AcoSail/kernel_optimize_test
8
0
Fork 0
forked from luck/tmp_suning_uos_patched
Code Pull Requests Activity

powerpc/perf: Consolidate perf_callchain_user_[64|32]()

Browse Source 
perf_callchain_user_64() and perf_callchain_user_32() are nearly
identical. Consolidate into one function with thin wrappers.

Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
[mpe: Adapt to copy_from_user_nofault(), minor formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200406210022.32265-1-msuchanek@suse.de
This commit is contained in:
Michal Suchanek 2020-04-06 23:00:22 +02:00 committed by Michael Ellerman
parent a0ff72f9f5
commit d3a133aa0e
3 changed files with 29 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

25
arch/powerpc/perf/callchain.h
View File

@ -2,7 +2,7 @@
#ifndef _POWERPC_PERF_CALLCHAIN_H
#define _POWERPC_PERF_CALLCHAIN_H
int read_user_stack_slow(void __user *ptr, void *buf, int nb);
int read_user_stack_slow(const void __user *ptr, void *buf, int nb);
void perf_callchain_user_64(struct perf_callchain_entry_ctx *entry,
struct pt_regs *regs);
void perf_callchain_user_32(struct perf_callchain_entry_ctx *entry,
@ -16,4 +16,27 @@ static inline bool invalid_user_sp(unsigned long sp)
return (!sp || (sp & mask) || (sp > top));
}
/*
* On 32-bit we just access the address and let hash_page create a
* HPTE if necessary, so there is no need to fall back to reading
* the page tables. Since this is called at interrupt level,
* do_page_fault() won't treat a DSI as a page fault.
*/
static inline int __read_user_stack(const void __user *ptr, void *ret,
size_t size)
{
unsigned long addr = (unsigned long)ptr;
int rc;
if (addr > TASK_SIZE - size || (addr & (size - 1)))
return -EFAULT;
rc = copy_from_user_nofault(ret, ptr, size);
if (IS_ENABLED(CONFIG_PPC64) && rc)
return read_user_stack_slow(ptr, ret, size);
return rc;
}
#endif /* _POWERPC_PERF_CALLCHAIN_H */

21
arch/powerpc/perf/callchain_32.c
View File

@ -30,26 +30,9 @@
#endif /* CONFIG_PPC64 */
/*
* On 32-bit we just access the address and let hash_page create a
* HPTE if necessary, so there is no need to fall back to reading
* the page tables. Since this is called at interrupt level,
* do_page_fault() won't treat a DSI as a page fault.
*/
static int read_user_stack_32(unsigned int __user *ptr, unsigned int *ret)
static int read_user_stack_32(const unsigned int __user *ptr, unsigned int *ret)
{
int rc;
if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned int) ||
((unsigned long)ptr & 3))
return -EFAULT;
rc = copy_from_user_nofault(ret, ptr, sizeof(*ret));
if (IS_ENABLED(CONFIG_PPC64) && rc)
return read_user_stack_slow(ptr, ret, 4);
return rc;
return __read_user_stack(ptr, ret, sizeof(*ret));
}
/*

13
arch/powerpc/perf/callchain_64.c
View File

@ -23,7 +23,7 @@
* interrupt context, so if the access faults, we read the page tables
* to find which page (if any) is mapped and access it directly.
*/
int read_user_stack_slow(void __user *ptr, void *buf, int nb)
int read_user_stack_slow(const void __user *ptr, void *buf, int nb)
{
unsigned long addr = (unsigned long) ptr;
@ -44,16 +44,9 @@ int read_user_stack_slow(void __user *ptr, void *buf, int nb)
return -EFAULT;
}
static int read_user_stack_64(unsigned long __user *ptr, unsigned long *ret)
static int read_user_stack_64(const unsigned long __user *ptr, unsigned long *ret)
{
if ((unsigned long)ptr > TASK_SIZE - sizeof(unsigned long) ||
((unsigned long)ptr & 7))
return -EFAULT;
if (!copy_from_user_nofault(ret, ptr, sizeof(*ret)))
return 0;
return read_user_stack_slow(ptr, ret, 8);
return __read_user_stack(ptr, ret, sizeof(*ret));
}
/*