill_fasync() from an interrupt
+ * handler. kill_fasync() grabs two RW locks (fasync_lock,
+ * tasklist_lock) in read mode. There is conflict only in
+ * case the PMU interrupt occurs during a write mode critical
+ * section. This cannot happen becuase for both locks, the
+ * write mode is always using interrupt masking (write_lock_irq).
+ */
+ kill_fasync (&ctx->async_queue, SIGIO, POLL_IN);
+
+ return 0;
+}
+
+int pfm_ovfl_notify_user(struct pfm_context *ctx,
+ struct pfm_event_set *set,
+ unsigned long ip)
+{
+ union pfm_msg *msg = NULL;
+ int max_cnt_pmd;
+ u64 *ovfl_pmds;
+
+ max_cnt_pmd = pfm_pmu_conf->max_cnt_pmd;
+
+ if (ctx->flags.no_msg == 0) {
+ msg = pfm_get_new_msg(ctx);
+ if (msg == NULL) {
+ /*
+ * when message queue fills up it is because the user
+ * did not extract the message, yet issued
+ * pfm_restart(). At this point, we stop sending
+ * notification, thus the user will not be able to get
+ * new samples when using the default format.
+ */
+ PFM_DBG_ovfl("no more notification msgs");
+ return -1;
+ }
+
+ msg->pfm_ovfl_msg.msg_type = PFM_MSG_OVFL;
+ msg->pfm_ovfl_msg.msg_ovfl_pid = current->pid;
+ msg->pfm_ovfl_msg.msg_active_set = set->id;
+
+ ovfl_pmds = msg->pfm_ovfl_msg.msg_ovfl_pmds;
+
+ bitmap_copy(ulp(ovfl_pmds), ulp(set->ovfl_pmds),
+ max_cnt_pmd);
+
+ msg->pfm_ovfl_msg.msg_ovfl_cpu = smp_processor_id();
+ msg->pfm_ovfl_msg.msg_ovfl_tid = current->tgid;
+ msg->pfm_ovfl_msg.msg_ovfl_ip = ip;
+ }
+
+ PFM_DBG("ovfl msg: ip=0x%lx o_pmds=0x%llx",
+ ip,
+ (unsigned long long)set->ovfl_pmds[0]);
+
+ return pfm_notify_user(ctx, msg);
+}
+
+static int pfm_end_notify_user(struct pfm_context *ctx)
+{
+ union pfm_msg *msg;
+
+ msg = pfm_get_new_msg(ctx);
+ if (msg == NULL) {
+ PFM_ERR("%s no more msgs", __FUNCTION__);
+ return -1;
+ }
+ /* no leak */
+ memset(msg, 0, sizeof(*msg));
+
+ msg->type = PFM_MSG_END;
+
+ PFM_DBG("end msg: msg=%p no_msg=%d",
+ msg,
+ ctx->flags.no_msg);
+
+ return pfm_notify_user(ctx, msg);
+}
+
+/*
+ * this function is called from pfm_init()
+ * pfm_pmu_conf is NULL at this point
+ */
+void __cpuinit pfm_init_percpu (void *dummy)
+{
+ pfm_arch_init_percpu();
+}
+
+/*
+ * global initialization routine, executed only once
+ */
+int __init pfm_init(void)
+{
+ PFM_LOG("version %u.%u", PFM_VERSION_MAJ, PFM_VERSION_MIN);
+
+ pfm_ctx_cachep = kmem_cache_create("pfm_context",
+ sizeof(struct pfm_context)+PFM_ARCH_CTX_SIZE,
+ SLAB_HWCACHE_ALIGN, 0, NULL, NULL);
+ if (pfm_ctx_cachep == NULL) {
+ PFM_ERR("cannot initialize context slab");
+ goto error_disable;
+ }
+
+ pfm_lg_set_cachep = kmem_cache_create("pfm_large_event_set",
+ sizeof(struct pfm_event_set)+sizeof(struct pfm_set_view),
+ SLAB_HWCACHE_ALIGN, 0, NULL, NULL);
+ if (pfm_lg_set_cachep == NULL) {
+ PFM_ERR("cannot initialize large event set slab");
+ goto error_disable;
+ }
+
+ pfm_set_cachep = kmem_cache_create("pfm_event_set",
+ sizeof(struct pfm_event_set),
+ SLAB_HWCACHE_ALIGN, 0, NULL, NULL);
+ if (pfm_set_cachep == NULL) {
+ PFM_ERR("cannot initialize event set slab");
+ goto error_disable;
+ }
+
+ if (pfm_sysfs_init())
+ goto error_disable;
+
+ /*
+ * one time, global initialization
+ */
+ if (pfm_arch_initialize())
+ goto error_disable;
+
+ init_pfm_fs();
+
+ /*
+ * per cpu initialization (interrupts must be enabled)
+ */
+ on_each_cpu(pfm_init_percpu, NULL, 1, 1);
+
+ return 0;
+error_disable:
+ return -1;
+}
+__initcall(pfm_init);
+
+
+/*
+ * called from process.c:copy_thread(). task is new child.
+ */
+void __pfm_copy_thread(struct task_struct *task)
+{
+ PFM_DBG("clearing state for [%d]", task->pid);
+ /*
+ * cut link inherited from parent (current)
+ */
+ task->pfm_context = NULL;
+}
+
+/*
+ * called from *_timer_interrupt(). task == current
+ */
+void __pfm_handle_switch_timeout(void)
+{
+ struct pfm_event_set *set;
+ struct pfm_context *ctx;
+ unsigned long flags;
+
+ /*
+ * The timer tick check is operating on each
+ * CPU. Not all CPUs have time switching enabled
+ * hence we need to check.
+ */
+ ctx = __get_cpu_var(pmu_ctx);
+ if (ctx == NULL)
+ return;
+
+ spin_lock_irqsave(&ctx->lock, flags);
+
+ set = ctx->active_set;
+
+ /*
+ * we decrement only when attached and not masked or zombie
+ */
+ if (ctx->state != PFM_CTX_LOADED)
+ goto done;
+
+ /*
+ * do not decrement timeout unless monitoring is active.
+ */
+ if (ctx->flags.started == 0 && pfm_arch_is_active(ctx) == 0)
+ goto done;
+
+ set->timeout--;
+
+ __get_cpu_var(pfm_stats).pfm_handle_timeout_count++;
+
+ if (set->timeout == 0)
+ pfm_switch_sets(ctx, NULL, PFM_PMD_RESET_SHORT, 0);
+done:
+ spin_unlock_irqrestore(&ctx->lock, flags);
+}
+
+int __pfm_start(struct pfm_context *ctx, struct pfarg_start *start)
+{
+ struct task_struct *task, *owner_task;
+ struct pfm_event_set *new_set, *old_set;
+ u64 now_itc;
+ unsigned long info = 0;
+ int state, is_self, flags, is_new_set;
+
+ state = ctx->state;
+ task = ctx->task;
+
+ /*
+ * context must be loaded.
+ * we do not support starting while in MASKED state
+ * (mostly because of set switching issues)
+ */
+ if (state != PFM_CTX_LOADED)
+ return -EINVAL;
+
+ owner_task = __get_cpu_var(pmu_owner);
+ old_set = new_set = ctx->active_set;
+
+ is_self = ctx->flags.system || task == current;
+
+ /*
+ * always the case for system-wide
+ */
+ if (task == NULL)
+ task = current;
+ /*
+ * argument is provided?
+ */
+ if (start) {
+ /*
+ * find the set to load first
+ */
+ new_set = pfm_find_set(ctx, start->start_set, 0);
+ if (new_set == NULL) {
+ PFM_DBG("event set%u does not exist",
+ start->start_set);
+ return -EINVAL;
+ }
+ }
+ is_new_set = new_set != old_set;
+
+ PFM_DBG("cur_set=%u req_set=%u",
+ ctx->active_set->id,
+ new_set->id);
+
+ /*
+ * if we need to change the active set we need
+ * to check if we can access the PMU
+ */
+ if (is_new_set) {
+ /*
+ * system-wide: must run on the right CPU
+ * per-thread : must be the owner of the PMU context
+ *
+ * pfm_switch_sets() returns with monitoring stopped
+ */
+ if (is_self) {
+ pfm_switch_sets(ctx, new_set, PFM_PMD_RESET_LONG, 1);
+ } else {
+ /*
+ * In the case of UP kernel, the PMU may
+ * contain the state of the task we want to
+ * operate on, yet the task may be switched
+ * out (lazy save). We need to save current
+ * state (old_set), switch active_set and
+ * mark it for reload.
+ */
+ if (owner_task == task) {
+ pfm_modview_begin(old_set);
+ pfm_arch_save_pmds(ctx, old_set);
+ pfm_modview_end(old_set);
+ }
+ ctx->active_set = new_set;
+ new_set->view->set_status |= PFM_SETVFL_ACTIVE;
+ new_set->priv_flags |= PFM_SETFL_PRIV_MOD_BOTH;
+ }
+ }
+ /*
+ * mark as started, must be done before calling
+ * pfm_arch_start()
+ */
+ ctx->flags.started = 1;
+
+ /*
+ * at this point, monitoring is:
+ * - stopped if we switched set (self-monitoring)
+ * - stopped if never started
+ * - started if calling pfm_start() in sequence
+ */
+ now_itc = pfm_arch_get_itc();
+ flags = new_set->flags;
+
+ if (is_self) {
+ if (flags & PFM_SETFL_TIME_SWITCH)
+ info = PFM_CPUINFO_TIME_SWITCH;
+
+ __get_cpu_var(pfm_syst_info) = info;
+ }
+ /*
+ * in system-wide, the new_set may EXCL_IDLE, in which
+ * case pfm_start() must actually stop monitoring
+ */
+ if (current->pid == 0 && (flags & PFM_SETFL_EXCL_IDLE))
+ pfm_arch_stop(task, ctx, new_set);
+ else
+ pfm_arch_start(task, ctx, new_set);
+
+ /*
+ * we restart total duration even if context was
+ * already started. In that case, counts are simply
+ * reset.
+ *
+ * For system-wide, we start counting even when we exclude
+ * idle and pfm_start() called by idle.
+ *
+ * For per-thread, if not self-monitoring, the statement
+ * below will have no effect because thread is stopped.
+ * The field is reset of ctxsw in.
+ *
+ * if monitoring is masked (MASKED), this statement
+ * will be overriden in pfm_unmask_monitoring()
+ */
+ ctx->duration_start = now_itc;
+ new_set->duration_start = now_itc;
+
+
+ return 0;
+}
+
+int __pfm_stop(struct pfm_context *ctx)
+{
+ struct pfm_event_set *set;
+ struct task_struct *task;
+ u64 now_itc;
+ int state, is_system;
+
+ now_itc = pfm_arch_get_itc();
+ state = ctx->state;
+ is_system = ctx->flags.system;
+ set = ctx->active_set;
+
+ /*
+ * context must be attached (zombie cannot happen)
+ */
+ if (state == PFM_CTX_UNLOADED)
+ return -EINVAL;
+
+ task = ctx->task;
+
+ PFM_DBG("ctx_task=[%d] ctx_state=%d is_system=%d",
+ task ? task->pid : -1,
+ state,
+ is_system);
+
+ /*
+ * this happens for system-wide context
+ */
+ if (task == NULL)
+ task = current;
+
+ /*
+ * compute elapsed time
+ *
+ * for non-self-monitorint, the thread is necessarily stopped
+ * and total duration has already been computed in ctxsw out.
+ */
+ if (task == current) {
+ ctx->duration += now_itc - ctx->duration_start;
+ /*
+ * don't update set duration if masked
+ */
+ if (state == PFM_CTX_LOADED)
+ set->duration += now_itc - set->duration_start;
+ }
+
+ pfm_arch_stop(task, ctx, set);
+
+ ctx->flags.started = 0;
+
+ return 0;
+}
+
+int __pfm_restart(struct pfm_context *ctx)
+{
+ int state, is_system;
+
+ state = ctx->state;
+ is_system = ctx->flags.system;
+
+ switch(state) {
+ case PFM_CTX_MASKED:
+ break;
+ case PFM_CTX_LOADED:
+ if (ctx->smpl_addr && ctx->smpl_fmt->fmt_restart)
+ break;
+ /* fall through */
+ case PFM_CTX_UNLOADED:
+ case PFM_CTX_ZOMBIE:
+ PFM_DBG("invalid state=%d", state);
+ return -EBUSY;
+ default:
+ PFM_DBG("state=%d with no active_restart handler",
+ state);
+ return -EINVAL;
+ }
+ /*
+ * at this point, the context is either LOADED or MASKED
+ */
+
+ if (ctx->task == current || is_system) {
+ pfm_resume_after_ovfl(ctx);
+ return 0;
+ }
+
+ /*
+ * restart another task
+ */
+
+ /*
+ * When PFM_CTX_MASKED, we cannot issue a restart before the previous
+ * one is seen by the task.
+ */
+ if (state == PFM_CTX_MASKED) {
+ if (ctx->flags.can_restart == 0) {
+ PFM_DBG("cannot restart can_restart=%d",
+ ctx->flags.can_restart);
+ return -EBUSY;
+ }
+ /*
+ * prevent subsequent restart before this one is
+ * seen by the task
+ */
+ ctx->flags.can_restart = 0;
+ }
+
+ /*
+ * if blocking, then post the semaphore is PFM_CTX_MASKED, i.e.
+ * the task is blocked or on its way to block. That's the normal
+ * restart path. If the monitoring is not masked, then the task
+ * can be actively monitoring and we cannot directly intervene.
+ * Therefore we use the trap mechanism to catch the task and
+ * force it to reset the buffer/reset PMDs.
+ *
+ * if non-blocking, then we ensure that the task will go into
+ * pfm_handle_work() before returning to user mode.
+ *
+ * We cannot explicitely reset another task, it MUST always
+ * be done by the task itself. This works for system wide because
+ * the tool that is controlling the session is logically doing
+ * "self-monitoring".
+ */
+ if (ctx->flags.block && state == PFM_CTX_MASKED) {
+ PFM_DBG("unblocking [%d]", ctx->task->pid);
+ complete(&ctx->restart_complete);
+ } else {
+ struct thread_info *info;
+
+ PFM_DBG("[%d] armed exit trap", ctx->task->pid);
+
+ /*
+ * mark work pending
+ */
+ ctx->flags.trap_reason = PFM_TRAP_REASON_RESET;
+
+ info = ctx->task->thread_info;
+ set_bit(TIF_NOTIFY_RESUME, &info->flags);
+
+ /*
+ * XXX: send reschedule if task runs on another CPU
+ */
+ }
+ return 0;
+}
+/*
+ * XXX: interrupts are masked yet monitoring may be active. Hence they
+ * might be a counter overflow during the call. It will be kept pending
+ * and we might return inconsistent unless we check the state of the counter
+ * and compensate for the overflow. Note that we will not loose a sample
+ * when sampling, however, there may be an issue with simple counting and
+ * virtualization.
+ */
+int __pfm_read_pmds(struct pfm_context *ctx, struct pfarg_pmd *req, int count)
+{
+ u64 val = 0, lval, ovfl_mask, hw_val;
+ u64 sw_cnt;
+ u64 *impl_pmds;
+ struct pfm_event_set *set, *active_set;
+ int i, can_access_pmu = 0;
+ int is_system, error_code;
+ u16 cnum, pmd_type, set_id, prev_set_id, max_pmd;
+
+ is_system = ctx->flags.system;
+ ovfl_mask = pfm_pmu_conf->ovfl_mask;
+ impl_pmds = pfm_pmu_conf->impl_pmds;
+ max_pmd = pfm_pmu_conf->max_pmd;
+ active_set = ctx->active_set;
+ set = NULL;
+ prev_set_id = 0;
+
+ if (likely(ctx->state == PFM_CTX_LOADED)) {
+ /*
+ * this can be true when not self-monitoring only in UP
+ */
+ can_access_pmu = __get_cpu_var(pmu_owner) == ctx->task || is_system;
+
+ if (can_access_pmu)
+ pfm_arch_serialize();
+ }
+ error_code = PFM_REG_RETFL_EINVAL;
+
+ /*
+ * on both UP and SMP, we can only read the PMD from the hardware
+ * register when the task is the owner of the local PMU.
+ */
+ for (i = 0; i < count; i++, req++) {
+
+ cnum = req->reg_num;
+ set_id = req->reg_set;
+
+ if (unlikely(cnum >= max_pmd || !pfm_bv_isset(impl_pmds, cnum)))
+ goto error;
+
+ pmd_type = pfm_pmu_conf->pmd_desc[cnum].type;
+
+ /*
+ * locate event set
+ */
+ if (i == 0 || set_id != prev_set_id) {
+ set = pfm_find_set(ctx, set_id, 0);
+ if (set == NULL) {
+ PFM_DBG("event set%u does not exist",
+ set_id);
+ error_code = PFM_REG_RETFL_NOSET;
+ goto error;
+ }
+ }
+ /*
+ * it is not possible to read a PMD which was not requested:
+ * - explicitly written via pfm_write_pmds()
+ * - provided as a reg_smpl_pmds[] to another PMD during
+ * pfm_write_pmds()
+ *
+ * This is motivated by security and for optimizations purposes:
+ * - on context switch restore, we can restore only what we
+ * use (except when regs directly readable at user level,
+ * e.g., IA-64 self-monitoring, I386 RDTSC).
+ * - do not need to maintain PMC -> PMD dependencies
+ */
+ if (unlikely(pfm_bv_isset(set->used_pmds, cnum) == 0)) {
+ PFM_DBG("pmd%u cannot be read, because never "
+ "requested", cnum);
+ goto error;
+ }
+
+ /*
+ * it is possible to read PMD registers which have not
+ * explicitely been written by the application. In this case
+ * the default value is returned.
+ */
+ val = set->view->set_pmds[cnum];
+ lval = set->pmds[cnum].lval;
+
+ /*
+ * extract remaining ovfl to switch
+ */
+ sw_cnt = set->pmds[cnum].ovflsw_thres;
+
+ /*
+ * If the task is not the current one, then we check if the
+ * PMU state is still in the local live register due to lazy
+ * ctxsw. If true, then we read directly from the registers.
+ */
+ if (set == active_set && can_access_pmu) {
+ hw_val = pfm_read_pmd(ctx, cnum);
+ if (pmd_type & PFM_REG_C64)
+ val = (val & ~ovfl_mask) | (hw_val & ovfl_mask);
+ else
+ val = hw_val;
+ }
+
+ PFM_DBG("set%u pmd%u=0x%llx switch_thres=%llu",
+ set->id,
+ cnum,
+ (unsigned long long)val,
+ (unsigned long long)sw_cnt);
+
+ pfm_retflag_set(req->reg_flags, 0);
+ req->reg_value = val;
+ req->reg_last_reset_val = lval;
+ req->reg_ovfl_switch_cnt = sw_cnt;
+
+ prev_set_id = set_id;
+ }
+ return 0;
+
+error:
+ pfm_retflag_set(req->reg_flags, error_code);
+ return -EINVAL;
+}
+int __pfm_write_pmds(struct pfm_context *ctx, struct pfarg_pmd *req, int count,
+ int compat)
+{
+#define PFM_REGFL_PMD_ALL (PFM_REGFL_RANDOM | \
+ PFM_REGFL_OVFL_NOTIFY| \
+ PFM_REG_RETFL_MASK)
+
+ struct pfm_event_set *set, *active_set;
+ u64 value, hw_val, ovfl_mask;
+ u64 *smpl_pmds, *reset_pmds, *impl_pmds;
+ u32 req_flags, flags;
+ u16 cnum, pmd_type, max_pmd, max_pmc;
+ u16 set_id, prev_set_id;
+ int i, can_access_pmu;
+ int is_counting, is_system;
+ int ret, error_code;
+
+ is_system = ctx->flags.system;
+ ovfl_mask = pfm_pmu_conf->ovfl_mask;
+ active_set = ctx->active_set;
+ max_pmd = pfm_pmu_conf->max_pmd;
+ max_pmc = pfm_pmu_conf->max_pmc;
+ impl_pmds = pfm_pmu_conf->impl_pmds;
+ set = NULL;
+
+ prev_set_id = 0;
+ can_access_pmu = 0;
+
+ /*
+ * we cannot access the actual PMD registers when monitoring is masked
+ */
+ if (likely(ctx->state == PFM_CTX_LOADED))
+ can_access_pmu = __get_cpu_var(pmu_owner) == ctx->task
+ || is_system;
+
+ error_code = PFM_REG_RETFL_EINVAL;
+ ret = -EINVAL;
+
+ for (i = 0; i < count; i++, req++) {
+
+ cnum = req->reg_num;
+ value = req->reg_value;
+ set_id = req->reg_set;
+ req_flags = req->reg_flags;
+ smpl_pmds = req->reg_smpl_pmds;
+ reset_pmds = req->reg_reset_pmds;
+ flags = 0;
+
+ if (unlikely(cnum >= max_pmd || !pfm_bv_isset(impl_pmds, cnum))) {
+ PFM_DBG("pmd%u is not implemented or not accessible",
+ cnum);
+ goto error;
+ }
+
+ pmd_type = pfm_pmu_conf->pmd_desc[cnum].type;
+ is_counting = pmd_type & PFM_REG_C64;
+
+ if (likely(compat == 0)) {
+ if (likely(is_counting)) {
+ /*
+ * ensure only valid flags are set
+ */
+ if (req_flags & ~(PFM_REGFL_PMD_ALL)) {
+ PFM_DBG("pmd%u: invalid flags=0x%x",
+ cnum, req_flags);
+ goto error;
+ }
+
+ if (req_flags & PFM_REGFL_OVFL_NOTIFY)
+ flags |= PFM_REGFL_OVFL_NOTIFY;
+ if (req_flags & PFM_REGFL_RANDOM)
+ flags |= PFM_REGFL_RANDOM;
+ /*
+ * verify validity of smpl_pmds
+ */
+ if (unlikely(bitmap_subset(ulp(smpl_pmds),
+ ulp(impl_pmds),
+ max_pmd) == 0)) {
+ PFM_DBG("invalid smpl_pmds=0x%llx "
+ "for pmd%u",
+ (unsigned long long)smpl_pmds[0],
+ cnum);
+ goto error;
+ }
+ /*
+ * verify validity of reset_pmds
+ */
+ if (unlikely(bitmap_subset(ulp(reset_pmds),
+ ulp(impl_pmds),
+ max_pmd) == 0)) {
+ PFM_DBG("invalid reset_pmds=0x%llx "
+ "for pmd%u",
+ (unsigned long long)reset_pmds[0],
+ cnum);
+ goto error;
+ }
+ }
+ }
+
+ /*
+ * locate event set
+ */
+ if (i == 0 || set_id != prev_set_id) {
+ set = pfm_find_set(ctx, set_id, 0);
+ if (set == NULL) {
+ PFM_DBG("event set%u does not exist",
+ set_id);
+ error_code = PFM_REG_RETFL_NOSET;
+ goto error;
+ }
+ }
+
+ pfm_modview_begin(set);
+
+ /*
+ * now commit changes to software state
+ */
+ hw_val = value;
+
+ if (likely(is_counting)) {
+ if (likely(compat == 0)) {
+
+ set->pmds[cnum].flags = flags;
+
+ /*
+ * copy reset and sampling bitvectors
+ */
+ bitmap_copy(ulp(set->pmds[cnum].reset_pmds),
+ ulp(reset_pmds),
+ max_pmd);
+
+ bitmap_copy(ulp(set->pmds[cnum].smpl_pmds),
+ ulp(smpl_pmds),
+ max_pmd);
+
+ set->pmds[cnum].eventid = req->reg_smpl_eventid;
+
+ /*
+ * Mark reset/smpl PMDS as used.
+ *
+ * We do not keep track of PMC because we have to
+ * systematically restore ALL of them.
+ */
+ bitmap_or(ulp(set->used_pmds),
+ ulp(set->used_pmds),
+ ulp(reset_pmds), max_pmd);
+
+ bitmap_or(ulp(set->used_pmds),
+ ulp(set->used_pmds),
+ ulp(smpl_pmds), max_pmd);
+
+ /*
+ * we reprogrammed the PMD hence, clear any pending
+ * ovfl, switch based on the old value
+ * for restart we have already established new values
+ */
+ pfm_bv_clear(set->povfl_pmds, cnum);
+ pfm_bv_clear(set->ovfl_pmds, cnum);
+
+ /*
+ * update ovfl_notify
+ */
+ if (flags & PFM_REGFL_OVFL_NOTIFY)
+ pfm_bv_set(set->ovfl_notify, cnum);
+ else
+ pfm_bv_clear(set->ovfl_notify, cnum);
+ }
+ /*
+ * reset last value to new value
+ */
+ set->pmds[cnum].lval = value;
+
+ hw_val = value & ovfl_mask;
+
+ /*
+ * establish new switch count
+ */
+ set->pmds[cnum].ovflsw_thres = req->reg_ovfl_switch_cnt;
+ set->pmds[cnum].ovflsw_ref_thres = req->reg_ovfl_switch_cnt;
+ }
+
+ /*
+ * update reset values (not just for counters)
+ */
+ set->pmds[cnum].long_reset = req->reg_long_reset;
+ set->pmds[cnum].short_reset = req->reg_short_reset;
+
+ /*
+ * update randomization parameters (not just for counters)
+ */
+ set->pmds[cnum].seed = req->reg_random_seed;
+ set->pmds[cnum].mask = req->reg_random_mask;
+
+ /*
+ * update set values
+ */
+ set->view->set_pmds[cnum] = value;
+
+ pfm_modview_end(set);
+
+ pfm_bv_set(set->used_pmds, cnum);
+
+ if (set == active_set) {
+ set->priv_flags |= PFM_SETFL_PRIV_MOD_PMDS;
+ if (can_access_pmu)
+ pfm_write_pmd(ctx, cnum, hw_val);
+ }
+
+ /*
+ * update number of used PMD registers
+ */
+ set->nused_pmds = bitmap_weight(ulp(set->used_pmds), max_pmd);
+
+ pfm_retflag_set(req->reg_flags, 0);
+
+ prev_set_id = set_id;
+
+ PFM_DBG("set%u pmd%u=0x%llx flags=0x%x a_pmu=%d "
+ "hw_pmd=0x%llx ctx_pmd=0x%llx s_reset=0x%llx "
+ "l_reset=0x%llx u_pmds=0x%llx nu_pmds=%u "
+ "s_pmds=0x%llx r_pmds=0x%llx o_pmds=0x%llx "
+ "o_thres=%llu compat=%d eventid=%llx",
+ set->id,
+ cnum,
+ (unsigned long long)value,
+ set->pmds[cnum].flags,
+ can_access_pmu,
+ (unsigned long long)hw_val,
+ (unsigned long long)set->view->set_pmds[cnum],
+ (unsigned long long)set->pmds[cnum].short_reset,
+ (unsigned long long)set->pmds[cnum].long_reset,
+ (unsigned long long)set->used_pmds[0],
+ set->nused_pmds,
+ (unsigned long long)set->pmds[cnum].smpl_pmds[0],
+ (unsigned long long)set->pmds[cnum].reset_pmds[0],
+ (unsigned long long)set->ovfl_pmds[0],
+ (unsigned long long)set->pmds[cnum].ovflsw_thres,
+ compat,
+ (unsigned long long)set->pmds[cnum].eventid);
+ }
+
+ /*
+ * make changes visible
+ */
+ if (can_access_pmu)
+ pfm_arch_serialize();
+
+ return 0;
+
+error:
+ /*
+ * for now, we have only one possibility for error
+ */
+ pfm_retflag_set(req->reg_flags, error_code);
+ return ret;
+}
+
+int __pfm_write_pmcs(struct pfm_context *ctx, struct pfarg_pmc *req, int count)
+{
+#define PFM_REGFL_PMC_ALL (PFM_REGFL_NO_EMUL64|PFM_REG_RETFL_MASK)
+ struct pfm_event_set *set, *active_set;
+ u64 value, default_value, reserved_mask;
+ u64 *impl_pmcs;
+ int i, can_access_pmu;
+ int is_system, has_wr_check;
+ int ret, error_code;
+ u16 set_id, prev_set_id;
+ u16 cnum, pmc_type, max_pmc;
+ u32 flags;
+ pfm_reg_check_t wr_func;
+
+ is_system = ctx->flags.system;
+ active_set = ctx->active_set;
+
+ wr_func = pfm_pmu_conf->pmc_write_check;
+ max_pmc = pfm_pmu_conf->max_pmc;
+ impl_pmcs = pfm_pmu_conf->impl_pmcs;
+
+ set = NULL;
+ prev_set_id = 0;
+ can_access_pmu = 0;
+
+ /*
+ * we cannot access the actual PMC registers when monitoring is masked
+ */
+ if (likely(ctx->state == PFM_CTX_LOADED))
+ can_access_pmu = __get_cpu_var(pmu_owner) == ctx->task
+ || is_system;
+
+ error_code = PFM_REG_RETFL_EINVAL;
+
+ has_wr_check = wr_func != NULL && (pfm_controls.expert_mode == 0);
+
+ for (i = 0; i < count; i++, req++) {
+
+ ret = -EINVAL;
+ cnum = req->reg_num;
+ set_id = req->reg_set;
+ value = req->reg_value;
+ flags = req->reg_flags;
+
+ /*
+ * no access to unimplemented PMC register
+ */
+ if (unlikely(cnum >= max_pmc || !pfm_bv_isset(impl_pmcs, cnum))) {
+ PFM_DBG("pmc%u is not implemented/unaccessible",
+ cnum);
+ error_code = PFM_REG_RETFL_NOTAVAIL;
+ goto error;
+ }
+
+ pmc_type = pfm_pmu_conf->pmc_desc[cnum].type;
+ default_value = pfm_pmu_conf->pmc_desc[cnum].default_value;
+ reserved_mask = pfm_pmu_conf->pmc_desc[cnum].reserved_mask;
+
+ /*
+ * ensure only valid flags are set
+ */
+ if (flags & ~(PFM_REGFL_PMC_ALL)) {
+ PFM_DBG("pmc%u: invalid flags=0x%x", cnum, flags);
+ goto error;
+ }
+
+ /*
+ * locate event set
+ */
+ if (i == 0 || set_id != prev_set_id) {
+ set = pfm_find_set(ctx, set_id, 0);
+ if (set == NULL) {
+ PFM_DBG("event set%u does not exist",
+ set_id);
+ error_code = PFM_REG_RETFL_NOSET;
+ goto error;
+ }
+ }
+
+ /*
+ * set reserved bits to default values
+ */
+ value = (value & reserved_mask) | (default_value & ~reserved_mask);
+
+ if (flags & PFM_REGFL_NO_EMUL64) {
+ if ((pmc_type & PFM_REG_NO64) == 0) {
+ PFM_DBG("pmc%u no support "
+ "PFM_REGFL_NO_EMUL64", cnum);
+ goto error;
+ }
+ value &= ~pfm_pmu_conf->pmc_desc[cnum].no_emul64_mask;
+ }
+
+ /*
+ * execute write checker, if any
+ */
+ if (likely(has_wr_check && (pmc_type & PFM_REG_WC))) {
+ u64 v = value;
+ ret = (*wr_func)(ctx, set, cnum, flags, &v);
+ if (ret)
+ goto error;
+ value = v ;
+ }
+
+ /*
+ * Now we commit the changes
+ */
+
+ /*
+ * mark PMC register as used
+ * We do not track associated PMC register based on
+ * the fact that they will likely need to be written
+ * in order to become useful at which point the statement
+ * below will catch that.
+ *
+ * The used_pmcs bitmask is only useful on architectures where
+ * the PMC need to be modified for particular bits, especially
+ * on overflow or to stop/start.
+ */
+ if (pfm_bv_isset(set->used_pmcs, cnum) == 0) {
+ pfm_bv_set(set->used_pmcs, cnum);
+ set->nused_pmcs++;
+ }
+
+ set->pmcs[cnum] = value;
+
+ if (set == active_set) {
+ set->priv_flags |= PFM_SETFL_PRIV_MOD_PMCS;
+ if (can_access_pmu)
+ pfm_arch_write_pmc(ctx, cnum, value);
+ }
+
+ pfm_retflag_set(req->reg_flags, 0);
+
+ prev_set_id = set_id;
+
+ PFM_DBG("set%u pmc%u=0x%llx a_pmu=%d "
+ "u_pmcs=0x%llx nu_pmcs=%u",
+ set->id,
+ cnum,
+ (unsigned long long)value,
+ can_access_pmu,
+ (unsigned long long)set->used_pmcs[0],
+ set->nused_pmcs);
+ }
+ /*
+ * make sure the changes are visible
+ *
+ * XXX: should check the we actually touched HW
+ */
+ if (can_access_pmu)
+ pfm_arch_serialize();
+
+ return 0;
+error:
+ pfm_retflag_set(req->reg_flags, error_code);
+ return ret;
+}
+/*
+ * should not call when task == current
+ */
+static int pfm_bad_permissions(struct task_struct *task)
+{
+ /* inspired by ptrace_attach() */
+ PFM_DBG("cur: euid=%d uid=%d gid=%d task: euid=%d "
+ "suid=%d uid=%d egid=%d cap:%d sgid=%d",
+ current->euid,
+ current->uid,
+ current->gid,
+ task->euid,
+ task->suid,
+ task->uid,
+ task->egid,
+ task->sgid, capable(CAP_SYS_PTRACE));
+
+ return ((current->uid != task->euid)
+ || (current->uid != task->suid)
+ || (current->uid != task->uid)
+ || (current->gid != task->egid)
+ || (current->gid != task->sgid)
+ || (current->gid != task->gid)) && !capable(CAP_SYS_PTRACE);
+}
+
+
+/*
+ * cannot attach if :
+ * - kernel task
+ * - task not owned by caller
+ * - task incompatible with context mode
+ */
+static int pfm_task_incompatible(struct pfm_context *ctx,
+ struct task_struct *task)
+{
+ /*
+ * no kernel task or task not owned by caller
+ */
+ if (task->mm == NULL) {
+ PFM_DBG("cannot attach to kernel thread [%d]", task->pid);
+ return -EPERM;
+ }
+
+ if (pfm_bad_permissions(task)) {
+ PFM_DBG("no permission to attach to [%d]", task->pid);
+ return -EPERM;
+ }
+
+ /*
+ * cannot block in self-monitoring mode
+ */
+ if (ctx->flags.block && task == current) {
+ PFM_DBG("cannot load a in blocking mode on self for [%d]",
+ task->pid);
+ return -EINVAL;
+ }
+
+ if (task->state == EXIT_ZOMBIE || task->state == EXIT_DEAD) {
+ PFM_DBG("cannot attach to zombie/dead task [%d]", task->pid);
+ return -EBUSY;
+ }
+
+ /*
+ * always ok for self
+ */
+ if (task == current)
+ return 0;
+
+ if ((task->state != TASK_STOPPED) && (task->state != TASK_TRACED)) {
+ PFM_DBG("cannot attach to non-stopped task [%d] state=%ld",
+ task->pid, task->state);
+ return -EBUSY;
+ }
+ PFM_DBG("before wait_inactive() task [%d] state=%ld",
+ task->pid, task->state);
+ /*
+ * make sure the task is off any CPU
+ */
+ wait_task_inactive(task);
+
+ PFM_DBG("after wait_inactive() task [%d] state=%ld",
+ task->pid, task->state);
+ /* more to come... */
+
+ return 0;
+}
+static int pfm_get_task(struct pfm_context *ctx, pid_t pid,
+ struct task_struct **task)
+{
+ struct task_struct *p = current;
+ int ret;
+
+ /* XXX: need to add more checks here */
+ if (pid < 2)
+ return -EPERM;
+
+ if (pid != current->pid) {
+
+ read_lock(&tasklist_lock);
+
+ p = find_task_by_pid(pid);
+
+ /* make sure task cannot go away while we operate on it */
+ if (p)
+ get_task_struct(p);
+
+ read_unlock(&tasklist_lock);
+
+ if (p == NULL)
+ return -ESRCH;
+ }
+
+ ret = pfm_task_incompatible(ctx, p);
+ if (ret == 0) {
+ *task = p;
+ } else if (p != current) {
+ put_task_struct(p);
+ }
+ return ret;
+}
+
+static int pfm_check_task_exist(struct pfm_context *ctx)
+{
+ struct task_struct *g, *t;
+ int ret = -ESRCH;
+
+ read_lock(&tasklist_lock);
+
+ do_each_thread (g, t) {
+ if (t->pfm_context == ctx) {
+ ret = 0;
+ break;
+ }
+ } while_each_thread (g, t);
+
+ read_unlock(&tasklist_lock);
+
+ PFM_DBG("ret=%d ctx=%p", ret, ctx);
+
+ return ret;
+}
+
+
+static int pfm_load_context_thread(struct pfm_context *ctx, pid_t pid,
+ struct pfm_event_set *set)
+{
+ struct task_struct *task = NULL;
+ struct pfm_context *old;
+ u32 set_flags;
+ unsigned long info;
+ int ret, state;
+
+ state = ctx->state;
+ set_flags = set->flags;
+
+ PFM_DBG("load_pid [%d] set=%u runs=%llu set_flags=0x%x",
+ pid,
+ set->id,
+ (unsigned long long)set->view->set_runs,
+ set_flags);
+
+ if (ctx->flags.block && pid == current->pid) {
+ PFM_DBG("cannot use blocking mode in while self-monitoring");
+ return -EINVAL;
+ }
+
+ ret = pfm_get_task(ctx, pid, &task);
+ if (ret) {
+ PFM_DBG("load_pid [%d] get_task=%d", pid, ret);
+ return ret;
+ }
+
+ ret = pfm_arch_load_context(ctx, task);
+ if (ret) {
+ put_task_struct(task);
+ return ret;
+ }
+
+ /*
+ * now reserve the session
+ */
+ ret = pfm_reserve_session(ctx, -1);
+ if (ret)
+ goto error;
+
+ /*
+ * task is necessarily stopped at this point.
+ *
+ * If the previous context was zombie, then it got removed in
+ * pfm_ctxswout_thread(). Therefore we should not see it here.
+ * If we see a context, then this is an active context
+ *
+ */
+ PFM_DBG("before cmpxchg() old_ctx=%p new_ctx=%p",
+ task->pfm_context, ctx);
+
+ ret = -EEXIST;
+
+ old = cmpxchg(&task->pfm_context, NULL, ctx);
+ if (old != NULL) {
+ PFM_DBG("load_pid [%d] has already a context "
+ "old=%p new=%p cur=%p",
+ pid,
+ old,
+ ctx,
+ task->pfm_context);
+ goto error_unres;
+ }
+
+ if (set_flags & PFM_SETFL_OVFL_SWITCH) {
+ pfm_reload_switch_thresholds(set);
+ } else if (set_flags & PFM_SETFL_TIME_SWITCH) {
+ set->timeout = set->switch_timeout;
+ }
+
+ /*
+ * link context to task
+ */
+ ctx->task = task;
+
+ /*
+ * commit active set
+ */
+ ctx->active_set = set;
+
+ pfm_modview_begin(set);
+
+ set->view->set_runs++;
+
+ set->view->set_status |= PFM_SETVFL_ACTIVE;
+
+ /*
+ * self-monitoring
+ */
+ if (task == current) {
+#ifndef CONFIG_SMP
+ struct pfm_context *ctxp;
+
+ /*
+ * in UP per-thread, due to lazy save
+ * there could be a context from another
+ * task. We need to push it first before
+ * installing our new state
+ */
+ ctxp = __get_cpu_var(pmu_ctx);
+ if (ctxp)
+ pfm_save_pmds_release(ctxp);
+#endif
+ pfm_set_last_cpu(ctx, smp_processor_id());
+ pfm_inc_activation();
+ pfm_set_activation(ctx);
+
+ /*
+ * setting PFM_CPUINFO_TIME_SWITCH, triggers
+ * further checking if __pfm_handle_switch_timeout().
+ * switch timeout is effectively decremented only once
+ * monitoring has been activated via pfm_start() or
+ * any user level equivalent.
+ */
+ if (set_flags & PFM_SETFL_TIME_SWITCH) {
+ info = PFM_CPUINFO_TIME_SWITCH;
+ __get_cpu_var(pfm_syst_info) = info;
+ }
+ /*
+ * load all PMD from set
+ * load all PMC from set
+ */
+ pfm_arch_restore_pmds(ctx, set);
+ pfm_arch_restore_pmcs(ctx, set);
+
+ /*
+ * set new ownership
+ */
+ pfm_set_pmu_owner(task, ctx);
+
+ PFM_DBG("context loaded on PMU for [%d]", task->pid);
+ } else {
+
+ /* force a full reload */
+ ctx->last_act = PFM_INVALID_ACTIVATION;
+ pfm_set_last_cpu(ctx, -1);
+ set->priv_flags |= PFM_SETFL_PRIV_MOD_BOTH;
+ }
+
+ pfm_modview_end(set);
+
+ ret = 0;
+
+error_unres:
+ if (ret)
+ pfm_release_session(ctx, -1);
+error:
+ /*
+ * release task, there is now a link with the context
+ */
+ if (task != current) {
+ put_task_struct(task);
+
+ if (ret == 0) {
+ ret = pfm_check_task_exist(ctx);
+ if (ret) {
+ ctx->state = PFM_CTX_UNLOADED;
+ ctx->task = NULL;
+ }
+ }
+ }
+ return ret;
+}
+
+static int pfm_load_context_sys(struct pfm_context *ctx, struct pfm_event_set *set)
+{
+ u32 set_flags;
+ unsigned long info;
+ u32 my_cpu;
+ int ret;
+
+ my_cpu = smp_processor_id();
+
+ set_flags = set->flags;
+
+ ret = pfm_arch_load_context(ctx, NULL);
+ if (ret)
+ return ret;
+
+ PFM_DBG("cpu=%d set=%u runs=%llu set_flags=0x%x",
+ smp_processor_id(),
+ set->id,
+ (unsigned long long)set->view->set_runs,
+ set_flags);
+
+ /*
+ * now reserve the session
+ */
+ ret = pfm_reserve_session(ctx, my_cpu);
+ if (ret)
+ return ret;
+
+ /*
+ * bind context to current CPU
+ */
+ ctx->cpu = my_cpu;
+ ctx->task = NULL;
+
+ /*
+ * setting PFM_CPUINFO_TIME_SWITCH, triggers
+ * further checking if __pfm_handle_switch_timeout().
+ * switch timeout is effectively decremented only when
+ * monitoring has been activated via pfm_start() or
+ * any user level equivalent.
+ */
+ if (set_flags & PFM_SETFL_OVFL_SWITCH) {
+ pfm_reload_switch_thresholds(set);
+ } else if (set_flags & PFM_SETFL_TIME_SWITCH) {
+ set->timeout = set->switch_timeout;
+ info = PFM_CPUINFO_TIME_SWITCH;
+ __get_cpu_var(pfm_syst_info) = info;
+ }
+
+ pfm_modview_begin(set);
+
+ set->view->set_runs++;
+
+ /*
+ * commit active set
+ */
+ ctx->active_set = set;
+ set->view->set_status |= PFM_SETVFL_ACTIVE;
+
+ /*
+ * load all registes from ctx to PMU
+ */
+ pfm_arch_restore_pmds(ctx, set);
+ pfm_arch_restore_pmcs(ctx, set);
+
+ pfm_modview_end(set);
+
+ set->priv_flags &= ~PFM_SETFL_PRIV_MOD_BOTH;
+
+ PFM_DBG("context loaded on CPU%d", my_cpu);
+
+ pfm_set_pmu_owner(NULL, ctx);
+
+ return 0;
+}
+
+int __pfm_load_context(struct pfm_context *ctx, struct pfarg_load *req)
+{
+ struct pfm_event_set *set;
+ int ret = 0;
+
+ /*
+ * can only load from unloaded
+ */
+ if (ctx->state != PFM_CTX_UNLOADED) {
+ PFM_DBG("context already loaded");
+ return -EBUSY;
+ }
+
+ set = pfm_find_set(ctx, req->load_set, 0);
+ if (set == NULL) {
+ PFM_DBG("event set%u does not exist", req->load_set);
+ return -EINVAL;
+ }
+ /*
+ * assess sanity of the event sets
+ */
+ ret = pfm_prepare_sets(ctx);
+ if (ret) {
+ PFM_DBG("invalid next field pointers in the sets");
+ return -EINVAL;
+ }
+
+ if (ctx->flags.system)
+ ret = pfm_load_context_sys(ctx, set);
+ else
+ ret = pfm_load_context_thread(ctx, req->load_pid, set);
+
+ if (ret)
+ return ret;
+
+ /*
+ * reset message queue
+ */
+ pfm_reset_msgq(ctx);
+
+ ctx->duration = 0;
+ ctx->flags.started = 0;
+ ctx->flags.trap_reason = PFM_TRAP_REASON_NONE;
+ ctx->flags.can_restart = 0;
+ ctx->state = PFM_CTX_LOADED;
+
+ return 0;
+}
+
+int __pfm_unload_context(struct pfm_context *ctx, int defer_release)
+{
+ struct task_struct *task;
+ struct pfm_event_set *set;
+ int state, ret, is_self;
+
+ state = ctx->state;
+
+ /*
+ * unload only when necessary
+ */
+ if (state == PFM_CTX_UNLOADED) {
+ PFM_DBG("nothing to do");
+ return 0;
+ }
+ task = ctx->task;
+ set = ctx->active_set;
+ is_self = ctx->flags.system || task == current;
+
+ PFM_DBG("ctx_state=%d task [%d]", state, task ? task->pid : -1);
+
+ /*
+ * stop monitoring
+ */
+ ret = __pfm_stop(ctx);
+ if (ret)
+ return ret;
+
+ pfm_modview_begin(set);
+ set->view->set_status &= ~PFM_SETVFL_ACTIVE;
+ pfm_modview_end(set);
+
+ ctx->state = PFM_CTX_UNLOADED;
+
+ /*
+ * clear any leftover in pfm_syst_info.
+ *
+ * for non-self monitoring,
+ * this is done in pfm_ctxswout_thread.
+ */
+ if (is_self)
+ __get_cpu_var(pfm_syst_info) = 0;
+
+ /*
+ * save PMDs to context
+ * release ownership
+ */
+ pfm_flush_pmds(task, ctx);
+
+ pfm_arch_unload_context(ctx, task);
+
+ /*
+ * at this point we are done with the PMU
+ * so we can release the resource.
+ *
+ * when state was ZOMBIE, we have already released
+ */
+ if (state != PFM_CTX_ZOMBIE && defer_release == 0)
+ pfm_release_session(ctx, ctx->cpu);
+
+ /*
+ * reset activation counter
+ */
+ ctx->last_act = PFM_INVALID_ACTIVATION;
+ pfm_set_last_cpu(ctx, -1);
+
+ /*
+ * break links between context and task
+ */
+ if (task) {
+ task->pfm_context = NULL;
+ ctx->task = NULL;
+ }
+ PFM_DBG("done, state was %d", state);
+ return 0;
+}
+
+/*
+ * context is unloaded for this command. Interrupts are enabled
+ */
+int __pfm_delete_evtsets(struct pfm_context *ctx, void *arg, int count)
+{
+ struct pfarg_setdesc *req = arg;
+ struct pfm_event_set *set, *prev;
+ kmem_cache_t *cachep;
+ u16 set_id;
+ size_t view_size;
+ int i;
+
+ /* delete operation only works when context is detached */
+ BUG_ON(ctx->state != PFM_CTX_UNLOADED);
+
+ view_size = PAGE_ALIGN(sizeof(struct pfm_set_view));
+
+ PFM_DBG("active_set=%u", ctx->active_set->id);
+
+ if (ctx->flags.mapset)
+ cachep = pfm_set_cachep;
+ else
+ cachep = pfm_lg_set_cachep;
+
+ for (i = 0; i < count; i++, req++) {
+ set_id = req->set_id;
+ /*
+ * cannot remove set 0
+ */
+ if (set_id == 0)
+ goto error;
+
+ prev = NULL;
+ for (set = ctx->sets; set; set = set->next) {
+ if (set->id == set_id) break;
+ prev = set;
+ }
+
+ if (set == NULL) {
+ PFM_DBG("set_id=%u not found", set_id);
+ goto error;
+ }
+
+ if (prev)
+ prev->next = set->next;
+ else
+ ctx->sets = set->next;
+
+ /*
+ * correct default active set if necessary
+ */
+ if (set == ctx->active_set) {
+ ctx->active_set = set->next ?
+ set->next : ctx->sets;
+ }
+
+ vfree(set->view);
+ kmem_cache_free(cachep, set);
+
+ pfm_retflag_set(req->set_flags, 0);
+
+ PFM_DBG("deleted set_id=%u", set_id);
+ }
+ return 0;
+error:
+ pfm_retflag_set(req->set_flags, PFM_REG_RETFL_EINVAL);
+ return -EINVAL;
+}
+
+static int pfm_setfl_sane(struct pfm_context *ctx, u32 flags)
+{
+#define PFM_SETFL_BOTH_SWITCH (PFM_SETFL_OVFL_SWITCH|PFM_SETFL_TIME_SWITCH)
+ int ret;
+
+ ret = pfm_arch_setfl_sane(ctx, flags);
+ if (ret)
+ return ret;
+
+ if ((flags & PFM_SETFL_BOTH_SWITCH) == PFM_SETFL_BOTH_SWITCH) {
+ PFM_DBG("both switch ovfl and switch time are set");
+ return -EINVAL;
+ }
+
+ if ((flags & PFM_SETFL_EXCL_IDLE) != 0 && ctx->flags.system == 0) {
+ PFM_DBG("excl idle is for system wide only");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/*
+ * it is never possible to change the identification of an existing set
+ */
+static int __pfm_change_event_set(struct pfm_context *ctx,
+ struct pfm_event_set *set,
+ struct pfarg_setdesc *req)
+{
+ u32 flags;
+ u16 set_id, set_id_next, max_pmd;
+ unsigned long ji;
+ int ret;
+
+ BUG_ON(ctx->state == PFM_CTX_LOADED);
+
+ set_id = req->set_id;
+ set_id_next = req->set_id_next;
+ flags = req->set_flags;
+ max_pmd = pfm_pmu_conf->max_pmd;
+
+ ret = pfm_setfl_sane(ctx, flags);
+ if (ret) {
+ PFM_DBG("invalid flags 0x%x set %u", flags, set_id);
+ return -EINVAL;
+ }
+
+ /*
+ * commit changes
+ *
+ * note that we defer checking the validity of set_id_next until the
+ * context is actually attached. This is the only moment where we can
+ * safely assess the sanity of the sets because sets cannot be changed
+ * or deleted once the context is attached
+ */
+ set->id = set_id;
+ set->id_next = set_id_next;
+ set->flags = flags;
+ set->priv_flags = 0;
+
+ /*
+ * XXX: what about set_priv_flags
+ */
+
+ /*
+ * reset pointer to next set
+ */
+ set->switch_next = NULL;
+
+ ji = usecs_to_jiffies(req->set_timeout);
+
+ /*
+ * verify that timeout is not 0
+ */
+ if (ji == 0 && (flags & PFM_SETFL_TIME_SWITCH) != 0) {
+ PFM_DBG("invalid timeout=0");
+ return -EINVAL;
+ }
+
+ set->switch_timeout = set->timeout = ji;
+
+ /*
+ * return actual timeout in usecs
+ */
+ req->set_timeout = jiffies_to_usecs(ji);
+
+ PFM_DBG("set %u flags=0x%x id_next=%u req_usec=%u"
+ "jiffies=%lu runs=%llu HZ=%u TICK_NSEC=%lu eff_usec=%u",
+ set_id,
+ flags,
+ set_id_next,
+ req->set_timeout,
+ ji,
+ (unsigned long long)set->view->set_runs,
+ HZ, TICK_NSEC,
+ req->set_timeout);
+
+ return 0;
+}
+
+/*
+ * context is unloaded for this command. Interrupts are enabled
+ */
+int __pfm_create_evtsets(struct pfm_context *ctx, struct pfarg_setdesc *req,
+ int count)
+{
+ struct pfm_event_set *set;
+ u16 set_id;
+ int i, ret;
+
+ for (i = 0; i < count; i++, req++) {
+ set_id = req->set_id;
+
+ PFM_DBG("set_id=%u", set_id);
+
+ set = pfm_find_set(ctx, set_id, 1);
+ if (set == NULL)
+ goto error_mem;
+
+ ret = __pfm_change_event_set(ctx, set, req);
+ if (ret)
+ goto error_params;
+
+ pfm_init_evtset(set);
+ }
+ return 0;
+error_mem:
+ PFM_DBG("cannot allocate set %u", set_id);
+ pfm_retflag_set(req->set_flags, PFM_REG_RETFL_EINVAL);
+ return -ENOMEM;
+error_params:
+ pfm_retflag_set(req->set_flags, PFM_REG_RETFL_EINVAL);
+ return ret;
+}
+
+int __pfm_getinfo_evtsets(struct pfm_context *ctx, struct pfarg_setinfo *req,
+ int count)
+{
+ struct pfm_event_set *set;
+ int i, is_system, is_loaded;
+ u16 set_id;
+ int max_cnt_pmd;
+ u64 end_cycles;
+
+ PFM_DBG("active_set=%u", ctx->active_set->id);
+
+ end_cycles = pfm_arch_get_itc();
+ is_system = ctx->flags.system;
+ is_loaded = ctx->state == PFM_CTX_LOADED;
+ max_cnt_pmd = pfm_pmu_conf->max_cnt_pmd;
+
+ for (i = 0; i < count; i++, req++) {
+
+ set_id = req->set_id;
+
+ PFM_DBG("set_id=%u", set_id);
+
+ for (set = ctx->sets; set; set = set->next) {
+ if (set->id == set_id)
+ goto found;
+ }
+ PFM_DBG("set %u not found", set_id);
+ pfm_retflag_set(req->set_flags, PFM_REG_RETFL_EINVAL);
+ return -EINVAL;
+found:
+ /*
+ * compute leftover timeout
+ */
+
+ req->set_flags = set->flags;
+ req->set_timeout = jiffies_to_usecs(set->timeout);
+ req->set_runs = set->view->set_runs;
+ req->set_act_duration = set->duration;
+ req->set_mmap_offset = set->mmap_offset;
+
+ /*
+ * adjust for active set if needed
+ */
+ if (is_system && is_loaded && ctx->flags.started
+ && set == ctx->active_set)
+ req->set_act_duration += end_cycles
+ - set->duration_start;
+
+ /*
+ * copy the list of pmds which last overflowed for
+ * the set
+ */
+ bitmap_copy(ulp(req->set_ovfl_pmds),
+ ulp(set->ovfl_pmds),
+ max_cnt_pmd);
+
+ pfm_retflag_set(req->set_flags, 0);
+
+ PFM_DBG("set %u flags=0x%x eff_usec=%u runs=%llu",
+ set_id,
+ set->flags,
+ req->set_timeout,
+ (unsigned long long)set->view->set_runs);
+ }
+ return 0;
+}
+
+
+
+static int pfm_ctx_flags_sane(u32 ctx_flags)
+{
+ /* valid signal */
+
+ if (ctx_flags & PFM_FL_SYSTEM_WIDE) {
+ /*
+ * cannot block in this mode
+ */
+ if (ctx_flags & PFM_FL_NOTIFY_BLOCK) {
+ PFM_DBG("cannot use blocking mode in syswide mode");
+ return -EINVAL;
+ }
+ }
+ /* probably more to add here */
+ return 0;
+}
+
+/*
+ * check for permissions to create a context
+ */
+static inline int pfm_ctx_permissions(u32 ctx_flags)
+{
+ if ( (ctx_flags & PFM_FL_SYSTEM_WIDE)
+ && pfm_controls.sys_group != PFM_GROUP_PERM_ANY
+ && in_group_p(pfm_controls.sys_group)) {
+ PFM_DBG("user group not allowed to create a syswide ctx");
+ return -EPERM;
+ } else if (pfm_controls.task_group != PFM_GROUP_PERM_ANY
+ && in_group_p(pfm_controls.task_group)) {
+ PFM_DBG("user group not allowed to create a task context");
+ return -EPERM;
+ }
+ return 0;
+}
+
+int __pfm_create_context(struct pfarg_ctx *req, struct pfm_smpl_fmt *fmt,
+ void *fmt_arg, int compat_mode,
+ struct pfm_context **new_ctx)
+{
+ struct pfm_context *ctx;
+ struct file *filp = NULL;
+ u32 ctx_flags;
+ int fd = 0, ret;
+
+ ctx_flags = req->ctx_flags;
+
+ /* Increase refcount on PMU description */
+ ret = pfm_pmu_conf_get(compat_mode != PFM_KAPI);
+ if (ret < 0)
+ goto error_conf;
+
+ ret = pfm_ctx_flags_sane(ctx_flags);
+ if (ret < 0)
+ goto error_alloc;
+
+ ret = pfm_ctx_permissions(ctx_flags);
+ if (ret < 0)
+ goto error_alloc;
+
+ ret = -ENOMEM;
+ ctx = pfm_context_alloc();
+ if (!ctx)
+ goto error_alloc;
+
+ /*
+ * link to format, must be done first for correct
+ * error handling in pfm_context_free()
+ */
+ ctx->smpl_fmt = fmt;
+
+ if (compat_mode != PFM_KAPI) {
+ ret = -ENFILE;
+ fd = pfm_alloc_fd(&filp);
+ if (fd < 0)
+ goto error_file;
+ }
+
+ /*
+ * context is unloaded
+ */
+ ctx->state = PFM_CTX_UNLOADED;
+
+ /*
+ * initialization of context's flags
+ * must be done before pfm_find_set()
+ */
+ ctx->flags.block = (ctx_flags & PFM_FL_NOTIFY_BLOCK) ? 1 : 0;
+ ctx->flags.system = (ctx_flags & PFM_FL_SYSTEM_WIDE) ? 1: 0;
+ ctx->flags.no_msg = (ctx_flags & PFM_FL_OVFL_NO_MSG) ? 1: 0;
+ ctx->flags.mapset = (ctx_flags & PFM_FL_MAP_SETS) ? 1: 0;
+ ctx->flags.trap_reason = PFM_TRAP_REASON_NONE;
+
+ /*
+ * initialize arch-specific section
+ * must be done before fmt_init()
+ * XXX: fix dependency with fmt_init()
+ */
+ pfm_arch_context_initialize(ctx, ctx_flags);
+
+ ret = -ENOMEM;
+ /*
+ * create initial set
+ */
+ if (pfm_find_set(ctx, 0, 1) == NULL)
+ goto error_set;
+
+ /*
+ * does the user want to sample?
+ */
+ if (fmt) {
+ ret = pfm_setup_smpl_fmt(fmt, fmt_arg, ctx, ctx_flags,
+ compat_mode, filp);
+ if (ret)
+ goto error_set;
+ }
+
+ req->ctx_smpl_buf_size = ctx->smpl_size;
+
+ /*
+ * attach context to file
+ */
+ if (filp)
+ filp->private_data = ctx;
+
+ spin_lock_init(&ctx->lock);
+ init_completion(&ctx->restart_complete);
+
+ /*
+ * activation is used in SMP only
+ */
+ ctx->last_act = PFM_INVALID_ACTIVATION;
+ pfm_set_last_cpu(ctx, -1);
+
+ /*
+ * initialize notification message queue
+ */
+ ctx->msgq_head = ctx->msgq_tail = 0;
+ init_waitqueue_head(&ctx->msgq_wait);
+
+ PFM_DBG("ctx=%p flags=0x%x system=%d notify_block=%d no_msg=%d"
+ " use_fmt=%d remap=%d ctx_fd=%d compat=%d",
+ ctx,
+ ctx_flags,
+ ctx->flags.system,
+ ctx->flags.block,
+ ctx->flags.no_msg,
+ fmt != NULL,
+ ctx->flags.mapset,
+ fd, compat_mode);
+
+ *new_ctx = ctx;
+
+ /*
+ * we defer the fd_install until we are certain the call succeeded
+ * to ensure we do not have to undo its effect. Neither put_filp()
+ * nor put_unused_fd() undoes the effect of fd_install().
+ */
+ if (compat_mode != PFM_KAPI)
+ fd_install(fd, filp);
+
+ req->ctx_fd = fd;
+
+ return 0;
+
+error_set:
+ if (compat_mode != PFM_KAPI) {
+ put_filp(filp);
+ put_unused_fd(fd);
+ }
+error_file:
+ pfm_context_free(ctx);
+ return ret;
+
+error_alloc:
+ pfm_pmu_conf_put();
+error_conf:
+ pfm_smpl_fmt_put(fmt);
+ return ret;
+}
+
+/*
+ * function invoked in case, pfm_context_create fails
+ * at the last operation, copy_to_user. It needs to
+ * undo memory allocations and free the file descriptor
+ */
+void pfm_undo_create_context(int fd, struct pfm_context *ctx)
+{
+ struct files_struct *files = current->files;
+ struct file *file;
+
+ file = fget(fd);
+ /*
+ * there is no fd_uninstall(), so we do it
+ * here. put_unused_fd() does not remove the
+ * effect of fd_install().
+ */
+
+ spin_lock(&files->file_lock);
+ files->fd_array[fd] = NULL;
+ spin_unlock(&files->file_lock);
+
+ /*
+ * undo the fget()
+ */
+ fput(file);
+
+ /*
+ * decrement ref count and kill file
+ */
+ put_filp(file);
+
+ put_unused_fd(fd);
+
+ pfm_context_free(ctx);
+}
--- linux-2.6.17-rc4.orig/perfmon/perfmon_ctxsw.c 1969-12-31 16:00:00.000000000 -0800
+++ linux-2.6.17-rc4/perfmon/perfmon_ctxsw.c 2006-05-12 03:18:52.000000000 -0700
@@ -0,0 +1,405 @@
+/*
+ * perfmon_cxtsw.c: perfmon2 context switch code
+ *
+ * This file implements the perfmon2 interface which
+ * provides access to the hardware performance counters
+ * of the host processor.
+ *
+ * The initial version of perfmon.c was written by
+ * Ganesh Venkitachalam, IBM Corp.
+ *
+ * Then it was modified for perfmon-1.x by Stephane Eranian and
+ * David Mosberger, Hewlett Packard Co.
+ *
+ * Version Perfmon-2.x is a complete rewrite of perfmon-1.x
+ * by Stephane Eranian, Hewlett Packard Co.
+ *
+ * Copyright (c) 1999-2006 Hewlett-Packard Development Company, L.P.
+ * Contributed by Stephane Eranian <[email protected]>
+ * David Mosberger-Tang <[email protected]>
+ *
+ * More information about perfmon available at:
+ * http://www.hpl.hp.com/research/linux/perfmon
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/vmalloc.h>
+#include <linux/sysctl.h>
+#include <linux/file.h>
+#include <linux/poll.h>
+#include <linux/vfs.h>
+#include <linux/pagemap.h>
+#include <linux/mount.h>
+#include <linux/perfmon.h>
+
+
+
+#ifdef CONFIG_SMP
+/*
+ * interrupts are masked, runqueue lock is held, context is locked
+ */
+void pfm_ctxswin_thread(struct task_struct *task, struct pfm_context *ctx,
+ struct pfm_event_set *set, int must_reload)
+{
+ struct thread_struct *t;
+ u64 cur_act;
+ u32 set_flags;
+ int reload_pmcs, reload_pmds;
+
+ BUG_ON(task->pid == 0);
+ BUG_ON(__get_cpu_var(pmu_owner));
+
+ BUG_ON(task->pfm_context != ctx);
+
+ t = &task->thread;
+
+ cur_act = __get_cpu_var(pmu_activation_number);
+
+ set = ctx->active_set;
+ set_flags = set->flags;
+
+ /*
+ * in case fo zombie, we do not complete ctswin of the
+ * PMU, and we force a call to pfm_handle_work() to finish
+ * cleanup, i.e., free context + smpl_buff. The reason for
+ * deferring to pfm_handle_work() is that it is not possible
+ * to vfree() with interrupts disabled.
+ */
+ if (unlikely(ctx->state == PFM_CTX_ZOMBIE)) {
+ struct thread_info *th_info;
+
+ /*
+ * ensure everything is properly stopped
+ */
+ __pfm_stop(ctx);
+
+ ctx->flags.trap_reason = PFM_TRAP_REASON_ZOMBIE;
+ th_info = task->thread_info;
+ set_bit(TIF_NOTIFY_RESUME, &th_info->flags);
+
+ return;
+ }
+
+ if (set_flags & PFM_SETFL_TIME_SWITCH)
+ __get_cpu_var(pfm_syst_info) = PFM_CPUINFO_TIME_SWITCH;
+
+ /*
+ * if we were the last user of the PMU on that CPU,
+ * then nothing to do except restore psr
+ */
+ if (ctx->last_cpu == smp_processor_id() && ctx->last_act == cur_act) {
+ /*
+ * check for forced reload conditions
+ */
+ reload_pmcs = set->priv_flags & PFM_SETFL_PRIV_MOD_PMCS;
+ reload_pmds = set->priv_flags & PFM_SETFL_PRIV_MOD_PMDS;
+ } else {
+ reload_pmcs = 1;
+ reload_pmds = 1;
+ }
+ /* consumed */
+ set->priv_flags &= ~PFM_SETFL_PRIV_MOD_BOTH;
+
+ if (reload_pmds)
+ pfm_arch_restore_pmds(ctx, set);
+
+ /*
+ * need to check if had in-flight interrupt in
+ * pfm_ctxswout_thread(). If at least one bit set, then we must replay
+ * the interrupt to avoid loosing some important performance data.
+ */
+ if (set->npend_ovfls) {
+ pfm_arch_resend_irq();
+ __get_cpu_var(pfm_stats).pfm_ovfl_intr_replay_count++;
+ }
+
+ if (reload_pmcs)
+ pfm_arch_restore_pmcs(ctx, set);
+
+ /*
+ * record current activation for this context
+ */
+ pfm_inc_activation();
+ pfm_set_last_cpu(ctx, smp_processor_id());
+ pfm_set_activation(ctx);
+
+ /*
+ * establish new ownership.
+ */
+ pfm_set_pmu_owner(task, ctx);
+
+ pfm_arch_ctxswin(task, ctx, set);
+}
+#else /* !CONFIG_SMP */
+/*
+ * interrupts are disabled
+ */
+void pfm_ctxswin_thread(struct task_struct *task, struct pfm_context *ctx,
+ struct pfm_event_set *set, int force_reload)
+{
+ u32 set_flags, set_priv_flags;
+
+ set_flags = set->flags;
+ set_priv_flags = set->priv_flags;
+
+ if (set_flags & PFM_SETFL_TIME_SWITCH) {
+ __get_cpu_var(pfm_syst_info) = PFM_CPUINFO_TIME_SWITCH;
+ }
+
+ /*
+ * must force reload due to lazy save
+ */
+ if (force_reload)
+ set_priv_flags |= PFM_SETFL_PRIV_MOD_BOTH;
+
+ /*
+ * check what needs to be restored.
+ * If owner == task, our state is still live and we could
+ * just reactivate and go. However, we need to check for the
+ * following conditions:
+ * - pmu owner != task
+ * - PMDs were modified
+ * - PMCs were modified
+ * - arch modifies PMC to stop monitoring
+ * - there was an in-flight interrupt at pfm_ctxswout_thread()
+ *
+ * if anyone of these is true, we cannot take the short path, i.e,
+ * just restore info + arch_ctxswin and return
+ */
+ if (set_priv_flags & PFM_SETFL_PRIV_MOD_PMDS)
+ pfm_arch_restore_pmds(ctx, set);
+
+ /*
+ * need to check if had in-flight interrupt at time of pfm_ctxswout_thread().
+ * If at least one bit set, then we must replay the interrupt to avoid
+ * losing some important performance data.
+ */
+ if (set->npend_ovfls) {
+ pfm_arch_resend_irq();
+ __get_cpu_var(pfm_stats).pfm_ovfl_intr_replay_count++;
+ }
+
+ if (set_priv_flags & PFM_SETFL_PRIV_MOD_PMCS)
+ pfm_arch_restore_pmcs(ctx, set);
+
+ set->priv_flags &= ~PFM_SETFL_PRIV_MOD_BOTH;
+
+ /*
+ * establish new ownership.
+ */
+ pfm_set_pmu_owner(task, ctx);
+
+ /*
+ * reactivate monitoring
+ */
+ pfm_arch_ctxswin(task, ctx, set);
+}
+#endif /* !CONFIG_SMP */
+
+static void pfm_ctxswin_sys(struct task_struct *task, struct pfm_context *ctx,
+ struct pfm_event_set *set)
+{
+ unsigned long info;
+ u32 set_flags;
+
+ info = __get_cpu_var(pfm_syst_info);
+
+ /*
+ * don't do anything before started
+ */
+ if (ctx->flags.started == 0)
+ return;
+
+ set_flags = set->flags;
+
+ /*
+ * pid 0 is guaranteed to be the idle task. There is one such task with pid 0
+ * on each CPU, so we can rely on the pid to identify the idle task.
+ */
+ if (task->pid == 0 && (set_flags & PFM_SETFL_EXCL_IDLE) != 0)
+ pfm_arch_stop(task ,ctx, set);
+ else
+ pfm_arch_ctxswin(task, ctx, set);
+}
+
+void __pfm_ctxswin(struct task_struct *task)
+{
+ struct pfm_context *ctx, *ctxp;
+ struct pfm_event_set *set;
+ int must_force_reload = 0;
+ u64 now_itc;
+
+ ctxp = __get_cpu_var(pmu_ctx);
+ ctx = task->pfm_context;
+
+ /*
+ * system-wide : pmu_ctx must not be NULL to proceed
+ * per-thread UP: pmu_ctx may be NULL if no left-over owner
+ * per-thread SMP: pmu_ctx is always NULL coming in
+ */
+ if (ctxp == NULL && ctx == NULL)
+ return;
+
+#ifdef CONFIG_SMP
+ /*
+ * if ctxp != 0, it means we are in system-wide mode.
+ * thereore ctx is NULL (mutual exclusion)
+ */
+ if (ctxp)
+ ctx = ctxp;
+#else
+ /*
+ * someone used the PMU, first push it out and
+ * then we'll be able to install our stuff !
+ */
+ if (ctxp && ctxp->flags.system)
+ ctx = ctxp;
+ else if (ctx) {
+ if (ctxp && ctxp != ctx) {
+ pfm_save_pmds_release(ctxp);
+ must_force_reload = 1;
+ }
+ } else
+ return;
+#endif
+ spin_lock(&ctx->lock);
+
+ set = ctx->active_set;
+
+ if (ctx->flags.system)
+ pfm_ctxswin_sys(task, ctx, set);
+ else
+ pfm_ctxswin_thread(task, ctx, set, must_force_reload);
+
+ /*
+ * ctx->duration does count even when context in MASKED state
+ * set->duration does not count when context in MASKED state.
+ * But the set->duration_start is reset in unmask_monitoring()
+ */
+
+ now_itc = pfm_arch_get_itc();
+
+ ctx->duration_start = now_itc;
+ set->duration_start = now_itc;
+
+ spin_unlock(&ctx->lock);
+}
+
+/*
+ * interrupts are masked, runqueue lock is held.
+ *
+ * In UP. we simply stop monitoring and leave the state
+ * in place, i.e., lazy save
+ */
+void pfm_ctxswout_thread(struct task_struct *task, struct pfm_context *ctx,
+ struct pfm_event_set *set)
+{
+ BUG_ON(task->pfm_context != ctx);
+
+ /*
+ * stop monitoring and collect any pending
+ * overflow information into set_povfl_pmds
+ * and set_npend_ovfls for use on ctxswin_thread()
+ * to potentially replay the PMU interrupt
+ *
+ * The key point is that we cannot afford to loose a PMU
+ * interrupt. We cannot cancel in-flight interrupts, therefore
+ * we let them happen and be treated as spurious and then we
+ * replay them on ctxsw in.
+ */
+ pfm_arch_ctxswout(task, ctx, set);
+
+#ifdef CONFIG_SMP
+ /*
+ * release ownership of this PMU.
+ * PM interrupts are masked, so nothing
+ * can happen.
+ */
+ pfm_set_pmu_owner(NULL, NULL);
+
+ /*
+ * we systematically save the PMD that we effectively
+ * use. In SMP, we have no guarantee we will be scheduled
+ * on the same CPU again.
+ */
+ pfm_modview_begin(set);
+ pfm_arch_save_pmds(ctx, set);
+ pfm_modview_end(set);
+#endif
+
+ /*
+ * clear cpuinfo, cpuinfo is used in
+ * per task mode with the set time switch flag.
+ */
+ __get_cpu_var(pfm_syst_info) = 0;
+}
+
+static void pfm_ctxswout_sys(struct task_struct *task, struct pfm_context *ctx,
+ struct pfm_event_set *set)
+{
+ u32 set_flags;
+
+ /*
+ * do nothing before started
+ * XXX: assumes cannot be started from user level
+ */
+ if (ctx->flags.started == 0)
+ return;
+
+ set_flags = set->flags;
+
+ /*
+ * restore monitoring if set has EXCL_IDLE and task was idle task
+ */
+ if (task->pid == 0 && (set_flags & PFM_SETFL_EXCL_IDLE) != 0) {
+ pfm_arch_start(task, ctx, set);
+ } else {
+ pfm_arch_ctxswout(task, ctx, set);
+ }
+}
+
+/*
+ * we come here on every context switch out.
+ */
+void __pfm_ctxswout(struct task_struct *task)
+{
+ struct pfm_context *ctx;
+ struct pfm_event_set *set;
+ u64 now_itc, diff;
+
+ ctx = __get_cpu_var(pmu_ctx);
+ if (ctx == NULL)
+ return;
+
+ spin_lock(&ctx->lock);
+
+ now_itc = pfm_arch_get_itc();
+ set = ctx->active_set;
+
+ if (ctx->flags.system) {
+ pfm_ctxswout_sys(task, ctx, set);
+ } else {
+ /*
+ * in UP, due to lazy save, we may have a
+ * context loaded onto the PMU BUT it may not
+ * be the one from the current task. In that case
+ * simply skip everything else
+ */
+ if (task->pfm_context == NULL)
+ goto skip_itc;
+
+ pfm_ctxswout_thread(task, ctx, set);
+ }
+
+ diff = now_itc - ctx->duration_start;
+ ctx->duration += diff;
+
+ /*
+ * accumulate only when set is actively monitoring,
+ */
+ if (ctx->state == PFM_CTX_LOADED)
+ set->duration += now_itc - set->duration_start;
+
+skip_itc:
+ spin_unlock(&ctx->lock);
+}
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
