x86/ucode: Drop ops->free_patch()

With the newly cleaned up vendor logic, each struct microcode_patch is a
trivial object in memory with no dependent allocations.

This is unlikely to change moving forwards, and function pointers are
expensive in the days of retpoline.  Move the responsibility to xfree() back
to common code.  If the need does arise in the future, we can consider
reintroducing the hook.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

diff --git a/xen/arch/x86/cpu/microcode/amd.c b/xen/arch/x86/cpu/microcode/amd.c
index 0ca0e9a038e46b2d55b99fd7df9f8263b01444c8..e23bdef6f2c0036bca695e1b7f0b2d97fc02899e 100644 (file)
--- a/xen/arch/x86/cpu/microcode/amd.c
+++ b/xen/arch/x86/cpu/microcode/amd.c
@@ -188,11 +188,6 @@ static enum microcode_match_result microcode_fits(
     return NEW_UCODE;
 }
 
-static void free_patch(struct microcode_patch *patch)
-{
-    xfree(patch);
-}
-
 static enum microcode_match_result compare_header(
     const struct microcode_patch *new, const struct microcode_patch *old)
 {
@@ -418,6 +413,5 @@ const struct microcode_ops amd_ucode_ops = {
     .start_update                     = start_update,
     .end_update_percpu                = svm_host_osvw_init,
 #endif
-    .free_patch                       = free_patch,
     .compare_patch                    = compare_patch,
 };

diff --git a/xen/arch/x86/cpu/microcode/core.c b/xen/arch/x86/cpu/microcode/core.c
index b3e5913d49f3dabee5a0cf9e8bb07f1c52daa7b2..53e447ea9a017683cf198dadc8eadc7111588615 100644 (file)
--- a/xen/arch/x86/cpu/microcode/core.c
+++ b/xen/arch/x86/cpu/microcode/core.c
@@ -243,9 +243,9 @@ static struct microcode_patch *parse_blob(const char *buf, size_t len)
     return NULL;
 }
 
-static void microcode_free_patch(struct microcode_patch *microcode_patch)
+static void microcode_free_patch(struct microcode_patch *patch)
 {
-    microcode_ops->free_patch(microcode_patch);
+    xfree(patch);
 }
 
 /* Return true if cache gets updated. Otherwise, return false */

diff --git a/xen/arch/x86/cpu/microcode/intel.c b/xen/arch/x86/cpu/microcode/intel.c
index 9cb077b583f61eced7b1714db82e5a84ce81a5e6..29745ed55f04b5cbab72ee5994c8ea7d22941868 100644 (file)
--- a/xen/arch/x86/cpu/microcode/intel.c
+++ b/xen/arch/x86/cpu/microcode/intel.c
@@ -245,11 +245,6 @@ static enum microcode_match_result microcode_update_match(
     return mc->rev > cpu_sig->rev ? NEW_UCODE : OLD_UCODE;
 }
 
-static void free_patch(struct microcode_patch *patch)
-{
-    xfree(patch);
-}
-
 static enum microcode_match_result compare_patch(
     const struct microcode_patch *new, const struct microcode_patch *old)
 {
@@ -356,6 +351,5 @@ const struct microcode_ops intel_ucode_ops = {
     .cpu_request_microcode            = cpu_request_microcode,
     .collect_cpu_info                 = collect_cpu_info,
     .apply_microcode                  = apply_microcode,
-    .free_patch                       = free_patch,
     .compare_patch                    = compare_patch,
 };

diff --git a/xen/arch/x86/cpu/microcode/private.h b/xen/arch/x86/cpu/microcode/private.h
index d31bcf14b1928050f0368e0f50e9ce1845a193d8..878f8d805fcb7d97f0ffa5bda66cc24de172105f 100644 (file)
--- a/xen/arch/x86/cpu/microcode/private.h
+++ b/xen/arch/x86/cpu/microcode/private.h
@@ -25,7 +25,7 @@ struct microcode_ops {
      *
      * If one is found, allocate and return a struct microcode_patch
      * encapsulating the appropriate microcode patch.  Does not alias the
-     * original buffer.
+     * original buffer.  Must be suitable to be freed with a single xfree().
      *
      * If one is not found, (nothing matches the current CPU), return NULL.
      * Also may return ERR_PTR(-err), e.g. bad container, out of memory.
@@ -56,9 +56,6 @@ struct microcode_ops {
      */
     void (*end_update_percpu)(void);
 
-    /* Free a patch previously allocated by cpu_request_microcode(). */
-    void (*free_patch)(struct microcode_patch *patch);
-
     /*
      * Given two patches, are they both applicable to the current CPU, and is
      * new a higher revision than old?