d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

hwpmc: simplify calling convention for hwpmc interrupt handling

Browse Source 
pmc_process_interrupt takes 5 arguments when only 3 are needed.
cpu is always available in curcpu and inuserspace can always be
derived from the passed trapframe.

While facially a reasonable cleanup this change was motivated
by the need to workaround a compiler bug.

core2_intr(cpu, tf) ->
  pmc_process_interrupt(cpu, ring, pmc, tf, inuserspace) ->
    pmc_add_sample(cpu, ring, pm, tf, inuserspace)

In the process of optimizing the tail call the tf pointer was getting
clobbered:

(kgdb) up
    at /storage/mmacy/devel/freebsd/sys/dev/hwpmc/hwpmc_mod.c:4709
4709                                pmc_save_kernel_callchain(ps->ps_pc,
(kgdb) up
1205                    error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,

resulting in a crash in pmc_save_kernel_callchain.
This commit is contained in:
Matt Macy 2018-06-08 04:58:03 +00:00
parent dfa5753e09
commit eb7c901995
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=334827
18 changed files with 46 additions and 56 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
sys/amd64/amd64/trap.c
View File

@ -214,7 +214,7 @@ trap(struct trapframe *frame)
* the NMI was consumed by it and we can return immediately.
*/
if (pmc_intr != NULL &&
(*pmc_intr)(PCPU_GET(cpuid), frame) != 0)
(*pmc_intr)(frame) != 0)
return;
#endif

2
sys/arm/arm/pmu.c
View File

@ -123,7 +123,7 @@ pmu_intr(void *arg)
/* Only call into the HWPMC framework if we know there is work. */
if (r != 0 && pmc_intr) {
tf = arg;
(*pmc_intr)(PCPU_GET(cpuid), tf);
(*pmc_intr)(tf);
}
#endif

8
sys/dev/hwpmc/hwpmc_amd.c
View File

@ -627,14 +627,15 @@ amd_stop_pmc(int cpu, int ri)
*/
static int
amd_intr(int cpu, struct trapframe *tf)
amd_intr(struct trapframe *tf)
{
int i, error, retval;
int i, error, retval, cpu;
uint32_t config, evsel, perfctr;
struct pmc *pm;
struct amd_cpu *pac;
pmc_value_t v;
cpu = curcpu;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[amd,%d] out of range CPU %d", __LINE__, cpu));
@ -688,8 +689,7 @@ amd_intr(int cpu, struct trapframe *tf)
wrmsr(perfctr, AMD_RELOAD_COUNT_TO_PERFCTR_VALUE(v));
/* Restart the counter if logging succeeded. */
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error == 0)
wrmsr(evsel, config);
}

8
sys/dev/hwpmc/hwpmc_arm64.c
View File

@ -323,18 +323,19 @@ arm64_release_pmc(int cpu, int ri, struct pmc *pmc)
}
static int
arm64_intr(int cpu, struct trapframe *tf)
arm64_intr(struct trapframe *tf)
{
struct arm64_cpu *pc;
int retval, ri;
struct pmc *pm;
int error;
int reg;
int reg, cpu;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[arm64,%d] CPU %d out of range", __LINE__, cpu));
retval = 0;
cpu = curcpu;
pc = arm64_pcpu[cpu];
for (ri = 0; ri < arm64_npmcs; ri++) {
@ -357,8 +358,7 @@ arm64_intr(int cpu, struct trapframe *tf)
if (pm->pm_state != PMC_STATE_RUNNING)
continue;
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error)
arm64_stop_pmc(cpu, ri);

8
sys/dev/hwpmc/hwpmc_armv7.c
View File

@ -307,18 +307,19 @@ armv7_release_pmc(int cpu, int ri, struct pmc *pmc)
}
static int
armv7_intr(int cpu, struct trapframe *tf)
armv7_intr(struct trapframe *tf)
{
struct armv7_cpu *pc;
int retval, ri;
struct pmc *pm;
int error;
int reg;
int reg, cpu;
KASSERT(cpu >= 0 && cpu < pmc_cpu_max(),
("[armv7,%d] CPU %d out of range", __LINE__, cpu));
retval = 0;
cpu = curcpu;
pc = armv7_pcpu[cpu];
for (ri = 0; ri < armv7_npmcs; ri++) {
@ -348,8 +349,7 @@ armv7_intr(int cpu, struct trapframe *tf)
if (pm->pm_state != PMC_STATE_RUNNING)
continue;
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error)
armv7_stop_pmc(cpu, ri);

21
sys/dev/hwpmc/hwpmc_core.c
View File

@ -1056,7 +1056,7 @@ iap_initialize(struct pmc_mdep *md, int maxcpu, int npmc, int pmcwidth,
}
static int
core_intr(int cpu, struct trapframe *tf)
core_intr(struct trapframe *tf)
{
pmc_value_t v;
struct pmc *pm;
@ -1064,11 +1064,11 @@ core_intr(int cpu, struct trapframe *tf)
int error, found_interrupt, ri;
uint64_t msr;
PMCDBG3(MDP,INT, 1, "cpu=%d tf=0x%p um=%d", cpu, (void *) tf,
PMCDBG3(MDP,INT, 1, "cpu=%d tf=0x%p um=%d", curcpu, (void *) tf,
TRAPF_USERMODE(tf));
found_interrupt = 0;
cc = core_pcpu[cpu];
cc = core_pcpu[curcpu];
for (ri = 0; ri < core_iap_npmc; ri++) {
@ -1084,8 +1084,7 @@ core_intr(int cpu, struct trapframe *tf)
if (pm->pm_state != PMC_STATE_RUNNING)
continue;
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
v = pm->pm_sc.pm_reloadcount;
v = iap_reload_count_to_perfctr_value(v);
@ -1117,7 +1116,7 @@ core_intr(int cpu, struct trapframe *tf)
}
static int
core2_intr(int cpu, struct trapframe *tf)
core2_intr(struct trapframe *tf)
{
int error, found_interrupt, n;
uint64_t flag, intrstatus, intrenable, msr;
@ -1141,7 +1140,7 @@ core2_intr(int cpu, struct trapframe *tf)
(uintmax_t) intrstatus);
found_interrupt = 0;
cc = core_pcpu[cpu];
cc = core_pcpu[curcpu];
KASSERT(cc != NULL, ("[core,%d] null pcpu", __LINE__));
@ -1173,8 +1172,7 @@ core2_intr(int cpu, struct trapframe *tf)
!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
continue;
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error)
intrenable &= ~flag;
@ -1184,7 +1182,7 @@ core2_intr(int cpu, struct trapframe *tf)
/* Reload sampling count. */
wrmsr(IAF_CTR0 + n, v);
PMCDBG4(MDP,INT, 1, "iaf-intr cpu=%d error=%d v=%jx(%jx)", cpu,
PMCDBG4(MDP,INT, 1, "iaf-intr cpu=%d error=%d v=%jx(%jx)", curcpu,
error, (uintmax_t) v, (uintmax_t) rdpmc(IAF_RI_TO_MSR(n)));
}
@ -1202,8 +1200,7 @@ core2_intr(int cpu, struct trapframe *tf)
!PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm)))
continue;
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error)
intrenable &= ~flag;

3
sys/dev/hwpmc/hwpmc_mips.c
View File

@ -289,8 +289,7 @@ mips_pmc_intr(int cpu, struct trapframe *tf)
retval = 1;
if (pm->pm_state != PMC_STATE_RUNNING)
continue;
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error) {
/* Clear/disable the relevant counter */
if (ri == 0)

22
sys/dev/hwpmc/hwpmc_mod.c
View File

@ -207,8 +207,7 @@ static int pmc_debugflags_parse(char *newstr, char *fence);
#endif
static int load(struct module *module, int cmd, void *arg);
static int pmc_add_sample(int cpu, int ring, struct pmc *pm,
struct trapframe *tf, int inuserspace);
static int pmc_add_sample(int ring, struct pmc *pm, struct trapframe *tf);
static void pmc_add_thread_descriptors_from_proc(struct proc *p,
struct pmc_process *pp);
static int pmc_attach_process(struct proc *p, struct pmc *pm);
@ -4640,10 +4639,9 @@ pmc_post_callchain_callback(void)
*/
static int
pmc_add_sample(int cpu, int ring, struct pmc *pm, struct trapframe *tf,
int inuserspace)
pmc_add_sample(int ring, struct pmc *pm, struct trapframe *tf)
{
int error, callchaindepth;
int error, cpu, callchaindepth, inuserspace;
struct thread *td;
struct pmc_sample *ps;
struct pmc_samplebuffer *psb;
@ -4653,8 +4651,9 @@ pmc_add_sample(int cpu, int ring, struct pmc *pm, struct trapframe *tf,
/*
* Allocate space for a sample buffer.
*/
cpu = curcpu;
psb = pmc_pcpu[cpu]->pc_sb[ring];
inuserspace = TRAPF_USERMODE(tf);
ps = psb->ps_write;
if (ps->ps_nsamples == PMC_SAMPLE_INUSE) {
counter_u64_add(ps->ps_pmc->pm_runcount, -1);
@ -4743,19 +4742,18 @@ pmc_add_sample(int cpu, int ring, struct pmc *pm, struct trapframe *tf,
*/
int
pmc_process_interrupt(int cpu, int ring, struct pmc *pm, struct trapframe *tf,
int inuserspace)
pmc_process_interrupt(int ring, struct pmc *pm, struct trapframe *tf)
{
struct thread *td;
td = curthread;
if ((pm->pm_flags & PMC_F_USERCALLCHAIN) &&
(td->td_proc->p_flag & P_KPROC) == 0 &&
!inuserspace) {
(td->td_proc->p_flag & P_KPROC) == 0 &&
!TRAPF_USERMODE(tf)) {
atomic_add_int(&curthread->td_pmcpend, 1);
return (pmc_add_sample(cpu, PMC_UR, pm, tf, 0));
return (pmc_add_sample(PMC_UR, pm, tf));
}
return (pmc_add_sample(cpu, ring, pm, tf, inuserspace));
return (pmc_add_sample(ring, pm, tf));
}
/*

3
sys/dev/hwpmc/hwpmc_mpc7xxx.c
View File

@ -702,8 +702,7 @@ mpc7xxx_intr(int cpu, struct trapframe *tf)
continue;
/* Stop the counter if logging fails. */
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error != 0)
mpc7xxx_stop_pmc(cpu, i);

3
sys/dev/hwpmc/hwpmc_ppc970.c
View File

@ -519,8 +519,7 @@ ppc970_intr(int cpu, struct trapframe *tf)
if (pm->pm_state != PMC_STATE_RUNNING)
continue;
error = pmc_process_interrupt(cpu, PMC_HR, pm, tf,
TRAPF_USERMODE(tf));
error = pmc_process_interrupt(PMC_HR, pm, tf);
if (error != 0)
ppc970_stop_pmc(cpu, i);

3
sys/dev/hwpmc/hwpmc_soft.c
View File

@ -425,8 +425,7 @@ pmc_soft_intr(struct pmckern_soft *ks)
else
continue;
user_mode = TRAPF_USERMODE(ks->pm_tf);
error = pmc_process_interrupt(ks->pm_cpu, PMC_SR, pm,
ks->pm_tf, user_mode);
error = pmc_process_interrupt(PMC_SR, pm, ks->pm_tf);
if (error) {
soft_stop_pmc(ks->pm_cpu, ri);
continue;

2
sys/i386/i386/trap.c
View File

@ -248,7 +248,7 @@ trap(struct trapframe *frame)
* return immediately.
*/
if (pmc_intr != NULL &&
(*pmc_intr)(PCPU_GET(cpuid), frame) != 0)
(*pmc_intr)(frame) != 0)
return;
#endif

2
sys/kern/kern_pmc.c
View File

@ -71,7 +71,7 @@ const int pmc_kernel_version = PMC_KERNEL_VERSION;
int __read_mostly (*pmc_hook)(struct thread *td, int function, void *arg) = NULL;
/* Interrupt handler */
int __read_mostly (*pmc_intr)(int cpu, struct trapframe *tf) = NULL;
int __read_mostly (*pmc_intr)(struct trapframe *tf) = NULL;
DPCPU_DEFINE(uint8_t, pmc_sampled);

2
sys/mips/atheros/apb.c
View File

@ -388,7 +388,7 @@ apb_filter(void *arg)
tf = td->td_intr_frame;
if (pmc_intr)
(*pmc_intr)(PCPU_GET(cpuid), tf);
(*pmc_intr)(PCPU_GET(tf);
continue;
}
/* Ignore timer interrupts */

2
sys/mips/cavium/octeon_pmc.c
View File

@ -111,7 +111,7 @@ octeon_pmc_intr(void *arg)
struct trapframe *tf = PCPU_GET(curthread)->td_intr_frame;
if (pmc_intr)
(*pmc_intr)(PCPU_GET(cpuid), tf);
(*pmc_intr)(PCPU_GET(tf);
return (FILTER_HANDLED);
}

2
sys/powerpc/powerpc/interrupt.c
View File

@ -112,7 +112,7 @@ powerpc_interrupt(struct trapframe *framep)
case EXC_PERF:
critical_enter();
KASSERT(pmc_intr != NULL, ("Performance exception, but no handler!"));
(*pmc_intr)(PCPU_GET(cpuid), framep);
(*pmc_intr)(framep);
if (pmc_hook && (PCPU_GET(curthread)->td_pflags & TDP_CALLCHAIN))
pmc_hook(PCPU_GET(curthread), PMC_FN_USER_CALLCHAIN, framep);
critical_exit();

7
sys/sys/pmc.h
View File

@ -61,7 +61,7 @@
*
* The patch version is incremented for every bug fix.
*/
#define PMC_VERSION_MAJOR 0x08
#define PMC_VERSION_MAJOR 0x09
#define PMC_VERSION_MINOR 0x03
#define PMC_VERSION_PATCH 0x0000
@ -1053,7 +1053,7 @@ struct pmc_mdep {
int (*pmd_switch_out)(struct pmc_cpu *_p, struct pmc_process *_pp);
/* handle a PMC interrupt */
int (*pmd_intr)(int _cpu, struct trapframe *_tf);
int (*pmd_intr)(struct trapframe *_tf);
/*
* PMC class dependent information.
@ -1209,8 +1209,7 @@ MALLOC_DECLARE(M_PMC);
struct pmc_mdep *pmc_md_initialize(void); /* MD init function */
void pmc_md_finalize(struct pmc_mdep *_md); /* MD fini function */
int pmc_getrowdisp(int _ri);
int pmc_process_interrupt(int _cpu, int _ring, struct pmc *_pm,
struct trapframe *_tf, int _inuserspace);
int pmc_process_interrupt(int _ring, struct pmc *_pm, struct trapframe *_tf);
int pmc_save_kernel_callchain(uintptr_t *_cc, int _maxsamples,
struct trapframe *_tf);
int pmc_save_user_callchain(uintptr_t *_cc, int _maxsamples,

2
sys/sys/pmckern.h
View File

@ -176,7 +176,7 @@ struct pmc_domain_buffer_header {
/* hook */
extern int (*pmc_hook)(struct thread *_td, int _function, void *_arg);
extern int (*pmc_intr)(int _cpu, struct trapframe *_frame);
extern int (*pmc_intr)(struct trapframe *_frame);
/* SX lock protecting the hook */
extern struct sx pmc_sx;